Local Ancestry and Adaptive Introgression in Xiangnan Cattle

Exploring the genetic landscape of native cattle is an exciting avenue for elucidating nuanced patterns of genetic variation and adaptive dynamics. Xiangnan cattle, a native Chinese cattle breed mainly produced in Hunan Province, are well adapted to the high temperature and humidity of the local environment and exhibit strong disease resistance. Herein, we employed whole-genome sequences of 16 Xiangnan cattle complemented by published genome data from 81 cattle. Our findings revealed that Xiangnan cattle are pure East Asian indicine cattle with high genetic diversity and low inbreeding. By annotating the selection signals obtained by the CLR, <i>θ</i>π, <i>F</i>_ST, and XP-EHH methods, genes associated with immunity (<i>ITGB3</i>, <i>CD55</i>, <i>OTUD1</i>, and <i>PRLH</i>) and heat tolerance (<i>COX4I2</i>, <i>DNAJC18</i>, <i>DNAJC1</i>, <i>EIF2AK4</i>, and <i>ASIC2</i>) were identified. In addition, the considerable introgression from banteng and gaur also contributed to the rapid adaptation of Xiangnan cattle to the environment of Southern China. These results will provide a basis for the further conservation and exploitation of Xiangnan cattle genetic resources.