Abstract

Prepartum milk leakage happens in some pregnant dairy cows close to calving. It has been hypothesized that low blood Ca is a cause of this event. In order to investigate the possible reason(s) of milk leakage 137 multiparous pregnant Holstein cows were enrolled in the experiment and categorized by the presence (72 heads; LEAK) or lack (65 heads; CON) of milk leakage prior to calving. The concentrations of Ca, P and the length of teat were measured for all cows. Data showed that Ca concentration was not different between LEAK (7.90 mg/dL) and CON (7.99 mg/dL) cows (P > 0.05). Moreover, neither P concentration (4.62 versus 4.54 mg/dL; P > 0.05) nor teat length (4.28 versus 4.10 cm; P > 0.05) was LEAK or CON situation, respectively. Milk yield was greater (P < 0.05) for LEAK (53.6 kg/d) compared to CON (50.1 kg/d) cows through four months in milk. The leakage did not affect the odds of postpartum disorders such as retained placenta, metritis, mastitis, displaced abomasum or lameness occurrence (P > 0.05). The current results show that hypocalcemia is not a reason for observed prepartum leakage and that LEAK cows produce more milk in the subsequent lactation period.