Dietarily induced changes in liver composition and weight of fattening rabbits

Forty eight New Zealand × Californian rabbits were used to investigate the effects of diets with either a low (LDF) or high (HDF) inclusion of sugar beet pulp and wheat bran (feedstuffs rich in degradable fibre; DF) supplemented with or without soybean oil (20 g SO/kg) on liver weight and composition, according to a 2 × 2 factorial arrangement. At 77 days of age, the livers were excised, weighed, and analyzed for glycogen, cholesterol, and protein content and fatty acid (FA) composition. The HDF diets decreased liver relative weight (g/100 g body weight; P < 0.001), glycogen (P < 0.05) and cholesterol (P < 0.01) content, and monounsaturated FA (MUFA) (P < 0.05). SO addition also decreased liver weight (P < 0.001), glycogen (P < 0.05) content, saturated FA (SFA) (P < 0.01), and MUFA (P < 0.001). Principal component analysis (PCA) adequately described the relationships between the major FA of liver. Moreover it showed that 18:0 was not strictly of de novo origin, as were 14:0 and 16:0. Liver weight was positively correlated to glycogen and cholesterol content (P < 0.001), as well as to SFA (14:0 and 16:0; P < 0.01) and MUFA (P < 0.001) composition. In conclusion, liver weight of fattening rabbits can be affected by changes in cholesterol, glycogen content and FA composition induced by modified dietary DF and SO content.