Effect of body condition at calving on the health and performance of dairy cows

Abstract

ABSTRACTTwo groups of nine British Friesian cows were fed from about 32 weeks before calving to achieve condition scores at calving of 2·5 (thin) and 4 (fat). For 10 weeks after calving all cows were offered 7 kg hay daily in four feeds, with concentrates given five times daily according to appetite.During early lactation, the group of fat cows had lower dry-matter intakes and daily milk yields and yielded less milk protein and lactose than the group of thin cows. The mean yield of milk over the whole lactation was 500 kg less in the fat cows but the difference was not significant. The fat cows lost 48 kg body weight and 1·20 units condition score during early lactation compared with 27 kg body weight and 0·52 units condition score in the thin cows. No difference in reproductive performance was found between the two groups but significantly more cases of disease occurred in the fat cows than in the thin cows.It is concluded that cows that are fat at calving eat less than thin cows, give the same or less milk than thin cows, mobolize more body tissue and lose more weight after calving than thin cows and suffer more disease.