Feeding with chicory roots reduces the amount of odorous compounds in colon and rectal contents of pigs

Abstract

Sixteen pigs (eight entire males and eight females) were given individually two diets, control and control added 25% chopped chicory roots for 2 months before slaughter. Samples were taken from the contents in colon and rectum and subjected to GC-MS analysis for amount of odour impact compounds. The compounds 2-pentanone, ethylbutyrate, propylpropionate, butyric acid, ethyl-2-methylbutyrate, p-cresol, indole and skatole showed a significant difference between the two treatments. The esters, which have relatively pleasant, often fruity odours, increased in the chicory treatment, whereas the malodorous compounds, p-cresol, indole and skatole decreased in the chicory treatment. The measured amounts of compounds were corrected for their odour thresholds as different compounds can have widely different odour thresholds. Principal components analysis was then used to analyse the raw and corrected data results. p-Cresol was the most malodorous compound and together with skatole and indole count as the most malodorous compounds in the colon and rectum cotents. However, butyric acid also had some minor influence. Feeding chicory roots decreased significantly the concentrations of these malodorous compounds, especially if the lowest odour threshold values are used as correction factors.

Feeding Jerusalem artichoke reduced skatole level and changed intestinal microbiota in the gut of entire male pigs

“…Our results showed that increasing levels of Jerusalem artichoke in the diet resulted in a dose-dependent decrease in skatole levels in the hindgut and a corresponding trend for skatole in adipose tissue. In agreement with the present experiment, several studies with pigs reported reduced skatole levels in intestinal content, plasma or adipose tissue when fermentable carbohydrates were fed (Knarreborg et al, 2002;Jensen and Hansen, 2006;Øverland et al, 2011). Hansen et al (2006) added crude and dried chicory and chicory-inulin in diets for pigs (25% of total energy intake) during different periods before slaughter, ranging from 1 to 9 weeks.…”

“…Skatole production in the hindgut of pigs can be affected by the diet. Earlier studies report that feeding pigs diets supplemented with carbohydrates not enzymatically hydrolysed in the small intestine, but fermented in the hindgut, can reduce skatole levels in the hindgut (Jensen et al, 1995a;Jensen and Hansen, 2006;Øverland et al, 2011) and the accumulation in adipose tissue (Zamaratskaia et al, 2004a;Hansen et al, 2006;Pauly et al, 2008).…”

Effect of feeding fermentable fibre-rich feedstuffs on meat quality with emphasis on chemical and sensory boar taint in entire male and female pigs

“…Blue lupines have a high content of soluble none starch polysaccharides (NSP) and oligosaccharides (Fernadez & Batterham, 1995), which can be used as energy source for the microbes in the large intestine. Inclusion of fermentable carbohydrates in the diet results in a change from protein to carbohydrate fermentation and through that a decreased production of off-odour compounds such as skatole and p-cresol (Jensen & Hansen, 2006;Rideout, Fan, Cant, Wagner-Riddle, & Stonehouse, 2004) and a shift from ammonia (N) excretion to microbial protein in faeces (Canh, Verstegen, Aarnink, & Schrama, 1997;Nahm, 2003).…”

“…The ''boar" taint in the female pigs is therefore only present as a result of skatole and indole production in the GI tract. Chicory and lupine were assumed to mainly affect the skatole aspect due to their effect on the skatole production across the digestive tract since diets with high content of fermentable carbohydrates have been shown to reduce the production of skatole and p-cresol (Jensen & Hansen, 2006). Thus, the feeding treatments were not expected to affect the level of sensory androstenone.…”

Quantitative determination of the boar taint compounds androstenone, skatole, indole, 3α-androstenol and 3β-androstenol in wild boars (Sus scrofa) reveals extremely low levels of the tryptophan-related degradation products

“…Moreover, several studies revealed that the feeding of easy fermentable carbohydrates such as raw potato starch or chicory inulin leads to significant decreased SK concentrations in back fat of domestic pigs (Chen et al, 2007;Hansen et al, 2008;Kjos, Øverland, Fauske, & Sørum, 2010). Microbes in the intestine change from protein to carbohydrate fermentation, when adequate amounts of carbohydrates are available (Hansen et al, 2008;Jensen & Hansen, 2007;O'Connell, Callan, & O'Doherty, 2006). As a consequence, less tryptophan is produced from protein degradation, resulting in a lower SK formation.…”