Zhao Wei, Chen Xue, Xiao Jun, Chen Xiao Hui, Zhang Xue Feng, Wang Tao, Zhen Yu Guo, Qin Gui Xin
College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
JLAU-Borui Dairy Science and Technology R&D Centre of Jilin Agricultural University, Changchun 130118, China.
Asian-Australas J Anim Sci. 2019 Dec 1;32(12):1889-1896. doi: 10.5713/ajas.18.0817. Epub 2019 Apr 15.
This study aimed to investigate the effects of prepartum body condition score (BCS) on the milk yield, lipid metabolism, and oxidative status of Holstein cows.
A total of 112 multiparous Holstein cows were divided into 4 groups according to the BCS at 21 days before calving: medium BCS (3.03.25, MBCS), high BCS (3.53.75, HBCS), higher BCS (4.04.25, HerBCS), and highest BCS (4.55.0, HestBCS). Blood samples were collected on 21, 14, and 7 days before calving (precalving), on the calving day (calving), and on 7, 14, and 21 days after calving (postcalving). The indices of lipid metabolism and oxidative status were analyzed using bovine-specific ELISA kit. Colostrum were taken after calving and analyzed by a refractometer and milk analyzer. The individual milk yield was recorded every 3 days.
The density and levels of immune globulin and lactoprotein of colostrum from Holstein cows in the HestBCS group were the highest (p<0.05). These animals not only had the highest (p<0.05) levels of serum non-esterified fatty acids and beta-hydroxybutyrate, but also had the highest (p<0.05) levels of malondialdehyde, superoxide dismutase, catalase, vitamin A, and vitamin E. In addition, greater (p<0.05) BCS loss was observed in the HestBCS cows.
This study demonstrates that the milk yield, lipid metabolism, and oxidative status of Holstein cows are related to prepartum BCS and BCS loss during the transition period. HestBCS cows are more sensitive to oxidative stress and suffer greater loss of BCS after calving, whereas the MBCS animals had better milk yield performance.
本研究旨在探讨产前体况评分（BCS）对荷斯坦奶牛产奶量、脂质代谢和氧化状态的影响。
根据产犊前21天的BCS，将112头经产荷斯坦奶牛分为4组：中等BCS（3.03.25，MBCS）、高BCS（3.53.75，HBCS）、较高BCS（4.04.25，HerBCS）和最高BCS（4.55.0，HestBCS）。在产犊前21天、14天和7天、产犊当天以及产犊后7天、14天和21天采集血样。使用牛特异性ELISA试剂盒分析脂质代谢和氧化状态指标。产犊后采集初乳，用折射仪和牛奶分析仪进行分析。每3天记录个体产奶量。
HestBCS组荷斯坦奶牛初乳中免疫球蛋白和乳蛋白的密度和水平最高（p<0.05）。这些动物不仅血清非酯化脂肪酸和β-羟基丁酸水平最高（p<0.05），而且丙二醛、超氧化物歧化酶、过氧化氢酶、维生素A和维生素E水平也最高（p<0.05）。此外，HestBCS奶牛的BCS损失更大（p<0.05）。
本研究表明，荷斯坦奶牛的产奶量、脂质代谢和氧化状态与产前BCS以及过渡期的BCS损失有关。HestBCS奶牛对氧化应激更敏感，产犊后BCS损失更大，而MBCS动物的产奶性能更好。
