Carcass characteristics and meat quality of rabbit lines selected for different objectives:

Dietary Supplementation of Microalgae and/or Nanominerals Mitigate the Negative Effects of Heat Stress in Growing Rabbits

Heat stress (HS) is one of the most significant environmental factors that result in fluctuations and shrinkage in rabbit growth, health, and overall productivity. This study aims to investigate the effects of dietary mineral nanoparticles (selenium or zinc) and/or Spirulina platensis (SP) independently and in combination on stressed growing rabbits. A total of 180 weaned growing New Zealand White rabbits were included in this study and randomly divided into six dietary treatments. Rabbits received a basal diet (control group; CON group) or fortified with SP (1 g/kg diet), selenium nanoparticles (SeNPs, 50 mg/kg diet), zinc nanoparticles (ZnNPs, 100 mg/kg diet), and a mixture of SP and SeNPs (SPSeNPs) or SP and ZnNPs (SPZnNPs) groups for 8 weeks during summer conditions. The obtained results demonstrated a significant increase in the final body weight and weight gain (p < 0.05). Additionally, the feed conversion ratio was improved during the periods from 6 to 14 weeks in the treated rabbits compared to those in the CON group. Dietary supplements considerably improved (p < 0.05) the blood hematology (WBCs, Hb, RBCs, and Hct) and some carcass traits (liver weights and edible giblets). All dietary supplements significantly decreased serum levels of total glycerides (p < 0.0001), AST (p = 0.0113), ALT (p = 0.0013), creatinine (p = 0.0009), and uric acid (p = 0.0035) compared to the CON group. All treated groups (except ZnNPs) had lower values of total bilirubin and indirect bilirubin in a dose-dependent way when compared to the CON group. The values of IgA, IgG, and superoxide dismutase were significantly improved (p < 0.05) in all treated rabbits compared to the CON group. Compared with the CON group, the levels of T3 (p < 0.05) were significantly increased in all treated growing rabbits (except for the ZnNP group), while the serum cortisol, interferon-gamma (IFN-γ), malondialdehyde, and protein carbonyl were significantly decreased in the treated groups (p < 0.05). Dietary supplements sustained the changes in hepatic, renal, and cardiac impairments induced by HS in growing rabbits. Adding SP (1 g/kg diet) or SeNPs (50 mg/kg diet) in the diet, either individually or in combination, improved growth performance, blood picture, and immunity-antioxidant responses in stressed rabbits. Overall, these feed additives (SP, SeNPs, or their mixture) can be applied as an effective nutritional tool to reduce negative impacts of summer stress conditions, thereby maintaining the health status and improving the heat tolerance in growing rabbits.

Physicochemical properties and sensory profile of some breeds of rabbits in Algeria

The objective of this study was to compare physicochemical traits and sensory profile of meat from rabbits of both sexes belonging to two genotypes, local population and new line (ITELV 2006) which exhibited better characteristics due to its genetic potential. A total of 60 rabbits at 90 days of age were used in the experiment. At slaughter, meat physicochemical and sensory characteristics were measured on Longissimus lumborum muscle. Differences related to genotype were found in most of the physicochemical characteristics studied like Cooking Losses (P < 0.001), Percentage of Released Water (P < 0.001), Myofibril Fragmentation Index (P < 0.001) and a* value (P < 0.001). However, in some of the traits, the differences were related to interaction of sex and genotype (S*G) as in the case of Cooking Losses (P < 0.001) and b* value (P < 0.01). Regarding SDS-PAGE analysis results, the comparison between two breeds has not shown any particular distinction in the myofibrillar and sarcoplasmic protein profiles in relation to the number and the intensity of bands. No significant differences in the sensory characteristics of the meat were noted (P > 0.05). Interestingly, no relevant differences were found between meat from male and female rabbits in all the variables studied (P > 0.05). It was concluded that meat quality was mainly affected by genotype. Thus, the new line exhibited good physicochemical characteristics compared to the local one. This study is the first to analyse and compare the physicochemical and sensory properties of Algerian rabbit meat.

Physiological and immunological aspects of feed restriction and its beneficial impacts in fattening rabbits' productivity-an updated review

Two feed restriction (FR) regimens are utilized with weaned rabbits including a quantitative FR (amount-limited feed or time-restricted admission to feed) and a qualitative FR (modulation of diet content especially protein and energy). The use of post-weaning FR may help in preventing post-weaning digestive disorders, stimulating compensating growth, improving feed efficiency, and decreasing carcass fat content. Interestingly, FR may contribute to changing meat's chemical composition and its physical quality attributes by regulating the morphological and biochemical characteristics of muscle fibers. Also, FR could enhance the gastrointestinal tract development, its histomorphology, and improve feed digestibility and absorption. Furthermore, FR regimens are involved in establishing gut microbial balance and enhancing the host immunological response. It might be concluded that post-weaning FR is involved in influencing the physiological and immunological aspects of growing rabbits. It might be documented that light to mild FR (i.e., 80-90% AL), early (i.e., at the first 2 weeks post-weaning), and relatively short in duration (i.e., for 2-3 weeks) had no negative effects on live body weight, while severing FR reduced live body weight in comparison with ad libitum rabbits.

Growth Performance, Digestive Efficiency, and Meat Quality of Two Commercial Crossbred Rabbits Fed Diets Differing in Energy and Protein Levels

The present study evaluated the effect of digestible energy (DE) and crude protein (CP) levels on growth, digestive efficiency, slaughter yield and meat quality in growing rabbits of two genotypes (Grimaud, G vs. Hyla, H). A total of 384 crossbred rabbits (192 G and 192 H), half males and half females, were divided into eight experimental groups according to a bi-factorial arrangement (2 genotypes × 4 diets; 48 animals/group) and reared in individual cages. From 33 to 64 days of age, rabbits were fed four diets obtained by combining two DE levels (high, HE—10.9 MJ/kg vs. low, LE—9.2 MJ/kg, on average) and two CP levels (high, HP—159 g/kg vs. low, LP—144 g/kg, on average). Then, all rabbits received the same fattening diet (10.7 MJ DE/kg; 156 g CP/kg) until slaughtering (77 days of age). Growth performance did not differ between genotypes for the entire trial (on average final live weight 3010 g; daily weight gain 50.5 g/d), but H rabbits showed a faster growth during the post-weaning period (p ≤ 0.01) compared to G rabbits, while exhibiting lower slaughter yield and lower carcass fatness (p ≤ 0.01). As DE level increased, feed intake decreased and feed conversion improved (p < 0.001), while caecal volatile fatty acid concentration increased and caecal pH and N-ammonia decreased (p ≤ 0.01). The reduction in the CP level did not affect performance and carcass traits. No significant interaction was detected between genotype and diet. In conclusion, G rabbits may have an advantage over H rabbits because of the higher slaughter yield. As for the nutritional characteristics of diets for high-producing crossbred rabbits, high energy levels are confirmed to enhance feed efficiency, whereas dietary CP can be reduced to 144 g/kg without negative effects on performance and carcass traits.

Enterocin 7420 and Sage in Rabbit Diet and Their Effect on Meat Mineral Content and Physico-Chemical Properties

Rabbit meat has outstanding nutritional characteristics—it is a lean meat with low fat, cholesterol and sodium content, with high-biological-value proteins, potassium, phosphorus, selenium, iron and vitamin B12 level. The dietary inclusion of natural bioactive compounds can improve the quality of rabbit meat. The present study evaluated the effect of enterocin 7420 (Ent 7420) and sage (Salvia officinalis) extract on the quality and mineral content of rabbit meat. A total of 96 Hyla rabbits (aged 35 days) were divided into E (Ent 7420; 50 µL/animal/d), S (sage extract; 10 µL/animal/d), E + S (Ent 7420 and sage in combination) and control (C) groups. Additives were administrated in drinking water for 21 days. A significant increase in meat iron (p < 0.01) content was noted; phosphorus and zinc levels were also elevated in experimental groups, compared with control data. Ent 7420 and sage treatment reduced the calcium and manganese (p < 0.01) contents. The physico-chemical traits of rabbit meat were not negatively influenced by treatment. Based on these results, diet supplementation, mostly with Ent 7420 but also in combination with sage, could enhance the quality of rabbit meat mineral, with a focus on its iron, phosphorus and zinc contents.

The effect of feed restriction, sex and age on the carcass composition and meat quality of nutrias (Myocastor coypus)

The objective of the study was to evaluate the effect of quantitative feed restriction on the carcass composition and physical, chemical, histochemical and sensory properties of meat from male and female nutria at the end of the feed restriction and fattening period. In the experiment, from two to eight months of age, males and females were divided into two groups: one group was fed ad libitum throughout the experiment, and the second group was restricted to two weeks (from 11 to 12 weeks of age). The restricted nutrias received 75% ad libitum feeding. The significant interaction among feed restriction, sex and age was revealed only in the cross-sectional area of all muscle fiber types. Age was the main factor affecting carcass composition and meat quality characteristics. Sex-related differences in carcass composition and some sensory attributes and feed restriction-related differences in carcass composition were observed.

Children's consumption of rabbit meat

<p>The nutritional and dietary properties of rabbit meat make it an ideal food for children, recommended by the World Health Organisation. However, the presence of children under 18 in the home has been found to decrease the frequency of rabbit meat consumption. If we focus on households with children under 18, 52.5% of minors do not consume rabbit meat. The main reason why children (intended as people under 18 yr old) do not consume rabbit meat is the fact that they do not like it (40.9%) and because it is not bought/eaten at home (30.9%). Faced with this situation, there is a pressing need to seek appropriate strategies to adapt rabbit meat for consumption by the youngest family members. In light of the results, the following strategies are proposed. First, the development of functional foods for babies and children, such as rabbit meat enriched with ω3 and docosahexaenoic acid. Secondly, improving meat tenderness. Third, adapting rabbit meat presentations for children (burgers, nuggets, sausages, marinades …), converting them into convenience products for parents and extending their shelf life. Fourth, adapting the labelling/packaging for children to attract attention of both parents and offspring. Finally, developing communication strategies on the nutritional value of rabbit meat aimed at both children and parents. It is observed that if minors consume rabbit meat, they also eat other types of meat such as lamb and beef more often. Therefore, in this type of households a varied and complete diet is consumed in terms of meat consumption, so it would be necessary to rethink joint communication strategies among the three meat sectors. Promoting rabbit meat consumption among the under 18s has several consequences, as in the future they will be in charge of household purchases or share this responsibility.</p>

The effects of dietary quercetin supplementation on the meat quality and volatile profile of rabbit meat during chilled storage

Thirty-four New Zealand White rabbits of both sexes were fed a control or supplemented (2 g/kg quercetin dihydrate) diet from weaning until slaughter (13 weeks). After post-mortem chilling, excised and minced Longissimus thoracis et lumborum muscles were stored at 3.2 °C under oxygen-permeable wrapping for 1, 3 or 5 days. Colour, pH, lipid oxidation (TBARS), antioxidant capacity (FRAP), volatile profile (day 1 and 5) and microbial count (day 5) were determined. Quercetin reduced alkane (day 5) and hexanal (day 1) concentrations, but otherwise had minimal antioxidant effect, and did not benefit microbial quality, and thus did not substantially improve the shelf-life. The sex effect was similarly limited. Overall, the pH increased and FRAP decreased during storage, but TBARS did not change and discolouration seemed delayed. The volatile profile was dominated by esters, alcohols and heterocyclic compounds, and while it changed during storage, lipid oxidation products did not increase as expected, suggesting that rabbit meat may have relatively active reducing mechanisms.

Growth performances, carcass traits, meat quality, and blood metabolic parameters in rabbits of local Algerian population and synthetic line

Aim:

The objective of this work was to study the growth performance, slaughter traits, meat quality, and metabolic profile in rabbits of local Algerian population and a synthetic line.

Materials and Methods:

In total, 120 weaned rabbits were used (60 per group). Growth traits were recorded from weaning (35 days) to slaughter (91 days). At slaughter, carcass traits, meat quality, and metabolic profiles were measured.

Results:

The synthetic line showed heavier total weight and faster daily weight gain than the local population (+15% and +19%, respectively), better feed conversion (3.92 vs. 4.81 g/g), and heavier weight of cold carcass, and perirenal fat (+15%). No differences were found between the two groups in dressing out percentage, muscular pH, weight of liver, or scapular fat. Wider intestinal villi were found in the synthetic line (+20%, p<0.0001) allowing better absorption surface in this line. The synthetic line also showed higher fat content (3.41% vs . 2.22%, p<0.0001) in the meat and lower protein content (22.02% vs . 18.98%, p=0.0002). Glucose level was 19% higher in the local population than in the synthetic line.

Conclusion:

The synthetic line is well adapted to the local conditions of Algeria. This line has shown better growth, daily gain, and feed conversion, due to its better intestinal absorption surface.

Effect of age and gender on carcass traits and meat quality of farmed brown hares

A total of 48 sub-adult hares and adult reproducing farmed hares were used to characterize carcass and meat traits according to the age and gender of animals. With respect to carcass traits, when age increased, the carcass weight significantly increased (2022 to 3391 g; P<0.001), but dressing out percentages did not change. The dissectible fat (1.3% to 2.2%; P<0.05) and Longissimus lumborum (LL) proportions (13.5% to 14.5%; P<0.001) and muscle-to-bone ratio of hind legs (5.11 to 6.23; P<0.001) increased, whereas the hind leg proportions decreased (37.3% to 36.3%; P=0.01). As for the meat quality, the pH of hind leg (5.74 to 5.83; P<0.001) and LL (5.53 to 5.69; P<0.001) increased with age, while the L* index decreased in both cuts (42.9 to 34.4 in hind leg; 45.1 to 40.3 in LL; P<0.001). The redness index increased at the hind leg (4.07 to 5.76; P<0.001), while it decreased at LL (3.03 to 1.46; P<0.001). In the case of the hind leg, meat thawing losses decreased (1.58% to 1.02%), and shear force increased (2.97 to 4.02 kg/g). In the case of LL, thawing losses decreased (8.79% to 4.91%; P<0.001) in the adult hares compared with the sub-adult ones. Meat water and protein contents decreased in the hind leg and LL of the adult hares compared with the sub-adult ones, whereas ether extract increased in a restricted range in LL only (0.92% to 1.11%; P<0.001). In the case of the hind leg, the rate of the saturated fatty acids (SFA) decreased (41.0% to 26.7%), and the rate of the polyunsaturated fatty acids (PUFA) increased (34.0% to 45.3%) (P<0.001). In the case of LL, SFA (38.6% to 42.9%) and monounsaturated fatty acids (19.4% to 27.2%) increased, whereas PUFA decreased (42.0% to 30.1%) when the age increased (P<0.001). Gender affected only the slaughter results and carcass traits. In conclusion, farmed hares have favourable slaughter results (high dressing percentage), carcass traits (high hind legs and loins rates), and meat nutritional value (high-protein, low-fat meat). This fact would offer additional commercial opportunities, in addition to restocking, to hare farmers.

Meat physical quality and muscle fibre properties of rabbit meat as affected by the sire breed, season, parity order and gender in an organic production system

<p>The aim of the study was to evaluate some meat physical quality and muscle fibre properties of rabbit meat when considering 2 sire breeds (SB: Vienna Blue [VB]; Burgundy Fawn [BF]; both coloured and slow-growing breeds), several parity orders (P: 1, 2, ≥3), gender (G), and 2 slaughter seasons (SS: spring, summer) in an organic production system. The effect of storage time (ST) at frozen state (2 mo at –20°C) of <em>Longissimus lumborum</em> (LL) meat was also evaluated. Animals were slaughtered when they reached 2.8 kg of live weight. Then, pH and L*a*b* colour values of <em>Biceps femoris</em> (BF) and LL muscles, water loss and Warner-Bratzler shear force of LL and hind leg (HL) meat, and the fibre typing and enzymatic activity of LL muscle were analysed. LL meat from females showed higher b* values than males (0.04 vs. –1.25; P&lt;0.05). Significant (P&lt;0.05) SB×P, SB×G and P×G interactions were observed for the b* value of LL: VB and BF crossbreds presented a higher b* value when born as P≥3 and P2 respectively, VB females showed higher b* value than VB males, and P2 and P≥3 produced males with a significantly lower b* value. HL thawing losses were significantly (P&lt;0.05) higher in rabbits slaughtered in summer than in those slaughtered in spring, whereas the opposite result was obtained for LL meat (P&lt;0.01). Cooking loss of LL meat was significantly lower in P2 group than P≥3 group (P&lt;0.05). The lactate dehydrogenase activity in LL muscle was higher in VB than in BF crossbreds (930 vs. 830 IU; P&lt;0.05), albeit not supported by differences in fibre type distribution. The ST significantly (P&lt;0.01) reduced pH, a* and b* colour values, and increased lightness of LL meat. It was concluded that the crossbreeds derived from VB and BF genotypes and farmed organically did not show remarkable sexual dimorphism, considering their elder slaughter age than rabbits reared under intensive conditions. Physical quality of meat was mainly affected by slaughter season, indicating that in the organic rearing system, specific attention needs to be paid to the farming environmental conditions.</p>

Comparison of productive and carcass traits and economic value of lines selected for different criteria, slaughtered at similar weights

<p>The aim of the experiment was to compare 3 genetic groups, slaughtered at similar weights, to examine their productive and carcass traits and economic value. Three lines of the Pannon Breeding Programme, selected for different criteria, were examined in the experiment. Pannon Ka (PKa, maternal line) does were inseminated with semen of PKa, Pannon White (PWhite) or Pannon Large (PLarge, terminal line) bucks. The kits (PKa×PKa, PWhite×PKa, PLarge×PKa; n=60 in each genetic group) were weaned at 35 d of age and reared until 88, 83 and 79, respectively, when they reached similar body weights for slaughtering (2.8 kg). The weight gain of PLarge×PKa was the largest (51.0 g/d) and that of PKa×PKa was the smallest (47.2 g/d), while PWhite×PKa (41.8 g/d) was intermediate (P&lt;0.001). Difference was found in feed conversion ratio between weaning and the age of slaughter  PKa×PKa: 3.03 respect to PWhite×PKa: 2.75 and PLarge×PKa: 2.66; , P&lt;0.05). Dressing out percentage and ratio of hind part to reference carcass of PWhite×PKa, PLarge×PKa and PKa×PKa were 62.4 and 37.7, 61.8 and 37.5, 61.3 and 36.8%, respectively (P&lt;0.01). Results show that PLarge×PKa rabbits were able to exceed the average economic indicators compared to other groups. It may be concluded that the production performance of growing rabbits was affected by the adult weight, but the carcass traits were influenced by the computer tomography (CT)-based selection.</p>

Dietary supplementation of a bacteriocinogenic and probiotic strain of Enterococcus faecium CCM7420 and its effect on the mineral content and quality of Musculus longissimus dorsi in rabbits

The effect of freeze-dried bacteriocinogenic and probiotic strain Enterococcus faecium CCM7420 on the mineral content and carcass quality of rabbits was investigated. Significant increase in iron content in the carcass samples was recorded during the probiotic treatment, whereas the concentrations of calcium and copper decreased in the experimental groups compared with the Control. The treatment did not have a negative influence on the pH, colour, water-holding capacity, protein and fat contents or energetic value of the rabbit carcass. Inferring from the higher iron content we conclude that the diet supplementation with bacteriocinogenic and probiotic strain E. faecium CCM7420 may enhance the mineral quality of rabbit meat.

Comparison of degrees of maturity of rabbit lines selected for different traits

<p>The aim of this work was to study whether commercial nucleus lines of rabbits selected for different traits, and experimental lines having commercial purposes, have the same degree of maturity when compared at the same slaughter age. The study was carried out with 17897 rabbits from Universitat Politècnica de València. Rabbits came from the maternal lines A (3902 rabbits; 44^th generation), V (4238 rabbits; 39^th generation) and LP (6115 rabbits; 9^th generation), selected for litter size at weaning; the paternal line R (2023 rabbits; 25^th generation), selected for growth rate between 28 and 63 days of age; the maternal line OR (586 rabbits; 11^th generation) selected for ovulation rate; and the lines High (503 rabbits; 5^th generation) and Low (530 rabbits; 5^thgeneration) lines, from a divergent selection for high and low intramuscular fat, respectively. Rabbits were weighted at 28 (W28) and 63 (W63) days of age. Rabbit does (42, 25, 39, 94, 14, 32 and 22 from lines A, V, R, LP, OR, High and Low, respectively) were weighed between 30 and 80 wk of age to determine adult weight (AW). Line R had higher W28 and W63, growth rate between 28 and 63 d of age and AW than lines A, V and LP (5802 g vs. 4410, 4222, and 4391 g for AW, respectively). No relevant differences between lines in degrees of maturity at 28 and 63 d of age and time to reach 40% of degree of maturity (percentage of weight compared to AW) were found between lines A, V, R and LP, but the degree of maturity at 2000 g and the time taken to reach that weight were lower in line R (34.7% and 55.2 d) than in lines A (45.5% and 71.1 d), V (47.4% and 69.6 d), and LP (45.8% and 68.0 d). No relevant differences were found between lines OR, High and Low in the traits analysed. A robustness analysis showed that results can be extrapolated to other commercial lines and other slaughter weights. In conclusion, comparison of lines at similar slaughter age could be considered a valid approach for comparisons at the same maturity stage.</p>

Quality of meat of rabbits after application of epicatechin and patulin

The aim of the present study was to determinate the effect of epicatechin and patulin on selected parameters of meat quality of rabbits. Adult female rabbits (n=25), maternal albinotic line (crossbreed Newzealand white, Buskat rabbit, French silver) and paternal acromalictic line (crossbreed Nitra's rabbit, Californian rabbit, Big light silver) were used in experiment. Animals were divided into five groups: control group (C) and experimental groups E1, E2, E3, and E4. Animals from experimental groups E1, E2, E3, E4 received patulin through intramuscular injection (10 µg.kg-1) twice a week and animals from groups E2, E3, E4 received epicatechin three times a week through intramuscular injection. After 30 days animals were slaughtered. For analysing of meat quality the samples of Musculus longissimus dorsi (50 g) were used. Application of  epicatechin and patulin to rabbits had slight or no effect on the pH levels in stomach, small intestine, large intestine and urinary bladder contents, however differences among the groups were insignificant (p ˃0.05). Application of epicatechin and patulin to rabbits had slight or no effect on total water, protein, fat   and differences among the groups were insignificant (p >0.05). The values of amino acids concentrations were not influenced after application of epicatechin and patulin. The fatty acid profiles in animals after application of different doses of epicatechin and 10 µg.kg-1 patulin were similar (p >0.05). Concentration of cholesterol increased in experimental groups in comparison with the control group, but differences were insignificant (p >0.05). pH levels of meat of rabbits in experimental group E3 was lower when compared with the control group, but differences was not significant (p >0.05).  Electric conductivity parameter was increased in each experimental group (in E3 the highest) against the control but without significant differences (p >0.05). Colour L parameter was slightly decreased in experimental groups with comparison to the control group (in E3 the lowest). Generally we can conclude that intramuscular application of epicatechin or patulin did not affect parameters of meat quality as well as pH values of internal organs content. Further investigations are needed to prove the final answer concerning the health promoting effects of epicatechin and patulin.

The value of in vivo real time ultrasonography in assessing loin muscularity and carcass composition of rabbits

Sixty nine growing rabbits were scanned over the lumbar region using a real time ultrasonography (RTU) machine to estimate loin muscularity and carcass composition. Longissimus thoracis et lumborum muscle (LM) depth, width and area were taken. Animals were weighed (LW), slaughtered and carcass composition was determined. Equivalent measurements to those taken by RTU in vivo were taken on the carcass and muscularity indices were calculated on carcass and in vivo. Simple correlations between the two types of measurements were determined and carcass composition was estimated by simple and multiple regressions. The LW varied from 1200 to 3410g. The simple correlations between carcass and in vivo RTU LM measurements were high (P<0.001) and the LM area was the trait with the highest correlation (r=0.92). Simple correlations between muscularity indices measured by RTU and in carcass were significant (P<0.001). In vivo RTU measurements explained a large amount of the variation of the carcass meat weight (MW) and bone weight (r(2) range from 0.49 to 0.77; P<0.001). Using multiple regression equations to estimate carcass composition, the best fit was obtained with the LW and one or more in vivo RTU measurement. The LW explained 90.6% of the variation of MW in the carcass. In vivo RTU is able to estimate loin muscularity and carcass composition of rabbits with accuracy. The usefulness of in vivo RTU and LW to predict carcass composition of rabbits using multiple regressions was also shown.

Carcass composition, bone mechanical properties, and meat quality traits in relation to growth rate in rabbits

The objective of this study was to characterize correlated responses in carcass composition, bone mechanical properties, and meat quality indicators to divergent selection for growth rate. Rabbits from low (LOW) or high (HIGH) lines divergently selected over five generations on 63-d BW and a control group (CONT) were used. Rabbits were slaughtered at an average BW of 2,306 +/- 65 g, corresponding to 63, 58, or 52 d of age in LOW (n = 41), CONT (n = 43), and HIGH (n = 44) groups, respectively. Postweaning ADG and G:F increased (P < 0.001) in the order LOW < CONT < HIGH groups. The lengths of the tibia and femur in rabbit legs decreased (P < 0.001) with increasing growth rate. Tibia and femur bone intrinsic stiffness, as assessed by a three-point flexure test, followed the order (P < 0.001) of HIGH < CONT < LOW groups. At the same BW, HIGH rabbits and CONT rabbits showed many similarities for dressing percent, carcass composition, and color and chemical composition of muscles or meat parts. In contrast, carcass yield and the relative proportion of hind part were 3% greater (P < 0.01) in LOW rabbits than in CONT and HIGH rabbits. The meat-to-bone ratio in the hind leg was 11% greater (P < 0.001) in the LOW group compared with the CONT and HIGH groups. Yellow color index and moisture content in LM, a fast-twitch glycolytic muscle, were lower (P < 0.05) in LOW rabbits than in HIGH rabbits, but ultimate pH, WHC, and cooking loss did not differ between the two growth-selected lines. Ultimate pH in semitendinosus, a mixed slow- and fast-twitch oxidoglycolytic muscle, was less (P < 0.001) in HIGH rabbits than in CONT and LOW rabbits. However, lactate dehydrogenase and isocitrate dehydrogenase activities in this muscle (n = 21 per group), assessed at the time of slaughter as markers of glycolytic and oxidative capacities, respectively, did not differ among groups. Growth rate did not modify mean cross-sectional area and type frequency of myofibers in semitendinosus muscle. Finally, Warner-Bratzler shear force and total energy needed to achieve rupture did not differ among groups in semitendinosus muscle (n = 21 per group), whereas they were the least (P < 0.001) in LM (n = 128) from HIGH rabbits. Results from this study indicate that improvement of growth rate by selection has little effect in rabbit carcass and meat quality traits.