Abstract #43

# 43
Which data recorded by automated calf feeders can help to detect sick calves?
C. Medrano-Galarza*1,5, S. J. LeBlanc1,5, T. J. DeVries2,5, J. Rushen3, A. M. de Passillé3, A. Jones-Bitton1, M. I. Endres4, D. B. Haley1,5, 1Department of Population Medicine, University of Guelph, Guelph, ON, Canada, 2Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada, 3Faculty of Land and Food, University of British Columbia, Vancouver, BC, Canada, 4Department of Animal Science, University of Minnesota, St. Paul, MN, 5Campbell Centre for the Study of Animal Welfare, University of Guelph, Guelph, ON, Canada.

Automated calf feeders continuously record individual calf feeding behavior data that could help detect illness before clinical signs and monitor recovery. The aim of this study was to evaluate the association between calf health status and milk feeding behavior. Thirty-seven dairy calves with diarrhea or respiratory disease from 2 farms in Ontario, using high milk allowance (9 to 10 L/d), were pair-matched to healthy calves by days on the feeder. Data collected by the feeder for each calf were daily milk intake, drinking speed and duration of each visit, and frequency of visits. The day producers treated a sick calf corresponded to d0. Data from 7 d before and after d0 were analyzed. Differences in daily feeding behavior between sick and healthy calves were evaluated using a repeated measures general linear mixed model. Day, health status, farm, and the interaction between day and health status were included as fixed effects. Matched-pair identification was included as a random effect. Compared with healthy calves, sick calves drank less milk in the 5 d before treatment (d−5: −0.9L, P = 0.03; d−4: −1.1L, P < 0.01; d−3: −1.6L, P < 0.001; d−2: −1.7L, P < 0.001; d−1: −2.4L, P < 0.001), d0 (d0: −2.1L, P < 0.001), and the 2 d following treatment (d+1: −1.1L, P < 0.01; d+2: −1.0L, P = 0.01). Among healthy calves, there were no differences in milk intake between days, whereas for sick calves, there was a drop (P < 0.001) in milk intake from d−5 (6.8L/d) to d0 (5.2 L/d), and an increase (P < 0.001) after treatment day until d+5 (7.4L/d). Sick calves drank more slowly than healthy calves (mean speed: 0.4 vs. 0.6 L/min, P < 0.001). Among sick calves, drinking speed dropped between d−1 and d0 (0.06 L/min; P = 0.01), and increased after treatment by 0.07 L/min on d+1 (P = 0.01), and by 0.1 L/min on d+5 (P < 0.001). There was no association of day and no health status Ă— day interaction for the frequency of visits to the feeder or visit duration. In summary, sick calves started to decrease milk intake 5 d before treatment, and drank more slowly only on the day before treatment. Therefore, milk intake could be a useful indicator to help detect sick calves and monitor recovery.

Key Words: calf, health, feeding behaviour