Kawashima Chiho, Oie Hako, Mashimo Riku, Goto Akira, Kusaba Nobuyuki, Yamagishi Norio
Field Center of Animal Science and Agriculture, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan.
Department of Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan.
J Anim Physiol Anim Nutr (Berl). 2023 Jan;107(1):28-36. doi: 10.1111/jpn.13695. Epub 2022 Feb 25.
This study aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on blood metabolites and calf growth. Forty multiparous Holstein dams were selected based on parity, body condition score, and expected calving date, and randomly assigned to a group: with RPL (n = 22) or without (control [CON], n = 18). RPL dams were supplied daily with 80 g of RPL from Day 21 before the expected calving date to parturition. Blood samples were obtained from the dams before the start of supplementation, 1 week before calving, and immediately after calving, and from calves immediately after birth and weekly until 8 weeks of age. Body weight measurements were performed immediately after birth in all calves and at weekly intervals until 8 weeks of age in female calves. No significant difference was observed in serum metabolite levels and plasma amino acid concentrations between the RPL and CON dams before supplementation, whereas plasma lysine concentrations tended to be higher in RPL dams immediately after calving (p = 0.07). Serum total protein levels (p < 0.05) were higher, whereas plasma total amino acid, total essential amino acid, total non-essential amino acid, and other amino acid concentrations were lower in the calves of RPL dams than those of CON dams (p < 0.05). There were no significant differences in calf birth weight between the two groups, although female calves of RPL dams (n = 7) had higher serum total protein (p < 0.05) and tended to have greater body weight (p = 0.09) from 1 to 8 weeks of age than those of CON dams (n = 11). Overall, RPL supplementation during the close-up period may increase placenta-mediated amino acid transfer to the foetus and enhance protein synthesis in the calf, leading to improved weight gain during the suckling period.
本研究旨在评估围产期补充瘤胃保护性赖氨酸（RPL）对血液代谢物和犊牛生长的影响。根据胎次、体况评分和预期产犊日期选择了40头经产荷斯坦奶牛，并随机分为两组：补充RPL组（n = 22）和不补充组（对照组[CON]，n = 18）。从预期产犊日期前21天到分娩，每天给补充RPL的奶牛供应80克RPL。在补充开始前、产犊前1周、产犊后立即从奶牛采集血样，在犊牛出生后立即以及每周直至8周龄时采集血样。对所有犊牛在出生后立即进行体重测量，对雌性犊牛每周测量一次体重直至8周龄。在补充前，RPL组和对照组奶牛的血清代谢物水平和血浆氨基酸浓度无显著差异，而产犊后立即测定时，RPL组奶牛的血浆赖氨酸浓度有升高趋势（p = 0.07）。RPL组奶牛所产犊牛的血清总蛋白水平较高（p < 0.05），而血浆总氨基酸、总必需氨基酸、总非必需氨基酸和其他氨基酸浓度低于对照组奶牛所产犊牛（p < 0.05）。两组犊牛出生体重无显著差异，尽管RPL组的雌性犊牛（n = 7）在1至8周龄时血清总蛋白较高（p < 0.05），且体重有增加趋势（p = 0.09），高于对照组的雌性犊牛（n = 11）。总体而言，围产期补充RPL可能会增加胎盘介导的氨基酸向胎儿的转运，并增强犊牛的蛋白质合成，从而导致哺乳期体重增加改善。
