Department of Animal Sciences and Industry, Kansas State University, Manhattan, Kansas, United States of America.
PLoS One. 2013 Nov 19;8(11):e80316. doi: 10.1371/journal.pone.0080316. eCollection 2013.
Inflammation may be a major contributing factor to peripartum metabolic disorders in dairy cattle. We tested whether administering an inflammatory cytokine, recombinant bovine tumor necrosis factor-α (rbTNFα), affects milk production, metabolism, and health during this period. Thirty-three Holstein cows (9 primiparous and 24 multiparous) were randomly assigned to 1 of 3 treatments at parturition. Treatments were 0 (Control), 1.5, or 3.0 µg/kg body weight rbTNFα, which were administered once daily by subcutaneous injection for the first 7 days of lactation. Statistical contrasts were used to evaluate the treatment and dose effects of rbTNFα administration. Plasma TNFα concentrations at 16 h post-administration tended to be increased (P<0.10) by rbTNFα administration, but no dose effect (P>0.10) was detected; rbTNFα treatments increased (P<0.01) concentrations of plasma haptoglobin. Most plasma eicosanoids were not affected (P>0.10) by rbTNFα administration, but 6 out of 16 measured eicosanoids changed (P<0.05) over the first week of lactation, reflecting elevated inflammatory mediators in the days immediately following parturition. Dry matter and water intake, milk yield, and milk fat and protein yields were all decreased (P<0.05) by rbTNFα treatments by 15 to 18%. Concentrations of plasma glucose, insulin, β-hydroxybutyrate, non-esterified fatty acids, triglyceride, 3-methylhistidine, and liver triglyceride were unaffected (P>0.10) by rbTNFα treatment. Glucose turnover rate was unaffected (P=0.18) by rbTNFα administration. The higher dose of rbTNFα tended to increase the risk of cows developing one or more health disorders (P=0.08). Taken together, these results indicate that administration of rbTNFα daily for the first 7 days of lactation altered inflammatory responses, impaired milk production and health, but did not significantly affect liver triglyceride accumulation or nutrient metabolism in dairy cows.
炎症可能是奶牛围产期代谢紊乱的一个主要因素。我们测试了在这一时期，给奶牛注射一种炎症细胞因子，重组牛肿瘤坏死因子-α（rbTNFα），是否会影响产奶量、新陈代谢和健康。33 头荷斯坦奶牛（9 头初产和 24 头经产）在分娩时被随机分配到 3 种处理组中的 1 种。处理组为 0（对照组）、1.5 或 3.0μg/kg 体重 rbTNFα，在哺乳期的前 7 天每天通过皮下注射给药 1 次。采用统计对比来评估 rbTNFα 给药的处理和剂量效应。rbTNFα 给药后 16 小时的血浆 TNFα 浓度有升高的趋势（P<0.10），但未检测到剂量效应（P>0.10）；rbTNFα 处理增加了（P<0.01）血浆触珠蛋白的浓度。大多数血浆类二十烷酸没有受到 rbTNFα 给药的影响（P>0.10），但在哺乳期的第一周有 16 种测量的类二十烷酸中有 6 种发生了变化（P<0.05），反映了分娩后几天内炎症介质的升高。干物质和水的摄入、产奶量以及牛奶脂肪和蛋白质的产量都因 rbTNFα 处理而降低了 15-18%（P<0.05）。血浆葡萄糖、胰岛素、β-羟丁酸、非酯化脂肪酸、甘油三酯、3-甲基组氨酸和肝甘油三酯的浓度不受 rbTNFα 处理的影响（P>0.10）。葡萄糖周转率不受 rbTNFα 给药的影响（P=0.18）。较高剂量的 rbTNFα 使奶牛发生一种或多种健康疾病的风险增加（P=0.08）。综上所述，这些结果表明，在哺乳期的前 7 天每天注射 rbTNFα 会改变炎症反应，降低产奶量和健康水平，但不会显著影响奶牛肝甘油三酯的积累或营养代谢。
