Occurrence of ketone bodies in the urine of cows during the first three months after calving and their association with milk yield
Abstract. The aim of the study was to assess the effect of lactation number, month after calving, body condition at calving, milk yield and feeding season on the frequency and intensity of occurrence of ketone bodies in the urine during the first trimester after calving of Polish Holstein-Friesian cows cows with average annual milk yield of about 7,000 kg. It was also evaluated how the presence of ketone bodies in the urine of cows was associated with their milk production and the course of lactation. 479 urine samples were collected from the cows. The samples were tested using KRULAB test strips. The influence of the presence of ketone bodies on milk yield in 150 lactations and in 1,797 milk samples was also evaluated. It was found that 36.2 % of urine samples contained ketone bodies that could indicate various forms of ketosis. The frequency and intensity of the occurrence of ketone bodies in the urine was significantly influenced by the cows' body condition at calving, milk yield during standard lactation, the day the urine samples were collected and feeding season. The presence of ketones in the urine had little effect on milk yield in standard and complete lactations. Cows whose urine contained ketone bodies had significantly higher daily milk yield up to the sixth month of lactation. This could indicate that cows with high production potential are more susceptible to ketosis. The occurrence of ketones in the urine had a negative effect on the lactation curves of the cows tested.