Abstract:
Inhibin is a gonadal hormone that inhibits the release of follicle stimulating hormone (FSH) from the
anterior pituitary gland. The objective of this study was to determine whether active immunization of
male and female rats against inhibin rich, steroid-free bovine follicular fluid would increase inhibin antibody
titre, onset of female puberty, pregnancy rate, litter size, testis weights, testosterone concentration
and serum FSH. Immunization of rats with steroid free bovine follicular fluid stimulated production
of anti-inhibin antibodies that immunoneutralized endogenous inhibins and increased levels
of circulating FSH in immunized males. Inhibin immunoneutralization resulted in early vaginal opening
in immunized females compared with controls and pregnancy rates were increased when immunized
female rats were mated with immunized males. However, serum testosterone, testis weights
and potential litter size remained unchanged. We conclude that methods to immunoneutralize inhibin
may have merit as therapeutic procedures to enhance reproductive performance in domestic animals.
