The effect of Vitamin E, Vitamin C on viability and performance of cryopreserved African Catfish (c.gariepinus) sperm.

A dissertation submitted to the Directorate of Research & Graduate Training in partial fulfilment of the requirements for the award of a Master of Science in livestock development and management of Makerere University

This study aimed to examine the effects of vitamin E and C supplementation on the viability of cryopreserved C. gariepinus sperm cells, fertility, and hatchability of the fish eggs. Sperm samples were collected from 30 C. gariepinus male broodstock and diluted in Ringers solution, mixed with cryoprotectants (DMSO 5%) and varying concentrations of Vitamin E 0iu, Vitamin E 5iu, Vitamin E10iu) and vitamin C 0iu, Vitamin C 5iu, Vitamin C 10iu) in triplicates. The diluted milt was then frozen in a deep freezer (-4oc to -175oc) and placed in a liquid nitrogen flask for cryopreservation (- 196o c) Thawing was done at 370c for 5 minutes, fertilization was determined by mixing 10grams of female ripe C. gariepinus broodstock with 2-4 straws of thawed cryopreserved sperms and hatchability was also determined by subtracting hatched fry from dead fry expressed as a percentage. The results of this study showed that Vitamin C concentrations caused 100% mortality of all the sperm cells while supplementation of C. gariepinus milt with Vitamin E10iu had a significant reduction in motility with a p = 0.003, while 5iu had a marginal significance with a p = 0.053. Supplementation of milt with E10iu was found to reduce fertility loss. Furthermore, the highest fertilization and hatching percentages were observed when using 4 semen straws (0.25ml) on 8000 eggs and the addition of E10iu to the spermatozoa showed a marked significant hatchability (p < 0.001) With survival probability. Finally, the results showed that there’s an economic efficiency of using cryopreserved sperms. It needs only 0.0297 $ to produce a 0.25ml packed sperm straw. In conclusion, the results of the present study demonstrate that E10iu can improve the viability of cryopreserved C. gariepinus sperms, reduce fertility loss, and increase the hatchability and survival rate of the fry. Therefore, supplementation of E10iu in cryopreservation of C. gariepinus sperm cells can be used as an effective method of artificial breeding and long-term preservation of the genetic material in African Catfish.

National Agricultural Research Organization (NARO) National Fisheries Resources Research Institute- Aquaculture Research and Development Center (NAFIRRI- ARDC)