It is mainly high levels of Androstenone and skatole in adipose tissue that is the reason behind boar-taint, which is an unpleasant odor and taste from the meat of adult male boars. The purpose of this literature study is to provide an overview of current knowledge about the physioloical functioning of Androstenone. There are several studies showing Androstenone´s function as a pheromone, and that it is an important part of communication and mating behavior between pigs. Androstenone is produced in the testes of the boar and transported via the bloodstream to the salivary glands where it is excreted with the saliva. Sows sense the pheromone, not via the vomeronasal organ as previously considered, but via the olfactory mucosa.

Hundreds of thousands of piglets are castrated without anesthesia in Sweden every year so that we may be guaranteed meat without boar odor. The smell appears while cooking meat of boar and is described as urine- and sweat-like. High levels of Androstenone and skatole are considered the main factors behind boar odor. Skatole is a metabolite of the amino acid tryptophan, which is formed in the colon of all pigs. Androstenone is a steroid hormone that is released from the Leydig cells in the testes of boars.

SAMMANFATTNING Sedan lång tid tillbaka har hangrisar kastrerats för att undvika ornelukt, en fekal-urinliknande doft som uppkommer i galtkött vid tillagning. Kastrationen är smärtsam och forskarna letar nu efter alternativ till det kirurgiska ingreppet. I denna litteraturstudie har jag valt att fokusera på hur man kan hindra produktion och upplagring av orneluktsämnena androstenon och skatol i subkutant fett genom att förändra grisarnas miljö. Stallhygienen har visat sig ha betydelse för ornelukt där smutsiga grisar har betydligt högre halter skatol i subkutant fett än rena grisar. Även ljus och temperatur har en inverkan på orneluktsämnena. Höga temperaturer och korta ljusperioder ger ökade halter av androstenon och skatol.

An overwhelming majority of all male piglets are castrated without anaesthesia when they are very young. In Sweden this means that approximately one and a half million piglets are castrated every year. The reason the piglets are castrated is the strong and unpleasant smell and taste, the ?boar taint? that the meat from intact boars sometimes exhibits. Boar taint is chiefly cause by Androstenone and skatole, two compounds that are mostly produced by sexually mature boars and are accumulated in the subcutaneous fat.