Avaliação da transmissão da imunidade passiva e efeitos fisiopatológicos frente a infecção experimental primária e desafio de cordeiros com Haemonchus placei e H. contortus

Detalhes bibliográficos
Ano de defesa: 2012
Autor(a) principal: Reiniger, Regina Celis Pereira
Orientador(a): Berne, Maria Elisabeth Aires
Banca de defesa: Não Informado pela instituição
Tipo de documento: Tese
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Pelotas
Programa de Pós-Graduação: Programa de Pós-Graduação em Veterinária
Departamento: Veterinária
País: BR
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: https://guaiaca.ufpel.edu.br/handle/123456789/2496
Resumo: The aim of this study was to evaluate the effect of the transfer of passive immunity and pathophysiological effects against experimental Haemonchus placei or H. contortus primary infection and challenge. The first experiment evaluated the transmission of passive immunity in parasite-free lambs. At 6-month old, lambs were divided in three groups: infected with H. contortus (Hc), with H. placei (Hp) and uninfected (C for control), and challenged at 9-month old when lambs were again divided in four groups: Hc-Hc, Hc-Hp, Hp-Hc and C-C. Serological analyses showed the transfer of anti-H. contortus IgG, but with a gradual decline over time in both females and lambs. During primary infection, faecal egg count (FEC) average was twice for the Hc group compared to Hp (p <0.0001). The Hc group presented the lowest packed cell volume compared to the other groups (p <0.0001). Primo-infected sheep with either H. placei or H. contortus did not develop resistance when challenged with same species- or across-species parasite. Single 5,000 L3 dose experimental infection was not sufficient to cause clinical signs, nor to rise and maintain anti-H. contortus IgG levels in the infected animals. There is passive transfer of anti-H. contortus IgG for lambs through the colostrum, however the IgG levels begin a gradual decrease from day 30 after birth.