Montes Maria Elisa, Brunton Mercedes, Mann Adrianna, Teeple Kelsey, George Uduak, Boerman Jacquelyn, Casey Theresa
Department of Animal Sciences, Purdue University, West Lafayette, IN 47907.
Department of Mathematics and Statistics, San Diego State University, San Diego, CA 92182-7720.
JDS Commun. 2023 Mar 2;4(4):308-312. doi: 10.3168/jdsc.2022-0327. eCollection 2023 Jul.
Animal behavior and management factors that influence behavior affect physiology and lactation performance. Circadian rhythms of core body temperature are a primary output of the master clock; however, core body temperature in early-lactation dairy cows showed poor fit to 24-h rhythms. We hypothesized that eating behavior was related to daily body temperature oscillations. The objectives of this study were to determine if oscillations in daily behaviors, specifically feeding behavior, were related to body temperature. The behavior of 11 Holstein cows (34 ± 14 d in milk; mean ± standard deviation) housed in a freestall barn was recorded every 10 min for a 48-h period. Simultaneously, data loggers (iButtons; iButtonLink Technology) recorded the body temperature of cows with the same sampling frequency. The mean temperature of all cows showed a better fit to a 2-component cosinor (R = 0.54) than to a single cosinor model (R = 0.26). Logistic regression showed that the probability (Pr) of a cow experiencing an increase in body temperature (increment, I) given that she was milking [Pr(I|milking) = 0.94] was higher than for ruminating [Pr(I|ruminating) = 0.69], lying [Pr(I|lying) = 0.66], feeding [Pr(I|feeding) = 0.16], standing [Pr(I|standing) = 0.54], and mounting [Pr(I|mounting) = 0.62]. The main limitations of this study are the length of the observation period and the sample size. Longer observation windows on core body temperature would allow to isolate the noise and the signal and identify patterns with more clarity. Oscillations in body temperature were not associated with feeding. However, findings indicate that milking, activity associated with walking to the parlor, or the temperature in the parlor may affect secondary rhythms of daily body temperature.
影响行为的动物行为和管理因素会影响生理和泌乳性能。核心体温的昼夜节律是主时钟的主要输出；然而，初产奶牛的核心体温与24小时节律的拟合度较差。我们假设进食行为与每日体温波动有关。本研究的目的是确定日常行为的波动，特别是采食行为，是否与体温有关。在一个自由牛舍中饲养的11头荷斯坦奶牛（产奶34±14天；平均值±标准差）的行为，在48小时内每10分钟记录一次。同时，数据记录器（iButtons；iButtonLink Technology）以相同的采样频率记录奶牛的体温。所有奶牛的平均体温与双成分余弦模型（R=0.54）的拟合度优于单余弦模型（R=0.26）。逻辑回归表明，奶牛在挤奶时体温升高（增量，I）的概率[Pr（I|挤奶）=0.94]高于反刍[Pr（I|反刍）=0.69]、躺卧[Pr（I|躺卧）=0.66]、采食[Pr（I|采食）=0.16]、站立[Pr（I|站立）=0.54]和爬跨[Pr（I|爬跨）=0.62]时。本研究的主要局限性在于观察期的长度和样本量。对核心体温进行更长时间的观察窗口将有助于分离噪声和信号，并更清晰地识别模式。体温波动与采食无关。然而，研究结果表明，挤奶、与走向挤奶厅相关的活动或挤奶厅的温度可能会影响每日体温的次级节律。
