The integrated metabolism of boar taint - towards developing effective strategies to reduce taint.

点击翻译按钮获取中文摘要

Boar taint is an off-odour or off-flavour in heated pork products from entire male pigs (boars). It is caused by the accumulation of high levels of 16-androstene steroids (androstenone), which are produced in the testis, and skatole and other indoles, which are produced from tryptophan by the gut microflora. Male pigs are normally castrated to prevent boar taint, but animal welfare concerns against castration have led several EU countries to ban surgical castration (www.boars2018.com) and it is only a matter of time before this becomes an important issue in North America. Controlling boar taint without castration would also improve growth, increase lean yield, improve feed utilization and decrease feed consumption, which will improve profitability and reduce the environmental impact of pork production from reduced energy costs and less manure per unit of pork produced. A number of dietary additives and management practices have been described to decrease boar taint without castration, but the response to these treatments varies among individual pigs. ***Our lab has made significant contributions to the understanding of the integrated metabolism of boar taint compounds, with the overall goal of designing effective treatment methods to control boar taint. We have not yet investigated the causes for the variations in boar taint among individual pigs. Moreover, some aspects of the metabolism of boar taint compounds have not yet been fully explored. This includes the metabolism of 16-androstene steroids in the testis and liver, the transport of 16-androstene steroids in plasma and their uptake by adipocytes. The relationship between the gut microbiome and the physiology of the individual pig on the production and absorption of skatole from the gut and metabolism by the liver is also not fully understood. A more complete understanding of these processes may provide further opportunities to develop methods to reduce boar taint.***We have identified a number of Single Nucleotide Polymorphisms (SNPs) in genes involved in boar taint metabolism with the goal of developing genetic tools and selection protocols to reduce boar taint. We now plan to determine how the mutations affect the expression of these genes and the activity of the gene products, so we can understand how they can alter the amount of boar taint. We can also use this genotype information to develop effective treatment protocols to reduce boar taint in individual animals based on their genotypes.***Our objectives are: 1. To complete work on the characterization of aspects of boar taint metabolism, 2. To integrate metabolic, physiological and genomic information to define the processes that lead to individual differences in boar taint and 3. To use this information to develop novel and effective methods to decrease boar taint without castration.**