PRELIMINARY-STUDY ON THE EFFECT OF SIZE OF INDIVIDUAL STALL ON THE BEHAVIORAL AND IMMUNE-REACTIONS OF DAIRY CALVES

Ten Italian Friesian female calves were housed in individual stalls of two different dimensions (0.73 m x 1.21 m vs 1.00 m x 1.50 m) during the Ist month of life in order to evaluate the effect of space on the welfare of dairy calves. Behavioural observations were made on d 2 to 3 (period 1) and on d 28 to 29 (period 2) during daylight using a time -lapse video recording system. At 10, 20, and 30 d, blood samples were taken and analysed with phytohemagglutinin stimulation to determine l ymphocyte proliferation. During the second period, the calves in large stall spent more time lying (P<0.05) and grooming (P<0.001), and the calves in small stalls exhibited more time searching for feed (P<0.001 ). Lymphocyte proliferation was statistically lower in calves housed i n smaller stalls (P<0.01). Moreover, lymphocyte proliferation was nega tively correlated with time spent searching for feed (P<0.01).