Comparative study on hormones and biochemistry indices in plasma,ovarian fluid and oocytes of LHRHa2‐induced female Stellate sturgeon (Acipenser stellatus)

Reproduction efficacy of sturgeon as donors of oocytes is regulated by hormones effects. It can influence the egg quality or larvae functions as rearing mediators for successful production. This study is conducted to evaluate the concentration of sex steroids, cortisol and thyroid hormones and distinguish the relationship of maternal hormones' correlation in Stellate sturgeon. The study followed the hormones fluctuations that could impress some egg quality information such as fertilization rate. Female breeders were injected with LHRH_a2 for controlled propagation. Samples from blood, ovarian fluid and oocytes were obtained for hormonal and biochemical analysis. Our results showed that the concentrations of estradiol 17‐β and testosterone were significantly higher and lower in oocyte and the plasma, respectively. The level of plasma cortisol was significantly higher than in ovarian fluid and oocytes. The results showed elevation of triiodothyronine and thyroxine concentrations in oocytes, which were significantly different with plasma and ovarian fluid. Thyroxine concentration of plasma and ovarian fluid revealed a significant negative correlation. The mentioned parameters showed negative correlation with fertilization rate. The biochemical parameters (calcium, glucose, cholesterol and triglyceride) revealed significant differences in blood, ovarian fluid and oocytes. These results showed direct relations of fertilization rate with hormones level. Therefore, fertilization rate as egg quality index could be recommended as a relevant indicator of maternal transferring of hormones from blood and ovarian fluid to oocyte.     

The use of fenugreek seed meal in fish diets: growth performance,haematological and biochemical parameters,survival and stress resistance of common carp (Cyprinus carpio L.)

The present study was conducted to investigate the effects of fenugreek seed meal (FKSM) on growth performance, blood haematological and biochemical factors, survival and stress resistance of the common carp (2.46 ± 0.06 g) fingerlings. Four practical diets containing 0 (control), 0.5%, 1% and 1.5% FKSM were used to feed fish. Fish were fed on the tested diets at a rate of 3% of body weight for 8 weeks. Results indicated that fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). Feed conversion ratio decreased significantly in fish fed diets containing FKSM. There were no significant differences in glucose levels, red blood cell count, haematocrit and haemoglobin between treatment groups and the control group (P > 0.05). Significantly lower white blood cells count was observed in fish treatment with FKSM when compared with the control group (P < 0.05). The cholesterol level in group fed supplemented diet by 1% fenugreek significantly lower than other groups (P < 0.05). Total protein levels were significantly higher in all treatments compared to the control (P < 0.05). No mortality was recorded during the feeding trial. In salinity stress experiment, highest survival rate belong to fish fed supplemented diet by 1% fenugreek. These results indicate that FKSM can be considered as a beneficial dietary supplement for improving the growth performance and blood indices of common carp fingerling.