Genetic characterization and conservation priorities of chicken lines

Abstract

Molecular markers are a useful tool for evaluating genetic diversity of chicken genetic resources. Seven chicken lines derived from the Plymouth Rock breed were genotyped using 40 microsatellite markers to quantify genetic differentiation and assess conservation priorities for the lines. Genetic differentiation between pairs of the lines (pairwise FST) ranged from 0.201 to 0.422. A neighbor-joining tree of individuals, based on the proportion of shared alleles, formed clearly defined clusters corresponding to the origins of the lines. In Bayesian model-based clustering, most individuals were clearly assigned to single clusters according to line origin and showed no admixture. These results indicated that a substantial degree of genetic differentiation exists among the lines. To decide priorities for conservation, the contribution of each line to the genetic diversity was estimated. The result indicated that a loss of 4 of the 7 lines would lead to a loss from 1.14 to 3.44% of total genetic diversity. The most preferred line for conservation purposes was identified based on multilocus microsatellite analysis. Our results confirmed that characterization by means of molecular markers is helpful for establishing a plan for conservation of chicken genetic resources.

Genetic characterization and population structure of six brown layer pure lines using microsatellite markers

“…The observed heterozygosity value established for the six brown layer pure chicken lines (0.42) is lower than the value reported by Tadano et al [24] for brown layers; by Tadano et al [25] for five PR lines; by Granevitze et al [26] for 5 brown layer and one broiler lines; and by Muchadeyi et al [27] for broiler lines (0.460 to 0.744), but higher than the value reported by Tadano et al [25] for two PR lines; and by Muchadeyi et al [27] for brown and white layer pure lines (0.32 to 0.41).…”

“…On the contrary, these figures are higher than the number of alleles reported by Granevitze et al [26] for three brown layer lines (3.04 to 3.44), for four broiler chicken lines (3.74 to 4.79) and for one white layer line (2.96). They are also higher than the number of alleles per locus reported by Tadano et al [7] for RIR-A and RIR-B lines (4.25, 3.28, respectively); the number of alleles reported by Tadano et al [25] for seven PR lines (in the range of 2.70 to 4.20).…”

“…Tadano et al [24] reported that pairwise FST values on 5 closely related chicken lines produced from Nagoya (NG) chicken breed varied between 0.02 (NG4-NG5) and 0.25 (NG1-NG2), while Tadano et al [25] specified that the same value was in the range between 0.20 (PR2-PR3) and 0.42 (PR4-PR5) along the PR line. Five pure lines obtained from the Nagoya breed, i.e.…”

Gene conservation of six Hungarian local chicken breeds maintained in small populations over time

“…Although high-throughput SNP techniques have been more preferred for a while [9], microsatellite markers have similarly proven to be efficient molecular tools particularly in temporal studies [10] for assessing changes in genetic diversity as well as for setting priorities for conservation [11]; this has been especially applicable in the case of local chicken breeds [12][13][14][15][16][17][18]. Nevertheless, despite the high level of thoroughness and attention to detail in the investigations, any results obtained can easily become obsolete in the case of small populations where lifespans are more limited, and thus generations tend to change more frequently.…”

Insights into the genetic diversity of indigenous goats and their conservation priorities

“…Conservation priorities have been studied using the methods described above for domestic animals, including cattle [14], pig [10], sheep [15], chicken [16], horse [17], and goat. However, priorities for Chinese indigenous goat breeds have not been examined, except for one study in which the Weitzman approach was used to rank 12 mutton goat breeds [18].…”