title: Quarantine treatment of sheep with monepantel--rapidity of fecal egg count reduction.
abstract: In the presence of multiple anthelmintic resistance, effective quarantine treatment of sheep entering a farm has become a crucial tool in nematode management. In the present work, the use of the amino-acetonitrile derivative, monepantel as a quarantine treatment was investigated. Of special interest was the rapidity of decrease in fecal egg counts (FEC) compared to other anthelmintics used in sheep. In three different studies, sheep were either infected with Haemonchus contortus of known resistance status or with a panel of susceptible and multi-resistant gastro-intestinal nematodes. Fecal egg counts were determined from several hours up to 14 days after treatment with monepantel, benzimidazoles, levamisole, macrocyclic lactones or combinations of the latter three classes. The treatment of susceptible isolates with effective anthelmintics, either as single or combined applications caused a reduction of FEC to 0 within 3-4 days. The status of the resistant nematodes could be confirmed, as treatment with the affected classical anthelmintics never resulted in complete absence of parasite eggs in all samples analyzed. In the case of multi-resistant isolates, only monepantel was able to stop egg excretion, while all other treatments resulted in only a partial reduction of FEC. The resistance status of the nematodes did not influence the rapid decline of egg counts after treatment with monepantel.
authors.affiliation: Novartis Centre de Recherche Santé Animale SA, CH-1566 St-Aubin, Switzerland. heinz.sager@novartis.com
authors.forename: Heinz
authors.initials: H
authors.lastname: Sager
authors.forename: Peter
authors.initials: P
authors.lastname: Rolfe
authors.forename: Guenther
authors.initials: G
authors.lastname: Strehlau
authors.forename: Brooke
authors.initials: B
authors.lastname: Allan
authors.forename: Ronald
authors.initials: R
authors.lastname: Kaminsky
authors.forename: Barry
authors.initials: B
authors.lastname: Hosking
mesh_terms: D000607:Aminoacetonitrile / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D001315:Australia / Q000453:epidemiology; D005243:Feces / Q000469:parasitology; D005767:Gastrointestinal Diseases / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary; D009349:Nematode Infections / Q000188:drug therapy / Q000662:veterinary*; D010270:Parasite Egg Count; D011790:Quarantine / Q000662:veterinary*; D012756:Sheep; D012757:Sheep Diseases / Q000188:drug therapy* / Q000453:epidemiology / Q000469:parasitology; D013557:Switzerland / Q000453:epidemiology
chemical_list: D000871:Anthelmintics; D000607:Aminoacetonitrile; C533978:monepantel