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Abstract: In this experiment the effect of digestible energy (DE) restriction on carcass traits and meat quality of rabbits selected divergently for body fat content was studied. Using a 2×3 factorial arrangement, Pannon White rabbits selected for high (HFAT) or low (LFAT) total body fat content were fed isocaloric diets between 4 and 12 weeks of age. Energy restriction was achieved by reducing the daily feed intake by 10% (M) and 20% (L) compared to the ad libitum fed group (H). Proportional to the reduction of feed intake the nutrient density of diets M and L was increased. Thus, the DE intake was reduced while the nutrient intake remained stable among the 3 dietary groups. Effect of genetic group on carcass traits and on meat quality parameters was less marked than DE restriction. Selection for high body fat content improved the dressing out percentage (58.3 and 57.3% in HFAT and LFAT respectively; P <0.01), and reduced the percentage of the full gastrointestinal tract to slaughter weight (13.7 and 14.3% in HFAT and LFAT respectively; P <0.05). Reduction of DE intake decreased the body weight and the weight of the chilled and reference carcass (P <0.001), while it had no effect on dressing out percentage. In group H the percentage of fore part to reference carcass was higher (29.7 vs 29.0%; P <0.01) while that of the hind part was lower than in group L (37.0 vs 38.2%; P <0.001). The Longissimus lumborum meat from HFAT rabbits exhibited a lower content of moisture (76.1 and 76.5% in HFAT and LFAT respectively; P <0.01) as well as lower L⁎ (53.5 and 54.4 in HFAT and LFAT respectively; P <0.05) and b⁎ (0.42 and 0.81 in HFAT and LFAT respectively; P <0.05) colour values. When compared with ad libitum fed rabbits, those restricted at 20% (L) exhibited a higher content of moisture (76.9 vs 75.8%; P <0.01), as well as higher pHu (5.87 vs 5.73; P <0.01) associated with lower cooking loss (17.8 vs 19.1%; P <0.05). L rabbits also produced lower values of redness (a⁎, 2.21 vs 3.35; P <0.01) and yellowness (b⁎, 0.23 vs 0.91; P <0.01). No effect of the divergent selection for body fat content on the total lipid percentage and on most of the fatty acids in the meat of the hind leg was found. DE restriction resulted in lower SFA (L: 32.1 vs H: 35.8%; P <0.01) and MUFA (L: 21.0 vs H: 28.6; P <0.01) but higher PUFA contents (L: 45.5 vs H: 34.9%; P <0.01) in the hind leg meat. [Copyright &y& Elsevier]

Abstract: This 2×2×2 factorial experiment was conducted to study the effects of housing system (pair caged – cage – : 2 rabbits/0.122 m2 vs open top pen housed – pen – : 13 rabbits/0.86 m2; same stocking density), floor type (wire mesh vs plastic net), and environmental enrichment (with vs without gnawing stick) on the meat quality of Pannon White growing rabbits (n =64). The housing system significantly influenced slaughter weight (2590 vs 2531 g in cage or pen, respectively; P <0.01), reference carcass (RC) weight (1266 vs 1234 g; in cage or pen, respectively; P <0.05), and the hind leg meat to bone ratio (6.11 vs 5.62 in cage or pen, respectively, P <0.001). The animals reared in pens showed paler meat with lower pHu than that of those reared paired in cages. Hind leg meat dry matter and protein content were also influenced by the housing system (26.3 vs 25.9%, 21.9 vs 21.6%; in cage or pen, respectively; P <0.05). Pen housed rabbits had significantly heavier femur and tibia bone weight and higher fracture toughness than pair caged rabbits. Floor type affected the fore part/RC weight ratio (29.2 vs 29.6% of the RC on plastic net or wire mesh, respectively). Gnawing stick presence increased slaughter yield (59.0 vs 58.3%; P <0.05), RC weight (1266 vs 1236 g; P <0.05) and the forepart/RC ratio (29.6 vs 29.2% RC; P <0.05) while significantly reducing the meat colour b⁎ value and increasing m. Longissimus dorsi shear force (0.60 vs 0.50 kg/cm2; P <0.01). The hind leg meat fatty acid profile was only slightly influenced by experimental factors. Although this study showed pair caged rabbits to have increased carcass weight with better meatiness and other meat quality traits, hind leg bone strength was shown to be higher in pen housed rabbits. [Copyright &y& Elsevier]

Abstract: In a 2×2×2 factorial experiment the effects of housing system (pair caged (cage): 2 rabbits/0.122 m2 vs open top pen housed (pen): 13 rabbits/0.86 m2; same stocking density), floor type (wire mesh vs plastic net) and environmental enrichment (with vs without gnawing stick) were studied on live performance, health status and welfare (ear lesions) of growing rabbits (n =176). The housing system significantly influenced the body weight at 11 weeks of age (2630 vs 2557 g; in cage or pen, respectively) and the feed conversion (3.12 vs 3.38 g/g; in cage or pen, respectively). Floor type did not affect the traits tested. Gnawing stick consumption affected the body weight at 11 weeks of age (2553 vs 2622 g; without or with gnawing stick, respectively), the percentage of ear lesions (18.5 vs 1.20%; without or with gnawing stick, respectively). Some of the live performance traits of rabbits reared in pens was slightly lower. The presence of gnawing stick, especially in pens, reduced the aggressive behaviour and improved the welfare. [Copyright &y& Elsevier]

Abstract: The objective of the study was to determine the effect of birth weight and the influence of nutrient supply during nursing and after weaning on the performance of suckling and growing rabbits (n =182). The experiment was set-up using a 3×2×2 factorial arrangement. Newborn female rabbits were divided on the basis of their birth weight in 3 classes: low /L/=35–45g, medium /M/=53–58g and high /H/=65–70g. Half of the litters were nursed by one (O) doe and the other half by two does (T). Kits were weaned at 3weeks of age. From the age of 4weeks half of the rabbits were fed ad libitum (AL), while the other half were reared on a restricted feeding regime (R) corresponding to 80–85% of the ad libitum feed intake level. Birth weight had a significant effect on the body weight up to the end of the experiment (18weeks of age). H kits attained higher body weight at all ages (3772g at 18weeks of age compared to 3565g and 3373g for L and M rabbits, respectively). Significant differences were found in feed intake between 3 and 15weeks of age, in feed conversion between 9 and 12weeks of age and in weight gain between 3 and 4 and 12 and 15weeks of age, in the majority of cases in favour of the H rabbits. Nursing by one or two does exerted the most pronounced effect on the body weight. T kits had significantly higher body weight than O kits up to 15weeks of age (3306 vs. 3108g). Differences in feed intake, feed conversion and body weight were only periodically demonstrable between the groups O and T. The feeding regime exerted a significant influence on the feed intake, weight gain and body weight of kits. Significant differences in the feed conversion were found, however, only between 15 and 18weeks of age. Although AL rabbits achieved better feed conversion at all ages except the period between 9 and 12weeks of age. It seems that the three factors (birth weight, number of nursing does and feeding regime), especially the feed restriction, could influence the production of does. [Copyright &y& Elsevier]