Urine volume of non-lactating dairy cows in late gestation fed forage based diets in winter

摘要

Quantitative information on urine volume of dairy cows fed winter forages is required to accurately evaluate nitrate leaching risks on these diets. Thirty-two Friesian x Jersey non-lactating, pregnant dairy cows were fed either 10 kg DM of fodder beet with 5.6 kg DM of ryegrass baleage or 16.4 kg DM of kale with 6.4 kg of oat silage. Cows were fitted with a urine meter for 24 to 72 hours to record the frequency and volume of urine events. Daily urine volume (28 ± 3 L/cow/day), frequency (9 ± 0.89 events/cow/day), and event volume (3.2 ± 0.3 L/event) were not significantly different between fodder beet and kale treatments. This was despite respective differences in total apparent water (51 vs. 70 L/cow/day, ± 2, P<0.001) and nitrogen (N) intake (231vs. 488 gN/cow/ day, ± 9.4, PO.001). In this study, water consumption and N intake did not appear to be linked with urine volume of dairy cows when two different forage diets were compared.