Immunisation of male pigs with Improvac induces an immune response against endogenous gonadotrophin releasing factor (GnRF), a factor that controls testicular function via the gonadotrophic hormones LH and FSH. The active ingredient in this immunological is a synthetically produced analogue of GnRF, which is conjugated with an immunogenic carrier protein. The conjugate is adjuvanted to increase the level and duration of effect.
The effects of immunisation derive from the reduction in testicular function resulting from reduced GnRF activity. This leads to reduced production and concentration of testosterone and other testicular steroids, including androstenone, one of the main substances responsible for boar taint.
A reduction of typical male behaviour such as mounting and aggressiveness when mixed with non-penmates can be expected after the second vaccination.
Boars given an initial dose of Improvac are immunologically primed but retain their full testicular function until they receive the second dose, which induces a strong immune response to GnRF and causes temporary immunological suppression of testicular function. This directly controls the production of androstenone and, by removing the inhibitory effect of testicular steroids on hepatic metabolism, indirectly reduces levels of skatole.
This effect is apparent within one week of treatment but it may take up to 3 weeks for any existing concentrations of boar taint compounds to be reduced to insignificant levels.
Immunisation of female pigs with Improvac induces an immune response against endogenous gonadotrophin releasing factor (GnRF), a factor that controls ovarian function via the gonadotropic hormones, LH and FSH. The active ingredient in this immunological is a synthetically produced analogue of GnRF, which is conjugated with an immunogenic carrier protein. The conjugate is adjuvanted to increase the level and duration of effect.
The effects of immunisation derive from the reduction in ovarian function resulting from reduced GnRF activity. This leads to reduced production and concentration of oestradiol and progesterone. Prevention of typical female behaviour (standing oestrus) and prevention of potential pregnancy can be expected from 1 to 2 weeks post second vaccination; prevention of pregnancy is particularly relevant in situations where fattening entire males and females are commingled.
Disposal
Any unused veterinary medicinal product or waste materials derived from such veterinary medicinal products should be disposed of in accordance with local requirements.