The carcass and meat quality of three different commercial chicken genotypes reared according to the organic system and slaughtered at two different ages (70 and 81 days) were compared. The used genotypes were Naked Neck (CN1), Kabir (KR4) and Ross 308 (R). All animals were raised in the facilities of a big Italian company, in production units of 3000 birds. Before slaughtering, plumage conditions, foot pad dermatitis as well as qualitative traits of carcasses, such as skin damage and the presence of breast blisters, were registered (n=50). Naked Neck birds showed the best plumage conditions at both ages; the other genotypes had similar body conditions showing a dramatically worsening at the end of rearing cycle (81 days), mainly at breast level. The carcass conformation showed differences mainly for the CN1 genotype, which was more slender with higher proportions of head, neck and legs; thus, ready-to-cook-carcass yield was lower. The meat of CN1 chickens showed lower levels of lipids, pH and brightness values, but higher index of redness. Ross 308 genotype showed a bad welfare status even at 70 days, confirming that the rearing of this strain should not be permitted in organic systems. In conclusion, this study indicates that genotype deeply affects performance, welfare and qualitative characteristics of meat. Regarding the slaughtering age, although the inconsistency of European Commission rules which authorise the reduction of slaughtering age in less mature strains, at 70 days chickens show higher feed efficiency and thinness of carcass and meat.

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(2016) Effect of transport length on invivo oxidative status and breast meat characteristics in outdoor-reared chicken genotypes, Italian Journal of Animal Science, 15:2,[191][192][193][194][195][196][197][198][199] The aim of the study was to evaluate the effect of transport length on in vivo oxidative status and breast meat characteristics in two chicken genotypes reared under free range conditions. A total of 200 male chicks, 100 from fast-growing (Ross 308) and 100 from medium-growing (Naked Neck) strain were used. Fifty-six of these, 28 for genotype, before slaughtering, were randomly allocated to 2 pre-slaughter conditions: absence (0 h) or 4 h of transport. The transport length significantly affected the in vivo oxidative status of broiler greatly reducing the a and d-tocopherol, retinol and lutein þ zeaxanthin content of plasma, and increased the oxidative stress (thiobarbituric acid reactive substances, TBARS) in both strains. Concerning meat quality, the pH (0, 2 and 24 h post-mortem) of breast muscles of chickens transported for 4 h, showed higher values, and respect to strains, Naked Neck had lower values. The pH values were negatively correlated with the lightness (2-24 h) and the shear force of meat. The transport length significantly affected the fatty acid profile of breast muscle, with a decrease in polyunsaturated fatty acids and an increase in TBARS value. Even the antioxidants content of breast was reduced by chicken transport (a-tocotrienol, a-, d-tocopherol and lutein þ zeaxanthin), especially in Naked Neck birds. In conclusion, the results indicate that transport for 4 h prior to slaughter, negatively affect the meat quality of poultry. Slow-growing chickens seem more sensible to stress transport due to the higher kinetic behaviour of these strains. ARTICLE HISTORY

The aim of the present study was to investigate the effect of transport on welfare traits, several haematological parameters and carcase hygiene in two different chicken genotypes (fast-and slow-growing strains) reared under free-range conditions. For this aim, two hundred male chicks, 100 from fast-growing (Ross 308, R) and 100 from slow-growing (Naked Neck, NN) strain were farmed. At the end of the rearing period, at 81 days of age, 56 birds/strain were randomly selected for slaughtering and submitted to two different pre-slaughter conditions: no transport (0h) or 4 hours of transport (4h). Tonic immobility (TI), blood parameters and carcase hygiene traits were determined. Strain and transport significantly affected TI of birds. Both experimental factors and their interaction significantly affected plasma creatine kinase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. Cholesterol and triglycerides were not different between the experimental groups, whereas glucose decreased after 4 hours of transport in both strains. A significant difference between groups for the heterophils/lymphocytes ratio after transport was also observed, with NN being higher than Ross. Concerning the oxidative stress, we observed a higher ROS production in NN chickens. The carcase microbial characteristics showed a higher level of contamination after the transport (total viable counts), but not concerning the Enterobacteriaceae counts.