Incidence of production diseases and other health problems in a group of dairy herds in England.

The incidence of major production diseases and other health problems was investigated in 90 Friesian/Holstein dairy herds in England (average size 152 cows) for cows calving during 12 months in 1992-1993. The mean incidence of mastitis was 33.2 cases per 100 cows, and it affected 20.6 per cent of the herd with 1.6 cases for each affected cow. On average, 17.4 per cent of the cows suffered from lameness, with 1.4 cases per affected cow and a total of 24.0 cases per 100 cows. Cows treated for oestrus-not-observed totalled 33.6 per cent, with 46.4 treatments per 100 cows. The incidence of milk fever was 7.7 cases per 100 cows. Retained fetal membranes affected 3.6 per cent of cows. Vulval discharge affected 15 per cent of the average herd with 1.4 treatments per affected cow and a total of 21.2 treatments per 100 cows. The mean incidence of twinning was 4.1 per cent. Calf mortality claimed 7.8 calves per 100 calves born. The average number of cows given aid at calving was 8.7 per 100 cows calving.