반추가축영양 : 젖소우유중 요소태질소 함량에 따른 사료급여의 최적화가 번식력에 미치는 영향 = Ruminant Nutrition : The Effect of Optimum Feeding Based on Milk Urea Nitrogen by Azotest on Reproductivity of Holstein Dairy Cows

다국어 초록 (Multilingual Abstract)

This experiment was conducted to determine the effect of controlled feeding of dietary crude protein and energy from 3 different MUN(milk urea nitrogen) contents(Azotestⓡ rank Ⅳ, V and VI) before feeding trial to the MUN content(Azotest rank Ⅳ) immediately after feeding trial on the BUN(blood urea nitrogen) content, milk yield and reproduction efficiency. BUN(blood urea nitrogen) was decreased to the adequate content(12-18㎎/㎗) when diets were adjusted from Azotest rank Ⅳ, V and VI before trial to Azotest rank Ⅳ immediately after trial, respectively. As a result, fertility rate was considerably increased after controlled feeding, especially improved from about 30% by second service before feeding control to l00% at the first service in the Azotest rank V and at the second service in the Azotest rank VI after feeding control, respectively. In addition, average open day became shorter after controlled feeding(151.3 vs 87.5d). However, milk yield was not different between before and after controlled feeding.