This study aimed to evaluate urea excretion, nitrogen balance and microbial protein synthesis in lactating goats fed with diets containing different protein sources in the concentrate (soybean meal, cottonseed meal, aerial part of cassava hay and leucaena hay). Four Alpine goats whose mean body weight was 42.6±6.1 kg at the beginning of the experiment, a mean lactation period of 94.0±9.0 days a...

The study was conducted to assess the effect of milk production, parity, stage of lactation, season and individual milk components themselves on milk urea nitrogen (MUN) concentration and other milk components of 3,219 Holstein dairy cows in Korean dairy farms. The MUN concentrations in Korean dairy cows were estimated to 16.68±5.87 mg/dl. Milk yield was negatively correlated with fat and prote...

In dairy cows, dietary crude protein (CP) that can is not captured as milk protein is largely excreted as N in manure. Of course, some protein-N is retained for growth in first and second lactation animals and in the calf and fetal tissues during pregnancy; however, these amounts are small relative to the proportion of absorbed N going into milk. Cows and other mammals convert N from absorbed a...

The present experiment aimed to evaluate the effect of HMBi on the production performance and metabolism in dairy cows. Thirty multiparous Holstein dairy cows under similar conditions were randomly assigned to three dietary treatments; i) Control, a basal diet; ii) T1, a basal diet plus HMBi (0 g prepartum and 18 g postpartum); and iii) T2, a basal diet plus HMBi (10 g prepartum and 18 g postpa...

Four treatments were assigned to determine the effects of dietary potential digestible fiber (pdF) and crude protein (CP) levels in mid lactating Holstein cows on milk production and nitrogen efficiency. Sixteen primiparous (n=8) and multiparous (n=8) Holstein cows (body weight (BW)=546±72 kg; days in milk (DIM)=118±50 day) were allocated to one of four diets in balanced randomized complete des...

Twenty-four multiparous Holstein cows were used in six 4×4 Latin squares with 28day periods to determine inclusion rates for wet corn gluten feed (WCGF) in diets for lactating dairy cows. Cows were housed in a tie-stall barn and fed diets to meet or exceed NRC (1989) nutrient requirements. Experimental treatments were 1) control, 2) WCGF constituting 20%, 3) WCGF constituting 27.5%, and 4) WCGF...

To determine the effect of Dietary Crude Protein (DCP) on milk production and protein metabolism, a two group pre/post experimental design was used. The CP level in the ration fed to the two groups (high, low) of lactating dairy cows was increased by 2% for a period of 21 days. Data from each group was collected regarding manure scores, milk fat, milk protein, Milk Urea Nitrogen (MUN) and overa...