Comparative analysis of muscle fiber characteristics of skeletal muscle between Yili horsess and Kazakh horsess

Hu Qingsong; Cai Yongbin; Ju Ao; Liu Xiaojie; Tian Manlin; Yibibaimu Reyixian; Ruan Fei; Meng Jun

doi:10.20154/j.cnki.issn1672-9692.2025.05.013

Abstract：To explore the characteristics of muscle fibers in the same part of the main skeletal muscles of Yili horses and Kazakh horses,and to provide references at the muscle fiber level for the breeding of Yili horses and Kazakh horses.Six Kazakh horses and six Yili male horses were selected for the experiment.After slaughter,the triceps brachii,longus dorsi,external oblique abdominal muscle and biceps femoris were taken respectively for immunohistochemical staining.The slice results were analyzed using Image-J software to obtain the number of muscle fibers,the average area of muscle fibers and the proportion of muscle fiber area.The results showed that the number of fast muscle fibers of the longest dorsal muscle in Yili horses was extremely greater than that in Kazakh horses(P<0.01),and the number of fast muscle fibers of the external oblique muscle was extremely less than that in Kazakh horses(P<0.01).The number of slow muscle fibers in the dorsal longus muscle was extremely smaller than that in Kazakh horses(P<0.01),and the number of slow muscle fibers in the biceps femoris muscle was extremely larger than that in Kazakh horses(P<0.01).The average area of the fast muscle fibers of the triceps arm in Yili horses was significantly larger than that in Kazakh horses(P<0.05),and the average surface area of the fast muscle fibers of the external oblique muscle was extremely larger than that in Kazakh horses(P<0.01).The average surface activity of the slow muscle fibers of the triceps brachii was extremely smaller than that of the Kazakh horse(P<0.01),and the average surface activity of the slow muscle fibers of the external oblique abdominal muscle was extremely larger than that of the Kazakh horse(P<0.01).The proportion of muscle fiber area of the triceps brachii and longus dorsi slow muscles in Yili horses was extremely smaller than that in Kazakh horses(P<0.01),the proportion of muscle fiber area of the external oblique abdominal slow muscles was extremely larger than that in Kazakh horses(P<0.01),and the proportion of muscle fiber area of the biceps femoris slow muscles was significantly larger than that in Kazakh horses(P<0.05).Studies show that the aerobic exercise potential of the triceps brachii and longus dorsi muscles of Yili horses is lower than that of Kazakh horses,while the aerobic exercise potential of the external oblique abdominal muscles and biceps femoris is higher than that of Kazakh horses.