|DJEMAI, SAMIR - University Of Constantine 1|
|MEKROUD, ABDESLEM - University Of Constantine 1|
Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/1/2016
Publication Date: 7/15/2016
Citation: Djemai, S., Mekroud, A., Jenkins, M.C. 2016. Evaluation of ionophore sensitivity of Eimeria acervulina and Eimeria maxima isolated from the Algerian Jijel province poultry farms. Veterinary Parasitology. 224:77-81.
Interpretive Summary: Avian coccidiosis is an intestinal disease of poultry caused by protozoa in the genus Eimeria. Coccidiosis outbreaks are controlled by either medication of poultry feed with anti-coccidial drugs or vaccination of day-old chicks with low doses of live Eimeria oocysts. Vaccination has become more popular in controlling this disease because of the increasing resistance of Eimeria to anticoccidial drugs. There have been very few studies outside of major poultry producting countries demonstrating a relationship between use of particular anticoccidial drugs and resistance to these compounds. The present study examined the sensitivity of E. acervulina and E. maxima on poultry farms in rural Algeria. The data indicates that continuous use of ionophore drugs has led to drug resistance of Eimeria. Moreover cross-resistance to different types of ionophore drugs suggests that switching between different drug classes may not be an effective control strategy. These findings provide further support for the use of live Eimeria oocyst vaccines to control avian coccidiosis, especially after years of continuous drug usage.
Technical Abstract: The present study represents the first description of ionophore resistance in Eimeria recovered from commercial Algerian (Jijel-Algeria) broiler farms. Microscopy and ITS1 PCR revealed only 2 Eimeria species present in litter from these farms- namely E. acervulina and E. maxima. A pool of these isolates were evaluated in broiler chickens (Cobb 500) for sensitivity to 5 anticoccidial compounds- diclazuril (1 ppm), lasalocid (125 ppm), monensin (125 ppm), narasin (70 ppm) and salinomycin (60 ppm). As indicated by anticoccidial sensitivity profiles based on lesion scores and anticoccidial index (ACI), complete resistance to monensin and narasin, partial resistance to salinomycin and lasalocid, and complete sensitivity to diclazuril was observed. While lack of sensitivity to monensin is not surprising given its use for years as the sole anticoccidial compound, the resistance to monother (narasin) and polyether (lasalocid) ionophores suggests that cross-resistance has developed in a segment of the Eimeria population. The fairly uniform Eimeria species composition among all poultry farms suggests that E. acervulina and E. maxima more rapidly develop resistance to ionophore drugs.