The antioxidant effectiveness of liquorice (Glycyrrhiza glabra L.) extract administered as dietary supplementation and/or as a burger additive in rabbit meat.

The present research studied the effect of liquorice extract (in feed and/or directly in burgers) on the shelf-life of rabbit meat. Before weaning, 28 individually caged rabbit does with their litters were divided in two dietary groups: Control, receiving a commercial diet, and Liquorice, receiving the Control diet supplemented with 6 g liquorice extract/kg (L). At 12 weeks of age, 15 fattened rabbits/treatment (one rabbit/cage) were slaughtered and their hindlegs dissected. Hindleg meat was trimmed, individually minced and divided into two parts: one of them was mixed with 0.25% (w/w) L. Storage time significantly reduced the amount of polyunsaturated fatty acids in the burger, to a different magnitude depending on the unsaturation level, experimental group and storage time. The α-tocopherol content showed higher levels during storage in the burgers from the Liquorice group. Also TBARs values showed a significant positive effect of dietary liquorice and a progressive increase at days 3 and 6 of storage.

The effects of dietary quercetin supplementation and sex on the fatty acid profile of rabbit meat, dissectible fat and caecotrophes.

This study examined the effects of dietary quercetin on the fatty acid (FA) profile of rabbit caecotrophes, dissectible fat, Longissimus thoracis et lumborum (LTL) muscle and hindleg (HL) meat. Sixteen male and sixteen female New Zealand White rabbits were fed a control or quercetin-supplemented (2 g quercetin dihydrate/kg feed) diet from 5 to 12 weeks old, then slaughtered. Caecotrophes were collected from the gut, and the dissectible fat, LTL and deboned HL were sampled. Lipids in the samples were transmethylated, then identified and quantified using GC-FID. Quercetin-supplementation increased C18:0 in the fat, and C20:4n-6 in the LTL - suggesting an interaction with endogenous lipid metabolism - but had no effect on the HL and caecotrophes. Sex affected the caecotrophe FAs, but had little effect on the meat's nutritional value. The FA profiles of the LTL and HL differed, but both aligned to nutritional recommendations. The caecotrophe FA profile was indicative of microbial biohydrogenation, but this had minimal effect on the carcass FA.

Supplementing growing rabbit diets with chestnut hydrolyzable tannins: Effect on meat quality and oxidative status, nutrient digestibilities, and content of tannin metabolites.

The study investigated the effect of dietary inclusion of chestnut hydrolyzable tannin (CHT) in growing rabbit diets on nutrients digestibility, quality and oxidative status of meat, and content of tannin metabolites. At weaning, rabbits were assigned to 5 dietary groups (n = 72 rabbits/diet): control medication-free (Co), control with coccidiostat (Cc), and T200, T400 and T600 (diets supplemented with 200, 400 and 600 g/100 kg CHT extract). Sixteen carcasses/treatment were considered and hindleg meat and Longissimus thoracis et lumborum (LTL) muscle were used for analyses. L*a*b* color values, water holding capacity, Warner Bratzler shear force, haem iron content, oxidative status and nutritional quality were unaffected by dietary treatments. Saturated fatty acids (SFA) and monounsaturated FA (MUFA) in LTL meat were higher in T600 than Cc rabbits (P < .05), even though no differences were found for SFA and MUFA digestibility. Contrarily, polyunsaturated FA digestibility was lower in T400 and T600 than Co rabbits. No tannin metabolites traces were found in rabbit meat. Results of the present study showed that feeding CHT did not improve rabbit meat quality.

Effect of diet and packaging system on the oxidative status and polyunsaturated fatty acid content of rabbit meat during retail display.

The aim of this study was to evaluate the combined effect of two dietary lipid sources (sunflower vs. linseed oil) and three packaging methods (PVC film - BAG vs. modified atmosphere CO2 20% + 80% O2 - MAP vs. and vacuum - VAC) on the oxidative status and polyunsaturated fatty acid content of rabbit loins (Longissimus thoracis et lumborum muscle), at days 1, 4 and 10 of simulated retail display. The diet, storage time and packaging method affected the oxidative status of rabbit meat under retail display. As expected, storage time, independently on the other factors, significantly reduced the antioxidant content of loin meat. Accordingly, TBARs values significantly increased during storage, as well as the dietary supplementation of linseed. The fatty acid profile of the fresh loin closely respected that of the diets. At day 10, oxidative status and fatty acid profile of MAP samples could be yet considered optimal.

Dietary Spirulina (Arthrospira platensis) and Thyme (Thymus vulgaris) supplementation to growing rabbits: effects on raw and cooked meat quality, nutrient true retention and oxidative stability.

The study evaluated the effect of Spirulina and Thyme dietary supplementation on rabbit meat quality, nutrient true retention and protection against oxidative stress. Rabbits in the control group (C-C) received a non-supplemented pellet throughout the experiment (5-11weeks of age). In the other groups, the pellet contained 5% Spirulina (S), 3% Thyme (T), or both (ST) for either the entire (groups S-S, T-T, ST-ST) or only the final part of the growing period (8-11weeks: groups C-S, C-T, C-ST). Spirulina supplementation increased the γ-linolenic acid content of rabbit meat, whereas Thyme improved the oxidative stability of raw and freeze-dried meat.