Milk yield and survival of Holstein-Friesian dairy cattle after laparoscopic correction of left-displaced abomasum.

The milk yield and survival of 91 Holstein-Friesian dairy cows that had had a left-displaced abomasum (LDA) corrected laparoscopically were compared with those of 193 control cows matched for herd, parity and calving date. Ninety per cent of the LDA treatments were performed within four weeks after calving. The risk of being culled during the whole observational period of at least three years was 1.5 times greater for the LDA cows than for their matched herdmates (P<0.01). The risk of being culled in the current lactation was 1.8 times greater for the LDA cows (P=0.01), but risk of being culled after the next calving following the LDA correction was similar for both groups. For the lactation in which the LDA was corrected, there was no difference in the 305-day milk production of 80 of the LDA cows and 182 of the matched cows; however, the mean interval from calving to first service during the same lactation was longer for the LDA cows (115 v 98 days) and the mean calving interval was also longer (451 v 418 days).