The effects of light intensity on survival rate, fatness and maturity rate in conditioning broodstock of scally giant clam (Tridacna squamosa Lamarck, 1819)
Abstract
The study was conducted to evaluate the effect of light intensity on survival rate, fatness and reproductive maturity of scally giant clams (Tridacna squamosa Lamarck, 1819). Parent clams were raised for 50 days in 8 m3 cement tanks, with a stocking density of 2 clams/m2 of bottom area. The experimental design included three treatment groups, each subjected to different light intensities: 2.000 lux, 4.000 lux, and 6.000 lux. Each treatment was replicated 6 times. The results indicated that, after 50 days of cultivation, the parent clams exposed to a light intensity of 2,000 lux achieved the highest survival rate, fatness, and reproductive maturity, with values of 63,50 ± 0,58%, 19,25 ± 0,50%, and 52,75 ± 0,50%, respectively. The group exposed to the light intensity of 6.000 lux yielded the lowest results across all parameters, with a survival rate of 59,25 ± 1,27%, fatness of 15,25 ± 0,50% and reproductive maturity of 44,25 ± 0,50%.
