Effect of feeding diets containing barley, wheat and corn distillers dried grains with solubles on carcass traits and meat quality in growing rabbits

The impact of incorporating dried cafeteria leftover food on growing APRI rabbits productivity, profitability and meat quality

This study was conducted to investigate the effect of dried cafeteria leftover food (DCLF) incorporation in growing APRI rabbit diets on nutrient digestibility, live body weight, body weight gain, carcass traits, meat quality, blood parameters, and economic efficiency. Thirty-six APRI rabbits (6 weeks of age), after weaning, were randomly divided into three groups (12 rabbits/group, 613 ± 5 g). During the experiment, rabbits aged 6-14 weeks participated in the experiment. An approximate isocaloric and isonitrogenous composition was achieved in three pelleted experimental diets. For the rabbit groups D1 (as the control), D2, and D3, DCLF was added at doses of 0%, 17.5%, and 35%, respectively. Digestibility trails were carried out at the end of the feeding experiment to evaluate the nutritional and feeding values of the experimental diets. To examine the characteristics of the carcasses, the quality of the meat, the histopathological analysis, and the blood plasma parameters, three rabbits were slaughtered from each group. The results showed that the feeding values (TDN and DE), which had the greatest values, as well as the digesting coefficients for dry matter, organic matter, crude fiber, and ether extract between the D1 and D3 groups were significantly different (p < 0.05). On the contrary, the curde protein, nitrogen-free extract, and digestible crude protein of the examined diets showed no signifcant differences compared with the control diet. The level of DCLF incorporation in diets significantly (p < 0.05) increased the live body weight at 14 weeks; with D3 recording the highest values (2130.9 g) when compared to the D1 and D2 groups. A similar pattern was observed for both daily increase and total body gain (6-14 weeks). Feed conversion recorded insignificant differences among the experimental diets respecting the period 6-14 weeks of age. DCLF levels had a significant effect on dressing and giblet percentages. The chemical composition and color parameters of rabbit meat were similar (p > 0.05), except for fat%, which had the highest value in the D3 group (p < 0.05) compared to the D1 and D2 groups. Economic efficiency was improved by using DLCF up to 35% in terms of gross margin and feed cost/kg gain. In conclusion, using DCLF in the feeding system of rabbits could enhance productive performance, carcass traits, meat quality, and physiological function, as well as improve economic efficiency.

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.

Performance and nutrigenomics modulations in response to the inclusion of biologically treated date-palm mulch and enzyme mixture in the diets of growing rabbits

This study was conducted to evaluate the effects of Allzyme addition on biologically-treated date-palm mulch (DPM) based diets for growing rabbits. DPM was treated by Trichoderma viride, Trichoderma reesi 230, Plorotus oysterous, and Phanaerochyte chrysosporium. Eighty rabbits were assigned to four groups: a control group, tDPM (10% tDPM inclusion of total diet), Allzyme (Allzyme supplementation), and tDPM + Allzyme (tDPM and Allzyme supplementation). The biological treatment resulted in a significant increase in crude protein and reductions in crude fiber. There was an interaction between tDPM and Allzyme at 9- and 10-week BW. The negative effects of tDPM on BW started at 8-week of age. The tDPM had unfavorable effects on slaughter and meat quality traits. The tDPM-by-Allzyme interaction affected total protein and globulin concentrations. However, blood glucose concentration was influenced by both tDPM and Allzyme. A significant tDPM effect was detected on the expression of INSR, GHSR, and IGF1 genes. However, the Allzyme effect was significant for PPARg and FASN genes. In conclusion, feeding tDPM negatively impacted rabbit's performance, however, Allzyme supplementation alleviated some of those effects. Accordingly, tDPM is recommended to be included in the diets of growing rabbits along with Allzyme supplementation.

On-Farm and Processing Factors Affecting Rabbit Carcass and Meat Quality Attributes

Rabbit meat has high nutritional and dietetic characteristics, but its consumption rate is comparatively lower than other meat types. The nutritional profile of rabbit meat, by comparison with beef, pork, and poultry, is attributed to relatively higher proportions of n-3 fatty acids and low amounts of intramuscular fat, cholesterol, and sodium, indicating its consumption may provide health benefits to consumers. But, the quality attributes of rabbit meat can be originated from different factors such as genetics, environment, diet, rearing system, pre-, peri-, and post-slaughter conditions, and others. Different rabbit breeds and the anatomical location of muscles may also affect the nutritional profile and physicochemical properties of rabbit meat. However, adequate information about the effect of those two factors on rabbit meat is limited. Therefore, cumulative information on nutritional composition and carcass and meat quality attributes of rabbit meat in terms of different breeds and muscle types and associated factors is more important for the production and processing of rabbits. Moreover, some studies reported that rabbit meat proteins exhibited angiotensin-converting enzyme inhibitory characteristics and antioxidant properties. The aim of this review is to elucidate the determinants of rabbit meat quality of different breeds and its influencing factors. In addition, the proven biological activities of rabbit meat are introduced to ensure consumer satisfaction.

Dietary utilization of mealworm frass in rabbit feeding regimes and its effect on growth, carcass characteristics, and meat quality

This study aimed to shed light on the use of mealworm (Tenebrio molitor) frass (TMF) in rabbit diets and its effects on growth performance, blood profiles, rabbit meat quality, and fatty acid profiles. A total of 48 Gabali rabbits were divided equally and randomly into four groups to be fed one of four dietary treatments: a control (T0) group and three TMF groups, which included TMF meal at 1 (T1), 2 (T2), and 3 (T3) %, respectively. The rabbits were fed on isonitrogenous and isoenergetic diets for 11 weeks, and the growth performance data were recorded. Six rabbits per group were slaughtered at the end of the 11th week, then the pharmacochemical parameters and carcass traits were measured, and meat quality and fatty acid profiles were analyzed. The results indicated that the growth performance of different groups was similar (P > 0.05). The levels of globulin, glucose, and alanine transaminase (ALT) were lower in the mealworm frass groups compared with the control group. Carcass traits were not affected by experimental regimes. Fat was higher in the TMF treatment groups, while moisture was lower compared with the control group. The shear force had a lower value in the treatment groups T3 and T2 compared with the control group. The highest values of redness and chroma (color parameter) of rabbit meat were observed in the treatment groups vs. the control group. Moreover, the proportion of total saturated fatty acids in the meat of rabbits that were fed on the T2 and T3 diets was higher compared to those fed on the control (i.e., T0) and T1 diets. Furthermore, the proportion of monounsaturated fatty acid was higher in the T2, T3, and T1 groups vs. T0 rabbits, whereas the PUFA proportions were lower. It could be concluded that frass has great potential to be used as a partial substitute for rabbit diets.

Effects of edible chitosan coating containing Salvia rosmarinus essential oil on quality characteristics and shelf life extension of rabbit meat during chilled storage

Rabbit meat is one of the most consumed meats throughout the world and is extremely susceptible to spoilage due to its high protein and moisture content. Natural preservatives with antioxidant and antibacterial properties are needed to maintain meat quality and increase its shelf life. This study examined the effect of 1% chitosan (CH), 0.2% rosemary (Salvia rosmarinus) essential oil (REO), and their combination on pH, total volatile basic nitrogen (TVB-N) and thiobarbituric acid (TBA) levels, and the microbial profile of rabbit meat stored over 12 days at 4 °C. During this time, changes in appearance, odor, and texture were also noted. The shelf lives of samples treated with only 1% CH coating, or in combination with 0.2% REO, were longer than those of untreated samples. These results showed that samples treated with both CH and REO were still acceptable until the 12th day and resulted in significantly lower meat demerit scores in these treated groups compared with untreated meat. In all groups, the pH, TVB-N, and TBA values increased over time, but these values were significantly higher (p < 0.05) in untreated samples. Microbial analysis results showed that chilled rabbit meat samples treated with combined 1% CH and 0.2% REO reduced Enterobacteriaceae, Pseudomonas, and Psychrotrophic counts. The experimental results demonstrated that using CH coating in combination with REO improved the quality of rabbit meat and could be an effective approach to reduce rabbit meat deterioration during chilled storage.

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 a cauliflower (Brassica oleraceae var. Botrytis) leaf powder-enriched diet on performance, carcass and meat characteristics of growing rabbit

The aim of this study was to investigate the effect of a cauliflower leaf powder (CLP)-enriched diet on the performance, quality and antioxidative potential of rabbit meat. No significant differences were found for live performance parameters between rabbits fed with standard (SD) and CLP diet. Dietary supplementation influenced the meat traits of rabbits: CLP meat showed significantly lower drip loss after 48 h, cooking loss, and a significantly higher lightness (L*) and redness (a*) values, vitamin A and vitamin E content, and oxidative stability, compared to SD meat. Moreover, the CLP supplementation caused a significant decrease in SFA and increase in PUFA percentage of rabbit intramuscular fat. The statistical analysis also showed a significant effect of dietary fortification on phenolic content and antioxidant activity of rabbit meat which resulted higher in meat of CLP group. This study highlighted that dietary fortification with CLP is a valid strategy to produce rabbit meat with better technological and functional quality.

Relative growth in rabbits: the effects of genetic line, diet and gender

<p>The relative growth of different parts of the body and tissues was analysed using an allometric model. Animals were crossbred rabbits (males and females) from the mating of commercial lines HYLA-grand parental doe (HY-GPD) female with HYLA Coloured (HY-CO) or Grimaud (GR) males, both selected for the growth rate, or HY-GPD males, selected for weaning weight. They were fed on two different diet, mainly differing in their energy content, and the relative growth of the different parts of their body was assessed. The components with a nearly isometric growth pattern, which grew at the same mean rate as the rest of the body, were skin, chilled carcass and reference carcass; hind legs for retail cuts; and dorsal and carcass length for linear measurements. All allometric coefficients were calculated with respect to the slaughter weight, except percentage of hind leg inter-intramuscular fat (IIMF), which was calculated with respect to the weight of the hind leg. The components that showed early maturing were liver, kidneys, breast and rib viscera for offal and organs; head and breast and ribs for retail cuts; and bone and IIMF percentage of the hind leg. The components with late maturing were forelegs and loin for retail cuts, inguinal, scapular and perirenal fat, meat of the hind leg, and thigh and lumbar circumference length for carcass linear measurements. The GR line showed earlier growth for loin than the maternal HY-GPD line. In addition, the GR and HY-CO lines developed scapular and inguinal fat later than the HY-GPD line. For IIMF percentage, GR presented later growth than HY-CO and HY-GPD. The main effect of the diet was on liver development and on scapular fat: rabbits fed on the high-energy diet showed later liver and scapular fat growth.</p>

Effects of corn dried distillers' grains with solubles on performance, egg quality, yolk fatty acid composition and oxidative status in laying ducks

The study investigated the effects of increasing content of corn distillers' dried grains with solubles (DDGS) in the diets of laying ducks on oxidative status, laying performance, egg quality, and egg yolk fatty acid composition. Longyan females (1080) with similar BW at 17 wk of age were randomly assigned to 6 treatment groups, each consisting of 6 replicates of 30 birds. The basal diet (I) was a typical corn-soybean ration while the experimental diets (II to VI) substituted corn DDGS for soybean meal and wheat bran and a small reduction of corn. The level of substitution in diets (II to VI) was 6%, 12%, 18%, 24% and 30%. The experiment lasted for 18 wk. Average egg weight decreased linearly as the level of corn DDGS inclusion increased (P < 0.001). Haugh unit, albumen weight, and proportion declined as linear responses to corn DDGS substitution (P < 0.05), but yolk color linearly increased (P < 0.001); the proportions of oleic (C18:1) and total monounsaturated fatty acids in egg yolk linearly decreased with increasing corn DDGS and many of the key polyunsaturated fatty acids (PUFAs) like linoleic (C18:2n-6), arachidonic (C20:4n-6) and α-linolenic (C18:3n-3) acids linearly increased (P < 0.001), but not those of eicosapentaenoic (C20:5n-3) and docoshexaenoic (C22:6n-3) acids. The PUFAs n-6/n-3 ratio linearly increased with increasing corn DDGS level (P < 0.001). Increasing corn DDGS linearly increased hepatic expression of GPX1, HO-1, and Nrf2 and hepatic activity of GSH-Px and the liver content of MDA (P < 0.001). There were no treatment effects on egg production, egg mass, feed conversion ratio, eggshell thickness, strength, and yolk cholesterol content (P > 0.05). In conclusion, the current study indicates that the use of corn DDGS is possible as a replacement, primarily for soybean meal at levels up to 18% in the diets of laying ducks without affecting laying performance, egg quality, and antioxidant status. Increasing amounts of corn DDGS linearly increased egg yolk concentrations of key fatty acids like like C18:2n-6 and C18:3n-3 and the antioxidant enzyme activity of GSH-Px through the Nrf2 pathway to avoid oxidative stress.

The effects of hydrolysed sorghum on growth performance and meat quality of rabbits

<p class="Articletitle">The effect of sorghum hydrolysed by <em>Trametes maxima</em> CU1 and <em>Pycnoporus sanguineus</em> CS2 was evaluated on growth performance traits and rabbit meat quality. A total of 24 unsexed New Zealand rabbits, weaned at 20 d of age, were allocated to 2 treatments: T1 (diet including 300 g/kg of non-hydrolysed sorghum) and T2 (diet including 300 g/kg of hydrolysed sorghum by <em>Trametes maxima</em> CU1 and <em>Pycnoporus sanguineus</em> CS2). Rabbits of group T2 did not have significantly different (<em>P</em>&gt;0.05) feed intake compared to those in T1. Carcass traits were also not significantly different (<em>P</em>&gt;0.05) between the 2 groups. The pH, water-holding capacity, colour and cooking loss of the longissimus lumborum were not different (<em>P</em>&gt;0.05) between treatments, whereas the pH of the rabbits biceps femoris was higher in T2 (6.21; <em>P</em>&lt;0.05) than in T1 (6.14). Meat hardness and gumminess in T2 were lower (<em>P</em>&lt;0.05) in comparison to meat from T1. Thus, sorghum hydrolysed by <em>Trametes maxima</em> CU1 and <em>Pycnoporus sanguineus</em> CS2 contributed to a better rabbit meat texture.</p>

Growth performance, carcass traits and meat quality of yellow-feathered broilers fed graded levels of alfalfa meal with or without wheat

The effects of 0, 40 and 80 g/kg alfalfa meal on growth performance, carcass traits and meat quality of Chinese yellow-feathered broilers fed diets containing or lacking wheat (0 or 200 g/kg) as part of the energy source, were examined using random design with a 2 × 3 factorial arrangement of treatments. Dressing percentage and semi-eviscerated proportion were lower, and meat color a* (redness) value was higher in birds fed diets containing wheat than diets lacking wheat (P < 0.05). Drip loss was reduced by the addition of alfalfa meal to diets containing or lacking wheat (P < 0.05). Average sensory score of breast meat was higher in chickens fed corn-based diets than in those fed wheat (P < 0.05). Meat from those supplemented with 40 g/kg alfalfa meal had better taste than the other two levels (P < 0.05). The inclusion of wheat significantly reduced the activities of creatine kinase and calpain of breast muscle (P < 0.05). In conclusion, Chinese yellow-feathered broilers fed diets containing wheat had better meat color and lower drip loss than those fed the diets without wheat, and adding 40 g/kg alfalfa meal generally improved meat quality and taste.