Parasitism by Oestrus ovis: Influence of sheep breed and nematode infections

Autor(es)

Silva, B. F. ^[1] ; Bassetto, C. C. ^[1] ; Shaw, R. J. ^[2] ; Canavessi, A. M. O. ^[3] ; Amarante, A. F. T. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista UNESP, Dept Parasitol, Inst Biociencias, BR-18618000 Botucatu, SP - Brazil

^[2] AgResearch, Hopkirk Res Inst, Palmerston North 4442 - New Zealand

^[3] Univ Sao Paulo, Dept Zootecnia, ESALQ, BR-13418900 Piracicaba - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Veterinary Parasitology; v. 186, n. 3-4, p. 437-444, MAY 25 2012.
• Citações Web of Science: 6

Resumo

Previous studies showed that Santa Ines (SI) hair sheep were more resistant to gastrointestinal nematode infections (GIN) than Ile de France (IF) sheep. The present experiment aimed to evaluate if that reported resistance difference against GIN also occurred against Oestrus ovis infestation and also to evaluate the influence of O. ovis infestation on the gastrointestinal nematodes (GIN) infections. SI (n = 12) and IF (n = 12) young male lambs were weaned at 2 months of age and moved to a paddock (0.3 ha) with Brachiaria decumbens grass, where they also received concentrate ration. The animals were kept together during the experimental period (September to early December 2009). Fecal and blood samples were taken from all animals every 2 weeks and body weight and nasal discharge score (oestrosis clinic signs) were recorded on the same occasion. In early December 2009, all lambs were sacrificed and O. ovis larvae and GIN were recovered, counted and identified according to the larval stage. All animals were infested by different larval instars of O. ovis without any statistical difference between breeds (P > 0.05). The SI lambs had an average of 24.8 larvae, and the intensity of infection ranged between 14 and 39 larvae, while the IF lambs showed an average of 23.5 larvae with the minimum and maximum from 11 to 36 larvae, respectively. SI lambs presented the lowest nematode fecal egg counts (FECs) and the lowest mean numbers of Haemonchus contort us, Trichostrongylus colubriformis and Strongyloides papillosus, however, there was no significant differences between group means (P > 0.05). Inverse relationship between numbers of O. ovis larvae and gastrointestinal nematodes was observed in both breeds. SI sheep showed a significant increase in blood eosinophils and total IgE serum levels and these variables were negatively correlated with nematode FEC. A negative correlation was observed between total IgE serum level and H. contortus burden in both breeds. In conclusion, there was no breed difference regarding O. ovis infestation and in each breed, animals with more nasal bot fly larvae tended to display smaller worm burden. (C) 2011 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 08/53494-2 - Epidemiologia das infestacoes por oestrus ovis em ovinos criados em botucatu e influencia da raca ovina no parasitismo
• Beneficiário: Alessandro Francisco Talamini Do Amarante
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/58244-1 - Epidemiologia das infestações por Oestrus ovis em ovinos criados em Botucatu e influência da raça ovina no parasitismo
• Beneficiário: Bruna Fernanda da Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 09/03504-4 - Proteção de bovinos contra Haemonchus placei e Haemonchus contortus após imunização com antígenos oriundos da membrana intestinal de H. contortus.
• Beneficiário: César Cristiano Bassetto
• Modalidade de apoio: Bolsas no Brasil - Mestrado