Effect of stage of lactation and breed on dairy cows' acceptance of fostercalves

We examined at what time after separation from their own calf, dairy cows b est accept foster calves, and if there are differences between two breeds i n their willingness to accept foster calves. In total 48 cows, 24 Swedish R ed and White (SRW) and 24 Swedish Holstein-Friesian (SHF) were used. They w ere tested at four different times after separation from their own calf: (1 ) directly; (2) 4 days; (3) 26 days; and (4) 178 days after (n = 6 cows/tre atment). Twelve groups of four calves in each, two calves of each breed, we re used to test the cows. Each calf group was used to test four cows of the same breed from different times after separation in a random balanced orde r during 29 h. Behaviours were recorded with direct observations for the fi rst and last 2 h using 1-0 sampling at 3 min intervals. The behaviours were tested statistically with analysis of variance. There was no significant e ffect of the four different times after separation. SRW cows sniffed the ca lves significantly more than SHF cows during both observation periods (P < 0.05). Two cows had to be tied during the 29 h and were therefore excluded from further analysis, Seven cows (two SHF, five SRW) were so aggressive th at they had to be tied between observation periods, but there was not a sig nificant difference in aggressive behaviour between the two breeds. Cows th at were tied between observation periods butted the calves more during the first observation than cows that were kept loose (P < 0.001). Calves suckle d less on cows that were tested 178 days after separation than on cows that were tested directly or 4 days after separation from their own calf (P < 0 .05). The SRW calves suckled and tried to suckle the cows more than the SHF calves (P < 0.001, < 0.05). It is concluded that dairy cows of both breeds and from different stages of lactation accept alien foster calves equally well. (C) 2001 Elsevier Science B.V, All rights reserved.