caa a22 4500 445340592 CHVBK 20180317142811.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s00436-011-2410-8 doi (NATIONALLICENCE)springer-10.1007/s00436-011-2410-8 The Efficacy of Trichlorphon and Naphthalophos against Multiple Anthelmintic-Resistant Nematodes of Naturally Infected Sheep in Argentina [Elektronische Daten] [César Fiel, Maricel Guzmán, Pedro Steffan, Edgardo Rodriguez, Olegario Prieto, Chandra Bhushan] An anthelmintic efficacy trial was conducted in sheep harbouring anthelmintic-resistant worms in Argentina. Seventy lambs were selected from a flock that had been grazed on pastures infected with trichostrongyles previously shown to be resistant to the main anthelmintic groups. Lambs were allocated to comparable groups of ten animals each and treated with trichlorphon (50mg/kg body weight (b.w.) orally); naphthalophos (50mg/kg b.w. orally); ivermectin (0.2mg/kg b.w. subcutaneously); fenbendazole (5mg/kg b.w. orally); levamisole (8mg/kg b.w. subcutaneously) and closantel (10mg/kg b.w. orally). There was also an untreated group. The dose selection was based on manufacturer's recommendations. Faecal samples were collected 0 and 10days post treatment to estimate efficacy (faecal egg count reduction). Six animals from each group were necropsied at day 10 for enumeration/identification of worms from the abomasum, small and large intestines to determine the absolute efficacy of each agent (controlled efficacy test). Trichlorphon and naphthalophos were effective (> 99 %) against Haemonchus contortus (p < 0.05). Naphthalophos also showed efficacy against Trichostrongylus axei (99.3 %), Teladorsagia circumcincta (97.8 %), Trichostrongylus colubriformis (99.2 %), Cooperia punctata/curticei/pectinata (90.4 %), Nematodirus spathiger (89.2 %) and Oesophagostomum venulosum/columbianum (93.7 %). Fenbendazole and levamisole showed efficacy (> 95 %) against all nematodes except T. colubriformis. The efficacy of ivermectin was low against H. contortus (23 %) and Cooperia spp. (46.3 %). Closantel showed low efficacy against T. axei (64.4 %), H. contortus (80.6 %) and T. colubriformis (59.5 %). When anthelmintic resistance is widespread, trichlorphon treatment is appropriate if H. contortus is present; however, naphthalophos represents an effective therapeutic alternative for incorporation into worm control programmes. Springer-Verlag, 2011 Fiel César Área de Parasitología, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut Guzmán Maricel Área de Parasitología, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut Steffan Pedro Área de Parasitología, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut Rodriguez Edgardo Área de Bioestadística, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut Prieto Olegario Bayer HealthCare, Animal Health Division, Munro, Buenos Aires, Argentina aut Bhushan Chandra Bayer HealthCare, Animal Health Division, Monheim, Germany aut Parasitology Research Springer-Verlag 109(2011-08-01), 139-148 0932-0113 109<139 2011 109 436 https://doi.org/10.1007/s00436-011-2410-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00436-011-2410-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Fiel César Área de Parasitología, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut NATIONALLICENCE 700 1- Guzmán Maricel Área de Parasitología, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut NATIONALLICENCE 700 1- Steffan Pedro Área de Parasitología, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut NATIONALLICENCE 700 1- Rodriguez Edgardo Área de Bioestadística, Facultad de Ciencias Veterinarias, UNCPBA, Campus Universitario, Tandil, Argentina aut NATIONALLICENCE 700 1- Prieto Olegario Bayer HealthCare, Animal Health Division, Munro, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Bhushan Chandra Bayer HealthCare, Animal Health Division, Monheim, Germany aut NATIONALLICENCE 773 0- Parasitology Research Springer-Verlag 109(2011-08-01), 139-148 0932-0113 109<139 2011 109 436 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer