Effect of dietary crude protein content on skatole concentration in boar serum

Forty-eight Yorkshire × Chester White crossbred boars, 28 days of age, were assigned to one of four diets differing in crude protein content. Dietary crude protein content was 23% initially and then adjusted to 14, 17, 20 or 23% at 9 weeks of animal age, and 12, 15, 18 or 21% at 14 weeks of age, respectively. The skatole concentrations in serum of the boars was measured at 24, 32 and 40 weeks of age. Results showed that serum skatole concentrations declined (P < 0·05) with increasing age (0·034, 0·027 and 0·021 μg/ml at 24, 32 and 40 weeks, respectively) and also decreased (P < 0·059) with increasing dietary crude protein concentration (0·033, 0·026, 0·022 and 0·021 μg/ml at 12, 15, 18 and 21% in finishing diets, respectively).