Effect of LHRH-A2 on stress indices of cultured sterlet sturgeon (Acipenser ruthenus)

Hormonal injection as the final maturation effective tool, cause some effects onovulation and stress indices which led to physiological changes and final maturationof gametes. In this study, 18 sterlet females with an average weight of 1132.4 ± 248.5g in three treatments were considered and injected with 10 μg/kg LHRH-A2intramuscularly in two stages with 10 and 90 percent as priming and resolving doses,respectively. Blood samples were collected in three different stages; before injection(control), 12 hours after the first injection and after ovulation. Plasma levels ofcortisol, glucose and lactate were measured by radioimmunoassay and colorimetricmethods, respectively. After hormone injection, significant differences wereobserved in glucose levels (P<0.05), which the maximum (69.8 ± 5.9 mg/dl) andminimum (45.3 ± 1.4 mg/dl) levels were observed in the first injection and ovulation,respectively. Meanwhile, cortisol and lactate were not significantly different(P> 0.05). Based on the obtained results, this study revealed some secondaryresponses to LHRH-A2 injection in ovulation.

Keywords:

LHRH-A2 , CORTISOL , Glucose , Lactate , Sturgeon