Thermal Profiles: Novel phenotypic measurements of animal growth and metabolic efficiency.

The costs of production for high density protein and the impacts food production have on the environment are becoming increasingly important issues in animal agriculture. The objective of the present study was to investigate the use of novel thermal profiles including a Thermal Efficiency Index (TEI) on the ability to identify efficient animals in a fraction of the time and at a significantly lower cost of conventional feed station and performance technology. Three hundred and fourty four high performance Duroc sires from a genetic nucleus herd were used in the study. The animals were monitored for feed consumption and growth performance using conventional feed station technology for a 72 day period. Animals were monitored in these stations between approximately 50 kg and 130 kg live body weight. An infrared thermal scan was performed on the animals at the end of the performance test by collecting automated dorsal thermal images and using these biometrics to measure both bio-surveillance values and a thermal phenotypic profile including the TEI (mean dorsal temperature /body weight 0.75). The thermal profile values were significantly correlated (r = 0.40, P < 0.0001) with a current industry best practice for performance in Residual Intake and Gain (RIG). The data from the current study suggest these rapid, real time, cost effective values for TEI constitute a useful precision farming tool for the animal industries to reduce the cost of production and green house gas (GHG) impact for high density protein production.

Evaluating automated infrared thermography and vulva exposure tracking as components of an estrus detection platform in a commercial dairy herd.

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 (P4) 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 P4 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 P4 concentration (Least-Squares Means ±â€¯SE) dropped for AE (estrus day [d 0]; P4; 3.51 ±â€¯0.05 ng/mL, Skin temperature; 33.31 ±â€¯2.38 °C) compared with d -7 (P4; 20.22 ±â€¯0.73 ng/mL; Skin temperature: 32.05 ±â€¯3.77 °C). The increase in skin temperature, however, was significant in cows with CQE > 80% at d 0 (32.75 ±â€¯0.29 °C) compared to d -7 (31.80 ±â€¯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.

Energy utilization in cattle with steady state and non-steady state methods: the importance of thermal neutrality.

The efficiency by which animals utilize dietary energy is fundamental to the cost of production for protein of animal origin and to the carbon footprint an animal industry has. Hence, the development of cost effective methodology for determining these measurements of efficiency is important. The objective of the present study was to investigate the use of infrared thermography in a rapid, non-steady state method for measuring energy loss in cattle. Data from 241 yearling bulls and steers as well as heifers and mature cows are presented. Infrared images were collected following a 24h feed withdrawal period. The infrared thermal response in these animals was significantly ranked (P < 0.03) with conventional measurements of feed efficiency using residual feed intake values for animals demonstrated to be within a thermal neutral zone. When animals were not within a thermal neutral zone there was no significant ranking. The data suggests that the use of a non-steady state approach using infrared thermography for identifying metabolic efficiency in animals may be a more rapid and less expensive method for identifying differences in energy utilization. The data also demonstrates the importance of maintaining thermal neutrality when measuring metabolic efficiency irrespective of the methodology.