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

Author(s)

Bassetto, C. C. ^[1] ; Almeida, F. A. ^[1] ; Newlands, G. F. J. ^[2] ; Smith, W. D. ^[2] ; Castilhos, A. M. ^[3] ; Fernandes, S. ^[3] ; Siqueira, E. R. ^[3] ; Amarante, A. F. T. ^[1]

Affiliation

^[1] Univ Estadual Paulista, UNESP, Dept Parasitol, Inst Biociencias, Dist Rubiao Jr S-N, BR-18618689 Botucatu, SP - Brazil

^[2] Moredun Res Inst, Pentlands Sci Pk, Edinburgh, Midlothian - Scotland

^[3] Univ Estadual Paulista, UNESP, Dept Prod Anim, Fac Med Vet & Zootecnia, Fazenda Expt Lageado, Botucatu, SP - Brazil

• Document type: Journal article
• Source: Veterinary Parasitology; v. 264, p. 52-57, DEC 15 2018.
• Web of Science Citations: 3

Abstract

Haemonchus contortus is an economic problem in sheep farms worldwide, mainly in the tropics and subtropics. A vaccine against haemonchosis, called Barbervax (R), 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. (AU)

• FAPESP's process: 15/00221-2 - Vaccination of sheep against Haemonchus contortus
• Grantee: César Cristiano Bassetto
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/25718-7 - Prophylaxis of sheep worms using integrated crop-livestock system (ICL)
• Grantee: Fabiana Alves de Almeida
• Support Opportunities: Scholarships in Brazil - Post-Doctoral