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Non-additive genetic effects are important to increase the accuracy of estimating genetic parameters for growth traits. The aim of this study was to estimate genetic parameters and variance components, specially dominance and epistasis genetic effects, for growth traits (birth weight (BW), weaning weight (WW), 3 (W3), 6 (W6), 9 (W9), and 12 (W12) month weight) in Adani goats. Analyses were carried out using Bayesian method via Gibbs sampler animal model by fitting of 18 different models. All fixed effects (sex, type of birth, age of dam, and year) showed significant effects on BW, WW, W3, and W6, whereas the type of birth and age of dam were not significant on W9 and W12. With the best model, direct heritability estimates were 0.347, 0.178, 0.158, 0.359, 0.278, and 0.281 for BW, WW, W3, W6, W9, and W12 traits, respectively. Maternal permanent environmental effect was significant for BW and WW, but maternal genetic effect was significant only for W3. Dominance and epitasis effects were significant almost for all traits and as a proportion of phenotypic variance were ranged from 0.115 to 0.258 and 0.107 to 0.218, respectively. The range of accuracy of breeding values estimated for growth traits with appropriate evaluation models was from 0.521 to 0.652, 0.616 to 0.694, and 0.548 to 0.684 for the all animals, 10% of the best males and 50% of the best females, respectively. When dominance and epistasis effects added to models, the error variance was reduced and the accuracy of estimated breeding values increased. The accuracy of the best model showed a significant difference with the accuracy of other models (p < 0.01). The result of the present study suggests that non-additive genetic effects should be in genetic evaluation models for goat growth traits because of its effect on accuracy of estimated breeding values. [ABSTRACT FROM AUTHOR]

• Dominance and epistasis effects are important for the average daily gain traits and could be added to evaluation models. • Adding the non-additive genetic effects to models led to increase the accuracy of estimated breeding values. • The adgbww3 and adgbww6 traits can be the basis of selection for the next generation. Considering the dominance and epistasis effects in the analysis can increase the accuracy of estimating breeding values. The objective of this study was to fit the best model for each average daily gain trait (average daily gain from birth to weaning (adgbwww., from birth to 3 months (adgbww3), from birth to 6 months (adgbww6), from weaning to 3 months (adgwww.), from 3 to 6 months (adgw3w6), from 6 to 9 months (adgw6w9), and from 9 to 12 months (adgw9w12)) and the estimation of the genetic parameters and variance components, especially non-additive genetic effects, in Adani goats. Analyses were carried out using the Bayesian method via the Gibbs sampler animal model by fitting 18 different models. With the best model, direct heritability estimates were 0.093, 0.250, 0.256, 0.084, 0.036, 0.048, and 0.151 for adgbwww. adgbww3, adgbww6, adgwww., adgw3w6, adgw6w9 and adgw9w12 traits, respectively. Maternal genetic and maternal permanent environmental effects were significant only for adgbwww.trait. Dominance and epistasis effects were significant almost for all traits and as a proportion of phenotypic variance was the range from 0.068 to 0.221 and 0.106 to 0.237, respectively. Adding dominance and epistasis effects to models reduced the error variance and the accuracy of estimating breeding values was increased. The accuracy of breeding values of these traits with the best models ranged from 0.456 to 0.674, 0.493 to 0.656, and 0.424 to 0.674 for all animals, 10 % of best males and 50 % of the best females, respectively. The result of the present study suggests that dominance and epistasis effect was important for average daily gain traits of Adani goats and should be included in evaluation models. [ABSTRACT FROM AUTHOR]

• In the present study, survival analysis was performed using of time-dependent variable and censored data via gibbs sampling method. • The non-genetic effects had a significant effect on lamb survival from birth to the last recording date. • Estimated direct heritability for survival ranged 0.097 to 0.157. The contribution of maternal permanent environmental variance ratio was estimated higher than maternal heritability. • Improvement of survival for Sangsari breed could be possible through management practice as well as genetic selection. The aim of this study was to investigate the genetic and non-genetic effects on survival traits of Sangsari sheep from birth to the last recording date. Data base with 35,470 sheep survival records was collected during 1988 to 2010 in 11 flocks by the Animal Breeding Center of Iran. The non-genetic effects were evaluated on hazard rate of sheep in different times with survival and cmprsk packages. Exponential distribution based on censored data was used to estimate the genetic parameters of the survival from birth to the last recording date. The linear animal models were fitted using Bayesian method via Gibbs sampling of the MCMCglmm package. The overall mortality rate for Sangsari lambs was 2.00 and 25.72% for birth to 100 and 500 day of age, respectively, and its value increased upto 90.54% till 3400 day of age. The results indicated that the year and month of birth, sex of lamb, birth weight, age of ewe, flock (P < 0.001), and type of birth (P < 0.01) had a significant effect on sheep survival. Estimated direct heritability for survival from birth to the last recording date by different linear models ranged 0.097 to 0.157. The contribution of maternal permanent environmental variance ratio was estimated higher than maternal heritability, thus this effect must be considered in the evaluation models for improving sheep survival. The present findings suggest that sheep survival improvement could be possible through management practice as well as genetic selection. [ABSTRACT FROM AUTHOR]

Highlights • Humoral immune responses in Japanese quail are heritable. • After immunization of the birds with SRBC, genetic correlations between immunoglobulin M (IgM) and early growth traits are positive, but for AbT and IgY are negative. • Genetic correlations for AbNDV with BW traits are negative, but with BWG traits are positive. • Genetic selection for IgM responses could improve growth traits. Abstract The aim of this study was to estimate genetic parameters of early growth performances and humoral immune responses (antibody titers against sheep red blood cells (SRBC) and Newcastle Disease Virus (NDV)) in Japanese quail. For this purpose, a total of 10,923 records of early growth traits including body weights (BW) at 0, 5, 10, 15 and 20 d old and body weight gain (BWG) between 0–5, 5–10, 10–15 and 15–20 days, and 2,314 records of humoral immune responses were used to estimate genetic parameters through multiple-trait Bayesian analyses. The estimates of heritability of BW and BWG traits were 0.14 to 0.28 and 0.08 to 0.10, respectively. The range of genetic and phenotypic correlations for BW traits varied from 0.63 to 0.98 and 0.17 to 0.89, respectively. Furthermore, estimates of genetic and phenotypic correlations for BWG traits at different ages were in the range of 0.46 to 0.86 and 0.12 to 0.46, respectively. Heritability estimates of total antibody titer (AbT), titer of immunoglobulin Y (IgY) and titer of immunoglobulin M (IgM) against SRBC were 0.21, 0.24 and 0.20, respectively, but h2 of antibody titer against NDV (AbNDV) was lower than those of estimated for SRBC antigen (h2 = 0.17). Genetic correlations between antibody titers against SRBC and NDV were similar (0.42 − 0.46). Genetic correlations were positive only for IgM with BW traits, however, estimates of genetic correlation between BW traits at different ages with AbT and IgY were negative and moderate (−0.30 to −0.66), and with AbNDV were negative and low (−0.13 to −0.25). Like BW traits, genetic and phenotypic correlations between AbT and IgY titers and BWG traits were negative and varied from −0.21 to −0.72, while genetic correlations of BWG traits with IgM and AbNDV titers were both positive (0.11 to 0.27 and 0.23 to 0.31, respectively). It is suggests that selection to improved BW and BWG traits may lead to decline of humoral immune responses in Japanese quail. However, improvement of BW and BWG traits and humoral immune responses would be possible through selection for IgM titers against SRBC due to its high and positive genetic correlation with growth traits. [ABSTRACT FROM AUTHOR]

Early growth traits in quails are considered as the growth performances before the inflection point which are genetically different from body weights (BW) at later stages. Moreover, in addition to growth performance, humoral immunity is moderately heritable and is considered in some breeding programs. However, estimating the direct genetic, particularly the maternal genetic correlations between growth and immunity in quail, are not studied sufficiently, which were the aims of the present study. The quails' BW were recorded at hatch (BW0) to 25 d of age with a 5-d interval and body weight gains (BWG) were measured as average growth performance of the birds in a 5-d period. Antibody titer against Newcastle disease virus (IgN) was measured through the hemagglutination inhibition (HI) test. For titration of anti-SRBC antibodies (IgY and IgM), a hemagglutination microtiter assay was used. In general, growth records in 4,181 birds and humoral immune responses in 1,023 birds were assigned to the study. The genetic parameters were estimated by single-trait analysis via Gibb's sampling. After finding the best model for each trait, multi-trait analysis was done to estimate the direct and maternal genetic correlations. Direct heritabilities (h2) were estimated to be moderate for BW (0.481−0.551) and BWG (0.524−0.557), while h2 for immune responses were low (0.035−0.079). Maternal environmental effect (c2) was only significant for BW0, BW5, and BWG0-5. Maternal heritabilities (m2) for BW and BWG were all lower than corresponding h2, ranging from 0.072 (BW25) to 0.098 (BW0). The m2 for IgN (0.098) was more than 2.5 times greater than h2 (0.040) for this trait. Direct (r a) and maternal (r m) genetic correlations between IgN-BW, IgY-BW, and IgY-BWG were negative, while ra and rm for IgM-BW, IgN-BWG, and IgM-BWG were positive. The r a between humoral immune responses were low to moderate and rm was significant only for IgY-IgM (0.339). Given positive genetic correlations in BWG-IgN and BWG-IgM as well as positive genetic correlations between both IgN and IgM with IgY, it is suggested that including the BWG in the breeding programs would directly result in the improvement of the birds' growth performance. It would also contribute indirectly to the improvement of the birds' humoral immune responses. [ABSTRACT FROM AUTHOR]