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Effects of vitamin D3 supplementation and UVb exposure on the growth and plasma concentration of vitamin D3 metabolites in juvenile bearded dragons (Pogona vitticeps)

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Abstract

The effectiveness of dietary vitamin D3 and UVb exposure on plasma vitamin D metabolites in growing bearded dragons (Pogona vitticeps) was studied. A total of 84 (40 males and 44 females) newly hatched bearded dragons were allocated to six levels of oral vitamin D3 supplementation (0 to 400%) or six UVb exposure times (2 to 12 h). At 3 and 6 months of age, blood samples were obtained from each animal and analysed for 25(OH)D3 and 1,25(OH)2D3. At 3 months of age, plasma concentrations of 25(OH)D3 did not increase with increasing vitamin D3 supplementation unlike the 1,25(OH)2D3. At 6 months of age, plasma concentrations of both 25(OH)D(3) and 1,25(OH)2D3 increased with increasing vitamin D(3) supplementation. Plasma concentrations in UVb-exposed animals were 18 times higher for 25(OH)D3 (178.4+/-9.0 vs. 9.9+/-1.3 nmol/L) and 5.3 times higher for 1,25(OH)2D3 (1.205+/-0.100 vs. 0.229+/-0.025 nmol/L) than in vitamin D(3) supplemented animals at 6 months of age. This study shows that 2h of UVb exposure enables adequate physiological concentrations of plasma vitamin D metabolites to be maintained in growing bearded dragons. Oral supplementation of vitamin D(3) is ineffective in raising plasma concentrations of 25(OH)D3 and 1,25(OH)2D3 to concentrations observed in UVb-exposed animals.

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... In growing dairy goats (Capra hircus) and sheep (Ovis aries), a vitamin D 3 -reduced diet combined with missing ultraviolet B (UVB) exposure leads to a sharp drop in the vitamin D 3 status [2]. Such findings reinforce the results of studies that employed vitamin D 3 supplementation and UVB exposure in juvenile bearded dragons (Pogona vitticeps) [3]. The study reported by Oonincx et al. [3] showed that 2 h of UVB exposure enables adequate physiological concentrations of plasma vitamin D 3 metabolites to be maintained in growing bearded dragons. ...
... Such findings reinforce the results of studies that employed vitamin D 3 supplementation and UVB exposure in juvenile bearded dragons (Pogona vitticeps) [3]. The study reported by Oonincx et al. [3] showed that 2 h of UVB exposure enables adequate physiological concentrations of plasma vitamin D 3 metabolites to be maintained in growing bearded dragons. Vitamin D 3 also has a precise role in immunoregulation in response to microbial threats [4]. ...
... The control animals received the basal diet without supplementation. The basal diet was composed of 69.3% oats, 1.35% soybean meal, 2.05% corn, 26.04% alfalfa meal, 0.93% cottonseed hulls, 0.31% dicalcium phosphate, and 0.06% vitamin A, D 3 , and E supplements. The experimental and control animals were fed twice a day, in the morning and the evening. ...
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Mastitis-causing bacteria can establish persistent infections in the mammary glands of commercially important dairy animals despite the presence of strong specific humoral and cellular immune mechanisms. We investigated the effect of vitamin D3 in the diet at a set level, but in two different forms (i.e., unencapsulated and encapsulated by complex coacervation with sulfur-saturated bovine lactoferrin-alginate using microbial transglutaminase-catalyzed crosslinking) on the immune response in late-lactating dairy goats. Dairy goats (n = 18) were randomly assigned to three experimental groups (n = 6). Dairy goats were orally administered 0.35 mg of vitamin D3/day in the unencapsulated form and 0.35 mg of vitamin D3/day in the encapsulated powder form. Another group received the basal diet. The experimental period lasted 6 weeks. The blood serum concentrations of 25-hydroxyvitamin D3 [25-(OH)-D3], lactoferrin, immunoglobulin A (IgA), and interferon-gamma (INF-γ) were measured. There were major differences in these parameters between dietary groups. However, the delivery of vitamin D3 in the encapsulated powder form to dairy goats resulted in a marked increase in 25-(OH)-D3 concentration in serum, while the serum level of lactoferrin also increased. Alternatively, the serum levels of IgA and the immunomodulatory cytokine INF-γ were elevated following supplementation with the encapsulated vitamin D3. The observed effects suggest that the deliverable form of dietary vitamin D3 results in differences in the immune response in late-lactating dairy goats.
... Agamid and iguanid lizards exposed to natural sunlight also had significantly higher levels of vit D than those exposed only to artificial UV light and/or dietary vit D [37]. In a study on juvenile bearded dragons (Pogona vitticeps), ultraviolet-B radiation (UVB) exposure resulted in vitamin D levels 5-18 times higher than in the group that received dietary vit D supplementation only [38], while Purgley et al. reported that vitamin D levels of captive green sea turtles kept indoors without any exposure to ultraviolet radiation had lower vitamin D levels than those kept in outdoor facilities [39]. In addition, some studies have shown that vit D levels are lower in rehabilitated turtles than in wild-caught individuals [40,41]. ...
... PCV values at intake/capture were highest in IRG turtles (range 24.5-42.5%) and lowest in VT+ turtles (range 5-27%), with VT− turtles intermediate (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39).5%) ( Figure 1). Even though VT− turtles had intermediate values, there was a significant difference between VT+ and both IRG and VT− turtles (p < 0.005). ...
... The turtles exposed to higher UV light in addition to the oral supplement had much greater increases in plasma vitamin D levels. A study in bearded dragons similarly found that individuals given both an oral supplement and exposure to high UV light had much higher plasma vitamin D levels than those provided oral supplementation alone [38]. In this study, the changes in vitamin D were only significant in the VT+ turtles; while the VT− turtles showed the same trend, the changes were smaller and not significant. ...
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Green sea turtles (Chelonia mydas) are an endangered species, which as juveniles are prone to the debilitating disease green turtle fibropapillomatosis (FP). Previous work has shown an association between reduced immune function and FP. As vitamin D has been linked to immune function in numerous animals, the aim of this study was to compare vitamin D levels in green sea turtles with and without evident FP and determine if exposure to sunlight would influence vitamin D levels and other health parameters. Various health markers, including vitamin D, in turtles with and without evident tumors being treated at a rehabilitation facility in southeast Florida were compared to apparently healthy wild-caught juvenile green turtles. Turtles receiving treatment were housed in tanks exposed to higher or lower levels of sunlight for up to 6 months. Upon intake, tumored individuals had lower plasma vitamin D and ionized calcium levels and higher parathyroid hormone levels when compared to both wild-caught and rehabilitation turtles without evident tumors. Individuals exposed to greater sunlight showed greater increases in plasma vitamin D and a more successful recovery. The results suggest that increasing sun exposure in rehabilitation facilities may enhance health and recovery in green turtles with FP.
... Mineral content of all four species of cockroaches at both life stages was similar to that reported previously (Barker et al., 1998;Finke, 2002Finke, , 2013Martin et al., 1976;Oonincx & Dierenfeld, 2012;Oonincx et al., 2010). Adult B. dubia had greater Na and K content than the other three species, however Na and K content of all species analyzed were comparable to that of wild-caught and captive-bred feeder insects (Finke, 2002;Finke, 2013;Levy & Cromroy, 1972;Oonincx & Dierenfeld, 2012;Oonincx et al., 2010;Studier & Sevick, 1992 and G. mellonella (77.3 ppm), yet were greater than previous reports for T. molitor (39.7 ppm) (Barker et al., 1998). ...
... Mineral content of all four species of cockroaches at both life stages was similar to that reported previously (Barker et al., 1998;Finke, 2002Finke, , 2013Martin et al., 1976;Oonincx & Dierenfeld, 2012;Oonincx et al., 2010). Adult B. dubia had greater Na and K content than the other three species, however Na and K content of all species analyzed were comparable to that of wild-caught and captive-bred feeder insects (Finke, 2002;Finke, 2013;Levy & Cromroy, 1972;Oonincx & Dierenfeld, 2012;Oonincx et al., 2010;Studier & Sevick, 1992 and G. mellonella (77.3 ppm), yet were greater than previous reports for T. molitor (39.7 ppm) (Barker et al., 1998). Nymphs of G. ...
... Additionally, there are insectivore species (amphibians, birds, and reptiles) that are prone to gout and therefore roaches should be fed correctly and only a small part of these susceptible animal's diets so they do not accumulate large quantities of uric acid (Mullins & Cochran, 1976;Oros, 2019;Sabolova et al., 2021). Therefore, a mixed diet that incorporates a species and life stage variety of gut-loaded insects is recommended to provide appropriate nutrition to captive insectivores (Ferguson et al., 1996;Hoby et al., 2010;Oonincx et al., 2010). Recommendations for gut-loading diets for crickets, mealworms, and silkworms have been published previously, and future research to determine appropriate gut-loading methods in cockroach species is warranted (Finke, 2003). ...
Article
A variety of insects are fed to insectivorous animals; however, nutritional analyses are often limited to adult life stages. Four species of nymph and adult female and male cockroaches (Blaberus giganteus, Blaptica dubia, Blatta lateralis, and Gromphadorhina portentosa) were analyzed for moisture, crude protein (CP), acid detergent fiber (ADF), fat, ash, and mineral content. The small sample size of this study precluded statistical analyses, however comparatively, CP in adult B. lateralis and B. dubia was greater than the CP in nymphs of the same species. Adult and nymph B. dubia had the greatest CP (96.6% and 65.3%, respectively) compared to the other three species. Inversely, fat content in adult B. lateralis and B. dubia was lower than that of nymphs of the same species. All adults contained similar levels of ADF, yet adult B. giganteus had greater ADF than nymphs; conversely, B. lateralis and B. dubia adults had less ADF than nymphs. There were differences noted in mineral parameters among the four species and life stages. Adult B. giganteus had less Ca than G. portentosa, and the lowest Ca content of the four species of nymphs and adults analyzed. This study underscores the differences in nutrient content with respect to life stage and species in previously understudied cockroaches to improve nutrient intake in captive insectivores. HIGHLIGHTS • Some species of adult cockroaches had comparatively lower fat, higher crude protein, and Ca compared to nymphs, and demonstrated interspecies differences in nutrient profiles; these results can be used to assist in diet formulation for insectivores.
... Animals can obtain vitamin D either from the diet or via conversion of endogenous 7-dehydrocholesterol (7-DHC) to vitamin D 3 in the skin by exposure to UVb radiation (280-320 nm) and subsequent thermal isomerisation. The latter pathway is active in the great majority of animal species studied to date, including mammals (Brot et al., 2001;Cavaleros et al., 2003;Cooper et al., 1997;Hymøller & Jensen, 2010;Jakobsen et al., 2020;Kwiecinski et al., 2001;Southworth et al., 2013;Watson et al., 2014), birds (Drake et al., 2017;Edwards, 2003;Stanford, 2006) insects , and reptiles (Acierno et al., 2006;Acierno et al., 2008;Bos et al., 2018), including diurnal lizards (Ferguson et al., 2009;Gillespie et al., 2000;Laing et al., 2001;Oonincx et al., 2010;Townsend & Cole, 1985). However, this pathway is dysfunctional in some species, including cats, dogs and seals, and has limited functionality in polar bears due to absence or low levels of 7-DHC (Bouillon & Bikle, 2019;How et al., 1994;Keiver et al., 1988;Kenny et al., 1998). ...
... These species are carnivores and fulfil their vitamin D requirements via dietary intake. Conversely, the dietary route appears ineffective as the sole source T of vitamin D in certain diurnal lizards, such as Komodo dragons (Varanus komodoensis) and bearded dragons (Pogona vitticeps), which may depend on UVb radiation to obtain a suitable vitamin D status (Gillespie et al., 2000;Nijboer et al., 2001;Oonincx et al., 2010). Vitamin D 3 status is indicated by the concentration of 25(OH)D 3 in blood plasma following a primary hydroxylation in the liver (Heaney et al., 2008;Laing et al., 2001). ...
... On the other hand, many lizard species kept in zoos and private collections without access to UVb survive and reproduce without clinical signs of vitamin D deficiency such as muscle weakness, tetany, or nutritional secondary hyperparathyroidism. However, vitamin D deficiency can be present without the aforementioned conditions and limit growth and weight gain (Diehl et al., 2018;Oonincx et al., 2010). The leopard gecko (Eublepharis macularius) is a lizard species that has been kept and bred in captivity since the early 1960s (Thorogood & Whimsterf, 1979). ...
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Vitamin D is an important regulator of calcium and phosphorus homeostasis in animals. It can be acquired from the diet or synthesised de novo when skin is exposed to UVb. Vitamin D deficiency can lead to a complex of diseases collectively called metabolic bone disease (MBD). Diurnal lizards without access to UVb are prone to develop vitamin D deficiency, even when dietary vitamin D3 is provided. A trial was conducted to determine whether juvenile nocturnal lizards require access to UVb to prevent vitamin D deficiency. All leopard geckos (Eublepharis macularius) were supplemented with dietary vitamin D3. One group was exposed to low level UVb radiation (33-51 μW/cm2) from hatching until 6 months of age and a second group remained unexposed. Animals were fed ad libitum and their growth and weight gain compared with non-exposed controls. At the end of the trial, blood samples were analysed for vitamin D3 metabolites. The concentration of the vitamin D3 metabolite, 25(OH)D3, was higher in UVb exposed animals (61 ± 20 vs. 38 ± 8 nmol/L), confirming cutaneous synthesis with UVb exposure. Growth and weight gain were similar in both groups, and this, together with the absence of clinical symptoms, suggests that dietary vitamin D3 alone can meet the vitamin D requirements for growth of this nocturnal gecko, during the first six months of life. It remains to be investigated whether the higher vitamin D metabolite levels holds other health benefits for this species, such as improved bone density or immune response.
... 30,31 Alternatively, other studies have evaluated the consequences of UVB exposure to determine an appropriate range for captive animals. 11,13,[32][33][34][35] For instance, consequences of low UVB exposure include low plasma or hepatic vitamin D concentration and metabolic bone disease, evaluated by the measurement of bone mineral density via micro-computed tomography, 36 histology 37 or dual-energy X-ray absorptiometry. 38,39 A third approach is to determine if increasing the amount of UVB to which the animal is exposed can increase the plasma concentration of 25-hydroxycholecalciferol. 32,33,[40][41][42] In this approach, however, it is assumed that the highest calcidiol concentration is necessarily the best, which has not yet been demonstrated. ...
... Similarly, in bearded dragons exposed to 34 μW cm −2 UVB or given vitamin D3 orally, plasma calcidiol concentration after 6 months was higher in the group receiving UVB exposure. 34 At this irradiance, two hours or twelve hours of UVB exposure did not change the resulting calcidiol concentrations. 34 Previously, UVB lights were not recommended in carnivorous reptile species fed whole vertebrate prey due to the assumption that their requirement for vitamin D was covered by their diet. ...
... 34 At this irradiance, two hours or twelve hours of UVB exposure did not change the resulting calcidiol concentrations. 34 Previously, UVB lights were not recommended in carnivorous reptile species fed whole vertebrate prey due to the assumption that their requirement for vitamin D was covered by their diet. 6 More recent studies have shown that UVB exposure led to a significant increase of calcidiol concentration in cornsnakes (Pantherophis guttatus) 33 and red-eared sliders (Trachemys scripta elegans). ...
Article
Many animals under human care are kept indoors to prevent infectious diseases vectored by wildlife, facilitate environment control, or due to the lifestyle of their owners. However, ultraviolet radiation has documented effects on animal vision, vitamin synthesis, immunity, behavior, psychogenic disorders and on their environment. Ultraviolet-emitting lights are commercially available and the documentation of their effect on indoor-housed animals is increasing. This article reviews published information about ultraviolet effects in vertebrate animals from veterinary and ethological perspectives, and techniques used to assess ultraviolet exposure across animal taxa.
... Insects are generally considered a good source of most nutrients (DeFoliart, 1992) and many species have been analyzed for their nutrient composition. These analyses include insects taken from the field (Bukkens, 1997;Finke, 2015b;Gullan and Cranston, 2005;Punzo, 2003) and those commercially reared (Dierenfeld and King, 2008;Finke, 2002Finke, , 2013Finke, , 2015aOonincx et al., 2010;Oonincx and Dierenfeld, 2012;Ramos-Elorduy et al., 2002;Simpson and Raubenheimer, 2001). In nature, most insectivores consume insects and a variety of other arthropods including arachnids (scorpions, whipscorpion, ticks, and spiders), isopods, millipedes and centipedes. ...
... The protein content of insects is highly variable and ranges between 7.5% and 91% with many species containing around 60% protein on a dry matter basis (Barker et al., 1998;Bernard and Allen, 1997;Bukkens, 1997;Finke, 2002Finke, , 2013Oonincx et al., 2010;Oonincx and van der Poel, 2011;Oonincx and Dierenfeld, 2012;Oonincx et al., 2015;Punzo, 2003;Ramos-Elorduy et al., 2002). The protein content is commonly determined by multiplying the amount of nitrogen times 6.25, known as the crude protein content. ...
... Using a more sensitive technique, black soldier fly larvae, butter worm larvae and Turkestan roaches were shown to contain 388À633 IU vitamin D 3 /kg dry matter, while adult houseflies were still below the limit of detection (Finke, 2013). A further study reports a low vitamin D 3 level in commercially produced yellow mealworms (150 IU/kg dry matter), but a higher concentration in house crickets (934 IU/kg dry matter) (Oonincx et al., 2010). These highly variable concentrations were attained via dietary accumulation. ...
... A természetes napfény élettani hatásai -megfelelő időtartamú behatás esetén -kedvezőbbek, mint a mesterséges UV-lámpáké (31,32,36). Az utóbbi években több kísérletet végeztek, amelyekben ellenőrzött körülmények között vizsgálták az UV-fény élettani hatásait (1,2,3,8,9,11,24,25,29,34,35,36,37). Ezekben igazolódott a mesterséges UV-B-fényforrások D-vitamin-szintézisre gyakorolt pozitív hatása. ...
... Ebből arra lehet következtetni, hogy a szájon át adagolt D 3 -vitamin is megfelelő szintű ellátást biztosít. Szakállas agámák (Pogona vitticeps) esetében az UV-lámpával megvilágított csoportnál a vérben mért 25(OH)-kolekalciferol-és 1,25(OH) 2 -kolekalciferol-szintet viszont még nagy mennyiségű -a javasolt adag négyszerese -szájon át adagolt D 3 -vitaminnal sem tudták elérni (34). Ennél a fajnál már napi 2 órás, nagyobb (34 ± 3 µW/cm 2 ) vagy 12 órás kisebb (2 µW/cm 2 ) intenzitású UV-B-sugárzás hatására egyaránt megfelelőek voltak a ...
... vérparaméterek (34). Nőstény párduckaméleonok (Furcifer pardalis) hosszú időtartamú (12 óra/nap), viszonylag kis intenzitású (5-15 µW/cm 2 ) UV-B-sugárzás esetén szignifikánsan jobban keltethető tojásokat raktak, mint a több (> 15 µW/ cm 2 ) vagy kevesebb (<5 µW/cm 2 ) sugárzásnak kitett egyedek (7,8). ...
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Based on the literature and own experiences, the authors give a review on the most common disease of reptiles deriving from nutritional and housing failure, the metabolic bone disease. The aetiology and pathology of the disease is described with focus on the role of vitamin D-3 and its sources. Clinical signs, diagnostic methods and possible treatments are also shown practically. This disease can be prevented by proper housing and feeding according to the needs of the reptiles the guidelines of prevention are also described.
... Whether endogenous or dietary sources of vitamin D 3 are most important to reptiles in nature and whether the relative importance of the source differs among species remains poorly understood (Donoghue, 2006;Ferguson et al., 2009;Oonincx et al., 2013). However, both sources can affect vitamin D status in captivity in a variety of reptilian species (Ferguson et al., 1996Acierno et al., 2006Acierno et al., , 2008Oonincx et al., 2010;Selleri and Di Girolamo, 2012). Although UVB seems to be more effective than dietary sources in establishing and maintaining a high vitamin D status in some species, such the bearded dragon (Pogona viticeps) (Oonincx et al., 2010(Oonincx et al., , 2013, successful indoor maintenance and propagation of heliophilic lizards, such as the chuckwalla (Sauromalus obesus), is possible relying only on dietary vitamin D (Montanucci, 1997). ...
... However, both sources can affect vitamin D status in captivity in a variety of reptilian species (Ferguson et al., 1996Acierno et al., 2006Acierno et al., , 2008Oonincx et al., 2010;Selleri and Di Girolamo, 2012). Although UVB seems to be more effective than dietary sources in establishing and maintaining a high vitamin D status in some species, such the bearded dragon (Pogona viticeps) (Oonincx et al., 2010(Oonincx et al., , 2013, successful indoor maintenance and propagation of heliophilic lizards, such as the chuckwalla (Sauromalus obesus), is possible relying only on dietary vitamin D (Montanucci, 1997). ...
... Given that unregulated exposure of lizard skin to UVB increases vitamin D production and vitamin D status (Holick et al., 1995;Aucone et al., 2003;Ferguson et al., 2003Ferguson et al., , 2005Oonincx et al., 2010), the strong negative relationship between UVB exposure and vitamin D status during the summer suggests that the iguanas in this report were attempting to regulate their vitamin D status at set points at or below 100 ng/ml. Two lizard species, the panther chameleon (Furcifer pardalis) and the Cuban brown anole (Anolis sagrei), have been shown to regulate their exposure to UVB and to reduce their exposure when dietary vitamin D is increased (Ferguson et al., , 2013Karsten et al., 2009). ...
Article
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Four long-term captive adult rhinoceros iguanas (Cyclura cornuta) on display at the Dallas Zoo were maintained for several years in an outdoor enclosure in the summer and a smaller indoor enclosure in the winter. While fully exposed to sunlight and given the opportunity to supplement their diet with live vegetation each summer, they were deprived of the benefits of full sun exposure, including ultraviolet B (UVB) exposure, and received no dietary vitamin D for several months each winter. Maintained with this protocol, the animals appeared healthy and reproduced. However, increasing awareness of the important role of UVB in vitamin D-mediated calcium metabolism and the potential health risk of UVB and vitamin D deprivation stimulated us to focus more on seasonal changes in vitamin D status and possible subtle changes in health status throughout winter. From September 2008 to October 2010 an 85% decline in the serum 25(OH)D3 (calcidiol) concentrations were measured over each of two winters, and a half-life of 69 days was estimated for the second winter. A higher vitamin D-status (calcidiol) was restored and maintained when the iguanas were outdoors and exposed themselves to one to two Joules of UVB per day, although they may have enhanced their dietary calcium and vitamin D activity by eating cactus fruit too. Serum calcium and phosphorus concentrations remained higher than published reference values for Cyclura spp. A negative relationship between vitamin D status and voluntary UVB exposure during the summers was discovered. This suggests that the iguanas were regulating, rather than continually maximizing, their vitamin D-status at levels lower than those recorded for Cyclura in the tropics. While the iguanas appeared robust physically, had acceptable calcium and phosphorus blood concentrations, and successfully reproduced throughout the two-year monitoring period, we do not recommend extended periods of deprivation of UVB and vitamin D supplementation in winter for rock iguanas until minimally sufficient vitamin D status is more rigorously established.
... Kaméleonoknál már bizonyították, hogy az állatok, az aktuális D 3 -vitaminszintjüknek megfelelõen, több vagy kevesebb idõt töltenek az UV-lámpák alatt (24). Az utóbbi években több kísérletet végeztek (1,2,3,4,13,26,27,32), amelyekben ellenõrzött körülmények között vizsgálták az UV-fény élettani hatásait. ...
... Ebbõl arra lehet következtetni, hogy a szájon át adagolt D 3 -vitamin is megfelelõ szintû ellátást biztosít. Növendék szakállas agámáknál már napi 2 órás UV-B-sugárzás (34±3 µW/cm 2 ) is megfelelõ vérszintet alakított ki (32). Ugyanezen fajjal végzett másik kísérletben 12 órás, 2 µW/cm 2 -es érték Az Ausztráliában õshonos szakállas agáma akár fél méteresre is megnõhet A D 3 -vitamin-szintézis végett mesterséges UV-fényforrásokról érdemes gondoskodni mellett mérték a legnagyobb 25(OH)-kolekalciferol-szintet (26). ...
... A korai diagnózis felállításában a vérvizsgálatnak van elsõdleges szerepe (táblázat), ezen belül is − mivel több érték esetében még nincsenek irodalmi adatok − az össz-és az ionizált kalcium, a szervetlen foszfát, esetleg néhány enzim jöhet szóba. A költségek miatt inkább csak elvi lehetõség a 25(OH)-kolekalciferol és az 1,25(OH) 2 -kolekalciferol mérése, amelyrõl még kevés irodalmi adat áll rendelkezésre (26,32). A táblázat harmadik oszlopában látható, hogy saját mérések során egy alkalommal, egészséges állatnál is kaptunk kiugróan magas húgysavszintet (1569 µmol/l). ...
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This review presents the inland bearded dragon, which is one of the most popular lizards as a pet. The author summarises the optimal housing and feeding conditions. As they are omnivore, next to the feeds of animal origin it is also important to offer them optimal proportion of feeds of plant origin according to age (20% in juveniles and from 50-60% up to 90% in adults). Juveniles should be fed five times, adults only three times a week. The most important nutritional diseases [e.g. metabolic bone disease (MBD), obesity] are also described. As blood examination is an important diagnostic tool, the data from the literature as well as own data are also shown. Attention must be paid on the Ca and vitamin D3 supplementation as well as on the importance of artificial UV-B emission. If the vitamin supplement contains only 2000 lU/kg or less vitamin D , artificial UV-B emission (12 hours/day) is suggested. Most of the possible health problems (e.g. MBD, obesity) can be prevented by avoiding the excess amount of feeds of animal origin. Among the feeds of animal origin the ones with lower fat content (e.g. cricket vs. worms) should be preferred.
... Insects are generally considered a good source of most nutrients (DeFoliart 1992) and many insect species have been analysed for their nutrient composition. These analyses include insects taken from the field (Bukkens 1997;Punzo 2003;Gullan et al. 2005) and those commercially reared (Simpson and Raubenheimer 2001;Finke 2002;Ramos-Elorduy et al. 2002;Dierenfeld and King 2008;Oonincx, Stevens et al. 2010a;Oonincx and Dierenfeld 2012b;Finke 2013). In nature, most insectivores will feed on a variety of arthropod prey species. ...
... As a general rule, it is better for insectivores to be offered a varied diet rather than a single insect species (Bernard and Allen 1997). When the insectivore is able to select between different insects offered, this allows self-selection of nutrients (Oonincx et al. 2010a;Senar, Møller et al. 2010). ...
... The protein content of insects is highly variable and ranges between 7.5% and 91% with many species containing around 60% protein on a dry matter basis (Bernard et al. 1997;Bukkens 1997;Barker et al. 1998;Finke 2002;Ramos-Elorduy et al. 2002;Punzo 2003;Oonincx et al. 2010a;Oonincx et al. 2012b;Finke 2013). Protein content is commonly determined by multiplying the amount of nitrogen times 6.25, known as the crude protein content. ...
... To date, the majority of the research evaluating the effects of UVB radiation on reptiles has focused on diurnal species (Allen et al., 1999;Laing and Fraser, 1999;Carman et al., 2000;Laing et al., 2001;Ferguson et al., 2003Ferguson et al., , 2005Acierno et al., 2006Acierno et al., , 2008Oonincx et al., 2010;Selleri and Di Girolamo, 2012). Although originally focused on lizards (Allen et al., 1999;Laing and Fraser, 1999;Carman et al., 2000;Laing et al., 2001;Ferguson et al., 2003Ferguson et al., , 2005Oonincx et al., 2010), more recent examples in chelonians (Acierno et al., 2006;Selleri and Di Girolamo, 2012) and a snake species (Acierno et al., 2008) also suggest that UVB can play an important role in the circulating concentrations of 25-hydroxyvitamin D 3 in these reptiles too. ...
... To date, the majority of the research evaluating the effects of UVB radiation on reptiles has focused on diurnal species (Allen et al., 1999;Laing and Fraser, 1999;Carman et al., 2000;Laing et al., 2001;Ferguson et al., 2003Ferguson et al., , 2005Acierno et al., 2006Acierno et al., , 2008Oonincx et al., 2010;Selleri and Di Girolamo, 2012). Although originally focused on lizards (Allen et al., 1999;Laing and Fraser, 1999;Carman et al., 2000;Laing et al., 2001;Ferguson et al., 2003Ferguson et al., , 2005Oonincx et al., 2010), more recent examples in chelonians (Acierno et al., 2006;Selleri and Di Girolamo, 2012) and a snake species (Acierno et al., 2008) also suggest that UVB can play an important role in the circulating concentrations of 25-hydroxyvitamin D 3 in these reptiles too. However, it should not be assumed that UVB light is a requirement for vitamin D regulation in all diurnal vertebrates, as dogs and cats do not use this method for acquiring vitamin D and a recent study in captive ball pythons (Python regius) found that UVB had no impact on circulating 25-hydroxyvitamin D 3 concentrations in that species (How et al., 1994;Hedley and Eatwell, 2013). ...
Article
Ultraviolet B radiation (UVB) is required by many vertebrates to stimulate the photobiochemical synthesis of vitamin D. Vitamin D plays many important roles in the body, including assisting in the absorption of calcium at the level of the intestines. Deficiencies in vitamin D can lead to the development of nutritional disease. Leopard geckos (Eublepharis macularius) are naturally nocturnal to crepuscular; therefore, it is not known whether they benefit from UVB radiation. The purpose of this study was to measure 25-hydroxyvitamin D3 concentrations in leopard geckos exposed to short duration UVB light. Twelve adult, male leopard geckos were used for this study. Blood samples were collected from the cranial vena cava to establish baseline 25-hydroxyvitamin D3 concentrations. Once the baseline samples were collected, the animals were randomly divided into two groups. The animals provided UVB radiation were exposed to non-UVB producing light for 12 h and UVB for 2 h, whereas animals in the control group only received non-UVB producing light for 12 h. Exposure to the UVB light occurred for 2 h per day: 1 h at 0600 h and 1 h at 1800 h to mimic dawn and dusk, respectively. An additional blood sample was collected 30 days after the initiation of UVB exposure. There was a significant difference (F = 9.7, P = 0.012) in 25-hydroxyvitamin D3 concentrations between the two groups, with UVB exposed geckos having significantly higher concentrations. The results of this study demonstrate that short duration exposure to UVB light can lead to increased circulating 25-hydroxyvitamin D3 concentrations in leopard geckos.
... during the heat of the day. The maximum solar UVb irradiance recorded at the location of one of the basking dragons was 506 μW/ cm 2 at 14.00.The UVb spectral irradiance of each of the five treatment lamps and the ZooMed lamp from the study byOonincx et al. (2010), F I G U R E 2 Bodyweight (BM), snout vent length (SVL) and total length (TL) of ~4-month-old bearded dragons (Pogona vitticeps) exposed to one control lamp and five UVb compact lamps. Different letters above bars represent significant differences (p < .05) ...
... The measured spectral irradiance (μW/cm²/nm) from each lamp was weighted with the CIE previtamin D 3 action spectrum(Bouillon et al., 2006) to obtain a comparison of their vitamin D 3 effective (D-Eff) irradiance. A previous experiment(Oonincx et al., 2010) had used similar experimental parameters with a different compact lamp. A comparison was made with the spectrum and D-Eff from this lamp (ZooMed Reptisun 5.0 UVb Tropical 26-watt, ZooMed Laboratories Inc., San Luis Obispo, USA) and with reference solar spectra from Australia(Bernhard, Mayer, Seckmeyer, & Moise, 1997). ...
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The effect of exposure to different UVb compact lamps on the vitamin D status of growing bearded dragons (Pogona vitticeps) was studied. Forty-two newly hatched bearded dragons (<24 h old) were allocated to six treatment groups (n = 7 per group). Five groups were exposed to different UVb compact lamps for two hours per day, with a control group not exposed to UVb radiation. At 120 days of age, blood samples were obtained and concentrations of 25(OH)D3 , Ca, P and uric acid were determined. In addition, plasma 25(OH)D3 concentration was determined in free-living adult bearded dragons to provide a reference level. Only one treatment resulted in elevated levels of 25(OH)D3 compared to the control group (41.0 ± 12.85 vs. 2.0 ± 0.0 nmol/L). All UVb-exposed groups had low 25(OH)D3 plasma levels compared to earlier studies on captive bearded dragons as well as in comparison with the free-living adult bearded dragons (409 ± 56 nmol/L). Spectral analysis indicated that all treatment lamps emitted UVb wavelengths effective for some cutaneous vitamin D synthesis. None of these lamps, under this regime, appeared to have provided a sufficient UVb dose to enable synthesis of plasma 25(OH)D3 levels similar to those of free-living bearded dragons in their native habitat.
... For a long time, insects were considered to contain low levels of vitamin D (typically <400 IU/kg DM) (Finke, 2002, Oonincx et al., 2010. However, data from three wild caught species indicated a high variability in its concentrations with values ranging from below the detection limit (100 IU vitamin D3/kg DM) up to 1,288 IU vitamin D3/kg DM (Finke, 2015b). ...
... However, regardless of the peaks' respective sizes all were quickly determined not to indicate vitamin D 3 via spectrum analysis. These findings are largely in accordance with published literature, in which levels of vitamin D 3 are either below the level of detection or samples are found to contain only small amounts (0.003-0.19 µg/g dry matter) of vitamin D 3 , presumably due to some exposure of the insect samples to sunlight before analysis (Finke, 2002(Finke, , 2015Mlcek et al., 2019;Oonincx et al., 2010). In contrast, the chromatograms of the UVB-treated mealworm samples clearly showed the formation of large peaks at this time point, indicating the formation of vitamin D 3 after the UVB-treatment. ...
... Тъй като брадатите агами са дневноактивни гущери, освен от източник на топлина в терариума, се нуждаят и от източник на UV-лъчение. Ултравиолетовият спектър е необходим, за да синтезират витамин ВЕТЕРИНАРНОМЕДИЦИНСКА ПРАКТИКА 5 -6/2023 45 D3 в кожата [15]. Типични признаци на развиващо се метаболитно заболяване на костите са размекването на челюстите с деформации в конфигурацията им, слабост и подувания в крайниците (фиброзна остеодистрофия), тремори, структурни изменения в лумбалните и опашните прешлени, фрактури тип "зелена пръчка" при дългите тръбести кости и загуба на телесна маса (фигура 2) [17,20]. ...
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Брадатите агами са вид гущери, които бързо се социализират, нямат агресивно поведение и са предпочитан нестандартен домашен любимец, набиращ все по-голяма популярност в България. Популяризирането на този вид гущери и все по-честият интерес на собствениците към тяхното отглеждане налага нови предизвикателства пред ветеринарните специалисти у нас по отношение често срещани здравословни проблеми, как те да бъдат правилно диагностицирани и лекувани, и какви профилактични мерки следва да бъдат приети, за гарантиране здравето и благополучието на отглежданите в домашни условия животни.
... Access to natural sunlight or highquality artificial lighting is generally agreed to be a critical factor for the health of many reptiles, in large part due to its importance in vitamin D 3 synthesis. Increased vitamin D 3 levels have been documented in various reptile species exposed to adequate UV light (Holick et al., 1995;Laing and Fraser, 1999;Carman et al., 2000;Ferguson et al., 2002;Acierno et al., 2008;Oonincx et al., 2010;Bos et al., 2018). Previous studies on a variety of chelonian species have demonstrated significantly higher vitamin D 3 concentrations in animals exposed to a UVB source. ...
... Access to natural sunlight or highquality artificial lighting is generally agreed to be a critical factor for the health of many reptiles, in large part due to its importance in vitamin D 3 synthesis. Increased vitamin D 3 levels have been documented in various reptile species exposed to adequate UV light (Holick et al., 1995;Laing and Fraser, 1999;Carman et al., 2000;Ferguson et al., 2002;Acierno et al., 2008;Oonincx et al., 2010;Bos et al., 2018). Previous studies on a variety of chelonian species have demonstrated significantly higher vitamin D 3 concentrations in animals exposed to a UVB source. ...
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Species specific physiology, seasonal changes, sex, and husbandry factors all influence the blood chemistry of chelonians, including vitamin D 3 , calcium, phosphate and magnesium levels. Problems in the supply of many of these are commonly seen in captive reptiles. The goal of this study was to measure vitamin D 3 , calcium, phosphate and magnesium in plasma from captive, healthy, adult Hermann’s tortoises ( Testudo hermanni ) and pond sliders ( Trachemys scripta ). Samples were categorized and compared based on species, sex, season, and access to sunlight as a central husbandry element. Blood samples of 522 Hermann’s tortoises and 188 pond sliders, taken from March to September 2022, were included in the study. New reference intervals for vitamin D 3 , calcium, phosphate and magnesium were established, with specific reference intervals calculated for each species, sex, and season in those cases in which significant differences were found based on these factors. For the calculation of reference intervals for vitamin D 3 the factors species, season and access to sunlight were considered. Vitamin D 3 levels differed by access to sunlight in some seasons depending on the species and were generally higher in Hermann’s tortoises. Plasma vitamin D 3 levels did not correlate with calcium, phosphorus or magnesium levels on a larger scale in either species. Calcium, phosphate, and magnesium were higher in females than in males of both species, and magnesium was higher in Hermann’s tortoises than in pond sliders. Our results can be helpful in a more specific interpretation of blood results and support previous findings that direct sunlight is an important factor in chelonian health. More studies are needed to better understand the role of other hormonal influence on the vitamin D 3 , calcium, phosphate and magnesium metabolism in chelonians.
... The extent to which reptiles use dietary D3 is not well understood and likely varies between species. There is evidence that veiled chameleons and tuatara (Sphenodon punctatus) can utilize dietary D3 and Texas spiny lizards (Sceloporus olivaceus) consume dietary sources of D3, 3,12,15 but juvenile bearded dragons had higher plasma concentrations of vitamin D metabolites when exposed to UVB light compared with bearded dragons with no UVB exposure fed dietary D3. 20 In juvenile C. calyptratus, hepatic 25OHD3 was highest when the chameleons were supplemented with Ca, vitamin A, D3, and UVB. 12 Dietary D3 supplementation is recommended for ECL in human care. 17 It is recommended to feed ECL daily but only dust with Ca and D3 two to three times per week. ...
Article
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Vitamin and mineral supplements are commonly used in diets for zoologic and companion animals. Because specific nutrient requirements are often unknown, informed decisions are based on literature for related species. Over 18 mon beginning in November 2017, an entire population of spot-tailed earless lizards (Holbrookia lacerata and Holbrookia subcaudalis) died (N = 33). All but two lizards were submitted for histopathology (94%). All examined cases had mineralization in at least one tissue; 71% (22 of 31) had multisystemic mineral deposits consistent with metastatic mineralization. No underlying causes were detected histologically. The supplement used for dusting the food items fed five to six times per week was inadvertently switched for 2 to 4 mon, and the incorrect supplement was found to contain fourfold the intended vitamin D3 concentration. Thus, hypervitaminosis D was considered the most likely cause. Interestingly, eastern collared lizards (Crotaphytus collaris), also fed prey supplemented five to six times a week, and over 50 other insectivorous reptile and amphibian species possibly receiving the supplement one to seven times a week did not appear affected. During this time, only two other cases of metastatic mineralization were diagnosed in other herpetofauna at this institution. Prior to receiving the incorrect supplement, there were no cases of metastatic mineralization detected in the earless lizard population. These cases highlight species-specific sensitivities, and the deleterious effects of excessive or inappropriate supplementation. It is important to confirm product identification on arrival, regularly conduct chemical analysis of supplements, and educate keepers and owners about adverse effects of inappropriate supplementation.
... This mechanism would entail Bearded Dragons using changes in their vitamin D status to indirectly detect the UV light irradiance of their current environment and modify their behavior accordingly (Ferguson et al., 2003). Our husbandry methods for the animals in this study were adequate to maintain their vitamin D status (Oonincx et al., 2010); therefore, they were not vitamin D stressed. As their bodies had adequate vitamin D 3 concentrations, no additional vitamin D 3 was produced cutaneously when they were in the UV light irradiance gradient apparatus. ...
Article
Exposure to ultraviolet (UV) light has both physiological benefits as well as costs. Many lepidosaur reptiles can behaviorally self-regulate their exposure to UV light in order to take advantage of the benefits of UV light while minimizing the costs. Furthermore, lepidosaur scales have been conceptualized by some as a barrier to the penetration of UV light. Here we examine regulation of self-exposure to UV light in three different phenotypes of Bearded Dragon (Pogona vitticeps): wild type, animals exhibiting scales of reduced prominence (‘Leatherback’), and scaleless animals (‘Silkback’). Silkbacks on average chose to expose themselves to lower levels of UV light irradiation than Leatherbacks or wild types did. Bearded Dragons of all scalation phenotypes on average received higher UV irradiation when they were in the cold section of a UV gradient apparatus compared to when they were in the hot section of the apparatus. This either demonstrates that Bearded Dragons under higher UV irradiances choose cooler temperatures or demonstrates that Bearded Dragons at cooler temperatures choose higher UV irradiances. The relationship between chosen temperature and chosen UV light irradiance was not affected by scalation phenotype. This study highlights external influences on the mechanism that regulates UV self-exposure behavior in lepidosaur reptiles.
... CLIA determination of total 25(OH)D assay does not discriminate between 25-hydroxyvitamin D 2 and 25hydroxyvitamin D 3 , nor can the assay discriminate between the vitamin D 3 obtained by basking and from the diet. Indeed, in natural populations of herbivorous reptiles, UV exposure rather than diet plays the most critical role in determining vitamin D levels [17,31]. Additionally, D 2 supplementation is not as effective as D 3 supplementation in raising plasma 25(OH)D levels in humans [32]. ...
Article
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We report the first data on 25-hydroxyvitamin D plasma levels in natural populations of three species of land iguana endemic to the Galápagos Islands (Conolophus marthae, C. subcristatus, and C. pallidus). The pigment is present throughout the whole body in the skin of C. subcristatus and C. pallidus. On the contrary, pigment is not present in the skin of an extended part of the body in C. marthae. The only existing population of C. marthae is syntopic with a population of C. subcristatus, and the two species are closely related. These circumstances would suggest that, under the assumption that the species show a similar basking behavior and in the absence of compensatory mechanisms, lighter pigmentation should favor higher vitamin D levels. Thus, C. marthae, compared with C. subcristatus in Wolf Volcano, could show higher levels of 25(OH)D plasma levels, or equal, if compensatory mechanisms exist. The three species showed levels in the range of average values for healthy iguanas. However, contrary to the expectation, C. marthae consistently exhibited the lowest 25(OH)D plasma levels. We discuss possible factors affecting vitamin concentration and hypothesize that C. marthae may use the habitat to limit exposure to the high UVB irradiation at Wolf Volcano.
... The majority of owners provided calcium with vitamin D 3 , a finding that is consistent with the literature (Raiti, 2012;Boyer and Scott, 2019a). This recommendation is not evidence based for bearded dragons because the only study completed thus far on this topic indicated that oral supplementation of vitamin D 3 was ineffective at increasing plasma calcidiol and calcitriol concentrations compared with 2 h of UVB exposure (Oonincx et al., 2010). These diurnal animals should be able to synthetize their own endogenous vitamin D 3 through sufficient UVB, and almost all survey respondents provided UVB for their bearded dragons. ...
Article
Nutrition is an important aspect of inland bearded dragon ( Pogona vitticeps) health and improper diet is thought to be a predisposing factor for many health disorders. The objective of this study was to survey bearded dragon owners to learn more about their feeding practices and supplement use. Self-selecting bearded dragon owners were invited to participate in the survey if they were over 18 years of age or had guardian consent and resided in Canada or the United States. A survey titled “Nutritional Survey of Bearded Dragon Dietary Habits in North America” was available online following research ethics board approval from the University of Guelph. A total of 405 responses representing sub-adult and adult bearded dragons were evaluated. The most common diet offered consisted of one to 25% larval and adult insects, each, and 51 to 75% plant material. Approximately half of the survey participants, especially the younger respondents, were feeding diets with less than 50% plant material and more than 50% insects. Berries were the most common plant material offered, while superworms (Zophobas morio) and hornworms ( Manduca sexta) were the most common larval insects offered, and house crickets ( Acheta domesticus) were the most common adult insects offered. Insects were commonly dusted with calcium, vitamin D 3 and multivitamins, but plant materials were not dusted. These results highlighted the requirment for the development of clear nutritional guidelines outlining the type, quantity, and frequency of food items and supplements offered, and the requirement of further investigations to determine the.....
... Although lizards can also obtain vitamin D 3 via ingestion, efficacy of increasing the circulating concentration of vitamin D 3 is far superior with solar UV exposure (Acierno et al., 2006;Oonincx et al., 2010). ...
Article
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Over a century of ecophysiological studies on lizards have perpetuated the assumption that basking and shuttling movements between sun and shade function solely for temperature regulation. However, these behaviours also modulate exposure to ultraviolet (UV) wavelengths that are essential for maintaining physiological homoeostasis as well as ensuring proper growth and development and enhancing long‐term fitness. An alternative hypothesis is that lizards also actively regulate their UV exposure. In this scenario, UV needs may even override temperature needs (or vice versa), generating asymmetries in the ability of a lizard to regulate both conditions equally. We test this hypothesis using field and laboratory data collected on adult Sceloporus undulatus. We found that S. undulatus actively regulate UV exposure and prioritize UV over temperature, favouring body temperatures much higher than preferred values to sustain preferred UV exposure. In stark contrast, temperature had no reciprocal impact on UV regulation behaviour. Our field data support these patterns, suggesting that lizards may even seek out hotter environments despite thermal costs to enhance UV exposure. We conclude that S. undulatus actively regulate for UV as well as temperature. Unfortunately, outside of zoos and private hobbyists, appreciation of the importance of UV for ectotherm survival and reproductive success has been minimal. Addressing this deficit will therefore be vital to improve our understanding of the factors shaping the evolution of ectotherm photoregulation behaviour in nature. Read the free Plain Language Summary for this article on the Journal blog.
... However,Rhine et al. (1986) observed eggs being consumed by P. cynocephalus at Mukumi National Park, which may indicate a prominent dietary source of vitamin D. Finally, insects are sometimes included in baboon diets, as observed in locust and dragonfly consumption by P. cynocephalus and P. hamadryas troops(Rhine et al., 1986;Schreier et al., 2019). Locusts, along with a subset of other insect taxa, have an especially high vitamin D 3 content for body size(Oonincx et al., 2010).The primary limitations of this study are the low availability of postcranial remains, which may have aided MBD identification in younger individuals, and incomplete documentation of the life history of the animals in the sample. Furthermore, there are many aspects of the captive experience that are critical to the story of the captive animal. ...
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Objectives To assess manifestations of metabolic bone disease (MBD) and their potential environmental and phenotypic factors in captive and non-captive baboon (Papio spp.) specimens. Materials and methods Our sample consisted of 160 baboon specimens at the Smithsonian's National Museum of Natural History accessioned from 1890 to 1971. Combining cranial indicators of MBD and the museum's historical data, we examined factors contributing to likely instances of MBD. We used binomial-family generalized linear models to assess differences in MBD frequency by environment (captive, non-captive), specimen accession year, and skin color (light, medium, dark). Results Indicators of MBD were most frequently observed in captive baboons, with a decrease in MBD frequency over time. Fifteen non-captive individuals showed indicators of MBD, which are the first published cases of MBD in non-captive nonhuman primates (NHPs) to our knowledge. The most common MBD indicators were bone porosity (n = 35) and bone thickening/enlargement (n = 35). Fibrous osteodystrophy was observed frequently in our sample, likely relating to nutritional deficiencies. We found no association between exposed facial skin color variation and MBD. Conclusions Our findings are consistent with historical accounts of MBD prevalence in captive facilities, especially earlier in the 20th century. A decrease in MBD prevalence later in the 20th century likely reflects improvements in housing, diet, and veterinary care in captive settings. Causes of MBD development in non-captive baboons should be further explored, as understanding the potential health impacts that anthropogenic environments impose on NHPs is imperative as humans increasingly alter the natural world in the 21st century.
... For a long time, insects were considered to contain low levels of vitamin D (typically <400 IU/kg DM) (Finke, 2002, Oonincx et al., 2010. However, data from three wild caught species indicated a high variability in its concentrations with values ranging from below the detection limit (100 IU vitamin D3/kg DM) up to 1,288 IU vitamin D3/kg DM (Finke, 2015b). ...
Article
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This article reports on the nutrients present in insects and factors affecting their variability. Data on protein content and amino acid profiles of a variety of insect species are discussed and their amino acid profiles compared to nutrient requirements of growing broiler chicks, catfish, trout, swine, and human adults and young children. Both in vitro and in vivo protein digestibility data for a variety of insect species is presented and factors affecting these data are discussed. Furthermore, the fat content and fatty acid profiles of a variety of insect species is reviewed, with special attention on omega-6 and omega-3 fatty acids. Information on carbohydrates, fibre and chitin in insects is shown along with potential effects on nutrient availability. This is followed by a discussion of essential minerals in insects with an emphasis on calcium and phosphorus. Data on insect vitamin content is shown along with a discussion of antinutritional factors such as phytate and thiaminase, which can adversely affect their nutritional value. Dietary effects on insect nutrient composition are reviewed with an emphasis on essential minerals, heavy metals, vitamin E, and carotenoids. Lastly, the effects of processing, including protein extraction and various cooking methods on insect composition are discussed. In summary, this article provides an overview of the nutrient content of insects, and how select nutrients can be altered.
... The most common of these syndromes in captive reptiles is nutritional secondary hyperparathyroidism, which occurs with a deficiency in either calcium or vitamin D 3 , improper calcium to phosphorus ratio or an inadequate exposure to proper ultraviolet radiation. [5][6][7][8][9] When any of these husbandry deficiencies exist, a physiological hypocalcaemia may result. ...
Article
Carnivorous reptiles are not usually thought of as being prone to metabolic bone disorders. A constant diet lacking in calcium or bone and/or high in phosphorus or low in vitamin D3 can lead to this nutritional disorder in certain situations. Nile monitor lizards are carnivorous lizards native to Africa and common in the pet trade and as display animals in zoos. They normally consume whole vertebrate prey but will readily take muscle and organ offerings. This is a case of a Nile monitor that suffered fibrous osteodystrophy and chondroid metaplasia after being fed mostly muscle tissue for over two years. Once the diet was corrected the clinical signs resolved.
... A kültéri terráriumot az állattartók jelentős része nem tudja biztosítani -ill. nem is minden faj esetében megoldható -ezért a természetes napfény alternatívájaként jól használhatók az UV-B-lámpák (1,2,3,7,8,22). 1 company, 2 category, 3 "desert", 4 "tropical", 5 output, 6 bulb identifier "Trópusi" és "sivatagi" életmódú hüllőknek javasolt izzókat, valamint egy hőt is kibocsátó terméket vizsgáltak ...
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ÖSSZEFOGLALÁS A szerzők jelen vizsgálatukban bemutatják a mesterséges UV-B-izzók (n = 9) sugárzási értékeinek alakulását az idő és az izzótól mért távolság függvényé-ben. A hüllők metabolikus csontbetegségének egyik megelőzési lehetősége a mesterséges UV-B-sugárzás biztosítása. A méréseket hét hetes időközökkel, hét alkalommal végezték el, mindegyik gyártó (n = 3) egy éves élettartamot garan-tált. Az összes izzó esetében a 2. méréskor (7. hét) az eredetihez képest 30−35%-os, ill. a 3. méréskor (14. hét) 50% körüli sugárzás csökkenést mértek. Mindezek miatt − amennyiben nincs lehetőség a sugárzási szint rendszeres ellenőrzésére-javasolt 3−4 hónap után cserélni az izzókat. SUMMARY Background Metabolic bone disease (MBD) is considered the most prevalent disease of reptiles in captivity. The lack of cholecalciferol in the diet and/or the lack of suitable UV-B-light (natural or artificial form) are the most important causes (nutritional MBD). Objectives: The authors of this study investigated commercially available ultraviolet-B (UV-B) bulbs of three popular companies’. Bulbs were divided into two categories “tropical” and “desert” according to the target species. Materials and Methods The bulbs were placed individually into plastic terrariums which were covered with thick black foil. The level of UV-B irradiation of 9 different compact bulbs was measured over distance and time. Measurements were made 7 times with 7 week differences with Solartech 6.2 UV meter with a distance of 10, 20, 30 and 40 cm from the surface of the bulb. One company’s products had significantly lower irradiation − despite the same outputs − even at the beginning of the study (ANOVA test, p<0.05). Results and Discussion However all products had a lifespan of 1 year according to the label information, two “desert” and one “tropical” bulb had a very low level of irradiation at the 4. measurement (28. week, 20 cm). According to the results all of the bulbs lost 30-35% of their irradiation level compared to starting levels at the time of the 2nd measuring (7th week), which was only 50% at the time of the 3rd measurement (14th week). Because of this – if regular control of the irradiation is not possible – changing of the bulbs in every 3-4 months is recommended. As the irradiation of the 13W bulb was low even at the beginning, this seems to be less adequate for desert species. Bulb with similar W outputs may have different level of UV-B irradiations; accordingly it is advised to regularly control the level of emission.
... De novo synthesis requires exposure of a vitamin D precursor to ultraviolet light with a wavelength between 280 and 320 nm (UVb), followed by a temperature dependent step 6,7 . Humans, birds, reptiles, amphibians and fish can use both strategies, although de novo synthesis seems the primary route to acquire a sufficient vitamin D status [8][9][10][11] . Ergosterol is the primary vitamin D precursor in plants, yeasts and fungi, which UVb light converts to vitamin D 2 , whereas 7-dehydrocholesterol (7DHC) is the precursor which forms vitamin D 3 in vertebrates 12,13 . ...
Article
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Vertebrates obtain the prohormone vitamin D primarily by endogenous cutaneous synthesis under ultraviolet b (UVb) exposure. To date, endogenous synthesis of vitamin D in insects has never been investigated. In an initial experiment, we exposed four insect species which differ in ecology and morphology (migratory locusts, house crickets, yellow mealworms and black soldier fly larvae (BSFL)) to a low irradiance UVb source. In a second experiment we exposed these species to a higher UV irradiance, and in a third we tested the effect of exposure duration on vitamin D concentrations in yellow mealworms. Low irradiance UVb tended to increase vitamin D3 levels in house crickets, vitamin D2 levels in BSFL and vitamin D2 and D3 in yellow mealworms. Higher UVb irradiance increased vitamin D3 levels in all species but BSFL. Both BSFL and migratory locusts had increased vitamin D2 levels. Longer UVb exposure of yellow mealworms increased vitamin D2 and increased vitamin D3 until a plateau was reached at 6400 IU/kg. This study shows that insects can synthesize vitamin D de novo and that the amounts depend on UVb irradiance and exposure duration.
... The absence of metabolic bone disease symptoms it is also a good marker to highlight the role of UV-B rays provision in Calcium metabolism (Mans, 2013): for example, in Bearded Dragons, exposure to UV-B seems to be the primary method to attain a sufficient vitamin D status (Oonincx et al, 2010). Incorrect ultraviolet lighting may cause serious problems such as metabolic bone disease, but also basal cell generation, epidermal necrosis, and keratoconjunctivitis (Gardiner et al, 2009). ...
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The role of a well-executed physical examination performed by a veterinary doctor in captive reptiles is considered to be an easy and non-invasive way to assess the general health status of those animals, expecially in big collections. The study used this clinical investigation on 60 captive reptiles present at "The National Reptile Zoo" in Gowran (34 Lizards, 13 Snakes and 13 Chelonians from 27 different species from different habitats and continents) to have an overview and classify the most common findings and their connection with the environmental conditions of the enclosures. The clinical examination included a complete history and anamnesis data collection, an hands-off part where the individual was observed and a hands-on part which included manipulation, followed by a general conditions assessment. The results show a prevalence of integumentary system clinical findings in all groups (58,3%), with the presence of wounds or superficial lesions as the first clinical finding (28,3%). This highlights the role of the integument as the most sensible system, as well as one of the easiest to examine. Compared to Chelonians and Snakes, Lizards had a higher prevalence of musculoskeletal system findings (58,8%). The results show as well that clinical finding are not always correlated to a disorder, as the majority of the examined inviduals (65%) was considered healthy. The focus on environmental conditions shows the importance of a correct enclosure management in reptiles, and the potential correlation of a wrong aproach with clinical findings such as dysecdysis and missing toes, while the absence of other symptoms, such as thermal burns, preys bites or metabolic bone disease, can indicate a correct management of some environmental aspects. AKNOWLEDGEMENTS The author wish to thank all “The National Reptile Zoo” staff (Dr.Joana Santos, Dr. Hope Daly, Dr. Tara Cullen and Christina Hogan) for helping on training, data collection and the general support for this work. Zoo director James Hennessy played a crucial role for the completion of the project by reviewing drafts and helping on data analysis.
... Data on vitamin D in insects are limited. Most commercial insects contain low levels of vitamin D (typically <400 IU/kg dry matter ;Finke, 2002Finke, , 2013Oonincx et al., 2010). Data from three wild caught species were highly variable with values ranging from undetectable (<100 IU vitamin D3/kg dry matter) to 1,288 IU vitamin D3/kg dry matter (Finke, 2015b). ...
Article
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UVB lamps are used to provide reptiles housed indoors with the UV radiation necessary to synthesize vitamin D3 in their skin. Since 2019, UVB-LED lamps have been on sale for use in reptile husbandry. We performed spectral analysis and mapped the UV irradiance for 18 of these lamps. The positive benefits of UVB-LED lamps over traditional products include greater energy efficiency, freedom from mercury and easy installation without external ballasts. However, the spectra of all the UVB-LED lamps tested had little similarity to the solar UV spectrum. Some lamps emitted short-wavelength, non-terrestrial, radiation known to cause acute photo-kerato-conjunctivitis; we report one case. All lamps were lacking significant output in the range 315–335 nm, essential for natural self-regulation of cutaneous vitamin D3 synthesis, preventing overproduction. We describe a possible risk of serious hypervitaminosis D based on our spectral analysis. We call for long-term animal studies to assess this risk, in which the reptiles under these lamps are exposed to species-appropriate UV index levels according to their Ferguson Zone allocation and serum levels of vitamin D3 and 25(OH)D3 monitored. Spectral modifications of the lamps to make the spectrum more like sunlight may be an essential way of mitigating this risk.
Article
Insectivores are represented in virtually all taxa, although more is known about mammalian and avian insectivore nutrition than for reptiles, amphibia and fish. Establishing nutrient requirements is challenging but recommendations should be based on data from similar taxa, similar GI tract physiology, and known nutritional concerns. In order to provide an appropriate diet for insectivores, consideration must be given to anatomy and method for procuring insects in free-ranging habitats, availability of feeder insects and the resulting dietary nutrient profiles, and complementing those profiles with appropriate diet items from various other categories including formulated feed, produce, animal matter, seeds or grains etc. Consideration of known nutritional concerns for a given species, and the variation in energy requirements in a captively managed situation are essential.
Chapter
Appropriate nutritional husbandry for captive reptiles is inherently challenging. The health and welfare of all reptiles, like any other animals, is linked to the role of nutrition, which should be regarded as a continuum, beginning with selection or gathering of food sources and ending with elimination of waste products. Reptiles have evolved to represent all known foraging strategies, and the various alimentary tract morphologies exemplify this complexity. Many reptiles have long life spans and, possibly more so than other taxa, can be outwardly very forgiving of short-term nutritional mismanagement resulting in compromised long-term health. Because nutrition is complex and does not happen in a vacuum, often the impacts of correct and incorrect provisions get lost in a myriad of variables that contribute positively and negatively to the overall health of captive reptiles. Quality of diet and appropriate mode of presentation are essential to health, and natural foods are preferable. This chapter will provide detail about how reptiles acquire and process food items and to what end (what are the target nutrient levels met by a reasonable, appropriate diet). Furthermore, this chapter presents some of the challenging factors associated with nutritional husbandry of reptiles in a managed setting—provision of appropriate moisture and/or UV light, selection of specific diet ingredients, and what do we still need to learn.KeywordsApprehensionDigestionAssimilationEliminationDietNutrition principlesTarget nutrientsLightHealthDiseaseInjuryStressTreatment
Chapter
A variety of commercially raised insect species are commonly fed to captive insectivores. We review their nutrient content and compare those values to the data available for wild-caught insects. These data are discussed in light of the nutrient requirements for domestic animals to identify nutrients of concern for captive insectivores. Additionally, various environmental and dietary factors which can significantly affect insect nutrient composition are reviewed. We then evaluate the various techniques that are currently used to enhance the nutrient content of commercially bred insects including gut loading, dusting and modifying the composition of the insect through dietary changes. Lastly possible safety considerations including pathogens, pathogenic microorganisms, toxins, and antinutritional factors that might be important factors when feeding captive insectivores are discussed.
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Test of a commercial fluorescent lamp with UVA phosphor
Conference Paper
Ecology of the central bearded dragon (Pogona vitticeps) - Basking temperatures, Ultraviolet Index , humidity, diet, weight. length, reproduction, brumation and lifespan.
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African tortoises comprise a wide range of species with some overlap with Mediterranean species. This chapter focuses on those distinct species found only in Africa. It describes the types of tortoises such as spur‐thighed tortoises, sulcata tortoise, leopard tortoise, African hingeback tortoises, Aldabran tortoises, and pancake tortoise. Spur‐thighed tortoises of North African origin, if hibernated at all, require a shorter hibernation period than their Mediterranean counterparts. It is recommended that they do not hibernate longer than 8–10weeks, even in mature individuals, as opposed to the recommended 12 weeks with all other healthy Mediterranean species. For clinical evaluation, the chapter includes history‐taking, handling, sex determination, and clinical examination. It discusses the basic techniques including sample collection, nutritional support, fluid therapy, anaesthesia, analgesia, euthanasia, and hospitalisation. The chapter also discusses common medical and surgical conditions, preventative health measures, and radiographic imaging in the tortoises.
Chapter
This chapter provides a nutritional primer for wildlife professionals raising nestlings of species that, in the wild, would be fed predominantly insects or other arthropods. The insect species most commonly cultured for food include house crickets, waxworms, mealworms and superworms, soldier flies, fruit flies and several species of roaches. As the primary food for many wild nestlings, insects in general should supply adequate levels of protein, amino acids, fatty acids, plus most minerals and vitamins. Assuming an adequate supply of foodstuffs, wild birds are presumably able to select a variety of arthropods that, in the proper proportions, provides nestlings a diet that is sufficient for growth. Cultured insects presumably offer a close approximation to the natural diet of insectivorous nestlings; however, they are expensive, and supplementing them with appropriate amounts of selected nutrients can be challenging.
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Female Carpetan rock lizards (Iberolacerta cyreni) might assess the quality of males from their chemical signals. Females select areas scent marked by males with secretions containing high proportions of provitamin D to ensure mating with high-quality males. However, an alternative explanation might be that females are not choosing a mate, but that females have a pre-sensory bias for chemical cues of vitamin D in the food and are, in fact, assessing habitat quality to obtain direct benefits of increasing the intake of vitamin D. We evaluated experimentally the possible benefits of a nutritional supplement of provitamin D or vitamin D in pregnant females for their clutches and offspring. However, we did not find large differences between treatments, except in the lower body condition of juveniles of mothers supplemented with provitamin D. We also tested the chemosensory interest of females in the scent of males to study the existence of a sensory bias; this response decreased when the amount of dietary vitamin D exceeded their needs. The results suggest that there are no reproductive benefits in the intake of additional vitamin D and that the potential sensory bias to scents of males could be related to the physiological needs of the females.
Chapter
The provision of a good light source is important for reptiles. For instance, ultraviolet light is used in social interactions and used for vitamin D synthesis. With respect to housing, most reptilians are best kept pairwise or individually. Environmental enrichment can be effective but depends on the form and the species to which it is applied. Temperature gradients around preferred body temperatures allow accurate thermoregulation, which is essential for reptiles. Natural distributions indicate suitable ambient temperatures, but microclimatic conditions are at least as important. Because the nutrient requirements of reptiles are largely unknown, facilitating self-selection from various dietary items is preferable.
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A large part of the environmental impact of animal production systems is due to the production of feed. Insects are suggested to efficiently convert feed to body mass and might therefore form a more sustainable food and/or feed source. Four diets were composed from by-products of food manufacturing and formulated such as to vary in protein and fat content. These were offered to newly hatched Argentinean cockroaches, black soldier flies, yellow mealworms, and house crickets. The first two species are potentially interesting as a feed ingredient, while the latter two are considered edible for humans. Feed conversion efficiency, survival, development time, as well as chemical composition (nitrogen, phosphorus, and fatty acids), were determined. The Argentinean cockroaches and the black soldier flies converted feed more efficiently than yellow mealworms, and house crickets. The first two were also more efficient than conventional production animals. On three of the four diets yellow mealworms and house crickets had a feed conversion efficiency similar to pigs. Furthermore, on the most suitable diet, they converted their feed as efficiently as poultry, when corrected for edible portion. All four species had a higher nitrogen-efficiency than conventional production animals, when corrected for edible portion. Offering carrots to yellow mealworms increased dry matter- and nitrogen-efficiency and decreased development time. Diet affected survival in all species but black soldier flies, and development time was strongly influenced in all four species. The chemical composition of Argentinean cockroaches was highly variable between diets, for black soldier flies it remained similar. The investigated species can be considered efficient production animals when suitable diets are provided. Hence, they could form a sustainable alternative to conventional production animals as a source of feed or food.
Article
Insects serve as a major source of nutrients for many animal species, but complete nutritional information of wild insects is lacking. Wild pallid-winged grasshoppers, rhinoceros beetles and white-lined sphinx moths were caught in Rio Verde, Arizona, in the summer of 2013 (grasshoppers and beetle) or the spring of 2015 (moths). Pallid-winged grasshoppers, rhinoceros beetles and white-lined sphinx moths were analysed for moisture, crude protein, fat, ash, acid detergent fibre, minerals, amino acids, fatty acids and vitamins and values compared the nutrient requirements for both rats and poultry as reported by the National Research Council (NRC). The acid detergent fibre was also analysed for nitrogen. When compared to the nutrient requirements as established by the NRC for growing rats, grasshoppers were deficient in calcium, vitamin A, vitamin D, thiamine and vitamin B12, beetles were deficient in calcium, vitamin A, vitamin E, thiamine, pyridoxine and linoleic acid and moths were deficient in calcium, so...
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The opportunity and ability to photobiosynthesize vitamin D3 by exposing skin to ultraviolet-B (UVB) irradiation from the sun was compared using the nocturnal/crepuscular Mediterranean House Gecko Hemidactylus turcicus and the diurnal Texas Spiny Lizard Sceloporus olivaceous. Texas spiny lizards had a greater opportunity for photobiosynthetic production of vitamin D3 than geckos. This was revealed by vitamin D3 photoproduct production in models (ampoules containing an alcohol solution of vitamin D3 precursor) placed at locations inhabited by free-living lizards at similar times of occupancy. Alternatively, geckos seemed able to maximize their limited photobiosynthetic opportunity with a higher rate of conversion of provitamin D3 to photoproducts. This was revealed by photoproduct conversion in patches of lizard skin exposed to ultraviolet lamps in the laboratory. Stomach-content analysis showed the spiny lizards to have dietary sources of vitamin D3, the geckos may or may not. This is the first documentation that mostly nocturnal geckos may rely on photobiosynthesis of vitamin D3 and that they might have a more sensitive mechanism than diurnal lizards to compensate for their limited exposure to natural UVB radiation. Future studies should investigate sexual, seasonal, age, and species differences in photobiosynthetic opportunity and ability.
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The apparent plasma concentration of vitamin D binding protein (DBP) in an iguanian lizard, Pogona barbata, and the affinity of this protein for 25-hydroxyvitamin D3 (25(OH)D3), 25-hydroxyvitamin D2 (25(OH)D2), and 1,25-dihydroxyvitamin D3 (1,25(OH)D3) was found to resemble more closely that of the domestic hen than that of the human. The characteristics of Pogona DBP, the pattern of vitamin D metabolites derived from injected radioactive vitamin D3 and the plasma concentrations of endogenous 25-hydroxyvitamin D (25(OH)D) in a range of iguanian lizards have been examined. The findings suggest that 25-hydroxyvitamin D (25(OH)D) is the major metabolite of vitamin D, and that it may represent the storage form of vitamin D in these species in the same way as in mammals. High concentrations of vitamin D within iguanian embryos and egg yolks suggest a role for this compound in embryogenesis in these species, and perhaps indicates that there is a mechanism for vitamin D delivery to eggs comparable to that found in the domestic chicken.
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Seventy-two serum samples were collected from 14 healthy African elephants (Loxodonta africana), including three calves, to test for 25-hydroxyvitamin D [25(OH)D] as well as for performing biochemical panels. Samples were collected between July 1997 and January 2008 to establish normal 25(OH)D values for the species and to examine the relationship of season and time on these values. Although the number of samples from the calves was small (n = 7), there was no statistically significant difference in the mean 25(OH)D levels between adults and calves (15.7 +/- 7.7 ng/ml versus 17.1 +/- 5.8 ng/ml, P > 0.05, respectively). The comparison of mean and individual values among seasons showed some variation, but was not statistically different; therefore, all values were combined for further analyses. The mean value of 25(OH)D for all samples was 15.8 +/- 7.5 ng/ml (n = 72), with a 95% confidence interval of 14.0-17.6 ng/ml. There did not appear to be a direct correlation between 25(OH)D levels and calcium (Ca), phosphorus (P), or calcium:phosphorus ratio (Ca:P) based on regression analyses (P < 0.05). Values measured approximated normal distributions. Mean calcium value was 10.5 +/- 0.6 mg/dl (n = 61); mean phosphorus value was 5.2 +/- 0.8 mg/dl (n = 50); and mean Ca:P was 2.06 +/- 0.34. Since all animals appeared healthy during the course of sample collection, and bone density on foot radiographs was assessed as good, the results are considered to be normal for this herd. With the incidence of joint disease in older elephants, and metabolic bone disease in hand-reared calves, these values will provide a basis for further studies of calcium metabolism in elephants.
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The Komodo dragon (Varanus komodoensis) is the largest living lizard and occupies a range smaller than that of any other large carnivore in the world. Samples from 33 free-ranging animals at five localities in Komodo National Park, Indonesia were evaluated to assess underlying health problems. To build a comparative database, samples from 44 Komodo dragons in both Indonesian and U.S. zoos were also analyzed. Tests performed included complete blood counts, clinical chemistry profiles, vitamin A, D(3), and E analyses, mineral levels, and screening for chlorinated pesticides or other toxins in wild specimens. Blood samples from wild dragons were positive for hemogregarines, whereas captive specimens were all negative. Total white blood cell counts were consistently higher in captive Komodo dragons than in wild specimens. Reference intervals were established for some chemistry analytes, and values obtained from different groups were compared. Vitamin A and E ranges were established. Vitamin D(3) levels were significantly different in Komodo dragons kept in captive, indoor exhibits versus those with daily ultraviolet-B exposure, whether captive or wild specimens. Corrective measures such as ultraviolet-permeable skylights, direct sunlight exposure, and self-ballasted mercury vapor ultraviolet lamps increased vitamin D(3) concentrations in four dragons to levels comparable with wild specimens. Toxicology results were negative except for background-level chlorinated pesticide residues. The results indicate no notable medical, nutritional, or toxic problems in the wild Komodo dragon population. Problems in captive specimens may relate to, and can be corrected by, husbandry measures such as regular ultraviolet-B exposure. Zoo Biol 19:495-509, 2000. Copyright 2000 Wiley-Liss, Inc.
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Serum concentrations of several nutrients were measured in 12 captive wild felid species including caracal (Felis caracal), cheetah (Acinonyx jubatus), cougar (Felis concolor), fishing cat (Felis viverrinus), leopard (Panthera pardus), lion (Panthera leo), ocelot (Felis pardalis), pallas cat (Felis manul), sand cat (Felis margarita), serval (Felis serval), snow leopard (Panthera uncia) and tiger (Panthera tigris). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens and North Carolina Zoological Park). The nutritional composition of the diets at each institution met the probable dietary requirements for each species except for the pallas cat. Blood samples were collected from each animal (n = 69) and analyzed for lipids (total cholesterol, triacylglycerides, HDL cholesterol and LDL cholesterol), vitamin D metabolites [25-hydroxycholecalciferol (25(OH)D) and 1,25-dihydroxycholecalciferol (1,25(OH)(2)D)], vitamin A (retinol, retinyl stearate and retinyl palmitate), vitamin E (alpha- and gamma-tocopherol) and selected carotenoids. Species differences were found for all except triacylglycerides and 1,25(OH)(2)D. Genus differences were found for retinol, retinyl palmitate, retinyl stearate, gamma-tocopherol and beta-carotene. Circulating nutrient concentrations for many of the species in this study have not been reported previously and most have not been compared with the animals' dietary intakes. The large number of animals analyzed provides a substantial base for comparing the serum nutrient concentrations of healthy animals, for both wild and captive exotic species.
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Basking by ectothermic vertebrates is thought to have evolved for thermoregulation. However, another beneficial effect of sunlight exposure, specifically the ultraviolet B (UV-B) component, includes endogenous production of vitamin D(3). In the laboratory, panther chameleons exhibited a positive phototaxis to greater visible, ultraviolet A (UV-A) and UV-B light. However, with equivalent high irradiances of UV-A or UV-B, their response to UV-B was significantly greater than it was to UV-A. Exposure of in vitro skin patches of panther chameleons to high UV-B (90 microW/cm(2)) for 1 h significantly enhanced vitamin D(3) concentration. Voluntary exposure to higher UV-B irradiance (70 vs. 1 microW/cm(2)) resulted in greater circulating 25-hydroxyvitamin D(3) in female panther chameleons (604 vs. 92 ng/mL). Depending on dietary intake of vitamin D(3), chameleons adjusted their exposure time to UV-B irradiation as if regulating their endogenous production of this vital hormone. When dietary intake was low (1-3 IU/g), they exposed themselves to significantly more UV-producing light; when intake was high (9-129 IU/g), they exposed themselves to less. Vitamin D(3) photoregulation seems to be an important additional component of the function of basking.
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To investigate possible causes of embryonic and neonatal mortality in a group of captive Fijian iguanas (Brachylophus fasciatus and Brachylophus vitiensis), the vitamin D status of adults in the colony was compared with that of agamid and iguanid lizards either housed in indoor enclosures under artificial ultraviolet light or exposed to natural sunlight (wild-caught or captive animals housed outdoors). Those under artificial lighting had a significantly lower vitamin D status than those housed exclusively outdoors, whereas the vitamin D status of Fijian iguanas that had received intermittent exposure to natural sunlight was intermediate and not significantly different from that of animals housed exclusively outdoors. However, eggs from some of these Fijian iguanas had substantially lower vitamin D content than eggs from outdoor iguanid and agamid animals. Artificial ultraviolet light, therefore, might not be an adequate substitute for natural sunlight to maintain vitamin D status of lizards. This possible inadequacy may be because either artificial ultraviolet light has a lower intensity of the wavelengths that induce vitamin D than does sunlight or the intensity of the artificial lighting is not sufficient.
Article
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Fifteen commercially available, complete diets for iguanas, bearded dragons, and chelonians were analysed and compared with the ideal composition of a diet formulated by the authors. The clinical risks of feeding with a too high or a too low content of specific nutrients are described. Nutrient deficiencies are not expected if these diets are the sole source of nutrients. However, one diet had only a marginally adequate protein content, five diets for herbivorous reptiles contained a too low percentage of crude fibre, three diets contained an undesirably high percentage of calcium, and three diets had an extremely high iron content. As a rule, the calcium and iron contents of diets are not declared on the food label, which complicates evaluation of the diets.
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We compared the natural ultraviolet B (UV-B) exposure, dietary vitamin D, and skin-generated vitamin D synthesis for adult males of two species of Jamaican anoles. The more shade-tolerant and thermal-conforming Anolis lineotopus merope, rarely exposed to full sun, experienced less UV-B irradiation in its shady environment than the more heliophilic and thermophilic Anolis sagrei, which frequently basked in full sun during the morning hours (0800-1100 hours). Both species obtained detectable levels of vitamin D(3) in their diet, but the heliophilic A. sagrei obtained more. To compensate for less availability of UV-B and dietary vitamin D, the skin of A. lineotopus merope seems to have acquired a greater sensitivity than that of A. sagrei regarding UV-B-induced vitamin D(3) photobiosynthesis. We assessed this by observing a greater conversion of provitamin D to photoproducts in skin exposed to UV-B from a sunlamp. The reduced skin sensitivity of A. sagrei regarding vitamin D photobiosynthesis may reflect a correlated response associated with less need for vitamin D photobiosynthesis and greater need for UV-B screening capacity as an adaptation to a more damaging UV-B environment. However, the possibility that adaptations for photobiosynthesis of vitamin D and for protection from skin damage could involve independent mechanisms needs investigation. Also, the ability to behaviorally regulate UV-B exposure, as shown for the panther chameleon, would benefit both species of Anolis and should be investigated.
Article
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An automated application of Immunodiagnostic Systems Limited (IDS) OCTEIA 25-hydroxyvitamin D [25(OH)D] enzyme immunoassay was developed for analyses of 25(OH)D in more than 7000 participants of the 1958 cohort. Variation between 25(OH)D assays hampers between-study comparisons and the definition of relevant cutoffs for hypovitaminosis D. The objective of the study was to evaluate the importance of assay variation on the estimated prevalence of hypovitaminosis D and assess the use of statistical harmonization to overcome the observed differences. Agreement analyses were performed between two commercial 25(OH)D assays (IDS enzyme immunoassay and Diasorin RIA), with validation using performance data from Vitamin D External Quality Assessment Scheme (DEQAS). The study was conducted in England, Scotland, and Wales. Members of the 1958 British birth cohort participated in the study. 25(OH)D was measured both by IDS and Diasorin RIA in 781 samples. Additional quality control data were obtained through participation in DEQAS (five distributions throughout the survey). Average 25(OH)D concentrations by IDS were -15.7 and -13.7 nmol/liter lower, compared with Diasorin or DEQAS mean, respectively (both P < 0.0001). Graphical examination demonstrated a dose-related bias between IDS with Diasorin and DEQAS mean, but log transformation removed the bias. After using the log difference between the measurements as an adjustment factor, there were no differences in average 25(OH)D concentrations (P >or= 0.21 for comparison of IDS with Diasorin or DEQAS) and estimates for hypovitaminosis D obtained by IDS were similar to Diasorin. Differences between assays have implications for public health messages about hypovitaminosis D. Harmonization of results with DEQAS enabled the use of previously determined cutoffs for hypovitaminosis D.
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Markers of vitamin D statusVitamin D is hydroxylated in the liver to 25-hydroxyvitamin D (25OHD). This circulates in plasma and serves as a reservoir for further hydroxylation to the biologically active metabolite 1,25-dihydroxyvitamin D. The plasma concentration of 25OHD is the most commonly used biomarker of vitamin D status because it has a long half-life and because it is not under tight homeostatic regulation and therefore reflects vitamin D supply and usage over a period of time(8).In the UK, a threshold concentration of 25 nmol/l (10 ng/ml) has traditionally been used to define a level above which there is little risk of vitamin D-deficiency rickets or osteomalacia(6,7). More recently, links between vitamin D status and other health outcomes (for example, osteoporosis, cancer, CVD, diabetes, tuberculosis) have led to debates about what defines vitamin D sufficiency across the lifecycle and in different population groups(5,9). Proposed lower thresholds of 25OHD concentration range between 50 and 100 nmol/l(5,10). A complication in this debate is the lack of methodological standardisation of 25OHD measurements(11). Participation in the Vitamin D External Quality Assessment Scheme (www.deqas.org) helps to monitor assay and laboratory performance but it is not yet common practice to report these data in publications.PTH has been proposed as a functional marker of vitamin D status because it is linked to 25OHD through the Ca—phosphate homeostatic system. An inverse relationship between the plasma concentrations of PTH and 25OHD has been reported in many cross-sectional and intervention studies(12-15) and an elevated plasma PTH concentration is considered to be a risk factor for osteoporosis(14,15). However, most studies have been conducted among older Caucasian people in Europe and the USA(12-15) and PTH is influenced by many factors other than vitamin D status, including stage of life, ethnic background, dietary Ca and phosphate intake, time of day and assay method(13,16-18). Our studies in The Gambia and China, for example, have shown that plasma PTH concentration is elevated in populations with a low Ca intake, even when vitamin D status is good, and that the inverse correlations between plasma PTH concentration and bone health indices observed in Western countries are not found(5,19,20).In older Caucasian populations bone mineral density (BMD) is a useful marker of fracture risk (www.ISCD.org), and has been used as a functional outcome measure in vitamin D studies. However, the use of BMD measures to predict fracture risk does not necessarily apply to younger people or non-Caucasians(21).Therefore as we have recently argued, it is unlikely that a single biomarker of vitamin D status, threshold value of 25OHD concentration or outcome measure of vitamin D deficiency will be identified for use in all situations, and research is needed to refine existing biomarkers or to establish new indicators(17).
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To determine whether corn snakes exposed to UVB radiation have increased plasma 25-hydroxyvitamin D3 concentrations, compared with control snakes. 12 corn snakes (Elaphe guttata). After an acclimation period in individual enclosures, a blood sample was collected from each snake for assessment of plasma 25-hydroxyvitamin D3 concentration. Six snakes were provided with no supplemental lighting, and 6 snakes were exposed to light from 2 full-spectrum coil bulbs. By use of a radiometer-photometer, the UVA and UVB radiation generated by the bulbs were measured in each light-treated enclosure at 3 positions at the basking surface and at 2.54 cm (1 inch) below each bulb surface; the arithmetic mean values for the 3 positions at the basking surface and each individual bulb surface were calculated immediately after the start of the study and at weekly intervals thereafter. At the end of the study (day 28), another blood sample was collected from each snake to determine plasma 25-hydroxyvitamin D3 concentration. Mean +/- SD plasma concentration of 25-hydroxyvitamin D3 in snakes that were provided with supplemental lighting (196 +/- 16.73 nmol/L) differed significantly from the value in control snakes (57.17 +/- 15.28 nmol/L). Mean exposure to UVA or UVB did not alter during the 4-week study period, although the amount of UVA recorded near the bulb surfaces did change significantly. These findings have provided important insight into the appropriate UV radiation requirements for corn snakes. Further investigation will be needed before exact husbandry requirements can be determined.
Article
We hypothesized the vitamin D-deficient green iguanas with depleted calcium stores would seek to augment calcium intake by self-selection of a high calcium source. Eight green iguanas were offered free-choice ground oystershell in addition to their regular diet. Of these, two had not been exposed to ultraviolet (UV-B) radiation for > 5 years and were demonstrated to be vitamin D-deficient by low circulating levels of the principal vitamin D metabolite, calcidiol (25-hydroxy-cholecalciferol). The six others had been exposed to a UV-B emitting bulb for the previous 3 years and had high circulating calcidiol levels. Average daily food intake (expressed as dry matter per kg body mass) did not differ between the Low-D and High-D iguanas. The daily oystershell intake of the Low-D iguanas (0.02–0.03 g/kg) was lower than that of the High-D iguanas (0.06–0.70 g/kg), leading to a significant difference in calcium intake. The failure of iguanas to increase calcium intake in response to vitamin D-deficiency was puzzling and suggests that vitamin D, as a steroid hormone, may play some role in the expression of calcium appetite. Zoo Biol 16:201–207, 1997. © 1997 Wiley-Liss, Inc.
Book
This outstanding clinical reference provides valuable insights into solving clinical dilemmas, formulating diagnoses, developing therapeutic plans, and verifying drug dosages for both reptiles and amphibians. The information is outlined in an easy-to-use format for quick access that is essential for emergency and clinical situations. Discusses veterinary medicine and surgery for both reptiles and amphibians Features complete biology of snakes, lizards, turtles, and crocodilians Provides step-by-step guidelines for performing special techniques and procedures such as anesthesia, clinical pathology, diagnostic imaging, euthanasia and necropsy, fracture management, soft tissue surgery, and therapeutics Covers specific diseases and conditions such as anorexia, aural abscesses, and digit abnormalities in a separate alphabetically organized section 53 expert authors contribute crucial information to the study of reptiles and offer their unique perspectives on particular areas of study The expansive appendix includes a reptile and amphibian formulary A new full-color format features a wealth of vivid images and features that highlight important concepts and bring key procedures to life 29 new chapters covering diverse topics such as stress in captive reptiles, emergency and critical care, ultrasound, endoscopy, and working with venomous species Many new expert contributors that share valuable knowledge and insights from their experiences in practicing reptile medicine and surgery Unique coverage of cutting-edge imaging techniques, including CT and MRI.
Article
Macronutrient self-selection and responses to dietary protein dilution were investigated in Senegalese sole, a flatfish species of interest for Mediterranean aquaculture. Eight groups of six sole were distributed among 75-l tanks and allowed to feed on three experimental diets composed of pure macronutrients: PC (75% crude protein and 25% carbohydrate), PF (75% crude protein and 25% crude fat) and PFC (10% crude protein, 45% crude fat and 45% carbohydrate). Choosing from the above diets, the sole selected a diet containing 68.0% crude protein, 15.7% crude fat and 16.3% carbohydrate. When the PF diet was diluted 50% with cellulose, the fish increased their feed intake to sustain the energy intake (5.0 kJ/kg BW/day). Their selection of fat remained unchanged, while carbohydrate selection significantly increased by 36% and protein selection slightly decreased by 11%. When both PC and PF were diluted 50% with cellulose, the sole increased their feed intake again to sustain their energy intake (5.2 kJ/kg BW/day). The sole sustained their fat intake, significantly increased their carbohydrate selection by 33%, and significantly decreased their protein selection by 18% compared with the initial situation. These results indicated that Senegalese sole can select from unevenly balanced diets to compose a protein-rich balanced (target) diet, reflecting their carnivorous feeding behaviour. In addition, sole tried to compensate dietary dilutions in order to regulate energy intake by altering their feed intake level and the relative proportions of macronutrients selected.
Article
We hypothesized the vitamin D-deficient green iguanas with depleted calcium stores would seek to augment calcium intake by self-selection of a high calcium source. Eight green iguanas were offered free-choice ground oystershell in addition to their regular diet. Of these, two had not been exposed to ultraviolet (UV-B) radiation for > 5 years and were demonstrated to be vitamin D-deficient by low circulating levels of the principal vitamin D metabolite, calcidiol (25-hydroxy-cholecalciferol). The six others had been exposed to a UV-B emitting bulb for the previous 3 years and had high circulating calcidiol levels. Average daily food intake (expressed as dry matter per kg body mass) did not differ between the Low-D and High-D iguanas. The daily oystershell intake of the Low-D iguanas (0.02–0.03 g/kg) was lower than that of the High-D iguanas (0.06–0.70 g/kg), leading to a significant difference in calcium intake. The failure of iguanas to increase calcium intake in response to vitamin D-deficiency was puzzling and suggests that vitamin D, as a steroid hormone, may play some role in the expression of calcium appetite. Zoo Biol 16:201–207, 1997. © 1997 Wiley-Liss, Inc.
Article
To assess the importance of diet and light for indoor maintenance, hatchling panther chameleons were reared for 1 year on crickets fed diets that differed in vitamin concentrations and in different light environments. Dietary transfer of vitamins from the cricket diet to the lizards via the crickets was quantified, as was UV irradiance. There was a statistically significant dietary enhancement of growth by both vitamins on males. UV-A irradiation significantly suppressed growth of females. Low vitamin A shortened life span and resulted in a number of gross and histological pathologies. Hepatocellular lipidosis, indicating a possible toxicosis, occurred with all diets and light treatments. Higher vitamin A resulted in mild soft-tissue mineralization, and high vitamin D shortened the life span of females. Low vitamin A drastically reduced reproduction in both sexes. The intermediate levels of dietary vitamins resulted in the best production of viable eggs by females. However, without high UV-B irradiation, all viable eggs died at term and contained different vitamin levels than hatching eggs from wild-caught females. Baseline levels of egg calcium are given for hatching eggs from wild-caught females. Modifications in current husbandry procedures are recommended. © 1996 Wiley-Liss, Inc.
Article
Having previously documented experimentally the need for ultraviolet B (UVB) irradiation (290–315 nm) in the light environment of captive female panther chameleons (Furcifer pardalis) to ensure hatching success of their eggs, we investigated optimal UVB irradiation levels. From 1996–1998 28 hatchling female panther chameleons were raised to maturity and bred (using vitamin and mineral-fortified insect diets low in vitamin D) in nine different artificial UVB light environments. Seven of the environments included long (12 hr/day) low irradia-tion exposures ranging from 1.7 to 22 μW/cm2 UVB, with a corresponding conversion of provitamin D3 to photoproducts in in vitro models of 0.18 to 1.52% in 2 hr. Two environments included short (0.5 and 1.0 hr/day), high irradiation exposures of 55 and 49 μW/cm2 UVB, respectively, with a corres-ponding conversion of provitamin D3 to photoproducts in in vitro models of 8.3% to 14.6% in the respective 0.5- and 1.0-hr time periods. Females raised with the mid-level long/low exposures (5–15 μW/cm2 UVB; 0.52–1.32% conversion to photoproducts in in vitro models) produced viable eggs with a significantly higher percentage of hatching compared to those with the extreme (highest or lowest) long/low exposures. Those raised with the short-/high-exposure environments produced viable eggs with a generally high percentage of hatching, but success was variable. The results and techniques for light quality assessment are interpreted, with recommendations for practical application by the herpetoculturist desiring to successfully breed panther chameleons in captivity. Zoo Biol 21:525–537, 2002. © 2002 Wiley-Liss, Inc.
Article
Chicken from two broiler strains known to differ in growth rate and feed conversion (Growth) and in high breast meat yield (Yield) were grown to 10 days of age on a common starter diet and from 11-49 days were provided single diets (control) or isoenergetic choices between 15% and 24% or 15% and 32% crude protein (CP) diets. The Growth strain had greater body weight and intake of feed, protein and energy at all intervals except for 42-49 d of age as well as carcass characteristic in weight basis than did Yield strain. However, the latter strain had better feed, protein and energy conversion at 42-49 d of age and breast meat yield than did the former strain. Birds fed the isoenergetic diets varying in protein content had similar body weight, feed intake, feed conversion, energy intake, energy conversion and carcass characteristic expressed in relative term as did birds fed the control diets. Only for the last period of feeding (42-49 d of age), the protein consumption and conversion by birds fed choice of 15 and 24% CP were higher than those of birds fed the control diets. The Growth strain had a slightly greater preference for the high protein diet and consequently a higher protein intake compared to Yield strain. It seems that the selection of protein density was determined by the growth rate rather than the breast yield. There was a marked preference for the low protein diet (15% CP) over the high protein diets (24 and 32% CP), but this preference was reduced when the low protein diet was offered with the 24% CP diet. The levels of selected protein of birds given the choice diets were higher than those of control diets except for the period of 10-22 d of age and increased with age. These data indicate that these choice feeding systems can detect differences in protein requirement of two strains influenced by the growth rate.
Article
To evaluate vitamin D concentrations in juvenile llamas and alpacas with hypophosphatemic rickets. Prospective cohort study. 21 llamas (14 with rickets, 7 clinically normal) and 9 alpacas (6 with rickets, 3 clinically normal). Blood samples were collected at the time of diagnosis and prior to the initiation of treatment. Serum concentrations of calcium, inorganic phosphorus, and 25-hydroxycholecalciferol (vitamin D3) were determined on all samples. Comparisons were completed for disease status, age, sex, species, month of birth, and all interactions. Serum concentrations of phosphorus and vitamin D were lower in affected llamas and alpacas than in clinically normal llamas and alpacas, even when mean concentrations were adjusted for age differences. Species (llama or alpaca), sex, and age did not affect any of the metabolite concentrations within this study population. Month of birth influenced vitamin D concentrations and number of affected llamas and alpacas per month. The greatest number of affected llamas and alpacas was identified between January through March, suggesting a seasonal pattern to this syndrome. Treatment of affected llamas and alpacas with vitamin D resulted in increased concentrations of phosphorus and vitamin D. Serum phosphorus concentration was best predicted by 2 independent variables (serum vitamin D concentration and month of birth). We believe vitamin D deficiency is the primary cause of hypophosphatemic-rickets of growing camelids, and the observed hypophosphatemia is secondary to a primary deficiency of vitamin D. Appropriate treatment with vitamin D supplements can correct hypophosphatemia and vitamin D deficiency in camelids.
Article
The 1alpha-hydroxylated metabolite of 25-hydroxyvitamin D(3), 1,25-dihydroxyvitamin D(3), is the biologically most active metabolite of vitamin D. The 24-hydroxylated metabolites were generally considered as degradation products of a catabolic pathway finally leading to excretion of calcitroic acid. Studies with analogues fluorinated at the C-24 position did not indicate a physiological function for 24R,25(OH)(2)D(3). Nevertheless throughout the years various studies showed biologic effects of other metabolites than 1alpha,25(OH)(2)D(3). In particular the metabolite 24R,25(OH)(2)D(3) has been functionally analyzed, e.g. with respect to a role in normal chicken egg hatchability and effects on chondrocytes in the resting zone of cartilage. Numerous studies have shown the presence of the vitamin D receptor in bone cells and effects of 1alpha,25(OH)(2)D(3) on bone and bone cells. Also for 24R,25(OH)(2)D(3) studies have been performed focusing on effects on bone and bone cells. The purpose of this review is to summarize the data regarding 24R,25(OH)(2)D(3) and bone and to evaluate its role in bone biology.
Article
Several disease syndromes in captive rhinoceroses have been linked to low vitamin status. Blood samples from captive and free-ranging black (Diceros bicornis) and white rhinoceros (Ceratotherium simum) and tissue samples of captive individuals from four rhinoceros species were analysed for vitamins A and E. Circulating vitamin A levels measured as retinol for free-ranging versus captive black and white rhinoceros were 0.04 (+/- 0.03 SD) vs. 0.08 (+/- 0.08) and 0.07 (+/- 0.04) vs. 0.06 (+/- 0.02) microgram/ml, respectively. Circulating vitamin E levels measured as alpha-tocopherol were 0.58 (+/- 0.30) vs. 0.84 (+/- 0.96) and 0.62 (+/- 0.48) vs. 0.77 (+/- 0.32) microgram/ml, respectively. In contrast to earlier findings, there was no significant difference in vitamin E concentration between captive and free-ranging black rhinoceros. When the samples of captive black rhinoceros were grouped into those taken before 1990 and after 1990, however, those collected before 1990 had significantly lower (P < 0.001) vitamin E levels (0.46 +/- 0.83 microgram/ml) and those collected in 1990 or later significantly higher (P < 0.001) vitamin E levels (1.03 +/- 1.04 micrograms/ml) than the captive population as a whole. This is probably due to increased dietary supplementation. There were significant differences in circulating vitamin concentrations in black rhinoceroses from different regions in the wild. Serum 25-hydroxy (OH) vitamin D3 averaged 55.7 ng/ml in free-ranging rhinoceroses; no carotenoids were detected in any blood samples. Captive black and white rhinoceroses appear to be adequately supplemented in vitamin A and E. Captive Indian rhinoceroses (Rhinoceros unicornis) had significantly lower vitamin A concentrations in blood (P < 0.001) and higher vitamin A concentrations in liver tissue samples (P < 0.001) than other rhinoceros species. Equine requirements are not recommended as a model for rhinoceros vitamin requirements.
Article
Vitamin D is one of the oldest hormones that have been made in the earliest life forms for over 750 million years. Phytoplankton, zooplankton, and most plants and animals that are exposed to sunlight have the capacity to make vitamin D. Vitamin D is critically important for the development, growth, and maintenance of a healthy skeleton from birth until death. The major function of vitamin D is to maintain calcium homeostasis. It accomplishes this by increasing the efficiency of the intestine to absorb dietary calcium. When there is inadequate calcium in the diet to satisfy the body's calcium requirement, vitamin D communicates to the osteoblasts that signal osteoclast precursors to mature and dissolve the calcium stored in the bone. Vitamin D is metabolized in the liver and then in the kidney to 1,25-dihydroxyvitamin D [1,25(OH)(2)D]. 1,25(OH)(2)D receptors (VDR) are present not only in the intestine and bone, but in a wide variety of other tissues, including the brain, heart, stomach, pancreas, activated T and B lymphocytes, skin, gonads, etc. 1,25(OH)(2)D is one of the most potent substances to inhibit proliferation of both normal and hyperproliferative cells and induce them to mature. It is also recognized that a wide variety of tissues, including colon, prostate, breast, and skin have the enzymatic machinery to produce 1,25(OH)(2)D. 1,25(OH)(2)D and its analogs have been developed for treating the hyperproliferative disease psoriasis. Vitamin D deficiency is a major unrecognized health problem. Not only does it cause rickets in children, osteomalacia and osteoporosis in adults, but may have long lasting effects. Chronic vitamin D deficiency may have serious adverse consequences, including increased risk of hypertension, multiple sclerosis, cancers of the colon, prostate, breast, and ovary, and type 1 diabetes. There needs to be a better appreciation of the importance of vitamin D for overall health and well being.
Article
Calcium-deprived rats have elevated intakes of CaCl2, other calcium salts, and some non-calcium compounds. We used taste reactivity to examine the effects of calcium deprivation on the palatability of CaCl2 and other solutions. Nine male Sprague-Dawley rats were calcium-deprived by maintenance on a low-calcium diet, and eight replete rats were used as controls. All rats were videotaped during intraoral infusion of the following solutions: 30 and 300 mM CaCl2, 30 mM calcium lactate, 100 and 600 mM NaCl, 30 mM MgCl2, 1 mM quinine.HCl, 2.5 mM sodium saccharin, and deionized water. We counted individual orofacial and somatic movements elicited by the infusions and used them to calculate total ingestive and aversive scores. Relative to controls, calcium-deprived rats gave a significantly larger number of tongue protrusions and had higher total ingestive scores for CaCl2, calcium lactate, NaCl, and MgCl2. Our results suggest that CaCl2, calcium lactate, NaCl, and MgCl2 taste more palatable to rats when they are calcium-deprived than replete, and this may be responsible for the increased intake of these solutions following calcium deprivation.
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