Evaluation of animal models to explore the influence of maternal genetic and maternal permanent environment effect on reproductive performance of Jersey crossbred cattle

Abstract

The present study was conducted on 1,002 reproductive records of 430 Jersey crossbred cattle, descended from 57 sires and 198 dams, maintained at the Eastern Regional Station of ICAR‐National Dairy Research Institute, Kalyani, Nadia, West Bengal, India to investigate the influence of direct genetic, maternal genetic and maternal permanent environmental effect on three most important reproductive traits viz., number of service per conception (NSPC), days open (DO) and calving interval (CI) of Jersey crossbred cattle. Six single‐trait animal models (including or excluding maternal genetic or permanent environmental effects) were fitted to analyse these traits, and the best model was chosen after testing the significant increase in the log‐likelihood values when additional parameters were added in the model. Direct heritability estimates for NSPC, DO and CI from the best model were 0.10, 0.14 and 0.20, respectively. The maternal permanent environmental (c2) effects on reproductive traits accounted for almost negligible fraction of the total phenotypic variance in this study. The maternal genetic effects (m2) also contributed very little (0%–3%) to the total phenotypic variance except for CI where it was important and accounted for 20% of phenotypic variance. A significantly large negative genetic correlation was observed between direct and maternal genetic effects for all traits, suggesting the presence of antagonistic relationship between dam's direct additive component and daughter's additive genetic component. Results suggest that both direct and maternal effects were important only for CI but not for other traits. Therefore, both direct additive effects and maternal genetic effect need to be considered for improving this trait by selection.

Estimation of direct and maternal covariance along with genetic and phenotypic trends of reproduction traits in Murrah buffalo

“…Comparing our findings with the breadth of existing research, Kumar and Mandal's (2021) study on Jersey crossbred cows reported a higher heritability ranging from 0.14 to 0.20 and a similar maternal effect ( m 2 = 0.00 to 0.02), emphasizing the shared genetic influences but with higher heritability in their study. In contrast, Kumar et al.…”

“…Comparing our findings with the breadth of existing research, Kumar and Mandal's (2021) study on Jersey crossbred cows reported a higher heritability ranging from 0.14 to 0.20 and a similar maternal effect (m 2 = 0.00 to 0.02), emphasizing the shared genetic influences but with higher heritability in their study. In contrast, Kumar et al (2016) illustrated a wider range of heritability (0.04 to 0.10) and maternal effects (0.06 to 0.09), highlighting the diverse genetic nature of SP across different cattle populations.…”

“…Abu El‐Naser (2020) conducted a study on Egyptian buffaloes, reporting a lower additive genetic variance ($$$ {\sigma}_{\mathrm{a}}^2 $$$ = 465.45) but a higher heritability ( h 2 = 0.19) compared with our findings. Kumar and Mandal (2021) in Jersey crossbred cattle observed higher values for both additive genetic variance ($$$ {\sigma}_{\mathrm{a}}^2 $$$ = 2340.744 to 3835.815) and heritability ( h 2 = 0.16 to 0.25), emphasizing breed‐specific variations. Van Gioi et al.…”

“…Abu El-Naser (2020) conducted a study on Egyptian buffaloes, reporting a lower additive genetic variance ( 2 a = 465.45) but a higher heritability (h 2 = 0.19) compared with our findings. Kumar and Mandal (2021) ( 2 a = 5107.8 to 5168.8) but comparable heritability (h 2 = 0.08 to 0.12) and genetic correlation (r am = −0.66). Cassiano et al (2004) in Murrah buffalo and Patil et al (2018) in Murrah buffalo reported heritability values (h 2 = 0.04 to 0.05 and h 2 = 0.08 ± 0.14, respectively) similar to our study.…”