Effect of avilamycin, tylosin and ionophore anticoccidials on Clostridium perfringens enterotoxaemia in chickens

In order to study the prophylactic and metaphylactic effect of antomicrobia l growth promoters and ionophorous anticoccidials on the incidence of CI. p erfringens enterotoxaemia in chickens, experimental attempts were performed with 675 chickens in 27 trials. The birds were intraduodenally infected wi th CI. perfringens type A (ATCC 3624). The following antimicrobial growth p romoters and ionophore anticoccidials were used either on their own or in c ombination: avilamycin, narasin, monensin and tylosin. While infected and non-medicated trials showed an average incubation period of 1 week, clinical symptoms occurred 2-4 days later in infected and medic ated birds. Avilamycin medicated birds had the longest incubation period. I n the infected and non-medicated trials, a mortality rate of 16 %-36 % was noted within 3 weeks post infection. The avilamycin trials showed a mortali ty rate of 0-8 % (0-2 birds died) and the narasin and monensin a mortality rate of 0-8 %, respectively. In the combination groups (monensin + avilamyc in or narasin + avilamycin), the mortality rate ranged from 0 to 4 %. Tylos in showed a very good metaphylactic/therapeutic effect against CI. perfring ens enterotoxaemia. Following infection, medicated birds showed a significantly better bodyweig ht gain than the chickens, whose feeds had not been supplemented. From epid emiological point of view, the systematic prevention of coccidiosis is a ke y in the control of CI. perfringens enterotoxaemia in chickens.