Animal behaviour in the sub-tropics. I. Heat tolerance in relation to grazing behaviour in sheep.

Abstract

Thirty ewes of the breeds Ossimi indigenous, Texel, Caucasian Merino and Fleisch Merino were studied in newly reclaimed desert in Egypt. Body temp., respiration rate and skin temp. of each ewe were measured four times daily, i.e. before it left the shed, on arrival at the pasture 5 km. away, before leaving the pasture, and finally when it returned to the shed. The air temp. was recorded at the time of each test. The most pronounced breed difference was in the respiration rate. The initial values at morning were only 16 respirations a minute in both Ossimi and Caucasian Merino, whereas the Texel and the Fleisch Merino had respectively four and five times this value. Walking to the pasture and grazing activity had different effects on the cardiorespiratory reactions of the different breeds, and Ossimi was the least affected. (AS). (Abstract retrieved from CAB Abstracts by CABI’s permission)