Resfriamento de espermatóforos e inseminação assistida em camarão marinho Penaeus vannamei (Boone, 1931)

Abstract

The coldstorage of spermatophores of the shrimp Penaeus vannameifor the purpose of assisted insemination allowsthe transit of gametes between breeding laboratories, without transporting the animal, facilitating the exchange of genetic material and the use of genetically improved strains. The present work performed the cooling of P. vannameispermatophores to 15 ° C for 24 and 48 hours. Three extenderswere evaluated: Coconut Water Powder (ACP), Mineral Oil (OM) and Sterilized Sea Water (AME). Microscopic analyzes were performed to verify the apparent viability, through the analysis of membrane integrity with eosin-nigrosine and sperm morphology. Assisted insemination was performed after both periods of cooling. No statistical interaction was observed between the 24-and 48-hour cooling times. For apparent viability and morphology, the percentages of viable and morphologically normal cells remained above 60% and 70%, respectively, in all treatments and in both evaluated cooling times. When evaluating the extender, 74.9 ± 9.20, 77.3 ± 9.40 and 78.1 ± 6.35% of normal cells were observed in the OM, AME and ACP treatments, respectively. The highest average hatching rate was 80.67 ± 12.01%, observed in the AME treatment, which was higher than that observed for the ACP treatment, with 50.15 ± 20.75%. The hatching rate obtained by OM treatment was 71.47 ± 18.83%. The spermatophores of P. vannamei are capable of maintaining good rates of apparent viability, normal morphology and hatching after 48 hours of storage at 15 ° C in mineral oil, sea water or ACP®. Sterilized sea water is the most efficient diluent, as it resulted in ahigher hatching rate after artificial insemination.