Relationships between skatole and androstenone accumulation, and cytochrome P4502E1 expression in Meishan × Large White pigs

The effects of age, castration and diet on accumulation of skatole and androstenone in the backfat of 50% Meishan male pigs, was studied in relation to boar taint. Skatole and androstenone deposition in backfat of entire males was increased with age (114, 144 and 174 days). Castration significantly decreased skatole and androstenone levels in all age groups. The level of cytochrome P4502E1, the initial enzyme involved in hepatic skatole metabolism, was increased by castration at all ages. These results suggest that the decrease in androstenone levels following castration affects the regulation of cytochrome P4502E1 expression, and as a consequence, results in a decrease in skatole levels. The use of sugar beet feed in the diet decreased the level of skatole and increased that of cytochrome P4502E1 expression, but did not affect androstenone levels. It is suggested that skatole accumulation is reduced both by castration and by diet via induction of cytochrome P4502E1. However, the mechanism of induction of cytochrome P4502E1 by diet is different from that involved in its induction by castration.