<div>Background: Bird is important in maintaining biodiversity and its lifestyles and behaviors will pose an important impact on the ecological environment. Birds are also inseparable for ecological stability. Birds&rsquo; movement and living habits are a widely studied topic. 
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Methods: Two economic valuable birds, Lonchura striata and Copsychus saularis, were selected in this study. It aims at investigating the characteristics of muscle fiber tissues and comparing the differences between male and female species. Histological techniques were used to determine the characteristics of the muscle fiber (diameter, area and density) in leg and pectoral muscles. 
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Result: There were differences in the muscle fiber characteristics of the Lonchura striata and the Copsychus saularis. The characteristics of muscle fibers between males and females of the same species were significantly different and there were also significant differences in the same parts of different species. The diameter and area of muscle fibers are correlated to the density of muscle fibers. This study suggested that the characteristics of muscle fibers are related to their living habits and population characteristics.</div>

Comparison of the Structure of Leg and Pectoral Muscles between Lonchura striata and Copsychus saularis