الفهرس 
A biological analysisOnly 14 pages are availabe for public view
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Abstract
Food deficiency related to shortage of animal protein has been among the most dramatic worldwide problems addressed by national governments. This has been especially of concern in developing countries such as Egypt which are characterized by steady population increases and increased demand for protein. Thus the search for new domesticatable food resources and the development of exploitable natural protein resources is essential to the growth of these countries. Fish farming and open-water fisheries are amovg the most flexible of the world’s food resources in the ability to produce excellent sources of high-grade protein to be eaten directly by humans, as well as to produce high quality sources of protein and nitrogen for livestock feed and agricultural fertilizers. This study is carried out to elucidate some aspects of the reproductive biology and physiology of Diplodus vulgaris, including descriptions of their breeding characteristics, histological characteristics of their gonads and pituitary gland, and determination of levels of circulatory sex steroid hormones.