title: Anthelmintic efficacy of an oral formulation of Aurixazol against gastrointestinal nematodes of naturally and experimentally infected sheep.
abstract: As a result of the need to develop new active principles for the control of endoparasites in ruminants, the present in vivo study evaluated a formulation containing 24% Aurixazol (48 mg/kg), a parasiticide molecule based on disophenolate of levamisole. Two experiments were conducted: one evaluating the anthelmintic efficacy of 24% Aurixazol (48 mg/kg) against gastrointestinal nematodes in naturally infected sheep, compared to an association of ivermectin (0.2mg/kg)+albendazole (5.0mg/kg)+levamisole (7.5mg/kg) (IAL), and a second one which evaluated the persistent efficacy of the same formulation against immature stages (L4) and adults of Haemonchus contortus in experimentally infected animals. In experiment I, against H. contortus, the formulation of Aurixazol and the IAL association reached efficacies (arithmetic means) of 99.32% and 96.11%, respectively. For Trichostrongylus colubriformis, the efficacy values were 88.92% and 98.08% for Aurixazol and the IAL association, respectively. Both formulations were totally effective against Oesophagostomum columbianum (100%). The results of the statistical analysis demonstrated that the mean parasitic burden of treated animals was significantly different (P ≤ 0.05) compared to the average number of helminths diagnosed in animals from the control group for H. contortus, T. colubriformis and O. columbianum. Comparing only the treated groups, it was possible to verify that the average number of H. contortus recovered from animals treated with Aurixazol was different (P ≤ 0.05) when compared to the mean amount recovered from sheep treated with the IAL association. When evaluating the prevention of H. contortus infection in experiment II, Aurixazol did not present preventive efficacy. Up until 21 days after treatment the groups treated with Aurixazol contained less adults and L4 of H. contortus (P ≤ 0.05) when compared to the non-medicated control group. However, future studies will be necessary to assess the effectiveness of Aurixazol against nematode strains resistant to levamisole and disophenol, but the efficacy results described in this study allow to state that Aurixazol can, associated with other measures, become an important tool in the control of sheep nematodes.
authors.affiliation: Faculdade de Ciências Agrárias e Veterinárias, UNESP/CPPAR, Via de acesso prof. Paulo Donatto Castellani, s/n CEP:14884-900, Jaboticabal, São Paulo, Brazil.
authors.forename: Claudio Alessandro M
authors.initials: CA
authors.lastname: Sakamoto
authors.forename: Welber Daniel Zanetti
authors.initials: WD
authors.lastname: Lopes
authors.forename: Carolina
authors.initials: C
authors.lastname: Buzzulini
authors.forename: Breno Cayeiro
authors.initials: BC
authors.lastname: Cruz
authors.forename: Gustavo
authors.initials: G
authors.lastname: Felippelli
authors.forename: Roberto Cesar Araújo
authors.initials: RC
authors.lastname: de Lima
authors.forename: Thais Rabelo
authors.initials: TR
authors.lastname: dos Santos
authors.forename: Luis Fernando
authors.initials: LF
authors.lastname: Santana
authors.forename: Rafael Paranhos
authors.initials: RP
authors.lastname: de Mendonça
authors.forename: Vando Edésio
authors.initials: VE
authors.lastname: Soares
authors.forename: Carlos Henrique
authors.initials: CH
authors.lastname: Henrique
authors.forename: Alvimar José
authors.initials: AJ
authors.lastname: da Costa
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D007814:Larva / Q000187:drug effects; D009348:Nematoda; D009349:Nematode Infections / Q000188:drug therapy / Q000517:prevention & control / Q000662:veterinary*; D010270:Parasite Egg Count / Q000662:veterinary; D012756:Sheep; D012757:Sheep Diseases / Q000188:drug therapy* / Q000517:prevention & control
chemical_list: D000871:Anthelmintics
keywords: Aurixazol; Helminths; Preventive efficacy; Resistance; Sheep