Characterisation of Saudi native chicken breeds: a case study of morphological and productive traits

Genotypic and phenotypic characterisation of three local chicken ecotypes of Ghana based on principal component analysis and body measurements

This study aimed to characterise three Ghanaian local chicken ecotypes, namely, Interior Savannah, Forest, and Coastal Savannah, based on morphological data and single nucleotide polymorphism (SNP) genotypes. Morphological data including body weight, shank length, body girth, back length, thigh length, beak length, comb length, and wattle length were collected from 250 local chickens. DNA isolated from blood of 1,440 local chickens was used for SNP genotyping with the Affymetrix chicken 600k SNP chip. Principal component analysis showed that Forest and Coastal Savannah birds were closely related. Generally, all three ecotypes exhibited high genetic diversity, especially birds from the Interior Savannah zone. Morphological characterisation showed that ecotype (p = 0.016) and sex (p = 0.000) had significant effects on body weight. Birds of the Interior Savannah ecotype were the heaviest (p = 0.004), with mean weights of 1.23 kg for females and 1.40 kg for males. Sex also had a strong significant effect on most of the morphological measurements, but the sex * ecotype interaction effect was not significant. Very few of the feather phenotypes previously reported to be associated with heat resistance-frizzle (2%) and naked neck (1.6%)-were found in the studied populations. It is concluded that the three local ecotypes are genetically diverse but with similar morphological features and the information provided would be useful for future selection decisions.

Indigenous chicken production system in different agro-ecology of Indian Himalayan Region: implication on food and economic security

The indigenous chicken production system (ICPS) has several use values and ecosystem services. In the last few years, ICPS has been recognized for its possible contribution to household food security, income generation, wildlife protection, and bettering the women's lives. This study aimed to collect, for the first time, comprehensive information about ICPS in three different agro-ecologies (tropical, sub-tropical, and sub-temperate) of the Indian Himalayan Region (IHR) and its role in food and economic security of traditional communities. In this study region, ICPS is semi-extensive, providing homegrown feed and temporary night shelter. In sub-temperate agro-ecology, females owned non-significant (p = 0.170) more indigenous chicken flocks than males. Households in sub-temperate agro-ecologies had significantly (p ≤ 0.001) larger flock sizes and tropical livestock units (chicken-TLU). However, the livestock diversity index (LDI) was significantly higher (p ≤ 0.001) in tropical and subtropical agro-ecology. The households in the sub-temperate region highly (p ≤ 0.001) valued indigenous chicken because of its survivability and adaptability. In absolute numbers significant (p ≤ 0.001) higher numbers of adult birds died in past 1 year in sub-temperate agro-ecology. The mortality rate of adult birds in sub-temperate agro-ecology was 9%, and it was 14 and 15% in tropical and sub-tropical agro-ecologies, respectively. In sub-temperate agro-ecology, larger flock size translated into significantly higher (p ≤ 0.001) egg production and subsequently a significant (p ≤ 0.001) higher egg consumption per household per month. In sub-temperate agro-ecology, households' dietary diversity score was significantly (p ≤ 0.001) higher. Similarly, the average annual income from ICPS was significantly higher (p ≤ 0.001) in sub-temperate agro-ecology and accounted for 18% of household income. ICPS' marketing chain was relatively short in the sub-temperate region. In all agro-ecologies, indigenous chicken and egg demand was significantly higher (p ≤ 0.001) in the winter. ICPS litter is used as farmyard manure, enhancing ecological resilience. In all agro-ecologies, the three most frequently cited obstacles to extending the indigenous chicken production system are illnesses, predators, and a lack of chicks availability. ICPS contributes to food and nutritional security, economic stability, and ecological resilience in this hilly and fragile ecosystem. Even though the system is self-sustaining, management and health interventions can increase production and productivity.

Genetic diversity and population structure of indigenous guinea fowl (Numida meleagris) in Benin using simple sequence repeat markers

This study aimed to assess the genetic diversity and population structure of 12 guinea fowl phenotypes from three climatic zones (Guinean, Sudano-Guinean and Sudanian) of Benin. A total of 96 adult guinea fowl, aged at least 6 months, were selected for blood sampling. Fragment analysis was carried out using 17 polymorphic microsatellite markers. The informative marker combinations revealed a total of 83 alleles across all loci, with an average of 5 alleles per locus and a mean polymorphic information content (PIC) of 0.793. This study showed an observed heterozygosity of 0.492. The inbreeding coefficient values ranged from - 0.086 in white phenotype to 0.226 in cinnamon, showing a deficit of heterozygotes, suggesting a moderate inbreeding level. A relatively low population differentiation was observed, with a mean fixation index (Fst) value of 0.033. The short genetic distances between phenotypes, unlike the strong genetic identities, revealed high genetic proximity between the 12 phenotypes of indigenous guinea fowl in Benin. These data indicate the existence of a single indigenous guinea fowl population with high intra-population genetic diversity with respect to climatic zones or phenotypes. This study will help in the selection of parental breeding stock for genetic improvement programs, as well as in the conservation for biodiversity maintenance and sustainable use of the indigenous guinea fowl in the study zones in Benin.

Influence of Genotype on Productivity and Egg Quality of Three Hen Strains Included in a Biodiversity Program

The aim of the study was to evaluate the effect of genotype on the productivity and egg quality of three hen strains included in the genetic resource protection program in Poland. The study encompassed populations of laying hens, i.e., Rhode Island Red/RIR (R-11 and K-22) and Rhode Island White (A-33). The analysis over five generations included the basic production traits, i.e., the weight of the birds at 20 weeks (g), egg weights at 33 and 53 weeks, sexual maturity, the number of eggs laid up to 56 weeks of age, and hatchability parameters. In addition, the effective population size (Ne) and flock homozygosity coefficient (Fx) were calculated for each breed. Population health during the rearing and production periods was also recorded. The study also determined egg content and shell quality traits in relation to the age of the hens. The birds were kept on litter at a stocking rate of 5 hens/m2 and fed ad libitum with a standard feed mixture for hens. Based on the results, it was concluded that the evaluated hen populations (R-11, K-22, and A-33) are valuable strains, representing a reservoir of unique phenotypic and egg quality traits. It was shown that the random mating system used in the reproduction of flocks effectively protects the populations from an increase in the degree of inbreeding. An influence of hens' origin (genotype) and age on the performance results, as well as egg quality traits, was found. Over five generations, the evaluated hen strains were characterized by high survival rates (above 98%). The study also found a large variation between the R-11 and K-22 strains and the A-33 strain in terms of the evaluated performance traits, especially in the body and egg weights, sexual maturity age, and laying performance of hens. The earliest to start laying were hens from the K-22 strains, which also showed significantly (p ≤ 0.05) higher laying performances compared to R-11 hens. The results also indicate that the quality of eggs from hens of the compared strains varied. This was particularly true for such traits as shell color; egg, shell, and yolk weight; and shell quality. It was also shown that many egg and shell quality traits change with the age of the hens. The analysis of the obtained data indicates that the adopted methods of conservative breeding for these populations have influenced the success of the conservation program.

Genetic diversity and population genetic structure of Cambodian indigenous chickens

Objective

Cambodia is located within the distribution range of the red junglefowl, the common ancestor of domestic chickens. Although a variety of indigenous chickens have been reared in Cambodia since ancient times, their genetic characteristics have yet to be sufficiently defined. Here, we conducted a large-scale population genetic study to investigate the genetic diversity and population genetic structure of Cambodian indigenous chickens and their phylogenetic relationships with other chicken breeds and native chickens worldwide.

Methods

A Bayesian phylogenetic tree was constructed based on 625 mitochondrial DNA D-loop sequences, and Bayesian clustering analysis was performed for 666 individuals with 23 microsatellite markers, using samples collected from 28 indigenous chicken populations in 24 provinces and three commercial chicken breeds.

Results

A total of 92 haplotypes of mitochondrial D-loop sequences belonging to haplogroups A to F and J were detected in Cambodian chickens; in the indigenous chickens, haplogroup D (44.4%) was the most common, and haplogroups A (21.0%) and B (13.2%) were also dominant. However, haplogroup J, which is rare in domestic chickens but abundant in Thai red junglefowl, was found at a high frequency (14.5%), whereas the frequency of haplogroup E was considerably lower (4.6%). Population genetic structure analysis based on microsatellite markers revealed the presence of three major genetic clusters in Cambodian indigenous chickens. Their genetic diversity was relatively high, which was similar to findings reported for indigenous chickens from other Southeast Asian countries.

Conclusion

Cambodian indigenous chickens are characterized by mitochondrial D-loop haplotypes that are common to indigenous chickens throughout Southeast Asia, and may retain many of the haplotypes that originated from wild ancestral populations. These chickens exhibit high population genetic diversity, and the geographical distribution of three major clusters may be attributed to inter-regional trade and poultry transportation routes within Cambodia or international movement between Cambodia and other countries.

Temporal Trends in Performance and Hatchability Traits of Eight Strains of Hens Covered by the Gene Pool Protection Programme in Poland

The aim of the study was to determine trends in performance and hatchability traits of eight strains of hens that have been covered by the gene pool protection programme in Poland over ten years/generations. The study involved conservation populations of laying hens: Greenleg Partridge (Z-11), Yellowleg Partridge (Ż-33), Sussex (S-66), Leghorn (H-22, G99), Rhode Island Red (R-11, K-22) and Rhode Island White (A-33), which were maintained at the Experimental Station of the National Research Institute of Animal Production in Chorzelów. The following productive traits were analysed for each population: body weight at 20 wk (g), egg weight at 33 and 53 wk, sexual maturity and number of eggs laid per hen up to 56 wk of age. Mortality and culling were also recorded during rearing and production periods. Furthermore, effective population size (Ne) and inbreeding coefficient in the population (Fx) were calculated for each strain. The analysis of the performance results of the eight strains of hens and their trends indicate that the methods of conservation breeding adopted for these populations enable effective implementation of the conservation programme. The strains were found to differ in all the performance traits subjected to evaluation. Over the 10 generations, the strains examined showed high survival and hatchability parameters during both rearing and production periods. The currently used random mating system proved effective to prevent the populations from an increase of inbreeding. However, a worrying downward trend in body weight was observed in some strains.