Genotype effect on distribution pattern of maternally derived antibody against Newcastle disease in Nigerian local chickens.

This study was conducted to evaluate the variation in antibody from Newcastle disease (ND) vaccinated breeder birds and their progenies. The chicks were evaluated for maternally derived antibody (MDA) against ND virus and also the MDA transfer rate for each genotype. The local parent stocks were Frizzle-feathered, Normal-feathered, and Naked neck while an exotic parent stock (Anak Titan) was used for the purpose of comparison. Sera samples were collected from chicks generated at day 3 post-hatch, and sera were also collected from the parent stocks. The sera samples were stored at -20 °C until analysed. Enzyme linked immuno-sorbent assay (ELISA) test was used for the detection and quantification of antibodies to ND in the parent stocks and the chicks using IDEXX Newcastle Disease ELISA test kit. The least squares means of antibody titers for parent stocks were 413.333 ± 68.853, 426.333 ± 121.949, 481.667 ± 145.454, and 1148.333 ± 532.843 for Frizzle-feathered, Normal-feathered, Naked Neck, and Anak Titan, and the calculated MDA transfer rate was 96.4, 93.8, 88.7, and 34.7 % for Frizzle-feathered, Normal-feathered, Naked neck, and Anak Titan, respectively. The mean antibody titers for chicks were 398.6 ± 43.871, 400.0 ± 53.952, 427.0 ± 89.353, and 398.8 ± 57.593 for Frizzle-feathered, Normal-feathered, Naked neck, and Anak Titan, respectively. The antibody titers from parent stocks were higher than those observed in chicks for all the genotypes. The values obtained in this study indicated that parent stocks with their progenies were below protective level. The local parent stocks had higher transfer rate when compared to their exotic counterpart. Hence, there is an indication from this finding that the local chickens had a better transfer rate in relation to Anak Titan which is an exotic breed. Therefore, there is the presence of genetic variability for antibody transfer in the Nigerian local chickens and can be incorporated in designing a breeding program for better adaptive potential.

Application of principal component and discriminant analyses to morpho-structural indices of indigenous and exotic chickens raised under intensive management system.

The objectives of this study were to investigate the relationships between body weight and morpho-structural indices to predict body weight from their orthogonal body shape characters using principal component analysis and to morphologically classify the chicken genotypes using multivariate discriminant analysis. Data used were from 273 randomly selected 12-weeks-old indigenous chickens of normal-feathered (NF), frizzle-feathered (FF), naked-neck (NN) and Anak Titan (AT) genotypes. Phenotypic correlation among body weight and most biometric traits ranged from 0.227-0.876, -0.7-0.901, 0.034-0.968 and -0.207-0.849 for NF, NN and AT chickens, respectively. Factor analysis with varimax rotation of interrelated traits revealed three principal components which accounted for 83.1%, 74.4%, 78.8% and 76.5% of the total variance in NF, FF, NN and AT chickens in the order listed. Breast girth, keel length, thigh length, shank length and wing length were found to be the most discriminating variables to separate the chicken genotypes. The longest distance (72.54) occurred between AT and NF genotypes while the shortest distance (4.27) was recorded for FF and NN genotypes. Classification results showed that 85.2% of AT genotype was correctly classified into their source population. However, 22.7% of NF was misclassified as NN, while 33.3% of NN was misclassified as NF chickens. These results suggest that there is high rate of gene flow between these two indigenous chicken genotypes. Information obtained from this study may be considered useful in breed improvement programmes for selection, characterization, conservation and better management of Nigerian indigenous chickens.

Effect of crossbreeding on fertility, hatchability and embryonic mortality of Nigerian local chickens.

A total of 970 eggs were collected from matings involving three genotypes of Nigerian local chickens (Normal-feathered, Frizzle-feathered and Naked neck) and one exotic broiler breeder strain (Anak Titan) to evaluate the effect of crossbreeding on fertility, hatchability and embryonic mortality. Mating was achieved through artificial insemination. Sire genotype significantly (P < 0.05) affected percent fertility and percent dead-in-shell. Naked neck sire genotype had the highest dead-in-shell (19.5%) with the least being 7.5% for Frizzle-feathered chickens. Frizzle-feathered sire genotype had the highest fertility (90.5%) and hatchability (91.4%). Dam genotype had a significant effect (P < 0.01) on fertility and hatchability, with Anak Titan dam having the highest fertility and hatchability of 88.2% and 94.6%, respectively. Fertility and hatchability were significantly (P < 0.05) influenced by the interactive effect of sire and dam genotypes with Frizzle-feathered × Anak Titan having 98.5% fertility and 96.8% hatchability. Both straight and reciprocal crosses involving Frizzle-feathered genotype and Anak Titan resulted in higher mean values for fertility and hatchability when compared to crosses involving the other two local chicken genotypes. This result suggests that the use of the Frizzle-feathered genotype appears to be more desirable in fertility and hatchability trials.