No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
The effect of threonine and vitamin A on immune system in broiler chickens
Abstract
Two independent experiments were conducted with Ross broilers to determine the incremental levels of threonine and vitamin A on immune system. In first experiment one-day-old Ross broilers were randomly assigned to 16 pens with 10 chicks per pen in a completely randomized design. The dietary treatments consisted of an isonitrogenous corn-soybean meal-based diet with the addition of graded levels of L-threonine supplementation. Dietary treatments contained 0.8% (NRC requirement), 0.87% (average of NRC and Ross requirement), 0.94% (Ross requirement) and 1.01% (more than Ross requirement) total threonine. In second experiment, one hundred sixty day-old male broiler chicks (Ross 308) were randomly assigned to 16 pens measuring. All birds fed wheat-soybean meal based diets. The diets were formulated to either meet or exceed the recommended NRC (1994) nutrient requirements for broilers. Experimental diets were as follows: basal diet without vitamin A; basal diet plus 1500 IU/Kg vitamin A (NRC 1994 requirement); basal diet plus 6250 IU/Kg vitamin A (between Ross 2007 and NRC 1994 requirement); basal diet plus 11000 IU/Kg vitamin A (Ross 2007 requirement). Fourteen days after feeding the treatments, cutaneous basophil hypersensitivity (CBH), cell-mediated immune response, was determined as the increase in toe-web skin thickness after an injection with phytohemagglutinin-P and twenty-two days after feeding the diets, heterophils and lymphocytes were enumerated. Humoral immunity was assessed by intravenous injection of 7% sheep red blood cell (SRBC) at 22 days of age. In first experiment, the titers of IgG, IgM and IgA for primary and secondary responses were numerically, but not significantly, increased in birds fed diet containing 0.87% threonine and decreased in 0.94% and 1.01% threonine. Cutaneous basophil hypersensitivity was not affected in chicks, whereas there was a tendency for an increase in birds fed a diet containing 0.87% threonine at 24 h after injection. In second experiment, the titers of IgG, IgM and IgA for primary and secondary responses were significantly increased in birds fed diet containing vitamin A. cutaneous basophil hypersensitivity was also increased by addition vitamin A in the diet. The results obtained on the present study indicated that threonine and Vitamin A requirements of broiler based on recommendation of NRC are not sufficient to meet the requirement of the new commercial poultry and commercial broiler companies under non-hygienic condition.
... These findings are supported by Corzo et al. (2007), who reported a similar increase in heterophil and lymphocyte percentages with higher dietary levels of Thr while observing no effect on the H/L ratio in Ross × Ross male chicks. Additionally, Moghaddam and Emadi (2014) noted a non-significant impact on lymphocytes, heterophile%, and the H/L ratio with higher dietary Thr levels. Similarly, Mahmoud, Ibrahim, and Badawi (2013) concluded that the higher inclusion of olive oil led to Effect of various dietary threonine and oil levels on broiler chickens' goblet cell number of jejunum. ...
Background
The inclusion of synthetic amino acids in poultry nutrition plays a crucial role in both enhancing the synthesis of immunoglobulins and elevating the overall comprehensiveness of the amino acid profile.
Objectives
This research examined the effects of consuming threonine (Thr) in various forms levels with low or high oil on broiler chickens' growth and immunity.
Methods
We investigate the growth performance, feed efficiency, immune response, intestinal morphology, absorptive capacity, and expression of some genes related to the feed intake (Pro‐opiomelanocortin [POMC]), fatty acid synthesis (Acetyl‐CoA Carboxylase [ACC]), immunity (lipopolysaccharide‐induced tumour necrosis like alpha factor [LITAF]), and heat shock protein 70 (HSP70). Eight groups of chicks were used, including four dietary Thr levels (100%, 115%, 130%, or 145%) with two oil levels (mixture of sunflower 50% and soybean oils 50%): (control) and high.
Results
The higher dietary Thr level (145%) with high oil inclusion significantly increased ACC and POMC gene expression, resulting in the lowest feed intake, body weight gain (BWG), and liver fat content. Combining high oil with 115% Thr was the optimum for the broilers. The birds have significant (p ≤ .05) growth performance, immune parameters, and intestinal health, as well as the lowest expression of ACC, POMC, HSP70, and LITAF, which was reflected in better feed conversion ratio and lower incidence of fatty liver, thermo‐resistance, and immune status of the birds.
Conclusions
The combination of high oil and 115% Thr levels optimises broiler health and productivity, enhancing growth, immune function, and gut health. This diet lowers the expression of genes associated with fatty liver and stress, leading to better feed efficiency, thermo‐resistance, and overall well‐being. Adopting these dietary adjustments can improve broiler performance and economic viability in poultry farming by enhancing essential productivity metrics.
... Sepehri Moghaddam and Emadi (2014) aimed to assess the effect of vitamin A on the immune system of broilers. The experiment included four diets with varying levels of vitamin A (0, 1500, 6250 and 11000 IU/kg feed), and the immunological response was evaluated using several measures such as immunoglobulin titers, cutaneous basophil hypersensitivity, and heterophils and lymphocytes counts. ...
Vitamin A (retinol) is an essential micronutrient with a crucial role in the immune system of non-ruminant animals, such as swine and poultry. It includes three chemical compounds with distinct properties and functions in the body: retinol, retinal, and retinoic acid. In monogastric feed, vitamin A is primarily present in the form of retinyl esters. The metabolism of dietary vitamin A esters involves their conversion to retinol, which is then transported to different tissues and cells for further metabolism into active forms such as retinoic acid. These active forms of vitamin A have been found to play a crucial role in regulating both innate and adaptive immune responses. Specifically, they are involved in the differentiation, proliferation, and function of immune cells such as T and B lymphocytes, as well as dendritic cells. Vitamin A deficiency can lead to impaired cellular immunity, reduced antibody production, and consequently an increased susceptibility to infections. In swine and poultry, hypovitaminosis A can also affect gut-associated lymphoid tissues, leading to gut-related health problems and compromised growth performance. On the other hand, vitamin A supplementation has been shown to have immunomodulatory effects on non-ruminant immune responses. By administering or supplementing retinol, immune cell proliferation, antibody production, and cytokine secretion can be enhanced, which can ultimately result in improved immune function and disease resistance. Therefore, vitamin A has potential applications as an immuno-micronutrient for improving health and preventing diseases in swine and poultry. However, the optimal dosage and timing of vitamin A supplementation need to be carefully determined based on the specific requirements of different non-ruminant species and their production stages. Overall, a better understanding of the role of vitamin A in non-ruminant nutritional immunology could have significant implications for animal health and productivity and could inform the development of effective dietary strategies to optimize immune function and prevent diseases in swine and domestic fowl. This review paper aims to offer valuable insights into the role of vitamin A in the nutritional immunology of non-ruminants while also emphasizing the current gaps in knowledge and potential areas for further research.
... Nutraceuticals have been in focus in poultry science quite recently due to the nutritional and healthier properties of feed ingredients and the adverse effects of chemical pharmaceuticals like antibiotic resistance and drug residues (Elnesr et al. , 2020. Amino acids (Ghoreyshi et al. 2019), minerals (Khatun et al. 2019), and vitamins (Ahmad et al. 2019) which are common ingredients of poultry ration or a combination of them (Moghaddam and Emadi 2014;Horvath and Babinsky 2018) can be nutraceuticals, especially important in poultry feeding. Generally, poultry receives nutrients through the consumption of natural feedstuffs, but some key essential amino acids (lysine, methionine, threonine and tryptophan), vitamins and minerals are often offered as synthetic supplements (Ravindran 2010). ...
Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals’ normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.
... However, as far as L-carnitine was concerned, Deng et al. [65] found that the dietary addition of 0 (control), 100 mg/kg, or 1000 mg/kg of L-carnitine did not affect primary antibody responses to SRBC at the 4th week but that birds fed on a diet with 1000 mg of L-carnitine had a higher primary antibody response against SRBC than broilers in other groups at the 12th week. Moghaddam and Emadi [66] reported that there was a tendency for an increase in IgG, IgM, and IgA antibody titers as dietary threonine increased from 0.8% to 0.87%. However, IgG, IgM, and IgA antibody titers decreased when threonine was administrated at levels of 0.94% and 1.01%. ...
L-carnitine as well as lysine and methionine are amino acids of important nutritional and nutraceutical interest and are used in nutritional strategies as dietary supplements to improve feed quality characteristics in animals and broiler chicken in particular. This study investigated the effect of different levels of L-carnitine and extra levels of lysine-methionine on growth performance, carcass characteristics, and some immune system markers. Two hundred seventy male Ross 308 broilers were a fed control diet (C) and eight different diets supplemented with an excess of amino acids. In the experimental diets, identified as D1, D2, D3, D4, D5, D6, D7, and D8, extra L-carnitine, lysine, and methionine were added in excess with respect to the American National Research Council (NRC) recommendations: L-carnitine equal to NRC (D1), control diet supplemented with lysine at 30% in excess of NRC, methionine at 30% in excess of NRC, and L-carnitine equal to NRC (D2), control diet supplemented with lysine equal to NRC, methionine equal to NRC, and L-carnitine at 15% in excess of NRC (D3), control diet supplemented control diet supplemented with lysine at 15% in excess of NRC, methionine at 15% in excess of NRC, and L-carnitine at 15% in excess of NRC (D4), control diet supplemented lysine at 30% in excess of NRC, methionine at 30% in excess of NRC, and L-carnitine at 15% in excess of NRC (D5), control diet supplemented with lysine equal to NRC recommendations, methionine equal to NRC recommendations, and L-carnitine at 75% in excess of NRC (D6), control diet supplemented with lysine at 15% in excess of NRC, methionine at 15% in excess of NRC, and L-carnitine at 75% in excess of NRC (D7); and control diet supplemented with lysine at 30% in excess of NRC, methionine at 30% in excess of NRC, and L-carnitine at 75% in excess of NRC (D8). During the starter and growth phases, feed intake was not affected by dietary treatment (p > 0.05). By contrast, body weight and FCR were both affected (p < 0.01) during the starter period. During the finisher phase, feed consumption was affected (p < 0.05) by dietary treatment. Feed intake of broilers fed on C, D3, D6, and D7 were statistically similar (p > 0.05) (1851.90, 1862.00, 1945.10, and 1872.80 g/pen/day, respectively) and were higher (p < 0.05) than 1564.40 g/pen/day (D5). With the exception of drumsticks, neck, back thoracic vertebrae, and proventriculus weights, the economical carcass segments were not affected (p > 0.05) by the dietary supplementation of amino acids. Duodenum and ileum weights and lengths decreased with amino acid supplementation (p < 0.05). IgT and IgG titers against Sheep Red Blood Cells (SRBC) for both primary and secondary responses were not affected by dietary treatments (p > 0.05). Dietary amino acids supplementation did not affect IgM titer after the secondary challenge (p > 0.05) and had a significant effect (p < 0.05) on serum antibody titers in broilers vaccinated against Newcastle disease (NCD) and Gumboro ‘s disease at the 27th and 30th days, respectively.
... However, as far as L-carnitine was concerned, Deng et al. [65] found that the dietary addition of 0 (control), 100 mg/kg, or 1000 mg/kg of L-carnitine did not affect primary antibody responses to SRBC at the 4 th week but that birds fed on a diet with 1000 mg of L-carnitine had a higher primary antibody response against SRBC than broilers in other groups at the 12 th week. Moghaddam and Emadi [66] reported that there was a tendency for an increase in IgG, IgM, and IgA antibody titers as dietary threonine increased from 0.8% to 0.87%. However, IgG, IgM, and IgA antibody titers decreased when threonine was administrated at levels of 0.94% and 1.01%. ...
L-carnitine as well as lysine and methionine are amino acids of important nutritional and nutraceutical interest and are used in nutritional strategies as diet supplements to improve feed quality characteristics in animals and broiler chicken in particular. This study investigated the effect of different levels of L-carnitine and extra levels of lysine-methionine on growth performance, carcass characteristics, and some immune system markers. Two hundred seventy male Ross 308 broilers were a fed control diet (C) and eight different diets supplemented with an excess of amino acids. In the experimental diets, identified as D1, D2, D3, D4, D5, D6, D7, and D8, extra L-carnitine, lysine, and methionine were added in excess with respect to the American National Research Council (NRC) recommendations: L-carnitine equal to NRC (D1); control diet supplemented with lysine at 30% in excess of NRC, methionine at 30% in excess of NRC, and L-carnitine equal to NRC (D2); control diet supplemented with lysine equal to NRC, methionine equal to NRC, and L-carnitine at 15% in excess of NRC (D3); control diet supplemented control diet supplemented with lysine at 15% in excess of NRC, methionine at 15% in excess of NRC, and L-carnitine at 15% in excess of NRC (D4); control diet supplemented lysine at 30% in excess of NRC, methionine at 30% in excess of NRC, and L-carnitine at 15% in excess of NRC (D5); control diet supplemented with lysine equal to NRC recommendations, methionine equal to NRC recommendations, and L-carnitine at 75% in excess of NRC (D6); control diet supplemented with lysine at 15% in excess of NRC, methionine at 15% in excess of NRC, and L-carnitine at 75% in excess of NRC (D7); and control diet supplemented with lysine at 30% in excess of NRC, methionine at 30% in excess of NRC, and L-carnitine at 75% in excess of NRC (D8). During the starter and growth phases, feed intake was not affected by dietary treatment (p > 0.05). By contrast, body weight and FCR were both affected (p < 0.001) during the starter period. During the finisher phase, feed consumption was affected (p < 0.05) by dietary treatment. Feed intake of broilers fed on C, D3, D6, and D7 were statistically similar (p > 0.05) (1851.90, 1862.00, 1945.10, and 1872.80 g/pen/day, respectively) and were higher (p < 0.05) than 1564.40 g/pen/day (D5). With the exception of drumsticks, neck, back thoracic vertebrae, and proventriculus weights, economical carcass segments were not affected (p > 0.05) by the dietary supplementation of amino acids. Duodenum and ileum weights and lengths decreased with amino acid supplementation (p < 0.05). IgT and IgG titers against Sheep Red Blood Cells (SRBC) for both primary and secondary responses were not affected by dietary treatments (p > 0.05). Dietary amino acids supplementation did not affect IgM titer after the secondary challenge (p > 0.05) and had a significant effect (p < 0.05) on serum antibody titers in broilers vaccinated against Newcastle disease (NCD) and Gumboro ‘s disease at the 27th and 30th days, respectively.
... The PABM diet increased the WBC of the birds in the current study. This is similar to earlier report that supplementation of vitamin A increases WBC concentration in chickens (Akbari et al., 2008).Other reports also indicate that vitamin A and carotenoids increase the immune response in chickens and also reduce common avian infections such as coccidiosis and lesions that cause significant losses to poultry farmers (Díaz-Gómez et al., 2015;Sepehri Moghaddam & Emadi, 2014). Carotenoids have been documented to have antioxidant activities that reduces stress and help the birds to fight infections better (Nogareda et al., 2016). ...
The current study was conducted to investigate the influence of provitamin A biofortified maize (PABM) diet, sex and age of birds on the haematological and serum biochemistry parameters of indigenous chickens. A total of ninety-six 13 week old male and female Ovambo chickens were reared and fed on either white maize (WM) a low vitamin A diet or a PABM based diet for eight weeks. Each diet was replicated four times. Packed cell volume (PCV), haemoglobin (Hb), erythrocyte concentration (RBC), leucocytes concentration (WBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were measured. Albumin (ALB), globulin (GLOB), total proteins (TP), triglycerides (TRI), cholesterol (CHOLES), uric acid (UA) and creatinine (CREAT) concentrations were assessed. The activity of alanine transaminase (ALT) alkaline phosphate (ALP) and aspartate transaminanse (AST) were also assayed. The PABM diet increased (p<0.05) PCV and WBC of female birds. All mean values for the haematological parameters regardless of the age, sex and diets were within the normal range. Age had an effect (p<0.05) on ALT, TP, GLOB, TRI and UA. Sex of the birds significantly influenced the TP, GLOB, ALB, CREAT and TRI levels. There was significant interaction of diet and age of bird on ALP, ALT, and GLOB concentrations. The cholesterol level in 18 weeks old male birds fed on the WM diet was above the normal range. In conclusion, feeding PABM diet to female and male indigenous chickens will not negatively impact on the health status of indigenous chickens.
... Thr supplementation at 30% more than recommended requirement improved RBCs, Hb% and PCV% compared with other treatments. These results are in agreement with Moghaddam and Emadi (2014) who reported that the higher dietary Thr levels (0.87 and 0.94%) increased Hb content than control group (0.80%). ...
A total of 320 one-day-old Cobb chicks of mixed sex were used to investigate the impact of some amino acids supplementation and coccidial infection of broiler chicken on the growth performance, Immune response, some blood serum biochemical changes and intestinal morphology of broiler chickens. The chicks were randomly allotted into 10 equal groups, the first group were fed on the basal diet contain requirement of lysine (Ly), methionine (Met) and threonine (Thr) according to recommended catalog of the Cobb breed. Group 2 – 4 fed on the basal diet with 30% extra Ly, Met or Thr than recommended requirement respectively. Group 5 fed on the basal diet with extra combination of Ly, Met and Thr. Groups 6 – 10 fed on the same design as described for groups 1 – 5 with coccidial infection. It was found that the excess Ly, Met or Thr non-significantly increased the final body weight and significantly (P≤0.05) improved the feed efficiency and the performance index. Our data revealed that extra amino acids supplementation improved the blood picture and enhanced the immune response via increase the WBCs count and antibodies titer and significantly (P≤0.05) decreased blood serum carotenoids at 20th days of broiler age also reduced the coccidial fecal oocyst output at 14th or 28th days post-infection. It can be concluded that using of 30% extra methionine supplementation during the early age of broiler chickens and using 30% extra lysine supplementation during the grower and finisher period improved the performance and ameliorated the severity of coccidiosis.
... Serum immunoglobulin levels are routinely determined in clinical practice to check the Humoral immune status (Gonzalez-Quintela et al., 2008). Serum immunoglobulin concentration increased on 3 rd and 5 th week after AV/CSP/29 premix supplementation to Group T1, might be because of its constituent Vitamin A. Researchers showed that after Vitamin A supplementation significant increase in Immunoglobulin (Moghaddam and Emadi, 2014). High carcass yield, dressing percentage and improved tibial mineralization was observed in AV/CSP/29 premix supplemented Group T1. ...
Objective: Efficacy of AV/CSP/29 premix (Ca, P supplement with Vit. A and D3 along with synergistic herbs) (M/S Ayurvet Ltd.) was evaluated in commercial broiler chicks.
Materials and methods: A total of 144 day-old chicks were randomly divided into three groups. Group T0 (n=48) control group, supplemented with basal diet without any additional source of calcium (Ca) and phosphorus (P). Group T1 (n=48) was administered with AV/CSP/29 premix at 500 gm/ton of feed and Group T2 birds (n=48) were supplemented with Brand A at 500 gm/ton of feed for 0 to 42 days. Parameters viz., growth, performance, serum biochemical and carcass quality traits were evaluated.
Results: More gain in body weight was observed in the AV/CSP/29 premix supplemented group (T1) birds as compared to other groups. Similarly, FCR was improved in the AV/CSP/29 premix supplemented group (T1) birds. Blood Ca and P concentrations were comparatively improved in AV/CSP/29 premix supplemented birds. Parameters viz., carcass yield, dressing percentage, tibial mineralization, water holding capacity and extract release volume were also found to be better in AV/CSP/29 premix supplemented group (T1) birds.
Conclusion: The results from the current study suggest that feeding of AV/CSP/29 premix to broiler chickens may have a beneficial effect on bone quality and in improving overall performance. [J Adv Vet Anim Res 2016; 3(3.000): 268-273]
Vitamin A, a critical micronutrient, plays a vital role in maintaining poultry health and maximizing productivity. This comprehensive review paper conducts a thorough analysis of the consequences of vitamin A deficiency in domestic fowl. It delves into the physiological functions of vitamin A and investigates how hypovitaminosis A impacts growth, immune function, reproduction, and overall poultry performance. Additionally, the review explores effective strategies for preventing and managing vitamin A deficiency, such as dietary adjustments and supplementation, while addressing the specific requirements for vitamin A intake. The implementation of these strategies holds immense importance in optimizing poultry management practices and achieving peak performance in poultry production. A profound understanding of the prevalence and factors contributing to clinical and subclinical vitamin A deficiency in domestic fowl is essential for ensuring the efficiency of poultry farming operations. Recognizing the pivotal role of vitamin A and applying the appropriate measures empowers poultry farmers to enhance the health outcomes and overall performance of their flocks.
Since the banning of antibiotics in animal feeds (2006), there has been an increase in the number of studies looking for alternatives to stimulate the gut immune system. The main objective of our review article is to underline the nutraceutical properties of Curcuma longa and Spirulina platensis in the broiler chicken industry, and the experimental data were obtained by analyzing literature sources. Spirulina platensis is widely recognized as a valuable protein source, containing approximately 55-70% protein, 25% carbohydrates, essential amino acids, and 18% fatty acids. It is also rich in various vitamins like thiamin, riboflavin, pyridoxine, vitamin B12, vitamin C, gamma-linolenic acid, phycocyanins, tocopherols, chlorophyll, beta-carotenes, carotenoids, exhibiting positive effects on growth performance, gut integrity, and immunity. The anti-inflammatory effect of spirulina supplementation at different levels showed a decrease in caspase-3 and the TNF-α immunolabeling index; a reduction in IL-1β, IL-2 and IFN-γ; and an increase in the expression of the anti-inflammatory cytokine IL-4. Spirulina inhibits the synthesis of cytokines IL-1, IL-6, and TNF-gamma in addition to the activities of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) enzymes. Turmeric also positively influences the growth, egg production, and overall health of chickens. Cur-cumin, the most potent component of turmeric, possesses additional pharmacological activities, including hepatoprotective, immunostimulant, and anticancer effects. Its immunomodulatory properties greatly enhance the immune system response, acting as a natural antibiotic against pathogens and decreasing levels of proinflammatory interleukins IL-1β, IL-6, IL-2, IL-18, and TNF-α.
Broiler is any chicken (Gallus gallus domesticus) that is bred and raised specifically for meat production. Comparatively, they are
characterised by fast growth rates, high feed conversion ratio and low levels of activity. They reach slaughter weights between 4 to 7
weeks. Commercial broilers are subjected to very strenuous conditions before slaughter which includes , overcrowding in crates dur�ing transportation, deprivation of feed and water. Haematology helps in examination of cellular and fluid protein of blood. However,
the serum is the component that is neither a blood cell nor a clotting factor but a part of blood like water that contains substances
called antibodies that fight disease. This study seeks to ascertain the health and physiological status of these birds at the time of
slaughter by analysing their blood and serum biochemistry. Fifty commercial broiler chickens were randomly selected at the Bukuru
live bird market of Jos south Local Government Area in Plateau State, Nigeria. The haematological parameters of the chickens were
PCV 27-42%,RBC 2.2-4.0 × 106 µl, WBC 1.0-9.5 × 103µl L 20.50 and all the values were within normal range. Similarly, all the serum
biochemical values in this study were wthin normal range for broiler chickens. This signifies that the broilers slaughtered in the study
area are apparently healthy and fit for consumption. We recommend humane handling of these birds and improved sanitary condi�tions at the slaughter premises.
Keywords: Broiler; Haematology; Serum-Biochemistry; Jos; Nigeria
One to 42-d-old (432) female broilers were fed different levels of inorganic selenium (ISe) and organic selenium (OSe), according to the following treatments: (1) 0.3 mg ISe; (2) 0.3 mg ISe + 0.2 mg OSe; (3) 0.5 mg ISe and (4) 0.3 mg OSe/ kg of feed. All birds were vaccinated against infectious bursal disease (IBD) at 19d of age and three birds/replicate (R) were inoculated with sheep red blood cells (SRBC) at 32d. Three other birds/R received Freund's adjuvant at 37d and avian tuberculin (AT) in the wattle at 47d of age. All birds were submitted to heat stress after 21d. Performance parameters, bursa and spleen weights, lymphocyte bursa depletion, antibody (Ab) production against IBD and SRBC, hematocrit, leukocytes, heterophil/lymphocyte ratio (H/L), and cellular reaction to AT were evaluated. The contrast analysis showed that OSe has improved feed intake (FI) between day 1 and 42 (p<0.10). Birds fed ISe presented worse H/L ratio (p<0.10), but higher Ab titers against IBD (p<0.04) and SRBC (p<0.05) than birds fed OSe, but OSe supplemented birds showed lower lymphocyte depletion scores in the bursa. The higher FI promoted by OSe may be beneficial when rearing broilers in hot weather. The use of ISe induced higher humoral immune response.
Betaine, a donor of labile methyl groups, can spare choline and methionine but cannot replace these compounds in poultry diets. Betaine is synthesized from choline by choline oxidase and it can donate methyl groups to homocysteine to form methionine. Physiologically, betaine is one of several compounds used by cells to regulate osmotic pressure. Among the potential benefits of its inclusion in poultry feeds are sparing choline, carcass fat reduction and aiding cell osmoregulation. Some feed ingredients are natural sources of betaine per se. This review considers the metabolism, functions and applications of betaine in poultry.
Feedstuffs and additives with immunomodulatory characteristics were investigated to reduce losses caused by disease and to optimize the production potential of the bird. Therefore, the objective of this study was to assess the influence of yeast extract and prebiotics on broilers fed a prestarter diet, and the impact of ambient temperature on maternal and postvaccinal humoral immune responses. The birds were fed diets supplemented with yeast extract, prebiotics, or both in the prestarter phase (1 to 7 d), and from d 8 on, all birds received the same diet. The birds were vaccinated against Newcastle disease virus and infectious bursal disease at 8 and 18 d of age. The addition of yeast extract and prebiotic in the prestarter phase did not change the humoral immune response against Newcastle disease virus or infectious bursal disease throughout the production cycle of the broilers. The higher temperature increased IgG levels, especially maternal antibody titers, despite the immunomodulating effect of heat stress until the second week of life.
The effect of dietary vitamin A on antibody production and T cell proliferative response was determined in broilers from 21
to 39 d old. Chicks were fed soybean meal-sorghum diets with levels of supplemented vitamin A from 0 to 13,200 μg/kg retinol
equivalents from hatching and were immunized with β-casein at 21 d of age. T cell proliferation response to β-casein or an
acetone precipitate of antigen to Mycobacterium tuberculosis was determined in vitro at 34 to 37 d old. Antibodies to β-casein in serum were determined every 5 d from 21 d of age. In chicks with no added dietary
vitamin A, antibody production and proliferative response were depressed in comparison with chicks receiving vitamin A. Addition
of small amounts of vitamin A enhanced the responses; both antibody production and proliferative responses increased with
dietary vitamin A until the diet contained 6,660 μg/kg, above which the responses decreased. This suggests that maximal immune
responses in the chick may be achieved at dietary intakes considerably higher than NRC recommendations.
Broiler chickens were examined for the effects of low (400 IU/kg), standard (1,500 IU/kg), or high (15,000 IU/kg) dietary
vitamin A (VitA) levels on immune responsiveness postimmunization to Newcastle disease virus (NDV). A control pair-fed group
(1,500 IU/kg) was included to compensate for the reduced feed intake associated with diet containing the low level of VitA.
Interdigital skin reactions to phytohemagglutinin (PHA) and CD4:CD8 T lymphocyte ratios were significantly reduced in chickens
fed the low VitA diet, whereas their antibody responses to NDV were significantly increased as compared to birds that consumed
the 1,500 to 15,000 VitA diet ad libitum. On the other hand, birds on the high VitA diet had reduced lymphocyte responses
to concanavalin A and pokeweed, but not to PHA. No effect of dietary VitA was observed for natural killer activity, nor on
levels of percentage of cells expressing Class II MHC antigens among groups that consumed feed ad libitum. The results indicated
that both humoral and cellular immune responses were modulated by levels of VitA in the diet, and suggest that VitA-deficient
chickens developed a T helper (Th)2 immune response, whereas the chickens fed highly enriched VitA diet showed a Th1 immune
response.
The whole-body threonine requirement in parenterally fed piglets is substantially lower than that in enterally fed piglets, indicating that enteral nutrition induces intestinal processes in demand of threonine. We hypothesized that the percentage of threonine utilization for oxidation and intestinal protein synthesis by the portal-drained viscera (PDV) increases when dietary protein intake is reduced. Piglets (n = 18) received isocaloric normal or protein-restricted diets. After 7 h of enteral feeding, total threonine utilization, incorporation into intestinal tissue, and oxidation by the PDV, were determined with stable isotope methodology [U-(13)C threonine infusion]. Although the absolute amount of systemic and dietary threonine utilized by the PDV was reduced in protein-restricted piglets, the percentage of dietary threonine intake utilized by the PDV did not differ between groups (normal protein 91% vs. low protein 85%). The incorporation of dietary threonine into the proximal jejunum was significantly different compared with the other intestinal segments. Dietary, rather than systemic threonine was preferentially utilized for protein synthesis in the small intestinal mucosa in piglets that consumed the normal protein diet (P < 0.05). Threonine oxidation by the PDV was limited during normal protein feeding. In protein-restricted pigs, half of the total whole-body oxidation occurred in the PDV. We conclude that, in vivo, the PDV have a high obligatory visceral requirement for threonine. The high rate of intestinal threonine utilization is due mainly to incorporation into mucosal proteins.
Influences of dietary levels of vitamin E fed to hens and their progeny, and routes of SRBC inoculation on antibody responses of diverse populations of chickens were studied. Populations were a commercial broiler sire line (C), 2 commercial broiler dam lines (A and B), and Leghorn lines selected for high (H) or low (L) antibody response to SRBC. Dams from lines A and B were fed diets supplemented with either 10 or 300 IU/kg of vitamin E, whereas dams from lines H and L received only the diet with 10 IU of vitamin E/kg. Progeny from matings of C males with A and B females as well as H and L females mated to males from their respective lines were hatched on the same day and fed diets supplemented with either 10 or 300 IU/kg of vitamin E. Breeders were the same age and eggs were incubated in the same machine. Chicks were inoculated on d 14 intravenously with 0.1 mL of a 0.5% suspension of SRBC or intramuscularly with 0.1 mL of a 25% suspension of SRBC. Antibody response was measured 6 and 14 d later. Chicks received a booster i.m. inoculation of 0.1 mL of 25% SRBC on d 28. Titers were again measured 6 and 14 d later. Level of vitamin E fed to dams did not affect progeny BW or plasma vitamin E levels. Although titers were higher following i.v. than i.m. inoculation, the degree of difference varied among stocks. Dietary vitamin E level interacted with inoculation route with a greater response to the higher than lower level of vitamin E for i.v., but there was no difference for i.m. There were stock x level of vitamin E and stock x route of inoculation interactions for secondary responses to SRBC inoculation. Stock rankings after the first inoculation were not predictive of the rankings after the second inoculation. The 30-fold increase in dietary level of vitamin E resulted in >12-fold differences in plasma levels of vitamin E. Overall, there was a stock-dependent influence of dietary vitamin E on growth and humoral antibody response.
Supplementation of prebiotic compounds, including short-chain fructooligosaccharides (scFOS) has been shown to confer benefits on nutrient utilization, growth, and disease resistance of various animal species through improved gastrointestinal (GI) microbiota. However, potential uses of prebiotics for shrimp have not been defined. A 6-wk feeding trial was conducted in a recirculating system to determine the effects of scFOS supplementation on growth performance, immune functions, and GI microbiota composition of Pacific white shrimp (Litopenaeus vannamei). scFOS was supplemented in a nutritionally complete diet (35% crude protein) at 0.025, 0.0500, 0.075, 0.100, 0.200, 0.400, and 0.800% by weight. After 6 wk of feeding, shrimp fed 0, 0.1, and 0.8% scFOS were sampled for assays of immune function and GI microbiota. Dietary supplementation of scFOS did not improve weight gain, feed conversion ratio, or survival of shrimp. Denaturing gradient gel electrophoresis analysis suggested the intestinal tract microbial community from shrimp fed the basal diet was different from that of shrimp fed the scFOS diets [similarity coefficient (SC) = 74.9%)], although the intestinal tract microbial community from shrimp fed the scFOS-supplemented diets was very similar (SC = 92.3%). All the bacterial species contributing to the GI microbial differences were identified, although most of them are uncultured species. Both total hemocyte count and hemocyte respiratory burst increased (P < 0.05) by incremental dietary supplementation of scFOS (0-0.8%). This study is the first to our knowledge to show that dietary scFOS can selectively support growth of certain bacterial species in the GI tract of shrimp and enhance immunity, which may facilitate development of alternative strategies, including novel probiotics and synbiotics, for shrimp growth and health management.
Fifteen gravid, crossbred gilts were utilized in an experiment to measure the effect of five isonitrogenous dietary treatments (12% crude protein, sorghum-soybean meal; sorghum; sorghum + lysine; sorghum + threonine; sorghum + lysine + threonine) on N balance, colostrum composition and plasma constituents (protein, urea N and IgG). All gilts were fed a standard corn-soybean meal diet from breeding until switched to the sorghum basal diet, on d 60 of gestation. Treatment diets were imposed at d 70. Nitrogen retention, measured between d 103 and 113 of gestation, was improved (P less than .002) by lysine addition. Nitrogen retention was similar (P greater than .10) for gilts fed either the 12% crude protein, sorghum-soybean meal diet or the lysine + threonine-supplemented diet. Plasma protein levels at farrowing were depressed (P less than .06) in those gilts fed sorghum diets without supplemental lysine and plasma urea N was elevated (P less than .10). Plasma protein and plasma urea N were not affected by threonine supplementation (P greater than .10). In contrast, the depression of plasma IgG was ameliorated (P less than .03) by threonine and unaffected by lysine supplementation. These results confirm the hypothesis that lysine is the first limiting amino acid in sorghum protein for gravid gilts as determined by N retention but indicate that threonine is likely the first limiting amino acid for the production of the specific protein, IgG.
Effects of dietary protein or arginine deficiency on constitutive and lipopolysaccharide (LPS)-induced nitric oxide (NO) synthesis were determined in young rats by quantifying urinary nitrate excretion. In Experiment 1, 30-d-old rats (n = 16) were divided randomly into two groups (n = 8/group) and pair-fed on the basis of body weight semipurified isocaloric diets containing 20 or 5% casein. In Experiment 2, 30-d-old rats (n = 24) were divided randomly into three groups (n = 8) and pair-fed on the basis of body weight purified isonitrogenous and isocaloric diets (composed of amino acids) containing 0.0, 0.3 or 1.0% L-arginine. In both experiments, daily collection of urine was initiated 10 d after the start of pair-feeding. On d 17 after the pair-feeding was initiated, LPS (1 mg/kg body wt) was injected intraperitoneally into rats, and urine was collected daily for an additional 7 d. In Experiments 3 and 4, activities of constitutive and inducible NO synthases were measured in macrophages and various tissues from protein- or arginine-deficient rats (n = 6). Body weight was lower in rats fed the 5% casein diet or the 0.0 and 0.3% arginine diets than in those fed 20% casein or 1% arginine, respectively. Dietary protein or arginine deficiency decreased serum concentrations of arginine and urinary nitrate excretion before and after LPS treatment, indicating impaired constitutive and inducible NO synthesis. Protein malnutrition reduced constitutive and inducible NO synthase activities in brain, heart, jejunum, lung, skeletal muscle and spleen, and inducible NO synthase activity in macrophages. Because NO is a mediator of the immune response and is the endothelium-dependent relaxing factor, impaired NO synthesis may help explain immunodeficiency and cardiovascular dysfunction in protein- or arginine-deficient subjects.