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Abstract
The mammalian body is composed of highly differentaiated structures that function as one unit the vital processes are controlled by two systems namely the nervous system and the endocrine system these two systems are also serve to change the activity of the organism in response to changes in the external environment Steinberg and russel and Clermont 1977 stated that the developmet of the male gonads of the mammalian species which are controlled by the endocrine organs and through the control of the hypothalamus of the brain are synchronized with the external factors therefore youngs should be cared under favourable conditions.