Título:	Seasonal prevalence of gastrointestinal nematodes of beef cattle grazed on irrigated pastures in the lower Sacramento Valley of California.
Autoria:	CHARLES, T. P. BAKER, N. F.
Afiliação:	TEREZINHA PADILHA CHARLES, CPATSA.
Ano de publicação:	1988
Referência:	American Journal of Veterinary Research, v. 49, n. 4, p. 566-571, 1988.
Conteúdo:	Two worm-free calves were allowed to graze on irrigated pasture with a naturally infected herd for each of 34 one-month periods from November 1979 to August 1982. After each grazing period, the calves were transferred to a cement-floored pen for 3 weeks and then were euthanatized and necropsied. Ostertagia ostertagi and Cooperia oncophora were the most prevalent species of nematodes recovered. Adults and larvae of Ostertagia spp and Cooperia spp were most numerous in winter and spring and least numerous during summer. The proportions of Ostertagia spp that were inhibited as fourth-stage larvae increased in late fall, peaked from March through April, and then decreased to low values during summer. The maximal inhibition in 1980, 1981, and 1982 was 72, 65, and 62%, respectively. The number of larval Cooperia spp was highest in winter months and, except for one grazing period when 55% of the Cooperia spp were larvae, the total numbers represented less than 15% of the nematode population during all grazing periods. Other nematodes encountered were Trichostrongylus axei, Haemonchus spp, O lyrata, and O occidentalis in the abomasum; C surnabata, C punctata, Nematodirus helvetianus, T colubriformis, and Bunostomum phlebotomum in the small intestine; and Oesophagostomum venulosum and Trichuris ovis in the large intestine
Thesagro:	Bovino
NAL Thesaurus:	California animal pathology beef cattle
Palavras-chave:	Patologia animal Nematoide gastrointestinal Pastagem irrigada Vale do Sacramento Nematode Irrigated pasture Sacramento Valley
Tipo do material:	Artigo de periódico
Acesso:	openAccess
Aparece nas coleções:	Artigo em periódico indexado (CPATSA)