Department of Animal Medicine, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 91540-000, Brazil.
Department of Animal Medicine, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 91540-000, Brazil.
Animal. 2024 Oct;18(10):101247. doi: 10.1016/j.animal.2024.101247. Epub 2024 Jul 22.
The number of piglets born alive is frequently greater than the functional teats, and some farms are equalizing litters with surplus piglets, limiting piglet udder access. Removing the barrier among farrowing crates may allow piglets to socialize and seek other sows. Thus, we evaluated the effects litter size at cross-fostering and socialization on the sow and piglet performance during lactation. Two factors were included in a 2 × 2 factorial design: socialization and litter size relative to sow functional teat number at cross-fostering. Litters (n = 189) were then assigned to one of four groups: CONT+0 (litters not co-mingled with no additional piglet), CONT+1 (not co-mingled with one additional piglet), Co-M+0 (co-mingled with no additional piglet), Co-M+1 (co-mingled with one additional piglet). Piglets were cross-fostered from 12-16 h after birth, and 24 h later, Co-M groups were socialized by removing the barrier between two adjacent pens. During lactation, sows lost more caliper units in the + 1 group than in the + 0 group (P = 0.04). The number of functional teats did not differ among groups, but Co-M sows had a higher udder lesion score at weaning than CONT (6.55 vs 4.83; P < 0.01). Furthermore, +1 sows had fewer vacant teats throughout lactation (P < 0.01). Milk yield did not differ among the groups (P ≥ 0.13). Regarding the number of weaned piglets, no difference was observed for socialization (P = 0.84), but + 1 sows weaned 0.67 more piglets than + 0 (P < 0.01). Although CONT+0 had the heaviest piglets at weaning (P < 0.01), litter weight did not differ among the groups (P ≥ 0.08). Facial and joint lesions were frequently observed in Co-M (P < 0.01) than CONT. Piglet loss rate did not differ among treatments (overall rate = 12.6%; P ≥ 0.26). The removal rate, however, was more frequent in + 1 litters than in + 0 (P < 0.01). Death due to starvation was higher in CONT+1 than CONT+0 (P < 0.01) but did not differ between the Co-M groups (P = 0.99). Litters formed with one additional piglet relative to functional teat number weaned more piglets, albeit with lower individual weight. Litter socialization may alleviate the impact of high litter size but shows greater percentages of udder injuries and facial and joint lesions in weaned piglets.
仔猪的出生数通常多于功能性乳头数，一些农场通过调整窝产仔数来平衡多余的仔猪，限制仔猪对乳头的接触。在分娩栏之间移除障碍物可能会使仔猪进行社交并寻找其他母猪。因此，我们评估了寄养时的窝产仔数和社会化对哺乳期母猪和仔猪性能的影响。在 2×2 析因设计中包含了两个因素：社会化和寄养时相对于母猪功能性乳头数的窝产仔数。然后将 189 窝仔猪分配到四个组之一：CONT+0（未与其他仔猪混合，没有额外的仔猪）、CONT+1（未与其他仔猪混合，但有一头额外的仔猪）、Co-M+0（与其他仔猪混合，但没有额外的仔猪）、Co-M+1（与其他仔猪混合，有一头额外的仔猪）。仔猪在出生后 12-16 小时被寄养，24 小时后，Co-M 组通过移除两个相邻围栏之间的障碍物进行社会化。在哺乳期，+1 组的母猪比+0 组损失了更多的卡尺单位（P=0.04）。各组之间功能性乳头数没有差异，但 Co-M 母猪在断奶时的乳房损伤评分高于 CONT（6.55 对 4.83；P<0.01）。此外，+1 组母猪在整个哺乳期的空乳头数更多（P<0.01）。各组的产奶量没有差异（P≥0.13）。关于断奶仔猪的数量，社会化没有差异（P=0.84），但+1 组母猪断奶的仔猪比+0 组多 0.67 头（P<0.01）。尽管 CONT+0 组的仔猪在断奶时最重（P<0.01），但各组的窝重没有差异（P≥0.08）。Co-M 组的面部和关节损伤比 CONT 组更常见（P<0.01）。仔猪死亡率在各组之间没有差异（总体死亡率为 12.6%；P≥0.26）。然而，+1 窝的淘汰率高于+0 窝（P<0.01）。由于饥饿而死亡的仔猪在 CONT+1 组高于 CONT+0 组（P<0.01），但 Co-M 组之间没有差异（P=0.99）。与功能性乳头数相比，窝产仔数增加一头的窝产仔数断奶的仔猪更多，但个体体重较低。窝社会化可能会减轻大窝产仔数的影响，但会增加断奶仔猪的乳房损伤、面部和关节损伤的比例。
