HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Glenn, B. P. Articles by Goering, H. K. Search for Related Content PubMed PubMed Citation Articles by Glenn, B. P. Articles by Goering, H. K.

Effects of Diet Nitrogen and Forage Nitrogen Insolubility on Performance of Cows in Early Lactation¹

Ruminant Nutrition Laboratory, Beltsville Agricultural Research Center, US Department of Agriculture, Agriculture, Research Service, Beltsville, MD 20705

ABSTRACT

Thirty-six Holsteins were allotted at parturition to six treatments to measure effects of diet nitrogen and increased insolubility of silage nitrogen on performance and ruminal, plasma, and milk constituents during the first 100 d of lactation. Diets contained 40% concentrate and 60% silage in dry matter. The six silage treatments were 1) untreated corn silage (low nitrogen); 2) untreated corn silage and untreated alfalfa silage (1:1); 3) untreated corn silage and formaldehyde and formic acid-treated alfalfa silage (1:1); 4) ammonia-treated corn silage (low nitrogen); 5) treated corn silage and untreated alfalfa silage (1:1); or 6) treated corn silage and treated alfalfa silage (1:1). Diets containing ammonia-treated corn silage had higher hot water-insoluble nitrogen and diets containing formaldehyde and formic acid-treated alfalfa had higher autoclaved rumen fluid-insoluble and hot water-insoluble nitrogen that their respective untreated silage diets. Dry matter intake, daily yields of milk and its constituents, ruminal NH₃ nitrogen, and plasma urea nitrogen were lower for cows consuming low nitrogen diets containing only corn silage compared with cows consuming high nitrogen diets containing alfalfa. Dry matter intake and milk protein yields were greater for cows consuming treated alfalfa compared with untreated alfalfa in the diet. Daily 4% fat-corrected milk yields tended to be higher for diets containing treated alfalfa than untreated alfalfa. Cows fed diets containing NH₃-treated corn silage had similar milk, fat, and protein yields compared with diets containing untreated corn silage and urea in the concentrate.

¹ Mention of a trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the US Department of Agriculture and does not imply its approval to the exclusion of other products that may be suitable.