الفهرس 
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Abstract
35mature, ripe female Clariaslazera with mean weight of 0.6 ± 0.1kg were divided into 7 equal groups (5 fish each) and injected by GnRHa and HCG with dopamine antagonists (domperidone and metoclopramide),lag period, ovulation rate, egg mass weight, fecundity and hatchability %were recorded. Blood samples were taken after stripping and serum were aspirated and determined by Enzyme Immunoassay. The results showed that, using GnRHa or hCG together with dopamine antagonists were more effective in induction of ovulation, increasing egg mass, fecundity and hatchability% compared with the other spawning stimulators used in the study. The highest ovulation rate (100%) was observed in G3, G4, G6 and G7 followed by (80%) in G2 and G5andthe lowest lag period (10hrs) was in G4 while the longest lag period (14hrs) was in G5.The total egg mass weight showed significant difference with the lowest value (58g) in G5 and the highest value (82g) in G4. Fish of G4 showed the highest value of fecundity while G5 was the lowest value. Hatchability% showed significant differences where the highest% was observed in G4 (54.80%) and the lowest% was in G5 (40.18%). A significant decrease was observed in serum levels of estradiol-17β and cortisol after stripping compared with control group. The results recommended using dopamine antagonists with GnRHa or HCG for increasing fry production in Clarias lazera.