Influence of the fleece on thermal homeostasis and on body condition in Comisana ewe lambs

The aim of this study was to determine the effect of shearing on the thermal homeostasis of Comisana ewe lambs during summer. The rectal temperature, heart rate, respiration rate, average arterial pressure, percentage of oxygen saturation in blood (SpO2%), haematocrit value, live weight and body condition score in two similar groups of 9-month-old ewe lambs were compared. Immediately after initial measurements (day 0), ewe lambs in one group were shorn while those in the other group were left unshorn. All the measurements taken on day 0 were repeated after 20, 40, 60 and 80 days from the beginning of the experiment. Rectal temperature and arterial pressure of ewe lambs did not differ (P > 0.05) on any of the examination days. Respiration and heart rates were higher (P < 0.05) in the unshorn group of ewe lambs. The haematocrit value and the SpO 2 % were always higher (P < 0.05) in the shorn group. The live weight of ewe lambs increased in both groups, while the body condition score of the lambs at the end of the trial period was lower (P < 0.05) in comparison to the initial score. Shearing the fleece of ewe lambs resulted in a lower heat stress during the summer while thermal homeostasis was not influenced. fleece / dairy ewe lamb / shearing / summer / thermal homeostasis

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