The occupied proportion of hair follicle group in Inner Mongolia cashmere goat (Capra hircus)

Abstract

Despite the significant advantages of using indigenous Chinese goat breeds in cashmere production, yield improvement is an ongoing challenge to cashmere goat breeding. This study aimed to investigate the occupied proportion of hair follicle group (HFG) and examine its influence on total hair follicle density (THFD). A total of 459 skin samples from the Inner Mongolia cashmere goat were processed for paraffin embedment, transverse sectioning, and H&E staining. An image of 9.26 mm2 was captured for each sample. All hair follicles were marked as color dots and the areas occupied by HFGs were filled by color blocks. Color blocks and the corresponding color dots were then analysed to calculate parameters. Our results showed that those samples with the higher THFD had the following characteristics: the size of the HFG (Size-HFG) was smaller, the HFGs (Num-HFG) was denser, the area proportion of the HFGs (Ratio-HFG) was larger, and the hair follicle density within HFG (Int-THFD) was higher. For each sample, its THFD was directly determined by the Int-THFD and Ratio-HFG. By improving one or both of Int-THFD and Ratio-HFG, a higher THFD can be achieved, thereby increasing the cashmere yield. This work implied that the Inner Mongolia cashmere goat still has upward potential for THFD improvement.