Reproduction

Evaluating service sire effects on genetic parameter estimation for reproductive and maternal traits in Duroc, Landrace and Yorkshire pig populations

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Abstract

Abstract Text:Most reproductive and maternal traits in pigs are considered to have low heritability. For these traits, integrating available information into genetic evaluation models could improve the accuracy of estimated breeding values. In addition to the sow genetic and non-genetic effects, the service sire is considered to influence the reproductive performance. In this study, we aimed to estimate the genetic parameters of a comprehensive set of reproductive and maternal traits, including total number born(TNB), number born alive (NBA), total number weaned (TNW), number of stillborn piglets (STB), and number of mummified piglets (MUM), and to quantify the contribution of the service sire effect to the phenotypic and genetic variability of these traits in commercial pigs. The dataset was provided by Fujian Yongcheng Breeding Technology Group Corporation (Fuqing, Fujian Province, China) collected in from three farms, consisting of 5,883 Duroc, 7,556 Landrace, and 11,363 Large White dams that have 543, 471, and 617 service sires, respectively. Genetic analyses were performed using the BLUPF90+ software. Two repeatability animal models were fitted for each trait, including a base model containing additive genetic and permanent environmental effects, and an extended model that additionally included the service sire effect. The fixed effects of contemporary group, parity, and age at first farrowing were included in all models, with the number of piglets after cross-fostering added as an additional fixed effect for TNW. Model comparisons based on the Akaike Information Criterion (AIC) and likelihood ratio tests (LRT) indicated that inclusion of the service sire effect consistently improved model fit for most traits. Estimated heritabilities ranged from 0.085 to 0.124 for NBA, 0.100 to 0.128 for TNB, 0.012 to 0.035 for TNW, 0.051 to 0.062 for STB, and 0.014 to 0.027 for MUM. The proportion of phenotypic variance attributable to the service sire effect ranged from 0.32% to 5.53% in Duroc, 0.26% to 0.93% in Landrace, and 0.19% to 4.00% in Yorkshire. The inclusion of the service sire effect had minimal impact on genetic parameter estimates, which remained highly similar across models. However, it consistently reduced AIC values and yielded significant LRT results, suggesting that the extended model captured additional sources of variation that were previously ignored. Therefore, despite its relatively small contribution to phenotypic variance, the service sire effect significantly improved model fit and should be considered when modeling lowly heritable reproductive and maternal traits in commercial Duroc, Landrace, and Yorkshire pig populations.

Keywords: 2026

How to Cite:

Tang, H., Mulim, H., Chen, S., Xue, H., Qiu, D., Liu, Y., Schinckel, A. & Oliveira, H., (2026) “Evaluating service sire effects on genetic parameter estimation for reproductive and maternal traits in Duroc, Landrace and Yorkshire pig populations”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286174. doi: https://doi.org/10.31274/wcgalp.23868

Rights: 1