In vivo and in vitro studies on the effect of gentamicin sulfate on the efficacy of the turkey herpesvirus vaccine.

Abstract

In vitro studies indicate that the titer of the cell-free or cell-associated turkey herpevirus (HVT) vaccine was not appreciably reduced when incubated with .1, .2, or .3 mg of gentamicin sulfate for up to 2 hr. However, the titer of both the cell-free and cell-associated HVT vaccines was reduced when incubated with .4 mg of gentamicin sulfate for 2 hr. However, in vivo studies show that the incidence of Marek's disease (MD) in chickens which were vaccinated with the cell-free or cell-associated HVT vaccine which had been incubated with ,1, .2, .3, or .4 mg of gentamicin sulfate up to 2 hr was not increased when compared to chickens receiving only the HVT vaccine. The results of other laboratory studies also show that there was no increase in the incidence of MD when comparing chickens which received either 1360 or 6360 PFU of cell-free HVT vaccine or 1250 or 5690 PFU of cell-associated HVT vaccine to those vaccinated with the same doses of cell-free or cell-associated HVT vaccine containing .2 mg of gentamicin sulfate.