Influence of the genetic origin and sex on live performance and carcass traits in the rabbit. Preliminary results

The study compared the growth performance and carcass traits of 41 rabbits of both sexes derived from 3 genetic origins (GO): sire Vienna Blue (B), sire Burgundy Fawn (F) and hybrid rabbits (H). From weaning they were reared indoor in bicellular cages and fed ad libitum the same pelleted diet until a fixed slaughter weight (2.8±0.11kg). The rabbits of the 3 GO differed in slaughter age (88 vs 109 vs 122d for H, B and F-GO, respectively; P<0.001). Growth performance of B was better than that of F, while that of H was better than B+F groups. Carcass traits were not modified by the GO; only perirenal fat percentage increased from H (1.2%) to B (1.7%) to F (2.5% of the reference carcass; P<0.05) accordingly to the slaughter age. The sex effect was significant only for the dressing out percentage, being higher in males than females (59.0 vs 57.6%; P<0.05)

Do insects as feed ingredient affect meat quality?

 The development of sustainable feed ingredients for monogastric livestock is nowadays considering insect meals and oils to replace or supplement conventional feedstuffs. Although the regulation on the use of insect products differs among  countries resulting in restrictions on use in the diets of  monogastric meat producers, global research is exploring all the  strengths and weaknesses of their inclusion. Therefore, whereas  the scientific literature has extensively studied both the  relationship between insect farming systems and safety (potential health risks), and between the dietary use of insects  and the nutritional value of diets and production performance of farm animals (fish, poultry, swine, rabbit), the relationship  between insect-containing diet and meat quality has only recently been considered. The present review therefore aims to  collect the results of the studies that have related the dietary use of some insect species, such as the black soldier fly (Hermetia  illucens), the yellow mealworm (Tenebrio molitor) and the silkworm (Bombyx mori), on the physicochemical and sensory  traits of the poultry, swine and rabbit meat. The variable that has been most affected by the inclusion of insects as feed on  livestock meat quality is the fatty acid (FA) profile, which, as is well known, in monogastrics tends to reflect that of the diet.  Therefore, the black soldier fly inclusion has always originated meats with a more saturated FA profile, the yellow mealworm a  more monounsaturated fatty acid profile, whereas the silkworm a more unsaturated fatty acid profile and rich of valuable  omega-3 FA, but rarely changed the related physicochemical  variables, or the sensory profile of the meat.

rabbit farming for meat purposes

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Influence of the paternal genetic origin and season on the live performances and the carcass yield of rabbits reared in the organic production system

Organic rabbit production (ORP) must follow the guidelines for organic livestock system (EC regulation 1804/1999) but they give very few indications for rabbit rearing. In Italy, two organisms of certification (ICEA, AIAB) provide respectively the control system and the guidelines for the rabbit reared under organic system. Regarding to the breed, only pure breeds and their crosses of first generation must be used; the red-eyes breeds are forbidden. The choice of the breed must consider mainly their resistance to disease, their rusticity and slow growth. The latest rule is needed because of the rabbits must be slaughtered when reaching the 14th wk of age. In Italy, the ORP is just developing so, the permitted breeds are not yet selected for carcass and meat quality. Among the adoptable breeds, Vienna Blue and Burgundy Fawn are those the more profitable for the ORP. The aim of this study was to compare the live performance and the carcass yield of rabbits derived from two sire genetic origins, Vienna Blue and Burgundy Fawn, reared in organic system and under different rearing season

Influence of rabbit sire genetic origin, season of birth and parity order on doe and litter performance in an organic production system

The aim of this study was to compare both the performance of litters derived from two sire genetic origins (SGO), Vienna Blue (VB) and Burgundy Fawn (BF), along successive seasons of birth (SB; winter, spring, summer and autumn), and doe reproductive performance in an organic production system. A total of fifty-eight does consisting of a mixture of crosses of several medium-large size breeds at different parity order (P, 1 = nulliparous; 2 = primiparous; 3 = multiparous) and twelve males (6 VB and 6 BF) were housed indoor at environmental conditions that followed seasonality. An extensive reproductive rhythm was used and kits were weaned at 466 d of age. Doe reproductive performance and the data of 105 litters (55 from VB and 50 from BF SGO) were recorded throughout the SB. No statistically significant differences related to SGO effect were observed. As regards parity order, multiparous does showed higher live weights (LW) (p<0.05), total born (p<0.01), total born alive (p<0.05) per delivery, and litter weight of born alive (p<0.05), but lower milk output at 21st d than primiparous does (p<0.05). The extensive reproductive rhythm mainly increased litter performance at birth in multiparous does but was not sufficient to permit a complete recovery of body reserves lost during lactation. Autumn SB negatively affected doe LW variation between deliveries. The number of pups born and born alive per delivery (p<0.05) and litter size at 21 d of age and at weaning (p<0.01) were lower during hot SB. Due to the lower litter size of pups born in summer and autumn, their individual weight at 21st d of age and daily individual growth rate 0 to 21 d were higher than those of pups born in winter (p<0.001). Litter performance at 21st d of age and individual pup pre-weaning growth rate were poorer for those born in spring than in other seasons due to the suffering caused by the effects of increased environmental temperatures. SB affected most of the performance traits of does and young rabbits reared under the organic farming system. The rabbits seemed better suited to organic rearing conditions during winter than in other seasons. The worst results overall were obtained in the spring SB, whereas the hot SB negatively affected both doe energy balance and prolificacy. In conclusion, the pups of the 2 SGO showed good pre-weaning performance and seemed suited to the organic rabbit production system

Dietary inclusion of tannin extract from red quebracho trees (Schinopsis spp.) in the rabbit meat production

Two levels (1% and 3%) of condensed tannin extract from red quebracho (QT) were added to a diet of growing rabbits in a 6-wk feeding trial up to 12 wk of age. Health status was unaf- fected by the QT supplementation. The E. coli count of caecal content denoted a bactericidal activity of the QT. Weight gain and slaughter weigh were significantly higher and conversion index was sig- nificantly lower in rabbits fed QT diets, compared to those fed the control diet (P<0.05). Meat traits, as well the meat fatty acid profile weren't influenced by the QT supplementation. Our results contributed to increase the knowledge on the dietary use of QT in the rabbit. QT extract supplemented at 1% and 3% in fattening rabbits diet had a clear beneficial effect on live performance. Further studies are needed to assess if supplementing diets with QT can be a valuable strategy

The dietary inclusion of Portulaca oleracea to the diet of laying hens increases the n-3 fatty acids content and reduces the cholesterol content in the egg yolk

The effect of n-3 polyunsaturated fatty acids (PUFA)-enriched diet on yolk fatty acid profile and cholesterol content was evaluated. Dried Poutulaca oleracea (purslane: PO diet) was added to a commercial diet (C diet) at 20% of inclusion level. The effect of the supplemented diet was compared to that of C diet. Twenty-six laying hens were fed ad libitum for 21 days with the 2 diets, supplemented also with 300 mg α-tocopherol acetate/kg. Eggs were collected and then the fatty acids (FA) profile and the cholesterol content were analysed. The PO diet significantly reduced the saturated FA content (P<0.05) and increased that of the polyunsaturated FA (PUFA): 18:2 n-6 (P<0.001), 18:3 n-3 (P<0.001) and 22:6 n-3 (DHA; P<0.01). Both n-6 and n-3 PUFA significantly increased with the PO diet and the n-6/n-3 ratio was improved (10.4 vs 11.3; P<0.05)

Fat inclusion level, NaCl content and lab starter cultures in the manufacturing of Italian-type ostrich Salami: Weight loss and nutritional traits \u2020

The experiment studied the effect of two different fat inclusion levels (30% and 40%), NaCl contents (2.4 and 2.6%) and starter cultures (lactic acid bacteria (LAB) 6: L. curvatus/S. xylosus; LAB 8: L. sakei/S. xylosus) on the weight loss and nutritional composition of Italian-type ostrich salami. With this purpose, 8 batches of 9 salami each (n = 72) were prepared. Salami were ripened for 20 weeks: weight loss was monitored throughout the experiment, while salami nutritional composition was evaluated at 10 and 20 weeks of ripening. The lowest fat and highest salt inclusion levels provided the highest cumulative weight loss throughout the trial. At 10 weeks of ripening, salami with 40% fat were the richest in moisture and fat, whereas the leanest ones had the highest protein, ash and cholesterol contents. LAB 6 provided salami with the highest moisture and protein, while LAB 8 increased fat and cholesterol contents. At 20 weeks of ripening the proximate composition of ostrich salami was solely affected by fat inclusion level, with similar findings to those observed at 10 weeks. Overall, fat inclusion level had a great impact on the weight loss and nutritional composition of Italian-style ostrich salami. Reducing the NaCl inclusion from 2.6% to 2.4%, the weight loss of ostrich salami was retarded by approximately 1 week, without affecting the nutritional composition of the final product. Results of the study suggested that it is feasible to produce salami with lower fat and salt contents, while ensuring satisfactory product quality

Meat quality of male and female Italian Padovana and Polverara slow-growing chicken breeds

The study characterised and compared proximate composition and fatty acid (FA) profile of breast and leg meat of chickens belonging to Padovana and Polverara Italian local breeds. Birds were slaughtered at 183 days of age and four experimental groups were formed: Padovana males (PAD M), Padovana females (PAD F), Polverara males (POL M) and Polverara females (POL F). Proximate composition was assessed on 10 breasts and 10 legs per group, whereas FA profile and cholesterol content were assessed on six samples per cut per group. Breast meat proximate composition resulted in similarity between the two genotypes and sexes. Genotype did not affect breast FA profile except for C18:1 n-11, whereas females breast meat was richer in DHA (p < .05) and thus in n-3 (p < .05). Leg meat exhibited greater variability due to genotype and sex. Indeed, PAD chicken legs were richer in dry matter (p < .01), lipids (p < .01) and cholesterol (p < .01) than POL. It emerged that leg meat from PAD breed was characterised by a more desirable FA profile due to its higher UFA:SFA (p < .05) and lower n–6/n–3 (p < .05) ratios. Despite exhibiting a lower PUFA:SFA ratio than males (p < .05), females exhibited a better n–6/n–3 ratio (p < .01). The two genotypes and the two sexes possess peculiar nutritional quality. The aim of this study was to create economic interest around these local productions to assure their survival.Highlights Padovana and Polverara are two rustic slow-growing chicken breeds which are farmed in the Veneto region of Italy. The goal of the present study is contributing to the creation of economic interest around local productions from Padovana and Polverara chickens. Creating an economic interest around Padovana and Polverara breeds would contribute to the preservation of local tradition and rural culture