Lactational Evaluation of Ruminally Protected Methionine in Diets Containing Extruded Soybeans and Urea

<p>Research by others indicated that the addition of urea to diets containing extruded soybeans increased bacterial N and lysine flow· from dual flow continuous culture fermenters. This dietary regime may create a methionine deficiency which could be prevented with ruminally protected methionine. This theory was tested using 28 high producing Holstein cow (14 primiparous and 14 multiparous) fed a concentrate mix containing extruded soybeans and urea with or without 15 g of added DL-methionine supplied as 50 g of ruminally protected methionine product. Treatment periods started wk 4 postpartum and continued through wk 16 with milk production and composition during wk 3 postpartum used as covariates. Cows were fed a 16.0% crude protein total mixed diet of (dry matter basis) 40% corn silage, 10% alfalfa hay, and 50% concentrate mix. Yields of milk (33.8 and 35.0 kg/d) and fat corrected milk (26. 8 and 28. 4 kg/d) were similar (P>. 05), although numerically highest when fed protected methionine. Percentages of fat (2.71 and 2.79), protein (3.02 and 2.98), and solids-not-fat (8.64 and 8.54) were similar (P>.05). Dry matter intakes (20.8 and 19.2 kg/d) were similar between groups (P>.05). Arterial concentrations of methionine were increased by supplemental methionine. Transfer efficiency of amino acids indicated that methionine was changed from first to second limiting by methionine supplementation.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis - University Access Only

Discipline thesis:degree_discipline

Dairy Science

Year dc:date.available

1989

Author dc:creator

• Munneke, Ronald L.

Contributors dc:contributor

• David J. Schingoethe

• Dairy Science

Statement dc:rights

• <p>In Copyright - Non-Commercial Use Permitted<br /><a href="http://rightsstatements.org/vocab/InC-NC/1.0/">http://rightsstatements.org/vocab/InC-NC/1.0/</a></p>

Language dc:language

en

Repository record dc:identifier

https://openprairie.sdstate.edu/etd/1522

OAI identifier oai:identifier

oai:openprairie.sdstate.edu:etd-2492