Occurrence of naked neck and frizzle indigenous chicken genotypes and performance of their crosses with kuroiler

Abstract

The aim of this study was to determine the occurrence of Frizzle and Naked Neck genotypes in indigenous chicken populations and the performance of their crosses with Kuroiler. A questionnaire was administered to 121 farming households that were purposively selected. Information about the demographic characteristics, flock structure, perceptions about the Frizzle and Naked Neck genotypes and factors affecting their willingness to rear those chickens was collected and analysed using both descriptive statistics and binary logistic regression. The genotypic frequency of each genotype was determined using the Hardy Weinberg principle. To evaluate the performance of crosses, Kuroiler cocks were mated with Naked Neck, Frizzle and normal feathered females (control) to produce Kuroiler x Naked Neck (KuNa), Kuroiler x Frizzle (KuFr) and Kuroiler x Normal feathered (KuNo) crosses. Similarly, mating within each of the indigenous genotypes generated progeny that were used as controls. The resultant chicks were managed under an intensive system until the on-set of lay and egg production monitored for a period of 15 days. Growth characteristics (body weight gain), feed intake, feed utilization efficiency (FCR), egg production efficiency were determined for the different genotypes. Growth data were subjected to Gompertz and Logistic models to estimate mature weight growth rate and age at maximum growth rate of the different genotypes. Growth performance and egg production data were subjected to analysis of variance. Results from the survey showed that the proportion of Frizzled (5.5%) and Naked Necks (14.4%) were much lower than Normal feathered chicken (94.4%) in the indigenous chicken population. The calculated gene frequencies were 0.94, 0.0009 and 0.0591 for Normal feathers (NoNo), homozygous Frizzle (FrFr) and heterozygous Frizzle (Frfr) respectively and 0.86, 0.0049 and 0.1351 for Normal neck (nana), homozygous (NaNa) and heterozygous (Nana) Naked Neck genotypes respectively. Although majority of farmers (79.8%) expressed willingness to rear Frizzle chicken, only 38.8% had ever reared them and of the 85.5% that expressed willingness to rear Naked Neck, 67.8% had ever reared them. Rarity and difficulty to multiply, association with use in cultural traditions such as witchcraft, being male and limited demand were reported to negatively affect raring and perhaps abundance of Naked Neck and Frizzle genotypes. In addition, lack of total dominance of the frizzled and Naked Neck genes, low fertility of the eggs, low hatchability of eggs and high chick mortality was observed in during the study. Crosses of Kuroiler with all indigenous chickens genotypes performed significantly (p<0.05) better than the indigenous chickens in terms of weight gain, feed conversion and in all egg production efficiency parameters, but crosses with Naked Neck genes were superior in growth (p<0.05) while those with Frizzle genes were superior in egg production (p<0.05). For all parameters measured, including age at first egg, Normal feathered chickens, weather indigenous or crossed with Kuroiler, performed the least (p<0.05). The Gompertz model provided more realistic growth parameter estimates compared to the logistic model. This study provides evidence that Frizzle and Naked Neck genotypes populations are very low among the indigenous chicken population in the study areas and their low prevalence is attributed to their rarity, gender preference, use in cultural traditions , and low survivability as well as lack of dominance of these genes over normal feathered chickens. Kuroiler can be used to further improve the growth and egg production of Frizzle feathered and Naked Neck indigenous chicken genotypes. Because majority of the farmers are willing to rear both Frizzle and Naked Neck chickens and performance of crosses, it is recommended that sensitization of farmers, focusing on social-cultural negative perceptions and promoting positive attributes as well as conservation and breeding programs that utilize Kuroiler should be promoted.