Department of Animal Medicine, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre91540-000, Brazil.
Department of Animal Science, Faculty of Agronomy, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre91540-000, Brazil.
Animal. 2020 Sep;14(9):1906-1915. doi: 10.1017/S175173112000049X. Epub 2020 Mar 25.
During weaning-to-estrus interval (WEI), the sows are usually fed with high feed level to improve the reproductive performance. However, the WEI has been reduced over the years which may reduce the impact of feed level on performance in the modern genetic lines. The aim of this study was to evaluate the effect of two feeding levels (moderate feeding level (MFL): 2.7 kg/day and high feeding level (HFL): 4.3 kg/day) and two diet types (gestation: 13.67 MJ/kg of metabolizable energy (ME) and 0.62% of standard ileal digestible lysine (SID Lys) and lactation: 14.34 MJ ME/kg and 1.20% of SID Lys) offered during the WEI on reproductive performance. In total, 19.0% of sows were excluded from the analysis due to feed intake below 75% (9.6% and 28.5% in MFL and HFL groups, respectively), remaining 254 primiparous and 806 multiparous sows. Follicular size and change in BW were measured in subsamples of 180 and 227 females, respectively. Data were analyzed considering the sow as the experimental unit. Feeding level, diet type, parity and their interactions were included as fixed effects, whereas the day of weaning was considered as a random effect. The feed intake of MFL and HFL groups averaged 2.5 ± 0.02 and 3.8 ± 0.02 kg/day, respectively. There was an interaction between feeding level and parity for daily feed intake. Within HFL, multiparous sows consumed 181 g/day more than primiparous sows (P < 0.01), but no difference was observed within MFL (P > 0.05). Both primiparous and multiparous sows lost proportionally less weight when fed HFL than MFL gestation diet during WEI. The percentage of weight loss was lower in HFL than in the MFL group in multiparous sows fed the lactation diet. The WEI was not affected by feeding level, diet type or its interaction (P > 0.05), but it was longer in primiparous than in multiparous sows (P = 0.001). There was no effect of feeding level, diet type, parity or their interactions on anestrus and farrowing rates. Multiparous sows showed greater follicular size, and greater numbers of total born and born alive piglets in the subsequent cycle than primiparous sows (P < 0.05). In conclusion, feeding weaned primiparous and multiparous sows with 4.3 kg/day of a gestation (58.78 MJ ME and 26.66 g SID Lys) or a lactation diet (61.66 MJ ME and 51.60 g SID Lys) does not improve follicular size and reproductive performance in the subsequent cycle.
在断奶至发情间隔（WEI）期间，通常会给母猪饲喂高饲料水平，以提高繁殖性能。然而，近年来 WEI 已经缩短，这可能会降低现代遗传品系中饲料水平对性能的影响。本研究旨在评估两种饲喂水平（适度饲喂水平（MFL）：2.7 kg/天和高饲喂水平（HFL）：4.3 kg/天）和两种日粮类型（妊娠：13.67 MJ/kg 可代谢能（ME）和 0.62%标准回肠可消化赖氨酸（SID Lys）和泌乳：14.34 MJ ME/kg 和 1.20%SID Lys）在 WEI 期间对繁殖性能的影响。共有 19.0%的母猪因采食量低于 75%（MFL 和 HFL 组分别为 9.6%和 28.5%）而被排除在分析之外，剩余 254 头初产母猪和 806 头经产母猪。在分别对 180 头和 227 头母猪的亚样本中测量了卵泡大小和 BW 的变化。数据分析时将母猪作为实验单位。饲喂水平、日粮类型、胎次及其相互作用作为固定效应，而断奶日作为随机效应。MFL 和 HFL 组的平均日采食量分别为 2.5±0.02 和 3.8±0.02 kg/天。日采食量存在饲喂水平和胎次的交互作用。在 HFL 中，经产母猪比初产母猪多采食 181 g/天（P<0.01），但在 MFL 中没有差异（P>0.05）。在 WEI 期间，与饲喂 MFL 妊娠日粮相比，饲喂 HFL 的初产和经产母猪体重损失比例均降低。与 MFL 组相比，HFL 组断奶后母猪的失重率较低。饲喂水平、日粮类型及其相互作用对乏情率和分娩率没有影响（P>0.05），但初产母猪的 WEI 比经产母猪长（P=0.001）。饲喂水平、日粮类型、胎次及其相互作用对乏情率和分娩率没有影响。经产母猪在随后的周期中表现出更大的卵泡大小，以及更多的总产仔数和活产仔数（P<0.05）。综上所述，给断奶的初产和经产母猪饲喂 4.3 千克/天的妊娠（58.78 MJ ME 和 26.66 g SID Lys）或泌乳日粮（61.66 MJ ME 和 51.60 g SID Lys）并不能提高随后周期的卵泡大小和繁殖性能。
