INFLUENCE OF STOCKING RATE AND FECES DEPOSITION IN THE PEN AT DIFFERENT TEMPERATURES ON SKATOLE CONCENTRATION (BOAR TAINT) IN SUBCUTANEOUS FAT

The aim of this work was to investigate the effect of stocking rate (0.6 m2 per pig or greater-than-or-equal-to 1.2 m2 per pig) and faeces plus urine deposition on skatole concentration (boar taint) in subcutaneous fat. The study utilized pens with concrete flooring and different environmental temperatures. The experimental material consisted of 144 crossbred male and female pigs in each of two experiments. One experiment was carried out in the summer (temperature greater-than-or-equal-to 22-degrees-C) and one in the winter (temperature approx. 17-degrees-C in the pig house). In both experiments, stocking rate and faeces deposition were kept constant up to first delivery to the abattoir. Then stocking rate and faeces deposition were changed to the opposite treatment a week before the last three of the four deliveries to the abattoir. The experiment confirmed the hypothesis that the pigs which lay in their faeces plus urine in pens with the high stocking rate for at least a week had a higher skatole level in subcutaneous fat than pigs kept clean in pens with the low stocking rate. It was feasible within a week before slaughter to increase or lower the skatole level by changing the treatment of the pigs. Male and female pigs showed similar differences. Air temperature (season) had a significant influence on skatole level. The level was significantly higher in subcutaneous fat at high temperatures in the summer experiment compared to the winter experiment despite the fact that the pigs with high stocking rate in the winter experiment were as heavily fouled with faeces and urine as those in the summer experiment. Skatole concentrations in faeces of individual pigs were not influenced by different temperatures or treatments, and there was no significant correlation between the skatole level in faeces and in subcutaneous fat. High skatole levels in subcutaneous fat seemed to have a genetic component. It is hypothesized that skatole from faeces plus urine (excreta) especially at temperatures of 30-degrees-C or more may pass through the skin of the pig and/or that skatole in a gaseous form may be absorbed through the lungs.