The aim of the study was to define poultry adaptability to organic system, through the assessment of several endpoints. Eight hundred male birds of slow-growing birds (Ancona: A, Leghorn: L, crossbreed Cornish  Leghorn: CL), medium-growing (Gaina: G, Robusta Maculata: RM, Kabir: K, Naked Neck: NN) and fast-growing strains (Ross: R) were organically reared. A and L genotypes displayed a quicker reaction time when submitted to tonic immobility test, and a great variety of behaviour and exploiting all the pasture area. Concerning feather conditions L, A, CL G and RM showed the best values for all considered body regions, as well as the absolute absence of foot pad and breast blister lesions. Static behaviour of R and G chickens did not produce a significant oxidative burst whereas, the active behaviour of A, slow-growing birds, increased the oxygen demand. Plasma a-tocopherol followed the trend of kinetic and foraging activity being higher in slow-, intermediate in medium-and lower in fast-growing birds. The adaptability index showed the best result of slow-growing strains with intermediate results in medium-growing and the worst in fast-growing ones. There is a negative linear correlation between adaptation and daily weight gain. However, within the same sub-group (slow, medium and fast), there is no correlation between daily weight gain and adaptation to an organic system. Even if R chickens had the highest productive performance, they appeared no adapted to the organic system. Daily weight gain (<50 g/d) is a prerequisite for chicken adaptation, but even birds with similar weight gains showed wide variations in the adaptation. ARTICLE HISTORY
In alterative rearing systems, the use of outdoor space has a crucial role. It is well known that only some commercial poultry genotypes are suitable to be reared in these systems. It is necessary to find a balance between productive performance and adaptability. The aim of this study was to evaluate the productive performance, behavior, and welfare status of six poultry genotypes reared in an organic system. One hundred males/genotype (Hubbard RedJA (A), CY5XJA87 (CY), M22XJA87 (M), Ranger Classic (R1), Ranger Gold (R2), and Rowan Ranger (R3)) were reared from 1 to 81 days of age. The number of culled birds was recorded daily, whereas live weight and feed consumption were recorded weekly. Behavior evaluation was undertaken through a computerized system one week before slaughtering; the breast yield and muscle/bone ratio of the drumstick was also evaluated in refrigerated carcasses. The results showed that A and R3 had good adaptability, showing active behaviors and satisfactory productive performance 3083.6 g and 3022.1 g, respectively. Although CY and M achieved the best productive performance, they did not appear adapted to the organic system due to a higher frequency of static behaviors (rest and roost), mortality, footpad dermatitis, breast blisters, and poor feather condition.
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.
The aim of this study was to analyze the relationship between the kinetic behavior, carcass characteristics, oxidative status (blood and meat), and meat fatty acid profiles of 6 organically reared slower growing chicken genotypes ( SrG ). One hundred male chickens of 6 SrG were used: Ranger Classic ( RC ), Ranger Gold ( RG ), Rowan Ranger ( RR ), RedJA ( RJ ), CY Gen 5 JA87 ( CY ), and M22 × JA87 ( M ). Twenty chickens/genotype were selected to analyze behavior, while, 15 individuals were slaughtered and different traits were analyzed in the blood and drumstick meat. The variables were grouped into different principal components: kinetic activity (PC1, with explorative attitude as the highest score), productive performance (PC2, carcass and head/feet yields), blood (PC3, carbonyls, and TBARS) and meat (PC6, thiols, and TBARS) markers, technological traits (PC4, pH, and color), proximate meat composition (PCA5, moisture, lipids, protein, and ash), fatty acid profile, and nutritional indexes (PC7, IP, and PUFAn-3). Uni- and bivariate analyses showed a strong positive association between kinetic behaviors and blood and meat oxidation and a medium positive association with fatty acid profile and nutritional indexes, whereas a negative association was found between productive performance loads and the technological traits of meat. Generalized linear models showed that all PCs were influenced by genotype. In particular, CY and M resulted as less active genotypes; conversely, RR showed more kinetic activity, whereas RJ, RG, and RC exhibited intermediate levels of activity. Cluster analysis of kinetic behavior and blood or meat oxidative status highlighted 2 groups: nonwalking (NW: CY and M) and walking (W: RC, RG, RR, and RJ) animals. However, in the W group, another was visualized, constituted by genotypes with high kinetic activity resulting in the worst oxidative balance (Walking not trained-genotypes, Wnt: RR and RJ). The present results confirmed that the kinetic behavior of SrG genotypes is negatively correlated with productive performance. Furthermore, a significant association between kinetic behavior and blood (positively correlated) or meat (negatively correlated) oxidative status was noted. Such differences are mainly due to the intrinsic response of the genotypes used (i.e., training-walking capacity).
(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
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