Reproductive consequences of infection with bovine viral diarrhea virus

Genetic typing of bovine viral diarrhoea virus in cattle on Irish farms

“…Alternatively a PI dam will always yield a PI calf (Bolin 2002 (Brownlie et al 1998). After day 125 of gestation a foetus typically has adequate immunocompetence to mount an effective immune response against BVDV infection and are born seropositive (Grooms 2004;Radostits and Littlejohns 1988).…”

“…Congenital defects are highly variable with central nervous system (CNS) defects most frequently observed (Grooms 2004). Congenital defects develop in the foetus typically when infected during the mid-gestation stage (Radostits and Littlejohns 1988).…”

“…If this population of females become infected with BVDV the outcome is dependent on the age and immunological maturity of the foetus at the time of infection (Altamiranda et al 2013). Numerous studies suggest varying timelines of gestation as to when immunotollerance is initiated, ranging from 18 to 125 days of gestation indicating that case to case variation exists (Bolin 2002;Grooms 2004;Lanyon et al 2004;Evermann and Ridpath 2002).…”

“…Reduced reproductive performance, including reduced conception rates and early embryonic death are likely to occur if infection occurs early in gestation. Transplacental BVDV infection of foetuses can result in congenital defects and immunotolerance to the virus, resulting in the birth of a PI calf (Grooms 2004;Lanyon et al 2004;Evermann and Ridpath 2002). Infection during late gestation, (>125 days), can result in weak or under developed calves or the foetus may mount an effective immune response and be normal at birth (Evermann and Ridpath 2002).…”

“…BVDV can induce a broad range of disease in cattle including; fever, diarrhoea, ill thrift, reduced milk yield, reduced reproductive performance, immunosuppression and, in a high proportion of cases, subclinical infection which often may go undetected (Peterson 2010;Paton et al 1989;Grooms 2004;Lanyon et al 2004;…”