Recent genetic advances on boar taint reduction as an alternative to castration: a review

Abstract

Boar taint is an unpleasant odor in male pig meat, mainly caused by androstenone, skatole, and indole, which are deposited in the fat tissue. Piglet castration is the most common practice to prevent boar taint. However, castration is likely to be banished in a few years due to animal welfare concerns. Alternatives to castration, such as genetic selection, have been assessed. Androstenone and skatole have moderate to high heritability, which makes it feasible to select against these compounds. This review presents the latest results obtained on genetic selection against boar taint, on correlation with other traits, on differences in breeds, and on candidate genes related to boar taint. QTLs for androstenone and skatole have been reported mainly on chromosomes 6, 7, and 14. These chromosomes were reported to contain genes responsible for synthesis and degradation of androstenone and skatole. A myriad of work has been done to find markers or genes that can be used to select animals with lower boar taint. The selection against boar taint could decrease performance of some reproduction traits. However, a favorable response on production traits has been observed by selecting against boar taint. Selection results have shown that it is possible to reduce boar taint in few generations. In addition, modifications in diet and environment conditions could be associated with genetic selection to reduce boar taint. Nevertheless, costs to measure and select against boar taint should be rewarded with incentives from the market; otherwise, it would be difficult to implement genetic selection.

Effect of SNPs in the Promoter Region on the Expression of Cytochrome P450 2E1 (CYP2E1) in Pig Liver

“…There are distinct breed differences in the amount of boar taint, with higher levels of skatole and androstenone and boar odor found in Large White boars compared to Pietran and higher levels of androstenone in Duroc compared to Landrace boars. Overall, higher levels of boar taint compounds are found in dam compared to sire lines (reviewed in [4]). It may be possible to decrease the occurrence of boar taint by manipulating factors that reduce the synthesis or increase the metabolism of androstenone or skatole.…”

Masking strategies to avoid the boar taint in meat products

“…Boar taint is an offensive smell found in male pork meat that is mostly brought on by androstenone, skatole, and indole accumulation in fat tissue (Duarte et al, 2021). Most experts agree that androstenone and skatole are the main chemicals to blame for swine taint (Meinert et al, 2017).…”

“…Starting with tryptophan, skatole and indole are created in the intestine and further are broken down in the liver. At sexual maturity, androstenone, skatole, and indole are accumulated in fat tissue (Duarte et al, 2021). The sensory perception thresholds for androstenone and skatole, chemicals that cause boar taint, are typically between 0.20 and 0.25 ppm and 0.5 to 1.0 ppm, respectively (Lundstrom et al, 2009).…”

“…The sensory perception thresholds for androstenone and skatole, chemicals that cause boar taint, are typically between 0.20 and 0.25 ppm and 0.5 to 1.0 ppm, respectively (Lundstrom et al, 2009). Boar taint is influenced by things like breed, which affects the genetics of the animals, age, nutrition, and rearing conditions upbringing (Duarte et al, 2021). Fig.…”

“…Boar taint compounds (Bilić-Šobot, 2016;Čandek-Potokar, 2017) Historically, surgical castration of male piglets has been used to prevent the appearance of boar taint. However, castration is likely to be forbidden in the coming years because of worries about animal welfare (Duarte et al, 2021). For moving away from surgical castration, there are primarily two methods.…”