title: Retrieval of Trichostrongylus colubriformis infective larvae from grass contaminated in winter and in spring.
abstract: The survival of infective larvae (L3) of Trichostrongylus colubriformis was evaluated on Brachiaria, Coast-cross and Aruana forage grasses. Feces of sheep parasitized exclusively by T. colubriformis were deposited in winter and spring on experimental plots whose grasses were cut at two heights: 5 cm and 30 cm. One, two, four, eight, 12 and 16 weeks after depositing the feces, fecal and forage samples were collected for the retrieval and quantification of L3. Retrieval of L3 from feces and forage was negligible in winter due to the dry weather, although a few larvae were retrieved in the last larval collections. However, L3 retrieval from fecal samples was greater in spring, especially two weeks after feces were deposited on 30 cm high grasses. At this time, the L3 retrieval rate from the three forage grasses differed significantly (P <0.05), with Aruana grass showing the highest average L3 retrieval rate, followed by Coast-cross and Brachiaria. In conclusion, the winter drought proved very unfavorable for the presence of L3 in the environment, and the microclimate of Aruana pastureland was generally the most favorable for the retrieval of infective larvae.
authors.affiliation: Departamento de Zootecnia, Universidade de Ponta Grossa - UEPG, Ponta Grossa, PR, Brasil.
authors.forename: Raquel Abdallah da
authors.initials: RA
authors.lastname: Rocha
authors.affiliation: Departamento de Zootecnia e Desenvolvimento Rural, Centro de Ciências Agrárias, Universidade Federal Santa Catarina - UFSC, Florianópolis, SC, Brasil.
authors.forename: Patrizia Ana
authors.initials: PA
authors.lastname: Bricarello
authors.affiliation: Departamento de Produção Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista - UNESP, Botucatu, SP, Brasil.
authors.forename: Gilberto Pedroso da
authors.initials: GP
authors.lastname: Rocha
authors.affiliation: Departamento de Parasitologia, Instituto de Biociências, Universidade Estadual Paulista - UNESP, Botucatu, SP, Brasil.
authors.forename: Alessandro Francisco Talamini do
authors.initials: AF
authors.lastname: Amarante
mesh_terms: D000818:Animals; D001938:Brazil; D005243:Feces / Q000469:parasitology; D007814:Larva; D006109:Poaceae / Q000469:parasitology*; D012621:Seasons; D012756:Sheep; D014254:Trichostrongylus / Q000302:isolation & purification*