effect of dietary supplementation with rapeseed and fish oil mixture ...

9 th World Rabbit Congress – June 10-13, 2008 – Verona – ItalyTable 3: Level of fatty acids (% total acids), total cholesterol (mg/100 g) and TBA (mg/kg) in themuscle tissue of hind legItem Group - I Group - II Group – III seC8:0 0.03 0.01 0.02 0.02C10:0 0.53A 0.10B 0.14B 0.18C12:0 0.34 0.10 0.14 0.10C14:0 2.41a 2.51a 3.28b 0.16C16:0 21.8a 17.6ab 19.9b 1.17C16:1 3.25 3.27 4.22 0.45C18:0 5.45 4.44 4.48 0.19C18:1 21.8A 17.1B 17.9B 0.61C18:2n-6 38.5 38.7 35.1 1.41C18:3n-3 2.12A 5.47B 3.95B 0.93C20:0 0.09A 0.06B 0.05B 0.01CLAc9t11 0.05 0.06 0.06 0.01CLAt10c12 0.01A 0.09B 0.08B 0.01CLAc9c11 0.01 0.01 0.01 0.01CLAt9t11 0.51A 1.29B 1.32B 0.12C20:4n-6 1.77A 0.95B 0.88B 0.12C22:1 0.03 0.02 0.06 0.04C20:5n-3(EPA) 0.13A 1.52B 1.70B 0.01C22:6n-3(DHA) 0.93A 6.32B 6,38B 0.17SFA 30.7a 24.9b 28.0b 1.48PUFA 44.2A 54.6B 49.7B 1.90PUFAn-6 40.4 39.8 36,1 1.38PUFAn-3 3.20A 13.3B 12.0B 0.91PUFA/SFA 1.44A 2.20B 1.78A 0.18PUFAn-6/n-3 13.4A 3.01B 3.05B 1.12Cholesterol 66.3a 60.5 57.5b 3.61Vitamin E 1.81A 2.19A 3,56B 0.47TBA-RS14 0.34A 0.33A 0.17B 0.25TBA-RS90 0.51A 0.52A 0.20B 0.14a,b: means with different letters differ significantly at P≤0.05, A,B: at P≤0.01The addition of vitamin E to the diet at a rate of 100 mg/kg had a beneficial effect on reducing thesusceptibility of muscle lipids to oxidation processes during the frozen storage of meat. Similarfindings were reported by Connor (2000) and Ramirez et al. (2005), who showed a positive effect ofadding fat to rabbit diets on the level of desirable fatty acids and on reducing cholesterol in rabbitmeat.Cooking was applied as the meat preparation method for sensory analysis of the musculus longissimusdorsi (Table 4). This resulted from the fact that the analysis should give special attention to the aromaof the samples. This heat treatment method is the most effective in eliciting the intensity and typicalaroma of rabbit meat, and is not objected to by panelists on the grounds of the samples beingundercooked. No statistical differences were found between the groups in the overall sensory quality,which shows that the addition of rapeseed and fish oils had no negative effect on the sensory traits ofmeat.Table 4: Sensory traits of meat (mean scores)Trait Group I Group II Group III seAroma intensity 4.8 4.8 4.8 0.01Aroma quality 4.2 4.0 4.0 0.05Tenderness 4.4 4.8 4.8 0.22Juiciness 4.4 4.6 4.6 0.07Taste intensity 4.0 4.0 4.0 0.01Taste quality 4.6 4.6 4.6 0.01Overall sensory quality 4.40 4.45 4.46 0.06CONCLUSIONSIn summary, the addition of rapeseed oil (2%) and fish oil (1%) to rabbit diets had a favourable effecton the composition of the meat lipid fraction. There was a decrease in the total level of saturated fatty1374