The effects of acute versus chronic health challenges on the behavior of beef cattle.
The effects of acute versus chronic health challenges on the behavior of beef cattle.
复制标题
急性与慢性健康挑战对肉牛行为的影响。
DOI：
10.2527/jas.2011-4765
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发表时间：
2012
影响因子：
3.3
通讯作者：
I. Kyriazakis
中科院分区：
文献类型：
--
作者：
O. Szyszka;B. Tolkamp;S. Edwards;I. Kyriazakis
对与(亚临床)急性和慢性健康挑战相关的行为变化进行了调查，以评估它们对开发肉牛早期疾病检测系统的潜在价值。当时的假设是，急性挑战会导致行为的急性但短暂的变化，而慢性挑战的情况则相反，变化需要更长的时间才能形成，但更持久。为此，荷斯坦-弗里斯安肉牛分别以3次递增剂量静脉注射脂多糖(LPS)，连续5d，或单次注射Osteragia osteragi，分别作为急性和慢性攻击模型。第三组未受质疑的人则充当控制组。定期采集粪便和血液样本，分析粪便卵数(FEC)、胃蛋白酶原浓度和内毒素抗体。每头公牛的前腿上都安装了传感器，以记录它们的活动和姿势。视频记录被用来监控饮酒和进食行为。只有在第三次内毒素攻击后才能检测到内毒素抗体。在感染后3wk检测到粪卵计数，在被寄生的公牛中胃蛋白酶原大致在同一时间升高。感染后17d，寄生动物的体重较对照动物减轻(P<；0.001)，而内毒素组与对照动物的生产性能差异不显著(P>；0.05)。内毒素对行为的影响仅持续几个小时，表现为在第一次攻击后约10小时活动减少(P=0.057)。由寄生虫引起的最明显的行为变化是在姿势上。与对照组相比，寄生动物卧床次数较少(P=0.003)，卧床时间较长(P=0.038)。一旦确定，这些变化持续到感染后30d。然而，以所走的步数或总的卧床时间来衡量，治疗对总体活动没有影响(P>；0.05)。摄食和饮水次数及其持续时间不受健康挑战的影响(P>；0.05)，但被寄生动物的平均摄食持续时间增加(P=0.013)。尽管寄生虫的挑战对行为的几个方面产生了重大影响，但这些可能被认为过于微妙，不能作为疾病的有用指标；然而，当与其他测量一起使用时，它们可能有助于及早发现肉牛的疾病。
The changes in behavior associated with a (subclinical) acute and a chronic health challenge were investigated to assess their potential value for the development of an early disease detection system in beef cattle. The hypothesis was that acute challenges would lead to acute but transient changes in behavior, whereas the converse would be the case during chronic challenges, with changes taking longer to develop, but being more persistent. For this purpose, Holstein-Friesian beef bulls were challenged either with a repeated lipopolysaccharide (LPS) intravenous bolus given at 3 increasing doses over the course of 5 d, or with a single dose of the abomasal parasite Ostertagia ostertagi, acting as models of acute and chronic challenge respectively. A third unchallenged group acted as controls. Fecal and blood samples were taken regularly and analyzed for fecal egg counts (FEC), pepsinogen concentration and LPS antibodies. A sensor was fitted to the front leg of each bull to record activity and posture. Video recordings were taken to monitor drinking and feeding behavior. Antibodies to LPS were detected only after the third LPS challenge. Fecal egg counts were detected 3 wk post infection, and pepsinogen increased roughly at the same time in parasitized bulls. Body weight of parasitized animals was reduced relative to controls after 17 d post infection (P < 0.001), whereas there was no difference in performance between the LPS and control animals (P > 0.05). Effects of LPS on behavior lasted only for a few hours, presenting themselves as reduction in activity approximately 10 h after the first challenge (P = 0.057). The clearest behavioral changes due to parasitism were on posture. Parasitized animals had less frequent (P = 0.003), but longer lying episodes (P = 0.038) than controls. Once established, these changes persisted for 30 d post infection. However, there was no treatment effect on overall activity, measured by the number of steps taken or on total lying time (P > 0.05). Frequency of feeding and drinking episodes and their duration were not affected by health challenge (P > 0.05); however there was an increase in average duration of feeding (P = 0.013) for the parasitized animals. Even though the parasite challenge had significant effects on several aspects of behavior, these may be considered too subtle to be useful indicators of disease; however when used with other measurements, they may prove helpful for the early detection of disease in beef cattle.