blood sample
Sheep blood DNA was extracted using a CWE9600 Magbead Blood DNA Kit (Beijing Kangwei Century Biotechnology Co., Ltd., Beijing, China). The concentration of DNA was accurately measured using a Qubit fluorometer, and the purity of DNA samples was detected using a NanoDrop micro-spectrophotometer (the accepted value to include the sample in the analyses was OD260/OD280 = 1.72.1). Subsequently, 0.8% DNA agarose gel electrophoresis was performed to determine the degree of DNA degradation. After assessing DNA quality, gene libraries were assembled, with an average fragment size of 300 bp per sample. Sequencing was performed using a DNBSEQ-T7 sequencer.