Table 2. — Effects of carp pituitary on yellowtail flounder receiving daily injections. All fish were exposed to 11L:13D photoperiod and 

 water temperatures of 8.5°-12.5°C (Mean 10. TC). Symbols: + = did, = did not hydrate or ovulate. 



Dosage 



No. of Total Initial 



injec- length body weight Weight change GSI 



tions (mm) (g) (°o initial wt) (% final wt) 



Effect 



Hydrated Ovulated 



Date of 



spawning 



1976 



Ferti- 

 lization 



(%) 



Hatch 



(%) 



2.0 mg/kg fish 



Controls 



5.0 mg/kg fish 



Controls 



10 mg/kg fish 



Controls 



5 

 6 

 4 

 5 



10 

 5 



10 



5 

 4 

 5 

 5 



7 

 10 

 10 



348 

 340 



353 



435 



280 



350 



396 

 392 



421 



817 



263 



381 



+ 6.94 

 - 1 84 



-330 



-0.96 



-049 



1.12 



19,7 

 5.6 



5.1 



4.3 



7,0 



8.4 



+ 

 + 

 

 



+" 



+ 2 





 

 



+ 

 + 

 



70 

 75 

 55 

 60 

 70 

 75 

 60 

 80 

 75 

 60 

 50 

 75 

 75 

 70 

 70 

 60 

 50 

 80 

 75 

 70 

 80 

 65 



'Died, -' 10% Stage III ova in ovaries, not fertilized. 



^Plug formed, fish became bloated and hydrated to point of death. 



^Stage III ova in ovaries, not fertilized. 



"Plug formed, fish became bloated. 



nation for inducing spawning of yellowtail floun- 

 der. 



Larval Rearing 



Fertilized yellowtail flounder embryos were in- 

 cubated in 64-1, rectangular, black-sided, static, 

 well-aerated aquaria at a density of approxi- 

 mately 80 embryos/1. The incubating and rearing 

 temperature was 10°C and the salinity 32%o. 

 Banks of 40-W timed fluorescent lights suspended 

 1 m over the aquaria simulated a day and night 

 regimen of 15 h light and 9 h dark ( 15L:9D). The 



aquaria were inoculated with green algae 

 (Dunaliella sp.) which may have aided in the re- 

 moval of metabolic waste products produced by the 

 larvae. The algae also served to sustain the zoo- 

 plankton introduced as food. A single application 

 of penicillin (25 lU/ml) and streptomycin (0.02 

 mg/ml) was effective in controlling bacterial con- 

 tamination in almost all cases. 



At 10°C, hatching occurred 6-7 days after fertili- 

 zation. Yolk absorption occurred 4-5 days after 

 hatching, which coincided with first feeding. The 

 larvae averaged 2.75 mm long upon hatching and 

 possessed a completely formed gut. The eyes were 



934 



