[Construction of black-bone silky fowl (Gallus gallus domesticus) families based on genetic diversity].

Black-bone silky fowls(Gallus gallus domesticus) have a long history of medicinal use, with the origin in Taihe county, Jiangxi province. The unclear family composition, inbreeding rate, and effective population size were inconducive to the resource conservation or breed improvement of black-bone silky fowls. A genome-wide analysis was performed to evaluate the genetic diversity of 80 black-bone silky fowls from random mating in three farms in 2021 in terms of minor allele frequency(MAF), expected heterozygosity(H_e), observed heterozygosity(H_o), effective population size(N_e), and runs of homozygosity(ROH). The results showed that a total of 9 641 411 SNPs were passed quality control from 80 black-bone silky fowls. The polymorphic marker ratio, expected heterozygosity, and observed heterozygosity in this population were 0.81, 0.34, and 0.33, respectively, and the average IBS genetic distance of black-bone silky fowls was 0.38±0.008 2. A total of 15 969 ROHs were identified, with the average length of 0.73 Mb, and most of the ROHs were 0～2 Mb. According to inbreeding ROHs, the average inbreeding coefficient was 0.150 9. The high-frequency ROH regions harbored 424 genes, including two genes, SLC13A4 and DDX6, associated with pigmentation. The results showed that the genetic relationship between individuals of black-bone silky fowls was far. The population had experienced a strong decline in size in recent decades, and the inbreeding degree was high. According to the results, an appropriate family construction scheme was proposed for resource conservation and breeding work of black-bone silky fowls.