Effect of Dietary Estradiol 17 on Growth, Hematology and Biochemistry of Stellate Sturgeon Acipenser stellatus

The effects of oral administration of different doses of estradiol-17 (E2) were examined on the growth performance, body composition, sex steroids, blood indices and histology of liver and gonad in Acipenser stellatus juveniles. Five-months-old fish (40.9 ± 1.1 g) were fed 0, 25 and 50 mg E2 kg diet for 210 1 days. Results showed that increasing doses of E2 caused reduce growth rate. No significant difference in condition factor (CF) was observed. Growth parameters such as final weight gain, specific growth rate (SGR), feed conversion ratio (FCR) and voluntary feed intake (VFI) had significant differences among treatments. Although the highest survival rate was observed in fish fed with control diet but without significant differences (P>0.05) among the treatments. With increasing dietary E2 levels, a decrease trend was observed in blood serum testosterone (T) and progesterone (P) levels. Also a negative pattern was obtained in plasma E2 level. Results revealed that white blood cells (WBCs) and red blood cells (RBCs) were reduced when E2 levels was increased in the diet. Body composition did not change in all treatments. The results showed that nutritional doses of E2 cause suppression of growth in A. stellatus juveniles.