Publicação: Trials with the Haemonchus vaccine, Barbervax®, in ewes and lambs in a tropical environment: Nutrient supplementation improves protection in periparturient ewes
Carregando...
Data
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Tipo
Artigo
Direito de acesso
Acesso aberto
Resumo
Haemonchus contortus is an economic problem in sheep farms worldwide, mainly in the tropics and subtropics. A vaccine against haemonchosis, called Barbervax®, was evaluated in ewes under two nutritional status, naturally infected with gastrointestinal nematodes. Ewes were divided into four groups: Supplemented Diet – Vaccine; Supplemented Diet – No vaccine; Basal Diet – Vaccine and Basal Diet – No vaccine. Their lambs were divided in Vaccinated and No vaccine. Ewes were immunised six times starting about 1 month of pregnancy with the first three doses at 3 week intervals and the last three shots at 4 week intervals. Supplemented ewes had higher body weight, body score and packed cell volume compared with those fed a basal diet. Both groups of vaccinated ewes showed a similar response in circulating anti-vaccine antibodies but the vaccine had no discernible effect on either body weight, body score and packed cell volume. There was a marked group difference in the number of ewes that received precautionary treatments with anthelmintic. All 14 Basal Diet – No vaccine ewes required treatment. In contrast only 7 ewes, in the Supplemented Diet – Vaccine group required anthelmintic treatment. In the Basal Diet – Vaccine and in the Supplemented Diet – No Vaccine groups, 12 and 13 ewes needed anthelmintic treatment, respectively. Vaccinated lambs showed much higher antibody titres resulting in 80% less Haemonchus spp. egg counts comparing with no vaccine lambs. Taken together these results clearly suggest that in pregnant and lactating ewes a combined protective effect between vaccination and improved nutrition resulted in fewer precautionary anthelmintic treatments. Thus, it was possible to achieve a more sustainable level of control of the haemonchosis, less dependent on anthelmintic drugs.
Descrição
Palavras-chave
Haemonchosis, Improved nutrition, Parasitic gastroenteritis, Prophylaxis, Sheep
Idioma
Inglês
Como citar
Veterinary Parasitology, v. 264, p. 52-57.
