Abstract: Embodiments of the present invention provide a pharmaceutical intervention in the neonatal pig that inhibits and delays development and activation of the HPG axis, growth of the boar testis and inhibits testicular production of testosterone and androstenone, which prevents the development of aggressive behavior in the maturing boars and the presence of boar taint in the meat. The invention comprises treatment with a combination of an androgen and an estrogen in the newborn male piglet using extended drug delivery methods, with a defined duration of no more than 12 weeks, for the purpose of inhibiting the production of testosterone and androstenone and the accumulation of the boar taint-inducing molecules androstenone and skatole in the fat.

Abstract: Methods, compositions and systems are presented to deliver estradiol benzoate to an animal so as to sterilize the animal. A physiologically acceptable oil or other carrier in a capsule is used to deliver the estradiol benzoate. The estradiol benzoate is delivered intraperitoneally, intramuscularly, or subcutaneously to a companion or livestock animal.