ABSTRACT
Gouramis require soft and acidic waters for optimal development, and in this context, a cheap and effective culture medium is required. In this study, Pearl and Blue gourami larvae were raised in Terminalia catappa leaf extract (TCE), clear water, and green water, the latter containing 1 × 105 cells/ml Chlorella from Tilapia cultures. Larval survival and specific growth rate (SGR) were determined after 10 days of incubation. TCE was most effective in promoting survival of both gourami species, with the number of viable larvae augmented twofold and 30% in comparison to clear water and green water respectively. TCE was acidic, and this may have played a significant role in boosting survival, although larvae potentially benefited from the antioxidant and therapeutic properties of TCE. TCE significantly boosted growth, as evidenced by a significant increase in the specific growth rate, perhaps explained by the occurrence of additional live food such as Paramecium, Colpidium, and other infusorians. Although the effects of TCE are uncertain, its application enhanced larval performance of gouramis and perhaps blackwater fishes, a finding with potential application in aquaculture.
Acknowledgments
We thank Dr. Tom MacRae, Department of Biology, Dalhousie University, Canada, for assistance in preparation of the manuscript.