Monensin and the prevention of tryptophan-induced acute bovine pulmonary edema and emphysema.
3-Methylindole, a ruminal fermentation product of tryptophan, induces acute pulmonary edema and emphysema in cattle, and 3-methylindole is present in the ruminal fluid and blood of cows with a natually occurring form of this disease. Monensin, a polyether antibiotic and widely used feed additive for beef cattle, prevented tryptophan-induced acute bovine pulmonary edema and emphysema. Monensin acted by reducing the ruminal conversion of L-tryptophan to 3-methylindole both in vitro and in vivo. Lasalocid, also a polyether antibiotic, showed similar effects in vitro. These results provide a promising approach to prevention of this major respiratory disease of cattle.
D000818:Animals; D002417:Cattle; D005663:Furans / Q000627:therapeutic use*; D007832:Lasalocid / Q000627:therapeutic use; D008985:Monensin / Q000494:pharmacology / Q000627:therapeutic use*; D011016:Pneumonia, Atypical Interstitial, of Cattle / Q000517:prevention & control*; D012417:Rumen / Q000378:metabolism; D012862:Skatole / Q000378:metabolism; D014364:Tryptophan / Q000378:metabolism
D005663:Furans; D014364:Tryptophan; D008985:Monensin; D012862:Skatole; D007832:Lasalocid