ABSTRACT
The objective was achieved by dividing the research into two experiments: (1) improving the freezing protocol using powdered coconut water (ACP-104) as a diluent for the cryopreservation seminal of common carp; (2) evaluating the effect of supplementation of vitamins C (ascorbic acid) or vitamin E (α-tocoferol) with the best extenders tested in experiment 1 on the quality of post-thawed. For experiment 1, semen pools from 14 selected males were formed. Seminal samples were evaluated for total motility, velocity, percentage of normal sperm and sperm vitality before and after the seminal cryopreservation. This was done in ACP-104 extender plus dimethyl sulfoxide (DMSO), or ethylene glycol (EG), or glycerol or methanol all at concentration 10% diluted in 1:3 (semen:extender). The samples were frozen in vapors of nitrogen into dry shippers and stored in liquid nitrogen (-196 °C). For experiment 2, eight pools were formed from the 15 males. The semen samples were evaluated following the same analysis of experiment 1 adding duration of total motility. The sperm cryopreservation was performed in extenders ACP-104 plus DMSO or EG supplemented or not with vitamin C or E. The best results found in Experiment 1 were obtained with DMSO and EG. They do not differ significantly for total motility (24% and 28%; P>0.05) and normal sperm (32% and 26%; P>0.05) respectively. For experiment 2, EG supplemented with vitamin E, produced significantly better results overall motility, sperm normality and duration of motility relative to DMSO. In conclusion, EG should be the cryoprotectant of choice for use with the ACP-104 supplemented or not with vitamin E.
Keywords:
Cyprinus carpio; sperm; cryopreservation; antioxidants; ACP-104