Dynamics of bovine herpesvirus type 1 infection in Estonian dairy herds with and without a control programme

Abstract

Bovine herpesvirus type 1 (BHV-1) is an important bovine pathogen, exacerbating poor health and the productivity of cattle. The aims of this study were to detect the efficacy of vaccination programmes in lowering the seroprevalence of BHV-1 gE within the dairy herd and to follow the dynamics of the infection in non-vaccinated herds with uninfected heifers. A two-year longitudinal study was carried out on seven herds that were vaccinated, and in five herds with uninfected heifers without applying a control programme. After the start of the vaccination programme, calves born remained free from the virus. However, in one herd, 7 per cent (95 per cent CI 2 to 18) of these animals showed antibodies to BHV-1 two years after the first vaccination. A decline in BHV-1 antibody prevalence was found in vaccinating herds. Among the five herds not under the control programme, one experienced active virus spread, although one herd experienced self-clearance of the virus. In the herds with high BHV-1 prevalence, vaccinating all cattle from three months of age twice a year with a commercial inactivated marker vaccine efficiently protected offspring from becoming infected, and lowered the prevalence of BHV-1 within the herd. A small proportion of herds may experience self-clearance of the virus.

Associations between exposure to bovine herpesvirus 1 (BoHV-1) and milk production, reproductive performance, and mortality in Irish dairy herds

“…As well as an overall herd analysis, investigations of Pp and Mp cows were completed to reflect the usual age profile of BoHV-1 in herds, a higher proportion of older animals within herds being seropositive (Jacevičius et al, 2010;Raaperi et al, 2012b). This was a useful exercise because it highlighted the fact the Pp cows would not appear to be affected by BoHV-1 to the same degree as Mp cows.…”

Prevalence of bovine herpes virus type 1 in small herds of young beef cattle in south-eastern Poland – a preliminary study

“…In Estonia, 22% of dairy herds are positive, and this percentage depends on herd size. There is also no systematic control programme in either dairy or beef cattle, except for bulls used for semen collection for artificial insemination (11,12,14).…”

Effect of vaccination against bovine herpesvirus 1 with inactivated gE-negative marker vaccines on the health of dairy cattle herds

“…Rispoval IBR Marker inactivatum (Pfizer Animal Health) (V+ I, II, III, IV, V and VII) and/or Bovilis IBR marker inac. (Intervet International) (V+ V and VI) were used (Raaperi et al, 2012a). Herds started with the vaccination between April 2007 and November 2008.…”

“…Continuous vaccination with live or inactivated gE-negative vaccines is reducing the circulation of the virus within a herd (Bosch et al, 1998;Mars et al, 2001;Vilmos et al, 2007;Jacevičius et al, 2008;Ampe et al, 2012;Raaperi et al, 2012a). By limiting the risk of having new BHV-1 gE-positive animals within the herd and by the gradual culling of field virus-infected animals, the herd may achieve IBR-free status (Makoschey and Bielsa, 2007).…”