Associations between open-field behaviour and stress-induced hyperthermia in two breeds of sheep

Publication Type:
 Journal Article
Year of Publication:
 2011
Authors:
 C. Pedernera-Romano, J.L Ruiz de la Torre, L. Badiella, X. Manteca
Publication/Journal:
 Animal Welfare
Keywords:
 , , , , ,
ISBN:
 0962-7286
Abstract:

In sheep (Ovis aries) and other farm animals, routine husbandry procedures can cause negative emotions, such as fear, which are
generally considered to reduce animal welfare. The open-field test (OFT) is the most widely used test to measure fearfulness in animals.
The induction of psychological stress is often accompanied by an elevation of core body temperature, referred as stress-induced hyperthermia
(SIH) and both OFT and SIH were used in this study to measure fearfulness in sheep: the aim being to examine associations
between behaviour in the OFT and the SIH response, using data from two breeds of sheep tested repeatedly over time. Twenty-four
ewes from two breeds, Lacaune and Ripollesa, were tested for 10 min with all behaviours recorded throughout. Rectal temperature
was measured immediately prior to the start of the test (T1) and 10 min after its completion (T2). SIH was measured as the difference
between T2 and T1. Sheep were tested over three periods of three experimental days each. Ewes of both breeds showed consistent
changes in behaviour in the OFT and a clear SIH response. Bleats and visits to the water bucket showed a clear pattern between
rounds. Differences between T1 and T2 were found, T2 was higher than T1 suggesting that exposure to a novel arena caused SIH.
Breed differences were found whereby T2 was 0.12ºC higher in Ripollesa than Lacaune. These findings have implications for selection
programmes, creating the possibility of selecting less fearful animals that will cope better with handling procedures that may induce
fear. Further, they also demonstrate the importance of using both behavioural and physiological variables to evaluate fear.

Links:

Back to Resources