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 Muir, L. A. Articles by Smith, G. E. Search for Related Content PubMed PubMed Citation Articles by Muir, L. A. Articles by Smith, G. E.

Prevention of Induced Lactic Acidosis in Cattle by Thiopeptin

Merck Institute for Therapeutic Research^1,2,, Rahway, NJ 07065

Abstract

Fistulated bull calves that were given ground wheat intraruminally at 40 g/kg body weight developed both ruminal and systemic lactic acidosis. Rumen lactate increased from less than 1 to over 100 µmoles/ml by 6 hr after wheat administration. Plasma lactate increased and blood base excess decreased after elevation of rumen lactate, with calves dying when plasma lactate and blood base excess reached 36 µmoles/ml and -22 meq/liter, respectively. Steers, which were abruptly shifted to a micronized milo diet, developed ruminal, but not systemic, lactic acidosis. Rumen lactate increased from less than 1 to over 150 µmoles/ml by 16 hr after milo feeding. However, plasma lactate and blood base excess remained in the normal range. Thiopeptin, a sulfur-containing peptide antibiotic, prevented lactic acidosis in both cases by reducing the production of ruminal lactic acid. Fistulated calves given a single dose of thiopeptin at .75 or 1.50 mg/kg body weight and steers given thiopeptin at 11 or 22 ppm in the feed had 80 and 70% less rumen lactate, respectively, than controls. In addition, in both studies thiopeptin allowed "normal" rumen fermentation to proceed, as indicated by dramatic increases in total volatile fatty acids. Forty Angus steers were tested for the effect of thiopeptin on performance following a lactic acidosis challenge. Steers that were abruptly shifted to micronized milo developed ruminal lactic acidosis. Thiopeptin at 11 ppm in the feed prevented lactic acidosis and improved (P<.10) weight gain, feed intake and efficiency of feed utilization at 2 weeks. At 4 weeks, steers fed thiopeptin were still performing better than controls, but the differences were not statistically significant.

¹ Dept. of Anim. Nutr. and Physiol.

² The authors express their appreciation to Walter O'Shanny for his help in the care of experimental animals and the collection of samples.