Dietary administration of dehydroepiandrosterone hormone influences sex differentiation of hybrid red tilapia (O. niloticus x O. mossambicus) larvae
http://www.scialert.net/qredirect.php?doi=jfas.2012.447.453&linkid=pdf Abstract
Effects of a steroid hormone Dehydroepiandrosterone (DHEA) on sex differentiation of hybrid red Tilapia Oreochromis niloticus x O. mossambicus larvae were investigated. Three day-old tilapia larvae were fed diets supplemented with varying concentrations of DHEA (0, 20, 40, 80 and 160 mg kg-1 feed) for 24 days. A positive control group fed with diet containing 60 mg kg-1 of 17α-methyl testosterone was also included in the experimental run. Results indicate that among the DHEA treatment groups, larvae fed with 160 mg kg-1 DHEA showed the highest percentage of males that is comparable to the number of differentiated male fish observed in treatment group receiving the 17α-methyl testosterone as the positive control group. DHEA supplementation also improves weight gain and enhances feed conversion ratio. These findings suggest that DHEA can be used as a dietary supplement to induce masculinization and can improve the growth performance of tilapia larvae.
Citation
Mohamed, A. H., Traifalgar, R. F. M., Serrano Jr., A. E., Peralta, J. P., & Pedroso, F. L. (2012). Dietary administration of dehydroepiandrosterone hormone influences sex differentiation of hybrid red tilapia (O. niloticus x O. mossambicus) larvae.Publisher
Academic Journals, New YorkSubject
Acknowledgment/Sponsorship
This study was funded and supported by the Ministry of High Education and Scientific Research, Training and Extension Department through the efforts of Sudan University of Science and Technology-Sudan, under Scholarship Grant Permit No. 156/17A/5A/2009-2012.
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