Susceptibility to disease in the dairy cow and its relationship with occurrences of other diseases in the current of preceding lactation

Abstract

The association between occurrences of pairs of diseases (hypocalcaemia, ketosis, hypomagnesaemia, dystocia, retained placenta, endometritis, mastitis and lameness) was studied in 2109 lactations over 6 years in 894 British Friesian, Ayrshire and Holstein crossbred cows. The recurrence of disease in 1215 pairs of consecutive lactations was also examined. Cows with ketosis or hypocalcaemia in one lactation were twice as likely to have hypocalcaemia in the next, and the occurrence of ketosis in consecutive lactations was also related. The proportions of cows with mastitis were 0.38 and 0.23 depending on whether the cow had or did not have mastitis in the preceding lactation, and cows with lameness showed similar increased probabilities of the same lesion recurring in the next lactation. In contrast, cows with retained placenta, dystocia or endometritis in one lactation showed no increased likelihood of having the same disease in the next. As anticipated, within lactations, the occurrence of endometritis was strongly associated with dystocia and retained placenta. Endometritis was also linked with a two-fold increase in the incidence of ketosis and susceptibility to interdigital cleft lesions. Hypocalcaemia and ketosis occurred three times more often during lactations in which hypomagnesaemia also occurred, but occurrences of mastitis appeared to be generally unrelated to other diseases.