Date of Award

8-2016

Degree Type

Thesis

Degree Name

Master of Science

Major

Animal Science

Major Professor

Peter D. Krawczel

Committee Members

Marc Caldwell, Gina M. Pighetti

Abstract

Cattle experience behavioral changes during incidences of discomfort such as respiratory disease, hock injuries, and lameness. Visual evaluation of these conditions, particularly lameness and respiratory disease can be subjective and may lead to untreated animals, which reduces the overall well-being of the animals. In order to improve detection of affected cattle, continuous or combined monitoring systems should be used. These technologies may improve detection compared to visual assessment by reducing human bias. Behavioral changes in particular may be detected through these means, with changes indicating potential health abnormalities in the individual cattle. One such behavior that changes during incidences of discomfort is lying laterality, or the preference of lying on one side over the other. Calves infected with the bacterium, Mannheimia haemolytica, spent more time lying on their right side than their left side (7.8 ± 0.3 vs. 6.8 ± 0.3 h/d, P = 0.01) and experienced a mild respiratory infection as indicated by greater rectal temperatures 12 hours post inoculation compared to control calves (41.3 ± 0.3 °C vs 39.2 ± 0.3 °C; P < 0.01) and mean lung lesion scores (7.32 ± 0.39%). Lactating dairy cattle on Croatian dairy farms with unilateral hock injuries spent more time lying on their left side than their right compared to cows with bilateral injuries and uninjured cows (P = 0.02). Changes in lying behavior combined with presence of lung lesions or hock injuries indicate increased discomfort and decreased welfare in calves and cows.

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