Exploring the non-genetic factors that affect reproductive traits of Saanen goats in Indonesia

Adjustment of trait records for different non-genetic factors increases the accuracy of genetic parameters and enables more accurate selection. This study aimed to investigate the non-genetic factors affecting reproductive traits in Saanen goats at the Baturraden breeding centre, Indonesia. The data of 71 Saanen does from the years 2014 to 2021 consisted of reproductive traits, namely, total birth weight (TBW), age at first kidding (AFK), kidding interval (KI), litter size (LS), multiple birth rate (MBR) and kidding failure rate (KFR). Non-genetic factors explored included parity, season of kidding (SK), and year of kidding (YK). The data was analysed using STATISTICA statistical package version 8.0. First, the descriptive statistics of reproductive traits were analysed; second, the effect of non-genetic factors on reproductive traits was analysed using one-way ANOVA. The mean ± SE values for the descriptive analysis were LS (1.28±0.41), TBW (6.35±0.24 kg), KI (9.46±0.28 months), AFK (15.63±0.64 months), MBR (29%) and KFR (17%). The one-way ANOVA results indicated significant effects of parity (p<0.05) on TBW and LS, while SK had a significant effect on AFK (p<0.0001), and YK had significant effects on TBW, AFK (p<0.0001), and LS (p<0.001). The TBW, LS and MBR increased as parity advanced, while KI declined with parity. The AFK was higher in dry season (19.3±3.58 months) than in wet season (13.3±3.05 months). Therefore, the study concluded that non-genetic factors have a significant effect on reproductive traits. Adjusting reproductive traits for significant non-genetic factors increases the accuracy of estimated genetic parameters and selection programs for these traits in Saanen goats.