Trials with the Haemonchus vaccine, Barbervax ® , in ewes and lambs in a tropical environment: Nutrient supplementation improves protection in periparturient ewes.

Autor: Bassetto CC; UNESP - Universidade Estadual Paulista, Departamento de Parasitologia, Instituto de Biociências, Botucatu, SP, CEP 18.618-689, Brazil. Electronic address: cesarbassetto@gmail.com., Almeida FA; UNESP - Universidade Estadual Paulista, Departamento de Parasitologia, Instituto de Biociências, Botucatu, SP, CEP 18.618-689, Brazil., Newlands GFJ; Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK., Smith WD; Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK., Castilhos AM; UNESP - Universidade Estadual Paulista, Departamento de Produção Animal, Faculdade de Medicina Veterinária e Zootecnia, Fazenda Experimental Lageado, Botucatu, SP, Brazil., Fernandes S; UNESP - Universidade Estadual Paulista, Departamento de Produção Animal, Faculdade de Medicina Veterinária e Zootecnia, Fazenda Experimental Lageado, Botucatu, SP, Brazil., Siqueira ER; UNESP - Universidade Estadual Paulista, Departamento de Produção Animal, Faculdade de Medicina Veterinária e Zootecnia, Fazenda Experimental Lageado, Botucatu, SP, Brazil., Amarante AFT; UNESP - Universidade Estadual Paulista, Departamento de Parasitologia, Instituto de Biociências, Botucatu, SP, CEP 18.618-689, Brazil.
Jazyk: angličtina
Zdroj: Veterinary parasitology [Vet Parasitol] 2018 Dec 15; Vol. 264, pp. 52-57. Date of Electronic Publication: 2018 Nov 08.
DOI: 10.1016/j.vetpar.2018.11.006
Abstrakt: 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.
(Copyright © 2018 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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