Comparative study of natural carob fibre and psyllium husk in rats. Influence on some aspects of nutritional utilisation and lipidaemia

The effects of the addition of 100 g kg−1 of psyllium husk (PSY), cellulose (CEL) or natural carob fibre (NCF) to a semi-synthetic diet on fat (FD) and nitrogen (NF) digestibility coefficients, metabolic nitrogen utilisation (MNU), net nitrogen utilisation (NNU) and total serum cholesterol and triglyceride levels, were studied in male ‘Wistar’ rats. No significant differences were observed between the three fibres with respect to the weight increase of the animals or MNU. Significant differences were recorded for the FD of the NCF group (0.91±0.01) compared to the CEL group (0.95±0.01), as well as on ND (0.88±0.00 NCF group, 0.88±0.00 PSY group and 0.95±0.00 CEL group) and NNU. None of these indexes showed differences between the groups PSY and NCF. For the serum cholesterol levels, there were no significant differences between the non-hypercholesterolaemic groups fed PSY, CEL or NCF; in those in which hypercholesterolaemia was induced (cholesterol and bile bovine 8.3 g kg−1), significantly lower values were found in the NCF group (166±17 mg dl−1 ) than in the PSY group (343±61 mg dl −1) and in the CEL group (386±48 mg dl−1).