Genetic characterization of layer germplasm evolved by AICRP on poultry breeding

Breeding value (BV), genetic parameters and additive genetic, and maternal effects were evaluated on growth and production traits utilizing data from eight generations employing animal model in a rural male parent line (PD‐6) chicken at ICAR‐Directorate of Poultry Research, Hyderabad, India. The least squares means (LSM) for body weight (BW) and shank length (SL) up to 6 weeks of age varied significantly (p ≤ .01) among the generations and hatches. BW increased significantly (p ≤ .01) over the generations and decreased with the hatches. Sex also had a significant effect on BW and shank length except for BW at 0 day (BW0). LSM for BW (BW6) and Shank length (SL6) at 6 weeks of age were 598.84 ± 0.79 g and 74.57 ± 0.04 mm, respectively. Males recorded significantly (p ≤ .01) higher BWs and shank length. All the production traits were significantly (p ≤ .01) influenced by the generation effect. The overall LSM for age at sexual maturity (ASM), egg production at 40 weeks (EP40) and egg weight at 40 weeks (EW40) were 164.93 ± 0.23 days, 74.66 ± 0.40 eggs and 54.79 ± 0.08 g, respectively. Model 3 with additive, maternal permanent environmental and residual effects was the appropriate model for BW2, BW4, BW6, SL4 and SL6, whereas Model 4 with maternal effects was the best for BW0. The heritability estimates for BW6 and SL6 were 0.22 ± 0.02 and 0.18 ± 0.02, respectively. Model 1 with additive direct and residual effects was the best appropriate model for all the production traits. The heritability estimates of EP40 and EW40 were 0.16 ± 0.04 and 0.34 ± 0.05, respectively. BW and shank length were highly correlated with significant (p ≤ .05) positive association from different components. The correlation coefficient from direct additive component between egg production and BW40 was negative, while it was positive with less magnitude between egg production and BW20. The egg production and egg weights had a negative association at different ages. BV of SL6, the primary trait of selection, was significant (p ≤ .05) across the generations and increased linearly with an average genetic gain of 1.05 mm per generation. BV of BW6 was also significant (p ≤ .05) and increased linearly as correlated response with an average genetic response of 22.34 g per generation. BV of EP40 showed an increasing trend with a genetic gain of 0.02 eggs per generation. The EW 40 also increased linearly with an average genetic gain of 0.06 g. The average inbreeding coefficient of the population was 0.015. The study concluded that the population was in ideal status with a linearly increasing trend of average BV with negligible inbreeding over the eight generations of selection.

show abstract

Estimation of breeding value, genetic parameters and maternal effects of economic traits in rural male parent line chicken using pedigree relationships in an animal model

Rajkumar

Prince

Haunshi

et al. 2020

J Animal Breeding Genetics

View full text Add to dashboard Cite

show abstract

Analysis of (co) variance components and estimation of breeding value of growth and production traits in Dahlem Red chicken using pedigree relationship in an animal model

et al. 2021

View full text Add to dashboard Cite

Variance and covariance components of growth and production traits were analyzed employing REML animal model to assess the Dahlem Red (PD-3) chicken population for direct additive genetic, maternal effects and to estimate the estimated breeding value (EBV), genetic parameters, genetic trends and rate of inbreeding (ΔF) utilizing seven generation’s data. The generation and hatch had significant (P≤0.01) effect on the body weight at 0 day (BW0), 2 (BW2), 4 (BW4) and 6 weeks (BW6) and shank length at six weeks of age (SL6). The average least squares means (LSM) for BW6 and SL6 were 273.93±0.62 g and 53.97±0.05 mm, respectively. All the production traits were significantly (P≤0.01) influenced by generation and hatch. The average LSM for age at sexual maturity (ASM), egg production up to 40 weeks (EP40) and egg mass up to 40 weeks (EM40) were 168.82±0.25 d, 72.60±0.41 eggs and 4.21±0.07 kg, respectively. Model 5 with additive direct, maternal genetic, maternal permanent environmental and residual variance components was the best for BW0, BW2 and BW4 based on the AIC values obtained in WOMBAT. Model 4 was the best model for BW6, SL6, ASM, EP40 and EM40 with additive direct, maternal permanent environmental and residual variance components. Maternal effects were higher during early age, decreased with age, and remained present until 20 weeks of age. The heritability (h2) estimates were low to moderate in magnitude for all the growth traits and ranged from 0.02±0.03 to 0.19±0.03. The maternal heritability was high at hatch (0.35±0.06), decreased gradually until 4th week (0.02±0.01) and ceased afterwards. The heritabilities of EP40 (0.11±0.03) and EM40 (0.12±0.04) were low. The direct additive genetic correlations (ra) between BW2, BW4, BW6 and SL6 were high and positive (P≤ 0.05). The additive genetic and maternal permanent environmental correlation between EP40 and EM40 were high and positive (P≤ 0.05). The EBV of EM40 was significant (P≤ 0.05) with 0.48 kg/generation in PD-3 chicken at the end of the seventh generation. The EBV of EP40 showed an increasing trend with a genetic gain of 1.87 eggs per generation. The average inbreeding coefficient of the population was 0.019 and average ΔF was 0.007 over the last seven generations of selection. The EBV trends for primary and associated traits showed linear trends in the desired direction and negligible inbreeding.

show abstract

Delineating maternal influence in regulation of variance in major economic traits of White Leghorns: Bayesian insights

Kour,

Chatterjee,

Rajaravindra

et al. 2024

PLoS ONE

View full text Add to dashboard Cite

Proper variance partitioning and estimation of genetic parameters at appropriate time interval is crucial for understanding the dynamics of trait variance and genetic correlations and for deciding the future breeding strategy of the population. This study was conducted on the same premise to estimate genetic parameters of major economic traits in a White Leghorn strain IWH using Bayesian approach and to identify the role of maternal effects in the regulation of trait variance. Three different models incorporating the direct additive effect (Model 1), direct additive and maternal genetic effect (Model 2) and direct additive, maternal genetic and maternal permanent environmental effects (Model 3) were tried to estimate the genetic parameters for body weight traits (birth weight, body weight at 16, 20, 40 and 52 weeks), Age at sexual maturity (ASM), egg production traits (egg production up to 24, 28, 40, 52, 64 and 72 weeks) and egg weight traits (egg weight at 28, 40 and 52 weeks). Model 2 and Model 3 with maternal effects were found to be the best having the highest accuracy for almost all the traits. The direct additive genetic heritability was moderate for ASM, moderate to high for body weight traits and egg weight traits and low to moderate for egg production traits. Though the maternal heritability (h2mat) and permanent environmental effect (c2mpe) was low (<0.1) for most of the traits, they formed an important component of trait variance. Traits like egg weight at 28 weeks (0.14±0.06) and egg production at 72 weeks (0.13±0.07) reported comparatively higher values for c2mpe and h2mat respectively. Additive genetic correlation was high and positive between body weight traits, between egg weight traits, between consecutive egg production traits and between body weight and egg weight traits. However, a negative genetic correlation existed between egg production and egg weight traits, egg production and body weight traits, ASM and early egg production traits. Overall, a moderate positive genetic correlation was estimated between ASM and body weight traits and ASM and egg weight traits. Based on our findings, we can deduce that maternal effects constitute an important source of variation for all the major economic traits in White Leghorn and should be necessarily considered in genetic evaluation programs.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Genetic characterization of layer germplasm evolved by AICRP on poultry breeding

Cited by 4 publications

References 3 publications

Estimation of breeding value, genetic parameters and maternal effects of economic traits in rural male parent line chicken using pedigree relationships in an animal model

Estimation of breeding value, genetic parameters and maternal effects of economic traits in rural male parent line chicken using pedigree relationships in an animal model

Analysis of (co) variance components and estimation of breeding value of growth and production traits in Dahlem Red chicken using pedigree relationship in an animal model

Delineating maternal influence in regulation of variance in major economic traits of White Leghorns: Bayesian insights

Contact Info

Product

Resources

About