Article

Breed and sex differences in growth curves for two breeds of dog guides

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  • Canine Genetic Services, LLC
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Abstract

A desirable dog guide weighs 18 to 32 kg as an adult. Male and female German shepherd dogs and male and female Labrador retrievers were weighed between birth and 18 mo of age, with at least one weight recorded after 290 d of age. Growth curves were constructed from 10,484 observations on 880 dogs using the Gompertz function in the form Wt = W(max)exp(-e[-(t-c)/b]), where Wt is weight at time t, Wmax is mature body weight, b is proportional to duration of growth, c is age at point of inflection, and t is age in days. Estimates for mature body weight were 2.4 +/- .3 kg higher for Labrador retrievers than for German shepherd dogs and 4.7 +/- .2 kg higher for males than for females. Male Labrador retrievers were closest to the upper limit for desirable weight, with an average estimated mature weight of 31.4 +/- .3 kg. Duration of growth, 4b + c, was not different between the breeds; however, the estimate for males was 8 +/- 5d longer than for females. Female Labrador retrievers had the shortest estimate for growth of 319 +/- 6 d. The estimate for age at the point of inflection was 3.6 +/- 1.2 d greater for males than for females, but not different between breeds. A better understanding of growth curves for dog guides may aid in estimating mature weight at a young age, thus allowing earlier breeding and training decisions to be made and increasing genetic change per year.

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... Mathematical models of growth functions can be used to summarize growth data for an individual or a population. The Gompertz function was introduced for this purpose (Winsor, 1932) and has proven useful for estimating growth curves for dogs (Allard et al., 1988;Helmink et al., 2000) and various other species (Menchaca et al., 1996;Emmans and Kyriazakis, 1997;Topal et al., 2004). ...
... A Gompertz function is a nonlinear, sigmoid function with its point of inflection at 36.8% of mature BW. Growth was modeled with the following equation (Helmink et al., 2000), using the NLIN procedure (SAS Inst. Inc., Cary, NC): ...
... Analyses were carried out separately for each breed and sex. Duration of growth was estimated as 4b + c, which describes 98% of the growth phase (Helmink et al., 2000). The derivative of the Gompertz function describes the growth rate. ...
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The main objective of this study was to describe the growth patterns of 4 large dog breeds [Newfoundland (NF), Labrador retriever (LR), Leonberger (LEO), and Irish wolfhound (IW)] raised in domestic environments and concomitant changes in 2 growth-related clinical variables: total serum alkaline phosphatase (ALP) and the circumference of the distal radius and ulna (CDRU). The second objective was to investigate whether these measurements were affected by a range of independent variables like age, sex, litter number, and birth weight. Seven hundred dogs were included in the study, and BW data, separated by breed and sex, were fitted to the Gompertz function. Birth weight, adjusted for litter number, differed significantly between sexes for 3 breeds (LEO, P = 0.004; NF, P = 0.02; LR, P = 0.009) and approached significance for IW (P = 0.07). Estimated mean BW increased rapidly during the first 100 d after birth in all 4 breeds, then plateaued, with maturity being reached between 351 (female LR) and 413 d (male NF). Estimated mature BW ranged from 30.8 kg for the female LR up to 65.7 kg for the male IW. Weight gain, as expressed by the derivative of the Gompertz function, reached its peak in the smallest breed (LR) at the youngest age, 89 d for the females and 95 d for males. Log-transformed BW was significantly related to age, breed, and sex, and the age x sex and age x breed interactions. Within breeds, age, birth weight, and litter number had a significant effect on log-transformed BW. The estimated average CDRU increased from 90 d of age toward a peak at 180 d. Thereafter, CDRU declined and stabilized at about 1 yr of age. The estimated total ALP concentrations decreased from 90 to 360 d of age, after which they stabilized, at mean concentrations varying among breeds from 98 to 131 IU/L. Maximum least squares mean total ALP concentrations were found at 3 mo of age in all breeds, with the greatest least squares mean concentration in the IW breed (713 IU/L). In a mixed model analysis of the complete data set, total ALP was affected (P < 0.001) by age, breed, and the interaction of age x breed. This study described the main factors influencing growth and provided reference data for other studies, including those related to nutrition and disorders of growth.
... A Gompertz function is a nonlinear, sigmoid function, with its point of inflection at 36.8% of mature BW. Growth was modeled with the following equation (Helmink et al., 2000), using the NLIN procedure (SAS Inst. Inc., Cary, NC): ...
... Analyses were carried out separately for sex and groups with and without MI. Duration of growth was estimated by (4b + c), which describes 98% of the growth duration (Helmink et al., 2000). The derivative of the Gompertz function describes the growth rate. ...
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The main objective of this study was to study risk factors affecting metaphyseal irregularities (MI) in the distal radius and ulna of growing Newfoundland dogs. Risk factors studied included the genetic effects, effects of litters, BW, circumferences of the distal radius and ulna (CDRU), and total serum alkaline phosphatase (ALP) concentrations. The study included 118 Newfoundland dogs (60 females, 58 males), derived from 32 litters. Body weight, separated on sex and MI, was fitted to the Gompertz function. Occurrence of MI differed significantly between sexes, with 55% of males and 35% of females affected (P = 0.03). Growth curves for the 2 groups of dogs, with and without MI, diverged after 60 to 70 d, and dogs with irregularities were heavier at maturity than dogs of the same sex without irregularities. In univariate analysis, the litter effect was a significant predictor of MI, explaining 32% of total variability of the MI incidence, but the genetic effects were not significant. However, the latter were significant in bivariate analysis of MI and BW. In the bivariate analysis, the effects of litter on MI and BW were significantly correlated at all observational points except at birth, 180 d, and 536 d. Total ALP concentrations decreased with increasing age, and differences between groups diminished with increasing age, indicating a negative effect of total ALP on MI. Correlation between MI and total ALP concentrations of litters was estimated in a bivariate analysis. This correlation was significant and ranged between -0.34 and -0.62. Similarly, the genetic relationship between total ALP and MI from 120 d of age onward varied between -0.31 to -0.60. However, correlations were only significant at 356 d of age (genetic correlation = 0.60; P = 0.01). The mean CDRU increased from 90 d of age toward a peak at 180 d. Thereafter, CDRU declined and stabilized at about 1 yr of age. The mean CDRU between the groups of dogs with and without MI diverged most at 90 d of age, then was nearly stable until 180 d and gradually declined until 356 d, when the CDRU began to equalize. Metaphyseal irregularities and CDRU levels of litter were significantly correlated. Litter effect was a significant predictor of MI. The effects of litters and the genetic effects on BW and MI were correlated at most phases of the growth of the dog. Similar, but lower, correlations were found for CDRU and MI, and total ALP and MI.
... A Gompertz function is a nonlinear, sigmoid function, with its point of inflection at 36.8% of mature bodyweight. Growth was modeled with the following equation (Helmink et al., 2000), using the NLIN procedure (SAS Inst.Inc., Cary, NC): ...
... Analyses were carried out separately for each breed and sex and groups with and without CHD. Duration of growth was estimated by (4b + c), which describes 98% of the growth duration (Helmink et al., 2000). The derivative of the Gompertz function describes the growth rate. ...
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The study-objective was to measure the effect of weight and growth related parameters on the risk of development of Canine Hip Dysplasia (CHD). The hypothesis was that heavy and fast growing dogs of large sized breeds were at increased risk of development of CHD compared to lighter and slower growing dogs. A prospective cohort study was conducted among dogs of four large breeds: Newfoundland (NF), Leonberger (LEO), Labrador retriever (LR), and Irish wolfhound (IW). The dogs were privately owned with individualized nutrition and environment, and they were followed from birth and throughout the growth period until the official screening for CHD was performed. The study sample consisted of 501 dogs from 103 litters, with the breed distribution 125 NF, 180 LEO, 133 LR, and 63 IW. Because the dogs were clustered in litters a multivariable random effects logistic regression model was used to assess statistically significant growth-related risk factors for CHD. The estimated incidence risk of CHD was 36% in NF, 25% in LEO, 20% in LR, and 10% in IW. Based upon the final multilevel model it appears that the odds of CHD among both LR and IW (odds ratio (OR) 0.22) are about one-fifth of the odds for NF. The odds for LEO (OR 0.60) are not significantly different from NF. There appeared to be an inverse relationship between body weight at 3 months of age and odds of CHD, with an OR of 0.89 (P=0.044). The degree of clustering at the litter-level was high (22.6%) and highly significant (P<0.001). Findings failed to support the hypothesis that heavy and fast growing dogs from four large sized breeds were at increased risk for development of CHD. There might be other unmeasured environmental risk factors for CHD in this cohort of dogs, although the contribution of the genetic variance to the litter-level clustering also needs further investigation.
... Factors such as sex 7,8 and neutering 9À12 may affect nutritional requirements. For example, neutering predisposes cats to obesity, however, the mechanisms by which these effects occur have not yet been fully elucidated. ...
... These results are not fully in agreement with the guidelines of NRC showing that small-sized cats reach maturity at 12 months. 5 Sexual dimorphism in growth has been observed among cats 7,19 and deserves attention in future studies. ...
Article
The aim of this study were (i) to characterize the growth curve in male and female cats, (ii) to associate the growth and metabolizable energy intake (MEI) as an indirect measurement of the energy requirements, and (iii) to determine the short-term effects of neutering on energy intake to maintain the bodyweight in young adult cats. Eighteen 5-months-old mixed breed cats were used in this study (males, n = 7 and BW = 2.2 ± 0.21 kg; females, n = 11 and BW = 2.0 ± 0.16 kg). The cats were fed to supply their metabolizable energy requirement for growth, adjusting the amounts to maintain an ideal body condition score. The animals were weighed every 15 days for 10 months (from five to 15 months-old). At 12 months-old, the cats were gonadectomized and the MEI was recorded for 3 months, up to 15 months old. Second-order, Gaussian, and spherical models were fitted to growth data. Male cats had higher energy intake for growth (MEI = 176.27−0.037t, R² = 0.79) than females (MEI = 166.86−0.044t, R² = 0.62), where t is the age in months. Male cats also reached mature weight later than female cats (16 and 13 months old, respectively). Neutering reduced the energy requirements of male (intact – 116.43 kcal/kg0.67; gonadectomized – 98.65 kcal/kg0.67; p < 0.01) and female cats (intact – 98.65 kcal/kg0.67; gonadectomized – 76.16 kcal/kg0.67; p < 0.01) on average 17.6%. This study suggests that in cats, males and females present different energy requirements since the early growth phases and, this difference remains after neutering in young adults. Female cats reach adult weight earlier than males.
... The average values of body weight for male and female were 21.3 and 19.9 kg, respectively. Helmink et al. (2000) showed that German shepherd and Labrador males were heavier than females for body weight. Similar differences for sex in Labrador retrievers were also observed by Allard et al. (1988). ...
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This study was conducted to characterize the morphological and behavior patterns of Sapsaree dogs. The population (n=8,256) has been constructed since 1990 over 12 generations and managed at the Sapsaree Breeding Research Institute, Gyeongsan, Gyeongbuk province. Eighteen morphological and seven behavioral traits were investigated for 882 individuals. Linear models were applied for each trait by fitting sex, season of birth, hair color or test age. The averages of body weight, body length, body height, and depth of chest were 20.5?2.4\;kg, 57.3?4.2\;cm, 52.1?3.6\;cm, and 21.1?2.4\;cm, respectively. Males had greater estimated values than females for these body conformation traits. The chocolate Sapsarees had greater averages for body weight, body height and chest depth. The older animals (>2 years) had heavier body weight than younger animals. About 54, 69, 97, 39 and 83.3% of the Sapsarees had hairs with yellow color, straight, medium to long, untangled, and longer around eyes, respectively. Also, about 40% brown eye, 43% curly tail, 78% normal jaw, 86% no missing teeth, 90% no dewclaw, and >90% with black nose, pendent ear, tongue without spots were observed. About 95% males were normal in testicles state. The males performed significantly better than the females for majority of the behavioral traits. For nerve stability, affability, wariness, adaptability, sharpness, activity, and reaction during blood drawn about 79%, 73%, 76%, 61%, 70%, 48% and 81% of the Sapsarees performed at desired level. In general, the Sapsarees showed good characteristics for both morphological and behavioral traits, which can be exploited to use the Sapsaree breed as a companion or guide dog.
... Area (R) and perimeter (P) of each worm were measured in pixels automatically with Image Pro Express 4.0 (Media Cybernetics, USA) and used to calculate nematode volume with V GRO (t) ¼ pR 2 /(2P) at time t. These values were used to calculate the growth rate parameter C, which determines the slope of the curve, with the Gompertz growth model (Gompertz, 1825;Helmink et al., 2000): ...
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Phenotypic plasticity and genotype-environment interactions (GEI) play an important role in the evolution of life histories. Knowledge of the molecular genetic basis of plasticity and GEI provides insight into the underlying mechanisms of life-history changes in different environments. We used a genomewide single-nucleotide polymorphism map in a recombinant N2 x CB4856 inbred panel of the nematode Caenorhabditis elegans to study the genetic control of phenotypic plasticity to temperature in four fitness-related traits, that is, age at maturity, fertility, egg size and growth rate. We mapped quantitative trait loci (QTL) for the respective traits at 12 and 24 degrees C, as well as their plasticities. We found genetic variation and GEI for age at maturity, fertility, egg size and growth rate. GEI in fertility and egg size was attributed to changes in rank order of reaction norms. In case of age at maturity and growth rate, GEI was caused mainly by differences in the among-line variance. In total, 11 QTLs were detected, five QTL at 12 degrees C and six QTL at 24 degrees C, which were associated with life-history traits. Five QTL associated with age at maturity, fertility and growth rate showed QTL x environment interaction. These colocalized with plasticity QTL for the respective traits suggesting allelic sensitivity to temperature. Further fine mapping, complementation analyses and gene silencing are planned to identify candidate genes underlying phenotypic plasticity for age at maturity, fertility and growth.
... The general conclusion drown from this results is that at higher t irr and T inc higher hemolysis rate takes place. In the basis of Helmink et al. [13] calculation, using the same form of Gompertz, for the time required to 98% hemolysis was in good agreement with the experiment values, 9.7% ± 2.8 at 24°C and 11.93% ± 2.5 at 37°C for the data shown in Table 1. These results showed that the Gompertz analysis technique adapts to study the effects of t irr , T irr , and T inc on the photohemolysis process at different conditions as a best-fit model with minimum parameters and minimum errors. ...
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Photosensitization by protoporphyrin IX (PpIX) is accelerated at different irradiation temperatures, different dark incubation temperatures (T inc) and different irradiation times. The applicability of Gompertz function to the fractional photohemolysis ratio, a and the rate of fractional photohemolysis, b is found to be the most appropriate model to fit the experimental data with minimum parameters and minimum errors. The reduction in Gompertz parameters, the fractional ratio values of a, and increase in the fractional rate values b, for 20 μM PpIX irradiated with black light at low irradiation temperature 5°C and higher T inc 37°C was noticed. The parameter a has higher values at lower irradiation time and lower irradiation temperatures which indicates a longer photohemolysis process and longer t 50. Values of the parameter b were found to be strongly temperature-dependent, and always increase with increasing irradiation time and T inc with lower values at lower irradiation time and lower T inc. There are no significant changes in the lysis of RBCs process at irradiation temperatures equal to or higher than 35°C. Similarly, no significant change on t 50 at higher irradiation time at T inc 24 and 37°C. In conclusion, Gompertz analysis technique adapts to study the photohemolysis process at different conditions as a best-fit model.
... In addition, sex-ratio differences for the different breed groups studied (Table 1) complicate interpretation, because males and females may have different growth patterns. Sex differences were reported in previous studies (10,11) with males taking longer to reach adulthood than females. Whether this sex effect occurs in all breeds or has any practical impact remains to be seen, but it may explain some of the differences observed here including the separation of Cocker Spaniels from other smallsized breeds (sex-specific data not shown). ...
... Data were recorded for German shepherd dogs and Labrador retrievers raised by the Seeing Eye from 1968 to 1997, including 25,494 weight observations on 4,427 dogs and a single height observation on 2,420 dogs. Data collection and management of the dogs was previously described (Helmink et al., 2000). Traits evaluated were birth weight, 42-d weight, mature weight, and mature height. ...
Article
A desirable dog guide weighs 18 to 32 kg and measures 53 to 64 cm in height at the withers as an adult. Heritabilities and genetic correlations were estimated for birth weight, 42-d weight, mature weight, and mature height for 2,334 German shepherd dogs and 2,028 Labrador retrievers raised by the Seeing Eye, Inc., Morristown, NJ, from 1979 to 1997. Data included 5,006 observations for German shepherd dogs from 113 dams and 33 sires and 4,123 observations for Labrador retrievers from 89 dams and 29 sires. A mixed effects model was considered with sex and birth year as fixed effects. Random effects were animal, maternal, and litter incorporating all pedigree information available. A derivative-free REML method was used to estimate parameters. The maternal component was higher than the additive genetic component for birth weight. Heritability of mature weight was estimated as 0.57 +/- 0.07 for German shepherd dogs and 0.44 +/- 0.07 for Labrador retrievers. Mature height heritability was estimated as 0.35 +/- 0.08 for German shepherd dogs and 0.46 +/- 0.08 for Labrador retrievers. Selection for lighter dogs at maturity is predicted to decrease the average mature height, and selection for taller dogs at maturity is predicted to increase the average mature weight. The estimated genetic parameters will aid in the development of strategies to increase the probability of breeding dogs for optimum mature size.
... These rules are potentially important for guide dogs for several reasons. First, regular and consistent feeding will assist in maintaining an appropriate weight for the dog throughout its working life (Helmink et al., 2000;Hawthorne et al., 2004). Second, providing clear and consistent indication that the owner is in control of the food resource will also reinforce the owner's status and maintain the dog's general level of obedience (Pageat, 1999). ...
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... Body mass was determined to the first decimal using a traditional scale. A growth curve was constructed by plotting body mass against age using the Gompertz equation in the form: m t = m max exp(−exp [−(t-c)/b] ), where m t is mass at time t, m max is mature body mass, b is proportional to duration of growth, c is the age at point of inflection (i.e., 36.8% of mature body mass) and t is age in weeks (for details, see [36]). Growth duration to reach 98% of the mature body mass was estimated as 4b+c. ...
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... While this mass is well within the range of that estimated for the Holocene dogs from this region (Table 6), the Ust'-Khaita canid was only 5-8 months old at death and thus had not reached adult body size. Studies of modern dogs indicate they rapidly increase in body mass for the first three months or so of their lives, with the rate body mass increase markedly slowing after this point, with many breeds reaching mature body weights at roughly one year of age (Allard et al., 1988;Hawthorne et al., 2004;Helmink et al., 2000;Tangerud et al., 2007;Voorhout et al., 1994); both dogs and wolves can of course increase in body mass after first reaching adulthood (c.f., Mech, 2006). If this canid were to have lived to adulthood (~1 year of age), it is likely it would have weighed somewhat more than its current estimated mass. ...
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Previously developed regression formulae for estimating body mass in dogs and wolves based on cranial and mandibular dimensions are evaluated using modern canid specimens of known weight at death. Some of these equations proved reliable, but others have large standard errors of estimate and likely produce unreliable mass estimates. New sets of equations for estimating body mass in dogs and wolves are produced using our datasets, including a set of equations developed from combining the dog and wolf biometric data into a single population. The resulting regression equations allow body mass to be estimated from a series of cranial and mandibular dimensions with relatively low errors. Further, our datasets include larger numbers of specimens of larger ranges of body mass than in these previous studies. When the equations are applied to a suite of dogs and one wolf from Eastern Siberia, several patterns emerge. First, hunter-gatherers’ dogs in this region vary widely in terms of body size, even within a limited geographic area and time period. Some were quite large, similar in size to modern Siberian huskies. Second, pastoralists’ dogs are less variable in terms of body mass, but this may reflect the nature of our samples. In particular, pastoralists’ dogs nearly all were sacrificed juvenile dogs, some of which appear to have been eaten. These dogs seem to have been approach adult body size when they were selected for sacrifice. Finally, our findings help to highlight the need for further refinement in methods used to study ancient canid remains.
... This is in agreement with Sorensen et al. (2003) who applied the multiphasic logistic growth function with three phases of mink. The Gompertz has been proven to be useful for estimating growth curves for dogs (Allard et al., 1988;Helmink et al., 2000) and various other species (Menchaca et al., 1996;Emmans & Kyriazakis, 1997;Topal et al., 2004). ...
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The objective of this study was to estimate and compare the growth curve parameters for live weight of standard black, brown, mahogany, Hedlund white and sapphire minks. The data were collected from five colour types in the period from seven days to 24 weeks of age. Three hundred mink (about 60 of each colour types) were used. Six different non-linear models, namely Logistic, Gompertz, Brody, Richards, Bridges, and Janoschek were used to define the growth curves of the mink. Models were compared using coefficients of determination (R 2 values), the Akaike's information criterion (AIC) and the Bayesian information criterion (BIC). The R 2 were high for all models, ranging from 0.923 to 0.985 for different breeds of mink. Comparing the models by AIC, BIC values and the residuals showed the following results. Three of the models fitted the growth curves very well. Colour type differences were observed in the growth parameters of mink. The brown, mahogany and sapphire was observed to be late maturing and lighter at maturity, while the standard black and Hedlund white had a higher growth rate, reached maturity earlier and attained a heavier mature weight.
... A better understanding of growth curves for dog guides may aid in estimating mature weight at a young age, thus allowing earlier breeding and training decisions to be made and increasing genetic change per year (Helmink et al., 2000). Most puppies live together with the mother and their siblings for the first eight weeks of their life. ...
... where Wt = weight at time t, Wmax = mature body weight, t = age in days, c = age at the point of inflection, and b = constant proportional to the duration of growth. The parameters discussed by the authors [10], [11] have been considered for generating growth-generated data. Furthermore, the following assumptions have been made for healthy pets, the bodyweight of the pet continuously grows up to certain age. ...
Conference Paper
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The rapid development of artificial intelligence, internet of things, and digital information processing technology has a huge impact on our daily life with smart devices and wearables. The well-being of companion animals has become a large challenge. An increasing number of pet owners, their emotional attachment with their pet, and the 21st-lifestyle importantly need the safety and welfare of pets by harnessing a smart technological approach. This paper analysis the virtual dataset of 2 dog breeds determining pet health conditions. The body weight growth, body temperature, heart rate, eating habits, activity, sleep, and urine pH have been analyzed using different machine learning models: wide neural network, quadratic & linear support vector machine, fine tree, and logistic regression. The results are compared and the evaluation of the robustness is tested with two independent datasets. The developed model will be helpful for pet health care applications.
... Although differences in postweaning growth curves and adult weights between females and males have been demonstrated in dogs (Helmink et al., 2000) and in cats (Moik and Kienzle, 2011), no sexual dimorphism in birth weights or early growth was evidenced in our study. Interestingly, growth during the first 2 d of life was not found to be associated with birth weight, whereas in many other species an accelerated growth occurs, compensating the lower weight at birth (Binkin et al., 1988;Moik and Kienzle, 2011). ...
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Breeding kennels face a high rate of neonatal mortality, on which the impact of nutrition remains to be determined. This study was designed to evaluate the impact of birth weight (reflecting intrauterine growth) and early growth rate (reflecting colostrum intake) on risk of neonatal mortality in puppies and to determine the critical thresholds of both parameters. Puppies from various breeds were weighed at birth ( = 514) and at 2 d of age, and the growth rate over that period (early growth rate) was calculated for all survivors ( = 477). Linear mixed models evaluated the effect of birth weight on mortality between birth and 2 d of age and the effect of both birth weight and early growth rate on mortality between 2 and 21 d of age. Birth weight was influenced by litter size ( = 0.003), with more low-birth-weight puppies (the lightest 25% within a breed size) in large litters compared with smaller litters. Mortality over the first 2 d after birth was associated with birth weight ( < 0.001), with 81.1% of dying puppies characterized by a low birth weight. Mortality between 2 and 21 d of age was not related to birth weight but was found to be associated with early growth rate ( < 0.001), with higher risk of death in puppies with growth rate at or below -4% after the first 2 d of life. This study demonstrates the differential effect of intrauterine nutrition impacting mortality during the first 2 d of life and that of colostrum intake impacting mortality until 21 d of life. Birth weight and early growth rate thresholds provided in this study allow identification of puppies at risk, whereby provision can be made for adequate nursing to increase their chances to survive.
... Our study highlights not only the importance of breed size-specific study, but also breed-specific, as birth weight was demonstrated significantly different within the same breed-size puppies. For example, adult body weights of the German Shepherd Dog, Boxer and Golden Retriever are similar, ranging from about 25 to 30 kg (Helmink et al., 2000;Hawthorne et al., 2004;Trangerud et al., 2007;Posada et al., 2014), whereas their average birth weights are quite different (506 g, 464 g and 395 g, respectively). ...
... By solving the maximum-likelihood estimates analytically, the dimension of the optimization problem can be reduced, both in the case of discrete and continuous data. Gompertz model has been used to analysis the growth of mice (Kurnianto et al., 1998), dog (Helmink et al., 2000) sheep (Suparyanto et al., 2001), rabbit (Blasco et al., 2003), lamb (Lambe et al., 2006), pig (Strathe et al., 2010) and cattle (Forni et al., 2009;Budimulyati et al., 2012). Several researches about growth of rabbit were analysed with Logarithmic model (Rao et al., 1997), Stochastic model (Sampaio et al., 2005) and General Linear Mixed Model (McNitt and Lukehfar, 2005). ...
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An experiment was conducted to compare the growth curve of rabbit. Three breeds of rabbit,namely Indonesian Local Rabbit (IL), Flamish Giant (FG) and Rex (R) were used in the study.Individual body weights of each breed was measured from birth to 63 days of age with 3-days interval.Those periodical data were separated into different sex, be then it was averaged to analysis growthpattern. Growth curve parameters were estimated to fit growth data. There was no difference in bodyweight between sexs within breed. Indonesian local rabbit had the lowest body weight. The resultsshowed that growth curve paramaters among three breeds were significantly different (P<0.05) for bothsexes. FG had the highest value of asymptotic mature weight, followed by R and IL. In conclusion,Gompertz model was excellent fit for the growth data in rabbit with a high coefficient determination (R2= 0.999).
... Mammals have a characteristic growth pattern in which juveniles grow rapidly to reach a maximum adult size, at which point growth abruptly ceases (determinate, truncated growth). This typically results in a sigmoid individual growth curve (Fig. 1) with a definite plateau (e.g., mice and rats [Eisen 1976]; Peromyscus maniculatus [Dice and Bradley 1942]; Sorex unguiculatus [Nesterenko and Ohdachi 2001]; domestic dog breeds [Helmink et al. 2000]; Monodelphis domestica [Cothran et al. 1985]; dolphins [Fernandez 1998]). The unique mammalian apomorphy of lactation permits rapid and sustained postnatal growth throughout juvenile and subadult stages. ...
Article
One of the major evolutionary transitions of the mammaliaform lineage was the origin of a typically mammalian pattern of growth. This is characterized by rapid juvenile growth followed by abrupt cessation of growth at adult size and may be linked with other important mammaliaform apomorphies of dental replacement and morphology. Investigation of growth patterns in the tritylodontid cynodont Oligokyphus and the basal mammaliaform Morganucodon provides insight into this crucial transition. We collected mandibular depth measurements from large samples of Morganucodon and Oligokyphus and constructed distributions of mandibular depth versus frequency for each species. These were compared with distributions from species from three different growth classes of extant amniote: testudines + crocodilians, mammals + birds, and lepidosaurs. Discriminant function analysis was used to differentiate between known growth classes by using different combinations of three measures of mandibular depth distribution shape (skew, kurtosis, and coefficient of variation) as proxies for different juvenile and adult growth patterns. Classification of the fossil species showed that Morganucodon closely resembled extant placental mammals in having rapid juvenile growth followed by truncated, determinate adult growth. Oligokyphus showed intermediate growth patterns, with more extended adult growth patterns than Morganucodon and slightly slower juvenile growth. This suggests a gradual evolution of mammalian growth patterns across the cynodont to mammaliaform transition, possibly with the origin of rapid juvenile growth preceding that of truncated, determinate adult growth. In turn, acquisition of both these aspects of mammalian growth was likely necessary for the evolution of diphyodont tooth replacement in the mammaliaform lineage.
... Although differences in postweaning growth curves and adult weights between females and males have been demonstrated in dogs (Helmink et al., 2000) and in cats (Moik and Kienzle, 2011), no sexual dimorphism in birth weights or early growth was evidenced in our study. Interestingly, growth during the first 2 d of life was not found to be associated with birth weight, whereas in many other species an accelerated growth occurs, compensating the lower weight at birth (Binkin et al., 1988;Moik and Kienzle, 2011). ...
Article
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Breeding kennels face a high rate of neonatal mortality, on which the impact of nutrition remains to be determined. This study was designed to evaluate the impact of birth weight (reflecting intrauterine growth) and early growth rate (reflecting colostrum intake) on risk of neonatal mortality in puppies and to determine the critical thresholds of both parameters. Puppies from various breeds were weighed at birth (n = 514) and at 2 d of age, and the growth rate over that period (early growth rate) was calculated for all survivors (n = 477). Linear mixed models evaluated the effect of birth weight on mortality between birth and 2 d of age and the effect of both birth weight and early growth rate on mortality between 2 and 21 d of age. Birth weight was influenced by litter size (P = 0.003), with more low-birth-weight puppies (the lightest 25% within a breed size) in large litters compared with smaller litters. Mortality over the first 2 d after birth was associated with birth weight (P < 0.001), with 81.1% of dying puppies characterized by a low birth weight. Mortality between 2 and 21 d of age was not related to birth weight but was found to be associated with early growth rate (P < 0.001), with higher risk of death in puppies with growth rate at or below -4% after the first 2 d of life. This study demonstrates the differential effect of intrauterine nutrition impacting mortality during the first 2 d of life and that of colostrum intake impacting mortality until 21 d of life. Birth weight and early growth rate thresholds provided in this study allow identification of puppies at risk, whereby provision can be made for adequate nursing to increase their chances to survive. © 2015 American Society of Animal Science. All rights reserved.
... We may assume that a younger and larger sized male dog might have a higher residual potential growth at 5 months. 21 According to this statement, the younger and the larger the patient, the greater the change achieved. The larger/younger the patient, the more frequently the TPA should be checked after TPCHE. ...
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The aim of this study was to report a case of caudal cruciate ligament rupture in a 9-year-old dog who underwent juvenile tibial plateau cranial hemiepiphysiodesis that was performed to treat a partial cranial cruciate ligament rupture and excessive tibial plateau angle. A 9-year-old, 45 kg, male Bernese Mountain dog was referred for a non-traumatic acute right pelvic-limb lameness. At the age of 5 months, the dog underwent bilateral tibial plateau cranial hemiepiphysiodesis to treat a bilateral partial cranial cruciate ligament rupture and excessive tibial plateau angles. At clinical examination, a caudal tibial subluxation of the right stifle was detected. The right tibial plateau angle was 3 degree. Arthroscopy confirmed a complete caudal cruciate ligament rupture. The cranial cruciate ligament was partially torn. A diagnosis of caudal cruciate ligament rupture 8.5 years post juvenile tibial plateau hemiepiphysiodesis was made. A tibial plateau overcorrection might have contributed to caudal cruciate ligament rupture in this dog.
... Mammals have a characteristic growth pattern in which juveniles grow rapidly to reach a maximum adult size, at which point growth abruptly ceases (determinate, truncated growth). This typically results in a sigmoid individual growth curve (Fig. 1) with a definite plateau (e.g., mice and rats [Eisen 1976]; Peromyscus maniculatus [Dice and Bradley 1942]; Sorex unguiculatus [Nesterenko and Ohdachi 2001]; domestic dog breeds [Helmink et al. 2000]; Monodelphis domestica [Cothran et al. 1985]; dolphins [Fernandez 1998]). The unique mammalian apomorphy of lactation permits rapid and sustained postnatal growth throughout juvenile and subadult stages. ...
Article
One of the major evolutionary transitions of the mammaliaform lineage was the origin of a typically mammalian pattern of growth. This is characterized by rapid juvenile growth followed by abrupt cessation of growth at adult size and may be linked with other important mammaliaform apomorphies of dental replacement and morphology. Investigation of growth patterns in the tritylodontid cynodont Oligokyphus and the basal mammaliaform Morganucodon provides insight into this crucial transition. We collected mandibular depth measurements from large samples of Morganucodon and Oligokyphus and constructed distributions of mandibular depth versus frequency for each species. These were compared with distributions from species from three different growth classes of extant amniote: testudines + crocodilians, mammals + birds, and lepidosaurs. Discriminant function analysis was used to differentiate between known growth classes by using different combinations of three measures of mandibular depth distribution shape (skew, kurtosis, and coefficient of variation) as proxies for different juvenile and adult growth patterns. Classification of the fossil species showed that Morganucodon closely resembled extant placental mammals in having rapid juvenile growth followed by truncated, determinate adult growth. Oligokyphus showed intermediate growth patterns, with more extended adult growth patterns than Morganucodon and slightly slower juvenile growth. This suggests a gradual evolution of mammalian growth patterns across the cynodont to mammaliaform transition, possibly with the origin of rapid juvenile growth preceding that of truncated, determinate adult growth. In turn, acquisition of both these aspects of mammalian growth was likely necessary for the evolution of diphyodont tooth replacement in the mammaliaform lineage.
... This study highlights the importance of breed-specific analysis because birth weight was significantly different between puppies from different breeds inside the same breed size. For example, the German Shepherd, the Boxer and the Golden Retriever are in the large size category with adult body weight ranging from about 25 to 30 kg (Helmink et al., 2000;Hawthorne et al., 2004;Trangerud et al., 2007;Posada et al., 2014). However, even though they are in the same size category, their average birth weights were significantly different (506, 464 and 395 g for respectively German Shepherd, Boxer and Golden Retriever; Table 2). ...
Article
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In numerous species, low birth weight is a risk factor for neonatal mortality. In the canine species, definition of a low birth weight is complex due to the huge interbreed variability in size. To identify puppies at higher risk of neonatal death, data from 6,694 puppies were analysed. The data were collected from 75 French breeding kennels, examining 27 breeds and totaling 1,202 litters of puppies. Generalised linear mixed models allowed to identify birth weight, birth weight heterogeneity within the litter, and size of the breeding kennel as significant risk factors for neonatal mortality. Receiver Operating Characteristics (ROC) and classification and regression tree (CART) analyses were combined to define breed specific thresholds for birth weight allowing the identification of puppies at higher risk of neonatal mortality. Due to differences in birth weights between breeds, including when belonging to the same breed size, analyses were conducted at the breed level. First, ROC analysis thresholds were successfully established for 12 breeds (area under the ROC ≥ 0.70; sensitivity ≥ 75%; specificity: 45-68%) and they ranged from 162 g in the Maltese to 480 g in the Bernese Mountain dog. Secondly, CART analysis thresholds from 22 breeds ranged from 105 g in the Maltese and 436 g in the Boxer. Puppies were grouped into three categories according to birth weight: low, moderate and high risk of neonatal mortality (higher than the ROC threshold, between ROC and CART thresholds, and lower than the CART threshold respectively). In the current study, 44% of the puppies were classified as at moderate risk and 5.3% for a high risk of neonatal mortality. Thresholds defined by CART analysis (and not ROC analysis) were used to define low birth weight puppies and were sometimes quite different between breeds with similar birth weight distributions suggesting a variable relationship between birth weight reduction and neonatal death. These results allow the identification of puppies at an increased risk of neonatal death, thus requiring specific nursing to improve their chances of survival. With these high risk puppies identified, both animal welfare and kennel productivity is predicted to improve.
... Our findings did not reveal any difference between male and female puppies in birth weights or growth rates in the first six days of life, although a sexual dimorphism in postweaning growth curves has been described in dogs [41] and in cats [40]. ...
Article
Puppy neonatal mortality may be related to low birth weight, which has been shown in humans to be linked to placental factors. The relation between the newborn puppy and the placental characteristics has been poorly investigated in dogs. Twenty bitches, 9 toy-sized (i.e. < 5 Kg) and 11 small-sized (i.e. 5 to 10 Kg), were included in this study. During natural delivery or c-section, puppies were identified and their order of birth, sex and weight were recorded. Puppy weights were registered at birth and daily until Day 6. Placentas were weighed after removal of extraplacental adnexa, after which a photo was taken and morphometrically assessed. The Total Placental Area (TPA) and the Transfer Zone Area (TZA) were calculated and their surface expressed in mm2. Immunohistochemistry with monoclonal mouse anti CD31 antibody was used to identify fetal and maternal vessels in the placental labyrinth zone. A vascularization index (VI) was determined for each placenta and the Total Vascular Area (TVA) was estimated. Puppies' birth weight correlated positively with placental weight (P < 0.001, r = 0.689). A positive correlation was found between the puppies' birth weight and TPA (P < 0.001, r = 0.786), TZA (P < 0.001, r = 0.772), and TVA (P < 0.001, r = 0.482). A positive correlation was also found between placental weight and TPA (P < 0.001, r = 0.661), TZA (P < 0.001, r = 0.583), and TVA (P < 0.001, r = 0.333). In the small-sized breeds, the placentas of low-weight puppies were lighter and had a smaller TZA and TVA (P < 0.05). The VI was higher in the placentas of the toy-sized compared to small-sized bitches (P < 0.01). No effect of parity, litter size, or sex of the puppy was observed on birth weight or growth rates on Day 6. The growth pattern of low-weight puppies did not differ from that of the other puppies during the first 6 days of life. As in humans, placental weight, the extension of the transfer zone and placental total vascular area correlates closely with the puppies' birth weight in normal pregnancies. Our data could represent reference values for placental weight, TZA, TVA and VI in toy and small-sized dog breeds.
... Some studies have reported different growth rates for males and females, with males taking longer to reach adult body weight than females (Allard, Douglass, & Kerr, 1988;Helmink, Shanks, & Leighton, 2000). Though male puppies are heavier than females at 6 weeks old and this difference is maintained until adulthood (Booles, Poore, Legrand-Defretin, & Burger, 1994;Salt et al., 2017), we did not observe any sexual dimorphism within the first three weeks after birth. ...
Article
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Neonatal mortality in puppies is highly variable, with large scale surveys still reporting average values around 10% –15%. Weight measurement is the simplest way to monitor the development of the puppies, and a weight loss during the first 48 hr has been recognized as one of the factors that puts puppies at a higher risk of neonatal mortality. However, little is known about what constitutes optimum growth up to 3 weeks. In this study, a mathematical formula with the form P = P0 exp (0.13084 x ‐ 0.001616 x2), where P is weight on Day x and P0 is weight on Day 0, obtained by multiple linear regression, is presented and validated with data from 345 puppies belonging to 60 litters of 19 different breeds, from toy to giant size, showing that it appropriately describes maximum puppy growth rate during the neonatal period for all breeds. This formula is in agreement with previous studies and generic recommendations that can be found in the literature on puppy growth from birth to 21 days regarding relative daily weight gain. It can be easily introduced in a spreadsheet or used to build growth charts that can help the breeder or the veterinarian in monitoring and evaluating puppy growth during the neonatal period. Although deviations from the maximum growth rate can now be quantified, there is still a need to determine the limits beyond which supplementary feeding is advised/required. Maximum puppy weight growth rate during the first 3 weeks can be described by an equation of the exponential type.Puppy weight can be predicted with this equation given weight on Day zero (birth day) and age of the puppy This equation is shown to properly describe puppy weight increase, irrespective of birth weight and breed
... Elmaz, e-mail: elmaz@mehmetakif.edu.tr of its adult behaviour (Scott andFuller 1998, Case 1999). A better understanding of growth curves for dog breeding may aid in estimating mature weight at a young age, thus allowing earlier breeding and training decisions to be made and increasing genetic change per year (Helmink et al., 2000). The number of dog breeder establishments that are registered and systematic in Turkey is quite limited. ...
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This study was carried out to determine growth and survival characteristics of Kangal Turkish shepherd puppies during suckling period. Body weight, survival ratio and some body measurements of the Kangal Turkish shepherd puppies during this period were examined. In addition, effects of mother's age, litter size and sex of the puppy on these body measurements were investigated. The study was conducted on 38 puppies (12 female, 26 male) born from six Kangal Turkish Shepherd bitches. The average live weights of the puppies were measured to be 1008 g at the end of the first week and 3871 g at the end of the eighth week. The survival ratio was 100% at the end of the 8th week. Some body measures of the puppies such as head length, head girth, ear length, chest girth, tail length, body length, shoulder height, rump height, front wrist girth, and back wrist girth were 15.07 cm, 24.61 cm, 7.22 cm, 35.36 cm, 16.27 cm, 27.77 cm, 27.32 cm, 26.31 cm, 7.38 cm and 6.73 cm at the age of weaning (52nd day), respectively. Chest girth, tail length and shoulder height of the puppies born from 8 years old mothers were found to be higher compared to the puppies born from 1 and 3 years old mothers (P < 0.001). The effect of birth type on the body measures at the 38th day was determined to be significant (P < 0.001). The highest values were obtained from the mothers with five puppies and the lowest values from the mothers with seven puppies. When the comparison is made in terms of sex, even though the male puppies were larger than the female puppies, the difference was not statistically significant.
... Moreover, for the individual puppy, early contact with humans may have beneficial future effects. The weight curves and growth rate of dogs have been investigated in several studies [2][3][4]. Weight has an impact not only on health [5] but also on certain behavioral aspects, with larger female puppies being more active and explorative than their smaller counterparts [6]. The growth of puppies after weaning age has been investigated [7,8]. ...
Article
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Weight at birth (bBW) and early weight gain have been linked to the risk of neonatal mortality. Pups are described to be of low bBW if weighing less than one standard deviation (SD) below the mean. Most studies classified breeds according to their expected adult bodyweight. Our aim was to evaluate the breed specificity of these parameters. We assessed the bBW of 213 puppies of Bernese Mountain Dog (BMD), Tibetan Terrier (TT), and Lhasa Apso (LA) breeds, as well as the neonatal growth rate of 133 puppies of BMD and TT. BMD puppies were born relatively smaller than puppies of TT and LA (p ≤ 0.0001) and gained less weight than TT puppies during the first 14 days (p ≤ 0.05). Litter size had a significant impact on bBW and daily gain until the onset of the third week for BMD (p < 0.0001 and p = 0.0005, respectively) and TT (p = 0.0003 and p = 0.0064, respectively). When using bBW means and SD specifically assessed according to breed, 29 out of the 213 neonates of our study were judged as being of low bBW, whereas, when using the classical criteria (based on breed groups), the number of low bBW pups was 160 of 213. These results suggest that evaluations of bBW and neonatal growth should be performed in a breed-specific manner.
... Although differences in post-weaning growth curves and adult weights between females and males have been demonstrated in dogs (Helmink et al., 2000) and in cats (Moik and Kienzle, 2011), no sexual dimorphism in birth weights or early growth was evidenced in our study. Interestingly, growth during the first two days of life was not found to be associated with birth weight, whereas in many other species an accelerated growth occurs, compensating the lower weight at birth (Binkin et al., 1988;Moik and Kienzle, 2011). ...
Thesis
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Neonatal mortality in dogs (within the first three weeks after birth) accounts on average for 20% of puppies born alive, being thus responsible for a great economic loss to dog breeders. However, immunological and nutritional determinants of puppies survival are poorly described. This dissertation thus investigated the risk factors of neonatal mortality in dogs, and in particular the importance of colostrum intake for survival. The first part of results revealed a strong association between early growth rate (during the first two days of life) and neonatal losses. As early growth rate reflects the colostrum intake, the role of colostrum was then addressed. Passive immune transfer was shown to affect mortality rate, with serum IgG concentration at two days of age lower than 2.3 g/L being characterized as in deficit of maternal immunoglobulins. Similar lack of immunoprotection was observed for a specific canine pathogen (canine parvovirus type 2), as puppies with low antibody titers at two days of age seroconverted or underwent parvovirus infection significantly earlier than puppies with higher titers. Energy intake, evaluated via blood glucose concentration at 24h of life, was also found associated with survival: puppies with low glucose concentration (≤ 92 mg/dl) were found at higher risk of death. Besides the strong relationship between colostrum ingestion, providing passive immunity and energy, the impact of birth weight and vitality at birth (evaluated via Apgar score) on puppies’ survival was also evidenced. Colostrum immune quality (evaluated via IgG concentration), although not directly linked with the risk of neonatal death, was found of great variability, most probably putting some puppies at a risk of passive immune deficit. The present study contributed to the knowledge about the risk factors of mortality to be controlled in breeding kennels. Results provided in this work revealed the crucial role of the fetal growth, course of parturition and intake of the colostrum for the newborn dog. Regular weighing of newborns can be advised as a practical application for dog breeders, as it allows to identify puppies at a higher risk of death and to provide puppies with additional nursing and veterinary care.
Conference Paper
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Regardless of the mobile applications available in smartphones, the veterinary hospitals in Sri Lanka still use the manual books to fill the vaccination schedule and keep track of pet care. This research is an attempt to change this tradition by introducing a smart system for dogs. The system can be used both by dog lovers and veterinary doctors. In this study, new proposed application plan is to replace the traditional method with a method that can store the information into a system and make it available for the users to take care of the dog. Since the dog's birth, the information can be stored and it will assist the pet owners. Unlike other applications available, the advantage of this application is that the user can choose applications to be used individually or integrated according to their choice.
Article
This study demonstrates the long-term effects of very early embryonic exposure to a single dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (0, 10 and 20 ng/egg), administered before the beginning of embryonic development, on growth and reproductive performance in laying hens. Hatchability and body weight gain from 11 weeks onwards were significantly depressed in 20 ng treated hens. All hens started laying egg at around the same age and the laying performance of TCDD-treated hens was normal. No disturbances in the age-related pattern and concentrations of oestradiol, LH or FSH in plasma could be found but mean progesterone concentrations were significantly lower in 20 ng treated hens. Moreover, follicular distribution was changed with less small white follicles and smaller yellow follicles, which probably resulted in the lower egg weight of the 20 ng treated hens. At 43 weeks of age, hens treated in ovo with TCDD showed a retained right oviduct, mostly filled with clear fluid. From these results, it seems that in ovo exposure to TCDD interferes in the right oviduct regression during embryonic development and induces some changes in follicular distribution but without impairment of reproductive performance in the adult laying hen.
Article
ASTRACT: Hanoverian, Brazilian Showjumper, English Thoroughbred and Crossbred horses reared by the Brazilian Army were weighed and measured from six months of age to adult. In total 4,860 measurements on 1,445 horses were available. General curves were estimated as a function of time by the Gompertz, Brody, Logistic, Weibull and Richards curves, using PROC NLIN procedures of SAS ®. The Richards Curve did not converge for weight or height of any of the genetic groups or sexes. The logistic curve did not converge for any of the weight traits while the Gompertz also did not converge for height in several groups. R2 varied between 0.55 for weight in females of the crossbred group to 0.92 for males of the same group. For the height traits the highest R2 (0.66) was found for female Hanovarian horses and lowest for males of the same breed (0.12). In general the curves estimated similar values for asymptotic height and weight, except for Logistic curve, which also showed lowest R2 and highest error. Results for the Weibull and Brody curves were similar in all cases so where possible the Brody curve was selected as the best curve as it had less parameters. The Gompertz curve tended to underestimate mature weights and height. Estimates for both weight and height were in general higher in males than for females. In most cases the b parameter was shown to account for < 0.0001% of the variation in the curve shape. The k parameters, which indicate maturity, were of similar magnitude for the Brody, Gompertz and Weibull curves, for both height and weight within breed. This parameter indicated that there is little difference in maturation rates between males and females. __________________________________________________________________________________ RESUMO Cavalos das raças Hanoveriana (HA), Brasileiro de Hipismo (BH), Puro Sangue Inglês (PSI) e mestiços (PSIxBH) criados pelo Exército brasileiro foram pesados e medidos de seis meses de idade até adulto. Realizaram-se 4.860 medidas em 1.445 cavalos. Estimaram-se curvas de crescimento gerais usando os modelos de Gompertz, Brody, Logistic, Weibull e Richards, segundo o procedimento PROC NLIN do programa SAS ®. A curva de Richards não convergiu para peso nem altura para nenhum dos grupos ou sexos avaliados. A curva logística não convergiu para os pesos, enquanto o modelo de Gompertz não convergiu para altura em vários grupos. R2 variou entre 0,55 para peso em fêmeas mestiças até 0,92 em machos do mesmo grupo. Para altura, o maior R2 (0,66) foi para machos Hanovarianos e o menor para fêmeas da mesma raça (0,12). Em geral, as várias curvas estimaram a mesma altura e peso adulto, exceto a curva logística, que teve o menor R2 e mais alto erro dentro de cada grupo. Resultados para as curvas de Weibull e Brody foram similares em todos os casos. A curva de Brody foi selecionada como a melhor, porque possui menos parâmetros. A curva de Gompertz teve a tendência de subestimar pesos e alturas adultos. Estimativas para ambos as características foram mais altas em machos que fêmeas. No maior parte dos casos, o parâmetro b levou em consideração menos que 0,0001% da variação em forma da curva. Os parâmetros k, indicando maturidade, foram de magnitude similar para as curvas de Brody, Gompertz e Weibull, para altura e peso dentro de raça, o que indicou pouca diferença entre machos e fêmeas para taxa de maturação entre sexos.
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This study was carried out to establish the body weight, survival rate and some body measurements in German Shepherd puppies during the suckling period. The puppies were each weighed every seven days, and measured at ten different body sites every fourteen the day until weaning. The mean live weight of each puppy was measured as 776 g in the 1st week, 1750 g in the 4th week and 2614 g in the 8th week. The survival rate for the puppies was calculated at 95.2% and 83%, respectively at the end of the 4th and 8th week. Some of the body measurements of the puppies at the age when they were removed from suckling (52nd day) such as head length, head girth, body length, shoulder height, ear length, chest girth, rump height, front wrist girth, tail length and back wrist girth were found to be 14.76, 24.03, 22.97, 25.16, 5.93, 30.64, 24.16, 6.62, 15.51 and 5.99 cm, respectively.
Article
In dog breeding permission for breeding is only given when the body measurements of the dog are within the lower and upper limits which are defined in the breed standard. Therefore, the objective of this study was to analyse the systematic and genetic effects on body weight and body measurements recorded at licensing in German shepherd dogs (GSD) over a period of 10 years. The data included withers and chest height, chest circumference and body weight from 36,028 breeding dogs born between 1992 and 2003. Birth year, month of birth and region were significant for the traits analysed. Age at breeding approval was significant for the body measurements withers height and chest height and only significant for male dogs for chest circumference. Inbreeding coefficient was significant as a nonlinear covariate for withers and chest height. The genetic parameters were estimated in linear animal models using residual maximum likelihood (REML) and the relationship matrix of 53,429 dogs. Uni- and bivariate analyses were performed for both sexes together and separately for males and females. Heritability estimates for both sexes together were 0.41 +/- 0.01 for withers height and 0.27 +/- 0.01 for body weight. For the other traits studied, heritability estimates were lower with values of 0.20 +/- 0.01 for chest height and 0.13 +/- 0.01 for chest circumference. In the separate analyses for male and female dogs, heritability estimates were higher for females. Additive genetic correlations were at 0.91 to 0.98 between corresponding traits in males and females. The high genetic correlations indicate that selection for conformation traits equally affects both sexes and does not increase sexual dimorphism in dogs.
Article
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p>Hanoverian, Brazilian Showjumper, English Thoroughbred and Crossbred horses reared by the Brazilian Army were weighed and measured from six months of age to adult. In total 4,860 measurements on 1,445 horses were available. General curves were estimated as a function of time by the Gompertz, Brody, Logistic, Weibull and Richards curves, using PROC NLIN procedures of SAS ®. The Richards Curve did not converge for weight or height of any of the genetic groups or sexes. The logistic curve did not converge for any of the weight traits while the Gompertz also did not converge for height in several groups. R2 varied between 0.55 for weight in females of the crossbred group to 0.92 for males of the same group. For the height traits the highest R2 (0.66) was found for female Hanovarian horses and lowest for males of the same breed (0.12). In general the curves estimated similar values for asymptotic height and weight, except for Logistic curve, which also showed lowest R2 and highest error. Results for the Weibull and Brody curves were similar in all cases so where possible the Brody curve was selected as the best curve as it had less parameters. The Gompertz curve tended to underestimate mature weights and height. Estimates for both weight and height were in general higher in males than for females. In most cases the b parameter was shown to account for < 0.0001% of the variation in the curve shape. The k parameters, which indicate maturity, were of similar magnitude for the Brody, Gompertz and Weibull curves, for both height and weight within breed. This parameter indicated that there is little difference in maturation rates between males and females. KEY WORDS: Brody, Gompertz, Logistic, Richards, Weibull. Cavalos das raças Hanoveriana (HA), Brasileiro de Hipismo (BH), Puro Sangue Inglês (PSI) e mestiços (PSIxBH) criados pelo Exército brasileiro foram pesados e medidos de seis meses de idade até adulto. Realizaram-se 4.860 medidas em 1.445 cavalos. Estimaram-se curvas de crescimento gerais usando os modelos de Gompertz, Brody, Logistic, Weibull e Richards, segundo o procedimento PROC NLIN do programa SAS ®. A curva de Richards não convergiu para peso nem altura para nenhum dos grupos ou sexos avaliados. A curva logística não convergiu para os pesos, enquanto o modelo de Gompertz não convergiu para altura em vários grupos. R2 variou entre 0,55 para peso em fêmeas mestiças até 0,92 em machos do mesmo grupo. Para altura, o maior R2 (0,66) foi para machos Hanovarianos e o menor para fêmeas da mesma raça (0,12). Em geral, as várias curvas estimaram a mesma altura e peso adulto, exceto a curva logística, que teve o menor R2 e mais alto erro dentro de cada grupo. Resultados para as curvas de Weibull e Brody foram similares em todos os casos. A curva de Brody foi selecionada como a melhor, porque possui menos parâmetros. A curva de Gompertz teve a tendência de subestimar pesos e alturas adultos. Estimativas para ambos as características foram mais altas em machos que fêmeas. No maior parte dos casos, o parâmetro b levou em consideração menos que 0,0001% da variação em forma da curva. Os parâmetros k, indicando maturidade, foram de magnitude similar para as curvas de Brody, Gompertz e Weibull, para altura e peso dentro de raça, o que indicou pouca diferença entre machos e fêmeas para taxa de maturação entre sexos. PALAVRAS-CHAVES: Brody, Gompertz, Logistic, Richards, Weibull.</p
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Hundewelpen zeigen je nach Rasse und Ernährung unterschiedliche Gewichtszunahmen. Die Fütterung spielt dabei eine zentrale Rolle. In der vorliegenden Arbeit sollte untersucht werden, ob hausgemachte Rationen oder kommerzielle Futtermittel zur Aufzucht verwendet werden. Dafür wurden Züchter und Besitzer von acht verschiedenen Hunderassen (Beagles, Berner Sennenhunde, Cavalier King Charles Spaniels, Deutsche Doggen, Deutsche Schäferhunde, Labrador Retrievers, Papillons/Phalènes und Shelties) zum Thema Welpenfütterung in der Schweiz befragt. Neben der Beantwortung des Fragebogens (Haltung und Fütterung der Welpen) beinhaltete die Teilnahme an der Studie das wöchentliche Wiegen der Tiere sowie das genaue Festhalten der verfütterten Futtermengen. Die Daten wurden mit den Angaben des Puppy Growth Check© und des Diet Check© Programmes verglichen. Im Ganzen nahmen 67 Hundezüchter mit 391 Welpen an der Studie teil. Die Züchter verwendeten fast ausnahmslos Alleinfuttermittel für die Aufzucht der Welpen und verzichteten auf hausgemachte Rationen. Futterzusätze wurden praktisch nicht mehr verwendet. Die Gewichtsentwicklung der Welpen verlief bei den Deutschen Schäferhunden, Labrador Retrievern und Shelties nahezu ideal. Der berechnete tägliche mittlere Energiebedarf (Diet Check©) war unter Beachtung der Wachstumskurven etwas zu hoch angesetzt. In der Praxis würde sich die Körpermasse vieler Tiere mit 80-90% des empfohlenen täglichen mittleren Bedarfs adäquat entwickeln.
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Since its appearing in 1825, the sigmoideal curve proposed by Benjamin Gompertz has been applied in different fields. In animal sciences it is frequently used to describe the individual´s growth. The present work shows a mathematical analysis of the function and the construction of some of the parameters obtained from it.
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Three sigmoidal growth equations were tested for their usefulness in fitting mammalian growth curves. The von Bertalanffy, Gompertz, and logistic equations were fitted to growth data by nonlinear regression techniques. The residual sum of squares and deviations of predicted neonate, weaning, and adult masses from observed values were used as criteria to choose among the models. The von Bertalanffy equation provided the smallest residual sum of squares, while the Gompertz equation fitted equally well by this criterion. The logistic equation overestimated neonate mass and underestimated adult mass, the Gompertz overestimated neonate mass, and the von Bertalanffy overestimated weaning mass. The Gompertz model was chosen to fit a sample of 331 species; growth rate constants, K, for these species are presented. The relationship of K to adult mass was calculated and was found to have a slope similar to that of altricial birds. K-values were found to be comparable to those reported by Case (1978) and consistently higher than those of Millar (1977). Species having differing rates from those reported by Case or Millar were also identified; ground squirrels had faster growth rates and seals had slower growth rates when rate of growth was estimated by the Gompertz equation.
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In an earlier paper (Durbin & Watson, 1950) the authors investigated the problem of testing the error terms of a regression model for serial correlation. Test criteria were put forward, their moments calculated, and bounds to their distribution functions were obtained. In the present paper these bounds are tabulated and their use in practice is described. For cases in which the bounds do not settle the question of significance an approximate method is suggested. Expressions are given for the mean and variance of a test statistic for one- and two-way classifications and polynomial trends, leading to approximate tests for these cases. The procedures described should be capable of application by the practical worker without reference to the earlier paper (hereinafter referred to as Part I).
Canine and Feline Nutrition: A Resource for Companion Animal Professionals
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Small Animal Clinical Nutrition III
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