Dairy Cows Experimentally Infected With Bovine Leukemia Virus Showed an Increased Milk Production in Lactation Numbers 3-4: A 4-Year Longitudinal Study.
Dairy Cows Experimentally Infected With Bovine Leukemia Virus Showed an Increased Milk Production in Lactation Numbers 3-4: A 4-Year Longitudinal Study.
复制标题
DOI：
10.3389/fmicb.2022.946463
复制
发表时间：
2022
影响因子：
5.2
通讯作者：
中科院分区：
文献类型：
--
作者：
牛白血病病毒（BLV）在全球牛群中广泛存在，但其感染对牛奶产量和质量的影响尚未在动物模型中明确阐明。在这项研究中，30头健康的第一次泌乳奶牛从102988头奶牛在一个无BLV的农场，具有相同的标准，胎次，年龄，泌乳次数，以及产奶量，SCS，和组成（脂肪，蛋白质和乳糖）。随后，这些奶牛被随机分配到干预组（n = 15）或对照组（n = 15），并在不同的牛棚饲养。干预组的奶牛接种1 ×磷酸盐缓冲液（PBS），该溶液重悬于BLV阳性奶牛的外周血单核细胞（PBMC）中，而对照组接种同一个体的灭活PBMC。从2016年6月至2021年7月，牛奶重量（kg）由牛奶传感器自动记录，牛奶SCS和成分来自每月进行的奶牛群改良（DHI）测试。荧光共振能量转移（FRET）-qPCR和ELISA显示，干预组的奶牛成功感染了BLV，而对照组的奶牛在整个期间没有BLV。接种后45天（DPI），全血细胞（WBC）数量（P = 0.010），淋巴细胞（LYM）（P = 0.002）和单核细胞（MNC）与未感染的奶牛相比，BLV感染的奶牛中IFN-γ（P = 0.013）、IL-10（P = 0.031）和IL-12 p70（P = 0.008）的表达水平显著增加。在第2-4次泌乳中，干预组的总产奶量（P < 0.001）、脂肪（P = 0.031）和蛋白质（P = 0.050）显著高于对照组，而乳SCS（P = 0.038）和乳糖（P = 0.036）显著降低。进一步分析表明，BLV感染与第3-4泌乳期各泌乳阶段的产奶量增加有关（P = 0.021或P < 0.001），但与SCS和乳成分无关。总之，这项为期4年的纵向研究表明，人工接种BLV增加了该BLV攻毒模型中奶牛的产奶量。
Bovine leukemia virus (BLV) is widespread in global cattle populations, but the effects of its infection on milk quantity and quality have not been clearly elucidated in animal models. In this study, 30 healthy first-lactation cows were selected from ≈2,988 cows in a BLV-free farm with the same criteria of parity, age, lactation number, as well as milk yield, SCS, and composition (fat, protein, and lactose). Subsequently, these cows were randomly assigned to the intervention (n = 15) or control (n = 15) group, and reared in different cowsheds. Cows in the intervention group were inoculated with 1 × phosphate-buffered solution (PBS) resuspended in peripheral blood mononuclear cells (PBMC) from a BLV-positive cow, while the controls were inoculated with the inactivated PBMC from the same individual. From June 2016 to July 2021, milk weight (kg) was automatically recorded by milk sensors, and milk SCS and composition were originated from monthly performed dairy herd improvement (DHI) testing. Fluorescence resonance energy transfer (FRET)–qPCR and ELISA showed that cows in the intervention group were successfully infected with BLV, while cows in the control group were free of BLV for the entire period. At 45 days post-inoculation (DPI), the numbers of whole blood cells (WBCs) (P = 0.010), lymphocytes (LYMs) (P = 0.002), and monocytes (MNCs) (P = 0.001) and the expression levels of IFN-γ (P = 0.013), IL-10 (P = 0.031), and IL-12p70 (P = 0.008) increased significantly in the BLV infected cows compared to the non-infected. In lactation numbers 2–4, the intervention group had significantly higher overall milk yield (P < 0.001), fat (P = 0.031), and protein (P = 0.050) than the control group, while milk SCS (P = 0.038) and lactose (P = 0.036) decreased significantly. Further analysis indicated that BLV infection was associated with increased milk yield at each lactation stage in lactation numbers 3–4 (P = 0.021 or P < 0.001), but not with SCS and milk composition. Together, this 4-year longitudinal study revealed that artificial inoculation of BLV increased the milk yield in cows in this BLV challenge model.
影响因子：
3.7
作者：
Yang Y;Kelly PJ;Bai J;Zhang R;Wang C
通讯作者：
Wang C