Evaluation of ranging ability and production traits of various genotypes of chickens (Gallus gallus domesticus Linn.) under organic management system

The study was conducted to evaluate the ranging ability and productive traits of various genotypes of chickens under organic management system. It was comprised of four experiments. The first experiment dealt on development of the methodology and evaluation of ranging ability of various genotypes of chickens. Also, in the first experiment, the influence of agroecosystem on the expression of ranging ability was determined. In the second experiment, the ranging ability of various genotypes of chickens was evaluated in relation to productive traits and slaughter yield data. The third experiment was done to evaluate the genotypes - Banaba (BB), Paraoakan (PP), Sasso (SS), Banaba x Sasso (BS) and Paraoakan x Sasso (PS), in terms of productive traits, physicochemical properties, and organoleptic attributes of the meat. The fourth experiment was conducted to determine the correlation of ranging ability to the productive traits under organic management system. The first experiment showed that ranging ability varied from one genotype to another. The strains of Philippine native chickens (BB and PP) and the crosses (BS and PS) had significantly (P.05) higher ranging score (by 30-60%) as compared to Sasso chickens (SS). These implied better adaptability of BB and PP to five-ranging conditions under organic management system. The ranging ability of the crosses (BS and PS) was at par with the Philippine native chickens (BB and PP). Also, in the first experiment, it was observed that the ranging ability varied from one agroecosystem to another. The ranging score was significantly higher (P.05) in rambutan orchard with 52 m/hr followed by the ranging score in grassland with 48 m hr. The ranging score was lowest in rice-based agroecosystem. Such differences were attributed to the different bio-physical conditions. In the second experiment, it was found that Banaba (BB) and the cross between Banaba x Sasso (BS) had significantly higher ranging score as compared to Sasso (SS) and Manila Bird (MM). However, in terms of body weight, feed conversion and cost of producing a kg of meat, MM and SS performed better as compared to BB and BS. In the third experiment, it was observed that crude fat was significantly (P.05) higher in SS (5.6%) compared to BB and PP with 1.5 and 3.5%, respectively. The crosses had crude fat content in between values of the parents. The genotypes with higher ranging score were the same genotypes with lower crude fat content in the meat. In terms of censory properties, the scores on flavor were significantly higher in BB and PP as compared to SS. The crosses had intermediate scores on flavor. The ranging score was found to be negatively correlated with body weight (P.05). The correlation coefficient (r) was highest in PP with values ranging from -0.40 to -0.60. Also significant correlations were obtained from ranging score with body dimensions (wing span and shank circumference) and cut-up parts (drumstick and head), whether expresses as actual weights or based on a per unit body weight.