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Newcastle disease and heat stress reduce the productivity of local chickens of Nigeria (LCN). This study compared the antibody response to Newcastle disease and heat tolerance among different LCN genotypes in hot humid tropics using multivariate discriminant analysis. A total of 299 birds were used for the study. Geometric mean titre against Newcastle disease before vaccination (GMTB), geometric mean titre against Newcastle disease after vaccination (GMTA), rectal temperature at week 4 (RT4), pulse rate at week 4 (PR4), respiratory rate at week 4 (RR4), heat stress index at week 4 (H4), rectal temperature at week 13 (RT13), pulse rate at week 13 (PR13), respiratory rate at week 13 (RR13) and heat stress index at week 13 (H13) were measured. All the traits were significantly (p

Coat colour contributes to physiological adaptation in mammals and mediates response to thermal stress. Twenty-four adult West African Dwarf sheep of both sexes and with different coat colour types were used in this study. We measured rectal temperature (RT), respiratory rate (RR) and pulse rate (PR) before sunrise and sunset during the late dry season (January–March) and early rainy season (April–June) as well as packed cell volume (PCV), red blood cell (RBC) count, white blood cell (WBC) count, plasma sodium (Na+) and potassium (K+). Animals with black coat colour had the highest (P

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.

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

Six-hundred-and-seven-day-old chicks were generated from Nigerian local chickens consisting of three genotypes (Normal-feathered; Frizzled-feathered; Naked neck) and an exotic broiler breeder (Anak Titan) to evaluate growth performance for possible meat-type chicken development. Growth parameters measured were body weight, breast girth and keel length on weekly basis for 20 weeks. Effects of sire, dam and chick genotypes were significant (P0.001) on growth traits. At week 20, chickens sired by the Anak Titan weighed 1,614.82 g followed by Normal-feathered local chickens with body weight of 1,211.32 g. Progenies of Anak Titan and Naked neck dams weighed 1,761.96 and 1,292.80 g at week 20, respectively. Among purebreds, Anak Titan weighed 35.05 g at day-old and had heaviest body weight of 2,360.29 g at 20 weeks compared to the three local strains. The average body weights for the crossbred, Normal-feathered × Anak Titan at day-old and week 20 were 36.39 and 1,577.63 g, respectively. This was followed by Anak Titan × Naked neck with 33.32 g at day-old and 1,514.14 g at week 20. Sex had significant effect (P0.05) at weeks 16 and 20 with the males having higher mean values than their female counterparts. This study revealed that crosses involving Anak Titan sire × Naked neck dam had highest growth performance, and there was no strain differences among the growth performance of purebred Nigerian local chickens.

The characterisation of the small ruminant populations in developing countries will play a major role in the maintenance of the genetic resources as the basis for future improvement in livestock production. The present study aimed at morphological characterisation of the two main breeds of sheep in Ghana by assessing variation within and between breed populations using principal component and discriminant analyses. The two breeds were the Sahel and the Djallonke sheep of both sexes and of two groups namely, young (1 year old, consisting of 74 animals) and mature sheep (≥ 2 years old, comprising 219 animals). The analysis of variance revealed significant (P0.05) differences in the morphological traits of the Sahel and the Djallonke sheep breeds with higher values recorded for the former. Sexual dimorphism was in favour of male animals in all the morphological traits examined. Mature animals also had comparative advantage over the young. Two principal components were extracted to discern the structure of the two genetic groups. The most discriminating traits between the two sheep breeds were rump height, height at withers, neck girth and pin-bone width. Mahalanobis distance between the two genetic groups was 5.723 (P0.0001). The developed discriminant functions clearly discriminated and classified the Sahel and the Djallonke sheep into their breeds of origin, thus yielding 100, 93.4 and 90.4 % accurate classification for the rams, ewes and the overall sheep population, respectively. The present approach would greatly help in establishing management and conservation policies for the sustainable production of the two Ghanaian sheep breeds.