Pig Development Department, Animal & Grassland Research & Innovation Centre, Teagasc Moorepark, Fermoy, Co Cork P61 P302, Ireland; Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Department of Animal Behaviour, ul. Postępu 36A, Jastrzębiec 05-552 Magdalenka, Poland.
Pig Development Department, Animal & Grassland Research & Innovation Centre, Teagasc Moorepark, Fermoy, Co Cork P61 P302, Ireland.
Animal. 2021 Mar;15(3):100158. doi: 10.1016/j.animal.2020.100158. Epub 2021 Jan 7.
Aggression resulting from mixing to establish a dominance hierarchy is a major welfare concern for group-housed sows. The associated stress can negatively impact aspects of reproductive performance. Objectives of this study were to investigate associations between 1) age at first service (AFS) and mixing aggression intensity in first parity sows, 2) mixing aggression intensity and reproductive performance within and between parity one and parity two, and 3) mixing aggression intensity, floor type during gestation and reproductive performance. Gilts (n =160, hereafter referred to as sows) were mixed into stable groups of eight unfamiliar individuals approximately 4 days after artificial insemination, housed on fully slatted concrete (CON; n =80) floor uncovered or covered with rubber slat mats (RUB; n =80), and followed through two parities. Skin lesions (SLMIX; a proxy for the intensity of mixing aggression), were scored post mixing in each parity according to severity (0=no lesions to 5=severe lesions) on five body regions (ear, neck, hindquarter, rump, and belly) on the left and right sides, and at the tail/anogenital region. Total SLMIX score was calculated for each sow. Data on reproductive performance traits were acquired retrospectively from farm records for both parities. Two analyses were performed: 1) data from each parity were analysed separately and 2) SLMIX score in parity one was used to predict reproductive performance in parity two. Lower AFS was associated with a lower SLMIX score in parity one (P =0.031). There was no association between SLMIX score and reproductive performance in parity one, while sows with higher SLMIX score in parity two had a higher proportion of piglets dead during lactation (P =0.027) and a longer cycle length (P =0.003) in parity two. Sows with higher SLMIX scores in parity one had more non-productive days (P <0.001) in parity two. Concrete sows had a higher SLMIX score than RUB sows in parity one (P =0.015), but not in parity two. In addition, CON sows had a higher proportion of piglets born dead (P =0.013) compared with RUB sows in parity two. Mixing aggression has a negative influence on reproductive performance within parities, and it may also have a long-term negative carry-over effect on reproductive performance in subsequent parities. Serving gilts at younger ages could help to minimize the intensity of aggression at mixing, while housing on rubber flooring has beneficial implications for their reproductive performance.
由于建立优势等级制度而导致的攻击性是群体饲养母猪的一个主要福利问题。相关压力会对繁殖性能产生负面影响。本研究的目的是：1）调查初产母猪的首次配种年龄（AFS）与混合攻击强度之间的关系；2）混合攻击强度与第一胎和第二胎之间的繁殖性能之间的关系；3）混合攻击强度、妊娠期间的地板类型与繁殖性能之间的关系。后备母猪（n=160，以下简称母猪）在人工授精后大约 4 天被混合到 8 个不熟悉的个体的稳定群体中，饲养在完全有缝隙的混凝土（CON）地板上，未覆盖或覆盖有橡胶格栅垫（RUB）（n=80），并通过两胎进行跟踪。根据严重程度（0=无损伤到 5=严重损伤），在每胎的每个混合后对五个身体部位（耳朵、颈部、后躯、臀部和腹部）的左侧和右侧以及尾巴/肛门区域对皮肤损伤（SLMIX；混合攻击强度的代表）进行评分。为每头母猪计算总 SLMIX 评分。两胎的繁殖性能数据均从农场记录中回溯获得。进行了两项分析：1）分别对每一胎的数据进行分析；2）将第一胎的 SLMIX 评分用于预测第二胎的繁殖性能。较低的 AFS 与第一胎的 SLMIX 评分较低（P=0.031）相关。第一胎的 SLMIX 评分与繁殖性能之间没有关联，而第二胎的 SLMIX 评分较高的母猪在哺乳期有更多的仔猪死亡（P=0.027）和更长的周期长度（P=0.003）。第一胎 SLMIX 评分较高的母猪在第二胎的非生产天数（P<0.001）更多。第一胎的 CON 母猪的 SLMIX 评分高于 RUB 母猪（P=0.015），但第二胎没有。此外，与 RUB 母猪相比，CON 母猪在第二胎的死产仔猪比例更高（P=0.013）。混合攻击对胎内繁殖性能有负面影响，并且可能对后续胎次的繁殖性能产生长期的负面影响。让后备母猪更早配种可以帮助减少混合时的攻击性强度，而饲养在橡胶地板上对它们的繁殖性能有有益的影响。
