Thirty-eight lactating dairy cows including 6 ruminally cannulated cows were used in a feeding study to assess effects of feed sources that differed in dietary nonfiber carbohydrate (NFC) composition and ruminal degradability of dietary protein (RDP) on production, ruminal, and plasma measures. The design was a partially balanced, incomplete Latin square with three 21-d periods and a 3 x 2 fact...

Homocitrulline arises from the reaction between cyanate and the epsilon-amino group of lysine residues; in milk, cyanate derives from heat-induced urea breakdown. Since homocitrulline levels were unknown in heated milk, its formation was studied in the temperature range 100-150 degrees C. Firstly, an analysis method based on ion-exchange chromatography using an amino acid analyser was developed...

The objective of this study was to evaluate the effect of ruminally protected amino acids (RPAAs) and ruminally protected fat (RPF) supplementation on ruminal fermentation characteristics (in vitro) and milk yield and milk composition (in vivo). Fourteen mid-lactating Holstein dairy cows (mean weight 653±62.59 kg) were divided into two groups according to mean milk yield and number of days of p...

Four multiparous lactating Holstein cows fitted with rumen cannulae were fed diets varying in the amount and source of rumen-degradable carbohydrates (starch vs. sucrose) to examine their effects on rumen fermentation, nitrogen metabolism and lactation performance. A 4×4 Latin square with four diets and four periods of 28 days each was employed. Corn starch and sucrose were added to diets and c...

Nitrogen is the most important essential nutrient that plays a major role in achieving maximum crop yield in agriculture. Therefore, nitrogen fertilizers such as ammonium sulfate and urea have been extensively used in modern agriculture. These fertilizers are generally oxidized to nitrate via nitrite by nitrifying microorganisms in the agricultural field (4, 10, 11). The serious environmental p...

Adequate supply of amino acids can improve the efficiency nitrogen use. Casein is predominant milk protein, and its supplementation protein synthesis efficiency. We evaluated effects post-ruminal casein on yield composition whole-body deposition. Two ruminally cannulated Holstein dairy cows (599 kg) were used in a switch-back design, treatments an abomasal infusion 0 or 400 g/day casein. Cows f...

The use of new sources by-pass protein in the cow diets to optimize milk production and herd reproduction performance indicators modern economic conditions is relevant. article presents data on a concentrate containing plant animal components its effect quality obtained, state rumen bacterial community indicators. both 1.0 kg 1.5 kg/head/day contributed improving increasing yield dry matter cow...