Submitted to: International Aquafeed Magazine
Publication Type: Trade Journal
Publication Acceptance Date: 5/21/2012
Publication Date: 6/1/2012
Citation: Chatakondi, N.G. 2012. Transfering vitamin C from fish to embryos. International Aquafeed Magazine. 15(3):8-10.
Interpretive Summary: Ascorbic acid is an essential micronutrient in the diet of teleost fish, which do not have gulonolactone oxidase activity. Vitamin C needs are higher for reproduction and early life stages of fish and these levels cannot be met by dietary administration alone apart from solubility and absorption of the nutrient. Intraperitoneal Injection of vitamin C to female broodfish prior to hormone-induced spawning invoked mass transfer of the nutrient to improve maturation and ovulation in broodfish and subsequently performance of the progeny. This strategy of mass transfer of vitamin C to the ontogeny improved growth, reduced mortalities to Edwardseilla ictaluri disease challenge with no additional improvement to low oxygen stress. The results of this study are important in broodstock management techniques aimed towards attaining maximum production of high quality eggs in catfish hatcheries.
Technical Abstract: Beneficial effects of ascorbic acid supplementation to broodstock of a select aquaculture species is well documented. At the present levels of feeding, dietary means of vitamin C does not meet the requirements for maturation, reproduction and needs of early life stages of larvae. In addition, this nutrient is water soluble and readily gets accumulated by other organs before reaching the ovary. For practical reasons, It is not possible to attain the desired level of a nutrient by conventional methods, hence innovative approaches are needed. Mass transfer of nutrients via injection into broodstock is a novel method. Two routes of maternal transfer of vitamin C in mature channel catfish, Ictalurus punctatus prior to hormone-induced spawning were explored as a strategy to incorporate the vitamin and to determine its effect on reproduction and progeny performance. The results of this study suggest injecting vitamin C prior to hormone-induce spawning, invokes transfer to eggs, improves reproductive performance, and may subsequently improve ontogeny performance. However, the effect of vitamin C diminished with age of the fish and also at more natural conditions. Our goal was to achieve predictable fish production of robust quality for healthy, efficient, higher surviving and able to adapt to common stressors and pathogens. Improvements can be made in this area by new knowledge-based advances in nutrient delivery systems that may create large improvements in terms of production, feed conversion and survival in aquaculture production.