In organic broiler chicken production the European regulation suggests to use indigenous breeds with slow-growing profile, high liveability, resistance to diseases and adaptability to outdoor local conditions. However in practice mostly fast-growing chickens are utilised due to their higher efficiency although they were selected for indoor rearing. This study aimed to compare the foot pad and carcass lesions as well as the behavior and plumage conditions of one egg-type slow-growing (SG) genotype (Brown Classic Lohman) and two meat-type strains, medium- (MG) (Naked neck Kabir) and fast-growing (FG) (Cobb 700), reared under organic conditions. A total of 360 1-d-old male chicks, equally divided into 3 experimental groups, were reared at a density of 10 birds/m2 in 3 poultry houses with outdoor pens (10 m2/bird) and fed the same organic diets. One week before slaughter, birds were evaluated for kinetic activity, tonic immobility and plumage conditions. At slaughtering, food-pad dermatitis (FPD) of all birds of each group were assessed by assigning them to one of 3 different classes: 0 = no remark (no lesion), 1 = mild lesions, 2 = severe lesions. The FPD score was obtained applying the formula reported in the EU proposal COM (2005) 221 final. Qualitative traits of carcass, such as skin damage and incidence of breast blisters were recorded. FG birds, in respect to MG and SG, performed the lowest kinetic activity, the highest percentage of laying behavior (90 vs 34 and 3%, respectively) and showed the higher value of tonic immobility (176 vs 114 and 77 sec). This finding indicated a scarce adaptation of FG to organic housing system also confirmed by their bad plumage conditions: total plumage score (15 vs 21 and 23) in particular for breast (1 vs 3 and 4), vent (2 vs 3 and 4), wings (2 vs 3 and 4) and tail (2 vs 3 and 3); respectively in FG, MG and SG birds. The incidence of foot pad lesion was dramatically higher in FG in comparison with MG and SG (Class 0= 3 vs 93 and 99%; class 1= 29 vs 7 and 1%; class 2= 68 vs 0 and 0% respectively). The FPD score was 151 for FG birds and less than 1 for the other genotypes. The occurrence of breast blisters of FG birds resulted noticeably higher (66%) than both MG (2%) and SG (0%). This trial confirms that genotype has a great effect on behavior and welfare conditions of birds and that MG and SG chickens are more suitable for organic rearing system.
Meluzzi A., F. Sirri, C. Mugnai, A. Dal Bosco (2009). Effect of genotype on welfare conditions of broilers reared under organic conditions. s.l : wpsa.
Effect of genotype on welfare conditions of broilers reared under organic conditions
MELUZZI, ADELE;SIRRI, FEDERICO;
2009
Abstract
In organic broiler chicken production the European regulation suggests to use indigenous breeds with slow-growing profile, high liveability, resistance to diseases and adaptability to outdoor local conditions. However in practice mostly fast-growing chickens are utilised due to their higher efficiency although they were selected for indoor rearing. This study aimed to compare the foot pad and carcass lesions as well as the behavior and plumage conditions of one egg-type slow-growing (SG) genotype (Brown Classic Lohman) and two meat-type strains, medium- (MG) (Naked neck Kabir) and fast-growing (FG) (Cobb 700), reared under organic conditions. A total of 360 1-d-old male chicks, equally divided into 3 experimental groups, were reared at a density of 10 birds/m2 in 3 poultry houses with outdoor pens (10 m2/bird) and fed the same organic diets. One week before slaughter, birds were evaluated for kinetic activity, tonic immobility and plumage conditions. At slaughtering, food-pad dermatitis (FPD) of all birds of each group were assessed by assigning them to one of 3 different classes: 0 = no remark (no lesion), 1 = mild lesions, 2 = severe lesions. The FPD score was obtained applying the formula reported in the EU proposal COM (2005) 221 final. Qualitative traits of carcass, such as skin damage and incidence of breast blisters were recorded. FG birds, in respect to MG and SG, performed the lowest kinetic activity, the highest percentage of laying behavior (90 vs 34 and 3%, respectively) and showed the higher value of tonic immobility (176 vs 114 and 77 sec). This finding indicated a scarce adaptation of FG to organic housing system also confirmed by their bad plumage conditions: total plumage score (15 vs 21 and 23) in particular for breast (1 vs 3 and 4), vent (2 vs 3 and 4), wings (2 vs 3 and 4) and tail (2 vs 3 and 3); respectively in FG, MG and SG birds. The incidence of foot pad lesion was dramatically higher in FG in comparison with MG and SG (Class 0= 3 vs 93 and 99%; class 1= 29 vs 7 and 1%; class 2= 68 vs 0 and 0% respectively). The FPD score was 151 for FG birds and less than 1 for the other genotypes. The occurrence of breast blisters of FG birds resulted noticeably higher (66%) than both MG (2%) and SG (0%). This trial confirms that genotype has a great effect on behavior and welfare conditions of birds and that MG and SG chickens are more suitable for organic rearing system.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.