School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia.
School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia; Robinson Research Institute, The University of Adelaide, SA 5005, Australia.
Anim Reprod Sci. 2024 Apr;263:107440. doi: 10.1016/j.anireprosci.2024.107440. Epub 2024 Feb 21.
Increasing piglet weaning age while maintaining the reproductive efficiency of the breeding herd depends on the ability to stimulate sows to ovulate during lactation without reducing subsequent pregnancy rates and litter sizes. The aim of this study was to determine if a reduction in piglet suckling load, either prior to or immediately after mating in lactation, altered ovarian follicle development and increased embryo survival to day 30 of gestation. Fifty-nine multiparous Large White x Landrace sows were allocated to one of three treatments; litter size maintained at 11 piglets (control); litter size reduced to seven piglets on day 18 of lactation (split wean (SW)); or litter size reduced to seven piglets at expression of lactation oestrus (oestrus split wean (OES SW)). The percentage of sows that expressed lactation oestrus did not differ between treatments (79.7 %; P > 0.05) and split weaning had minimal effects on ovarian follicle development. Pregnancy rates were higher for SW and OES SW sows, compared to control sows. Embryo survival to day 30 of gestation was higher for SW sows (73.7 %) compared with control (56.4 %) and OES SW sows (49.5 %; P < 0.05). In summary, weaning a portion of the litter prior to mating in lactation improved pregnancy rates and embryo survival.
在保持繁殖群繁殖效率的同时增加仔猪断奶日龄，取决于能否在哺乳期刺激母猪排卵，而不降低随后的妊娠率和窝产仔数。本研究旨在确定在哺乳期配种前或配种后立即减少仔猪的吮乳负荷是否会改变卵巢卵泡的发育，并增加胚胎存活至妊娠 30 天。将 59 头经产长白×大约克母猪分配到以下三种处理之一：维持 11 头仔猪的窝产仔数（对照）；哺乳期第 18 天减少至 7 头仔猪（分批断奶（SW））；或在哺乳期发情时减少至 7 头仔猪（发情分批断奶（OES SW））。发情母猪的比例在处理间没有差异（79.7%；P>0.05），且分批断奶对卵巢卵泡发育的影响很小。与对照组母猪相比，SW 和 OES SW 母猪的妊娠率更高。胚胎存活至妊娠 30 天的比例在 SW 母猪中更高（73.7%），而对照组（56.4%）和 OES SW 母猪（49.5%；P<0.05）。总之，在哺乳期配种前断奶一部分仔猪可提高妊娠率和胚胎存活率。
