Avoparcin and Monensin Effects on Digestive Function in Cows Fed a High Forage Diet

✍ Scribed by Haïmoud, Djamila Ali; Bayourthe, Corine; Moncoulon, Raymond; Vernay, Michèle

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 715 KB
• Volume: 70
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/(sici)1097-0010(199602)70:2<181::aid-jsfa480>3.0.co;2-7

✦ Synopsis

Three non-lactating cows with ruminal, duodenal, and ileal cannulas were used in a 3 x 3 Latin square design to evaluate the effect of oral avoparcin and monensin on fibre, starch, and nitrogen (N) digestion. Cows were fed three high forage diets; the control diet had no additive, and the others contained 33 mg kg-' DM of either avoparcin or monensin. Neither additive affected apparent total tract digestibilities of organic matter, fibre, starch or N. Avoparcin and monensin reduced the ruminal breakdown of fibre, starch and dietary N. Efficiency of bacterial N synthesis was unchanged, and passage of bacterial N to the small intestine was not modified. Compared with the control, additives caused a greater proportion of feed starch, N, and total amino acid to be digested in the small intestine than in the rumen. Diets containing avoparcin or monensin increased availability of total essential amino acid in the small intestine compared with that of control diets. Post-ruminal digestion of fibre was greater for diets supplemented with antibiotics, because the cows compensated digestion in the lower forestomach.