Monday, May 12, 2008

Tetracycline-resistant abortion

Campylobacter infection (vibriois) is one of the major causes of ovine abortions worldwide. Historically, Campylobacter fetus was the major cause of Campylobacter-associated abortion in sheep; however, there has been a trend that Campylobacter jejuni is increasingly associated with sheep abortion.

aborted fetus (image by AASRP)Campyolobacter isolates were obtained from multiple lambing seasons on different farms in Iowa, Idaho, South Dakota, and California. It was found that C. jejuni has replaced C. fetus as the predominant Campylobacter species causing sheep abortion in the U.S.

All of the 74 isolates were susceptible to tilmicosin, florfenicol, tulathromycin and enrofloxacin, and 97% were sensitive to tylosin. However, all were resistant to tetracylinces, the only abtibiotics currently approved in the U.S. for treatment of Campylobacter abortion in sheep.

The findings suggest that feeding tetracycline for the prevention of Campylobacter abortions is ineffective and other antibotics, instead of tetracyclines, should be used for the treatment of sheep abortions caused by this organism.

A single tetracycline-resistant C. jejuni clone has emerged as the major cause of Campylobacter-associated sheep abortion in the U.S.

Source: AASRP Newsletter, Wool & Wattles, January-March 2008.

Abortion in sheep [PDF, PPT]
Campylobacter Abortion in Ewes - NADIS