Repeated administration of different hormonal preparations for artificial propagation and their effects on reproduction, survival and blood biochemistry profiles of female tench ( Tinca tinca L.)

The aim of the study was to compare physiological statuses of stripped and not stripped tench females with ovulation induced by GnRHa or carp pituitary extract (CPE). The comparison was based on selected biochemical stress indices (cortisol, glucose), condition (TP, TGA), and cell membrane characteristics (ALT, AST, CK). In the first and in the second year, 37 and 29 tench females were monitored, respectively. No differences in the values of biochemical parameters in either period were found between the two groups of stripped female tench whose ovulation was induced by GnRHa and CPE, respectively. No significant differences in TP, TGA, ALT, AST and CK values were found between the groups of stripped and not stripped females with ovulation induced by GnRHa or CPE. Different values were found in stress indices, specifically in glucose concentrations. A significant increase ( P < 0.01) in glucose concentrations was found in tench females immediately after stripping and, in not stripped females, about 48 hrs after ovulation induction. Both artificial stripping and the inability to release eggs are important stress factors for female tench.