Parity changed fecal microbiota of sows and its correlation with milk long-chain fatty acid profiles

The goal of this study was to characterize the fecal microbiota profiles of gestating sows, along with the fecal microbiota and milk fatty acid contents of lactating sows and their correlations with reproductive performance at different parities. The results showed that the microbiota of third parity gestating sows contained a greater abundance of Prevotella compared to the other two parity groups, while lactating sows exhibiting higher reproductive performance at fifth parity exhibited a greater abundance of Lactobacillus species. The lactating sows with higher reproductive performance also exhibited higher total monounsaturated fatty acid (MUFA) and higher total polyunsaturated fatty acid (PUFA) levels relative to sows with lower reproductive performance at all three analyzed parities, especially sows at fifth parity produced the lowest total saturated fatty acid (SFA) levels, and showed the highest C18:1n9c and C18:2n6c concentrations. In correlational analyses, the abundance of Oligella, Lactobacillus, and Corynebacterium was highly positively correlated with C18:1n9c, C18:2n6c, and C20:4n6. Overall, these results provide a rational basis for efforts to improve sow reproductive performance through the provision of precisely regulated nutrition. KEY POINTS: • Clear differences in the fecal microbiota were evident between sows of different parities. • Lactating sows with high reproductive performance showed distinct milk fatty acid profiles.

Relationship between Body Weight of Primiparous Sows during Late Gestation and Subsequent Reproductive Efficiency over Six Parities

The present study investigated the impact of parity 1 gilt body weight during late gestation (d 109) on subsequent reproductive performance of sows and performance of suckling pigs. A total of 2,404 farrowing records over 6 parities were divided into six groups on the basis of body weight (190, 200, 210, 220, 230, and 240 kg) at d 109 of gestation of 585 gilts. Significant effects (p< 0.05) of body weight on sow retention rate was noticed, with the 210 kg group having the lowest culling rate and highest total number of piglets born alive over the 6 parities. With increase of body weight, a linear increase (p<0.05) in losses of body weight and backfat during the lactation period of parity 1 and a linear decrease (p<0.05) in backfat loss for parities 4 and 6 were found. Compared with light sows, heavy sows had higher (p<0.05) litter weight at birth for parities 1 and 2 and at weaning in parity 1. Sow weaning-to-estrus interval of sows was not influenced (p>0.05) by body weight. In conclusion, maintaining optimal body weight during gestation would be beneficial to sows and suckling piglets.