Adaptation Physiology Group, Wageningen Institute of Animal Sciences (WIAS), Wageningen University, 6700 AH Wageningen, The Netherlands.
Anim Reprod Sci. 2010 Oct;122(1-2):82-9. doi: 10.1016/j.anireprosci.2010.07.009. Epub 2010 Jul 30.
An impaired reproductive performance in second parity compared to first parity sows, decreases reproductive efficiency and, perhaps, longevity of sows. This study aims to quantify the effect of live weight development and reproduction in first parity on reproductive performance of second parity sows, i.e. pregnancy rate as well as litter size. Measures of sow development (live weight at first insemination, farrowing and weaning) and reproduction (total number of piglets born, weaning to insemination interval, lactation period, number piglets weaned) were recorded on two experimental farms. Logistic regression analysis was done for the binary outcome 'non-pregnancy from first insemination after first weaning' (yes/no). General linear regression analysis was used for litter size from 1st insemination in second parity. Repeat breeders were omitted from the analysis on litter size in second parity, since a prolonged period between weaning and conception can positively influence litter size. Farms differed significantly in measures of sow live weight development and therefore data were analyzed per farm. Compared with gilts from farm A, gilts from farm B were older and heavier at: first insemination (275±0.9 days and 145±0.8kg for farm B vs. 230±0.6 days and 124±0.5kg for farm A), first farrowing (resp. 189±1.1 vs. 181±0.9kg) and first weaning (resp. 165±1.1 vs. 156±0.9kg). Weight loss during pregnancy was similar for both farms (resp. 24.9±0.7 and 23.7±1.0kg). Gilts from farm A, however, gained more weight in the period between first insemination and first weaning compared with gilts from farm B (resp. 36.1±0.8 and 20.9±1.3kg). Non-pregnancy in second parity was 11% for farm A and 15% for farm B. Litter sizes in first and second parity were, respectively, 10.7±0.1 and 11.6±0.2 for farm A and 11.8±0.1 and 11.6±0.1 for farm B. Variables associated with non-pregnancy and litter size in second parity differed between farms. On farm A, mainly sow live weight development was associated with non-pregnancy and litter size in second parity, whilst on farm B variables like total number born in 1st parity and sow line, were associated with non-pregnancy and litter size in second parity. On both farms, higher weight gain from first insemination to first weaning was associated with a decrease in non-pregnancy (odds ratio 0.7 per 10kg for farm A and 0.8 per 10kg for farm B) and on farm A with higher litter size in second parity (β=0.42 per 10kg weight gain). Results show that sow live weight development affects reproductive performance in second parity, especially on farm A where gilts are relatively light or young at first insemination. Management of these animals should aim to optimize development at first insemination and to increase growth between first insemination and first weaning in order to optimize production in second parity.
经产母猪与初产母猪相比，第二胎的繁殖性能下降，降低了繁殖效率，甚至可能降低母猪的使用寿命。本研究旨在量化第一胎产仔数和繁殖对第二胎产仔数的影响，即妊娠率和窝产仔数。在两个实验农场记录了母猪的生长（第一次配种时的体重、分娩和断奶时的体重）和繁殖（出生的总仔猪数、断奶至配种间隔、哺乳期、断奶仔猪数）指标。对第一次断奶后第一次配种的“非妊娠”（是/否）进行二项式回归分析。对于第二胎的窝产仔数，使用一般线性回归分析。由于断奶和配种之间的延长时间可以积极影响窝产仔数，因此在第二胎的窝产仔数分析中排除了重复配种母猪。农场在母猪活体重发育方面存在显著差异，因此按农场进行数据分析。与来自农场 A 的母猪相比，来自农场 B 的母猪在以下方面更年长、体重更大：第一次配种（275±0.9 天和 145±0.8kg 用于农场 B，而 230±0.6 天和 124±0.5kg 用于农场 A），第一次分娩（分别为 189±1.1 和 181±0.9kg）和第一次断奶（分别为 165±1.1 和 156±0.9kg）。两个农场的妊娠期体重损失相似（分别为 24.9±0.7 和 23.7±1.0kg）。然而，与来自农场 B 的母猪相比，来自农场 A 的母猪在第一次配种和第一次断奶之间增加了更多的体重（分别为 36.1±0.8 和 20.9±1.3kg）。农场 A 的第二胎非妊娠率为 11%，农场 B 的第二胎非妊娠率为 15%。第一胎和第二胎的窝产仔数分别为农场 A 的 10.7±0.1 和 11.6±0.2，农场 B 的 11.8±0.1 和 11.6±0.1。与第二胎产仔数相关的非妊娠和第二胎产仔数的变量在农场之间有所不同。在农场 A 中，主要是母猪的活体重发育与第二胎的非妊娠和窝产仔数有关，而在农场 B 中，总产仔数和母猪系等变量与第二胎的非妊娠和窝产仔数有关。在两个农场中，从第一次配种到第一次断奶的体重增加与非妊娠的减少有关（农场 A 的每增加 10kg 的比值比为 0.7，农场 B 的比值比为 0.8），并且在农场 A 中，第二胎的窝产仔数增加（每增加 10kg 的体重增加为 0.42）。结果表明，母猪活体重发育影响第二胎的繁殖性能，特别是在农场 A 中，母猪第一次配种时体重较轻或较年轻。这些动物的管理应旨在优化第一次配种时的生长发育，并增加第一次配种和第一次断奶之间的生长，以优化第二胎的生产。
