Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5, Canada.
Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5, Canada; Animal Inframetrics Inc., Box 5451, Lacombe, AB T4L 1X2, Canada.
Animal. 2022 Aug;16(8):100585. doi: 10.1016/j.animal.2022.100585. Epub 2022 Jul 25.
The primary objective of this study was to develop an automated infrared thermography platform (Estrus BenchMark) capable of measuring skin temperature and tail movements as a means of identifying cows in estrus. The secondary objective was to evaluate the accuracy of Estrus BenchMark to detect estrus compared to in-line milk progesterone (P) analysis (Herd Navigator System) in a commercial dairy herd managed under a robotic milking system. Data were collected on forty-six cows from 45 to 120 d after calving. Cows were flagged in estrus when milk P fell below 5 ng/mL. The Estrus BenchMark true positive estrus alerts (Sensitivity; Se%) were compared to Herd Navigator System estrus alerts at different time-windows (±12 h, ±24 h, ±48 h, and ±72 h) relative to the Estrus BenchMark estrus alerts for all the estrus alerts (AE) and confidence-quality estrus (CQE; >80% quality) alerts identified by Herd Navigator System. The Estrus BenchMark captured skin temperature and tail movements resulting in vulva exposure (left tail movements, LTail; right tail movements, RTail; and pooled tail movements, PTail) for each milking event. Skin temperature tended to increase when the milk P concentration (Least-Squares Means ± SE) dropped for AE (estrus day [d 0]; P; 3.51 ± 0.05 ng/mL, Skin temperature; 33.31 ± 2.38 °C) compared with d -7 (P; 20.22 ± 0.73 ng/mL; Skin temperature: 32.05 ± 3.77 °C). The increase in skin temperature, however, was significant in cows with CQE > 80% at d 0 (32.75 ± 0.29 °C) compared to d -7 (31.80 ± 0.28 °C). The prevalence of tail movements to expose vulva was greater (P = 0.01) in AE at d 0 (LTail: 62.50%; PTail; 68.75%; and RTail: 56.25%) compared with d -7 (LTail: 18.75%; PTail: 9.37%: and RTail: 9.37%), and d +4 (LTail: 9.37%; PTail: 9.37%; and RTail: 12.5%). Moreover, the higher prevalence of tail movements at d 0 was observed in cows with CQE > 80% (LTail; 65%, PTail; 80%, and RTail; 70%) compared to those with CQE < 80%. The highest Estrus BenchMark Youden index (YJ; 0.45), diagnostic odds ratio (DOR; 9.04), and Efficiency (0.77) were achieved for AE in a ±48 h window and at ±72 h window for CQE (YJ; 0.66, DOR; 25.29, and Efficiency 0.76) relative to Herd Navigator System estrus alerts. The highest Estrus BenchMark resulted in 58% estrus detection rates for AE and 80% for cows with CQE compared to the Herd Navigator System.
本研究的主要目的是开发一种自动化的红外热成像平台（发情 BenchMark），能够测量皮肤温度和尾巴运动，以此识别发情牛。次要目的是评估 Estrus BenchMark 与在线牛奶孕激素（P）分析（Herd Navigator System）相比，在使用机器人挤奶系统管理的商业奶牛场中检测发情的准确性。在产后 45 至 120 天内，对 46 头奶牛进行了数据收集。当牛奶 P 下降到 5ng/mL 以下时，奶牛被标记为发情。Estrus BenchMark 的真阳性发情警报（敏感性；Se%）与 Herd Navigator System 在不同时间窗口（±12 小时、±24 小时、±48 小时和±72 小时）的发情警报进行了比较，这些发情警报是根据 Herd Navigator System 识别的所有发情警报（AE）和置信质量发情（CQE；>80%质量）警报确定的。Estrus BenchMark 捕获了皮肤温度和尾巴运动，导致外阴暴露（左尾运动，LTail；右尾运动，RTail；和尾运动总和，PTail）在每次挤奶事件中。当牛奶 P 浓度（最小二乘均值±SE）下降时，皮肤温度往往会升高（发情日 [d0]；P；3.51±0.05ng/mL，皮肤温度；33.31±2.38°C）与 d-7 相比（P；20.22±0.73ng/mL；皮肤温度：32.05±3.77°C）。然而，在 CQE>80%的奶牛中，d0 时的皮肤温度升高更为显著（32.75±0.29°C），与 d-7 时（31.80±0.28°C）相比。在外阴暴露的尾巴运动方面，发情日（d0）的尾巴运动更为常见（P=0.01），LTail：62.50%；PTail：68.75%；和 RTail：56.25%）与 d-7 相比（LTail：18.75%；PTail：9.37%：和 RTail：9.37%），以及 d+4（LTail：9.37%；PTail：9.37%；和 RTail：12.5%）。此外，在 CQE>80%的奶牛中，d0 时尾巴运动的发生率更高（LTail：65%，PTail：80%，RTail：70%）与 CQE<80%的奶牛相比。Estrus BenchMark 的最高 Youden 指数（YJ；0.45）、诊断比值比（DOR；9.04）和效率（0.77）是在±48 小时窗口内对 AE 获得的，在±72 小时窗口内对 CQE（YJ；0.66，DOR；25.29，和效率 0.76）与 Herd Navigator System 发情警报相比。Estrus BenchMark 的发情检测率最高，AE 为 58%，CQE 为 80%，而 Herd Navigator System 为 80%。
