Genetic relationship of litter traits between farrowing and weaning in Landrace and Large White pigs

Abstract

We estimated genetic parameters in Landrace and Large White pig populations for litter traits at farrowing (total number born, number born alive, number stillborn, total litter weight at birth (LWB), and mean litter weight at birth) and those at weaning (litter size at weaning (LSW), total litter weight at weaning (LWW), mean litter weight at weaning (MWW), and survival rate from farrowing to weaning). We analyzed 65,579 records at farrowing and 6,306 at weaning for Landrace, and 52,557 and 5,360, respectively, for Large White. Single‐trait and two‐trait repeatability animal models were exploited to estimate heritability and genetic correlation respectively. Heritability estimates of LSW were 0.09 for Landrace and 0.08 for Large White. Genetic correlations of LSW with MWW were –0.43 for Landrace and –0.24 for Large White. Genetic correlations of LSW with LWW and LWB ranged from 0.5 to 0.6. The genetic correlation of MWW with LWW was positive, but that with LWB was negligible. The results indicate that utilizing LWW or LWB could improve LSW efficiently, despite the antagonistic genetic correlation between LSW and MWW.

Relationship between litter size at birth and within‐litter birth weight characteristics in laboratory mice as pilot animal for pig

“…The estimated genetic correlation between LWB and MWB was weakly positive (Table 5). Previous studies estimated positive but different values from 0.185 to 0.87 (Gutiérrez et al., 2006; Hermesch et al., 2000; Ogawa et al., 2019a; Wolf et al., 2008), which might be at least partly because MWB was defined as a ratio to LWB (e.g., Gunsett, 1987; Iwaisaki & Wilton, 1993; Ogawa et al., 2019c). The estimated genetic correlation of LWB was negligible with MinIWB, but moderately to highly positive with Range and SDIWB and moderately negative with Skew.…”

“…(e.g., Gunsett, 1987;Iwaisaki & Wilton, 1993;Ogawa et al, 2019c). Sutherland (1965) derived the formula to obtain the approximate genetic correlation between a ratio-defined trait and its denominator by modifying the formula by Pearson (1897).…”

An attempt of using public ambient temperature data in swine genetic evaluation for litter size traits at birth in Japan

“…(2019c) reported the estimated effects of farrowing season for NBA in Landrace and Large White dams raised on multiple farms in different prefectures of a single Japanese pig breeding company. Ogawa et al . (2019c) showed lower estimated values for winter than for spring, although the difference between the values was 0.30 in Landrace and 0.21 in Large White, both smaller than this study.…”

“…Japanese pig farms are widely distributed in Japan (e.g., Koike et al . 2018; Ogawa et al . 2019c; Fujimoto et al .…”

“…Japan is an island country that has four distinct seasons with a climate ranging from subarctic in the north to subtropical in the south, and the conditions are different between the Pacific side and the Sea of Japan side (https://www.data.jma.go.jp/gmd/cpd/longfcst/en/tourist.html). Japanese pig farms are widely distributed in Japan (e.g., Koike et al 2018;Ogawa et al 2019c;Fujimoto et al 2021).…”