USDA-ARS, Livestock Behavior Research Unit, West Lafayette, IN 47907, USA.
Department of Animal Sciences, The Ohio State University, Columbus, OH 43210, USA.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae011.
The objective of this study was to determine the impact of 0, 1, 2, or 3 d of oral electrolyte solutions (OES) following transport on calf behavior, biochemical measures of hydration, and subsequent health. Two cohorts of 60 Holstein bull calves ~3 to 7 d of age were included in this experiment. Calves (n = 30/treatment) were randomized to 1 of 4 treatments on arrival at a calf-raising facility: (1) 1-d OES, (2) 2-d OES, (3) 3-d OES, or (4) no OES (control). Calves were evaluated for signs of arthritis, depression, dehydration, diarrhea, fever, navel inflammation, and respiratory disease on arrival (day 0) and 1, 2, 3, and 7 d after arrival. Blood was obtained following each examination to assess biochemical measures of hydration, including serum electrolytes, glucose, hematocrit, lactate, pH, and serum total protein (STP). Calves were fitted with 3D accelerometers attached to the right hind leg along the metatarsus bone to continuously measure lying time. Linear regression models with Gaussian or Poisson link functions were used to test differences between treatments in blood parameters, as well as disease frequency and behavior, respectively. Calves spent the most time lying immediately post-transport (day 0); however, there was no effect of OES treatment on lying time. On arrival, 90% (95% CI: 84.6% to 95.4%) of calves had mild to moderate dehydration, and there was no significant difference in hydration status across treatments. Mildly dehydrated calves that received 1- and 2-d OES had higher STP concentration compared to the control. Moderately dehydrated calves that received 3- vs. 1-d OES had higher (101.4 vs. 93.7 mmol/L, respectively; P = 0.01) glucose concentration, and 3- vs. 2-d OES (101.4 vs. 96.2, respectively; P = 0.07) calves tended to have higher glucose concentration. The prevalence of failed transfer of passive immunity (STP < 5.1 g/dL) and hypoglycemia (glucose < 4.95 mmol/L) was 26.7% (18.6% to 34.7%) and 76.5% (68.7% to 84.2%), respectively. The frequency of moderate dehydration was lower for calves that received 2-d OES compared to the control (count ratio: 0.4; 0.2% to 0.8%; P = 0.009). These results underline the need for more research on rehydration strategies to help inform calf processing protocols. Future research should investigate preconditioning strategies to minimize the impact of marketing and transport on dairy calves. Continued nutritional-based research is also needed to better support calves' recovery post-transport.
本研究旨在确定在运输后口服电解质溶液(OES) 0、1、2 或 3 天对小牛行为、水合作用的生化指标以及随后的健康状况的影响。该实验纳入了 2 个 60 头荷斯坦公牛小牛队列,年龄在 3 至 7 天之间。小牛(n = 30/处理)在到达牛饲养设施时随机分为 4 种处理之一:(1)1 天 OES,(2)2 天 OES,(3)3 天 OES,或(4)无 OES(对照)。小牛在到达(第 0 天)和到达后 1、2、3 和 7 天评估关节炎、抑郁、脱水、腹泻、发热、脐炎和呼吸道疾病的迹象。每次检查后采集血液以评估水合作用的生化指标,包括血清电解质、葡萄糖、红细胞压积、乳酸、pH 值和血清总蛋白(STP)。将 3D 加速度计安装在右侧后腿的跖骨上,以连续测量小牛的卧姿时间。使用具有高斯或泊松链接功能的线性回归模型来测试血液参数、疾病频率和行为之间的处理差异。小牛在运输后立即花费最多的时间躺着(第 0 天);然而,OES 处理对卧姿时间没有影响。到达时,90%(95%CI:84.6%至 95.4%)的小牛有轻度至中度脱水,且各处理之间的水合状态没有显著差异。接受 1 天和 2 天 OES 的轻度脱水小牛的 STP 浓度较高,与对照组相比。与 1 天 OES 相比,接受 3 天 OES 的中度脱水小牛的葡萄糖浓度更高(分别为 101.4 比 93.7mmol/L,P = 0.01),而接受 3 天 OES 的小牛葡萄糖浓度有升高趋势(分别为 101.4 比 96.2mmol/L,P = 0.07)。被动免疫转移失败(STP <5.1g/dL)和低血糖(葡萄糖 <4.95mmol/L)的患病率分别为 26.7%(18.6%至 34.7%)和 76.5%(68.7%至 84.2%)。与对照组相比,接受 2 天 OES 的小牛中度脱水的频率较低(计数比:0.4;0.2%至 0.8%;P = 0.009)。这些结果强调了需要进一步研究补液策略,以帮助制定小牛处理方案。未来的研究应调查预适应策略,以最大限度地减少营销和运输对奶牛小牛的影响。还需要持续的基于营养的研究,以更好地支持小牛在运输后的恢复。