title: Effect of cryoprotectants on the survival of cascudo preto (Rhinelepis aspera) embryos stored at -8 °C.
abstract: Cryopreservation of germplasm provides a promising method to preserve fish genetic material, which is of great importance in preservation of species diversity, aquaculture, and management of fish models used in biomedical research. In the present study, cryopreservation of Rhinelepis aspera embryos, a Brazilian endangered species, was studied for the first time using a short-term cooling protocol. Embryos at blastoporous closing stage were selected, placed in 6-ml glass vials and stored at -8 °C for 6 h in 10 different cryoprotectant solutions: S1 (17.1% sucrose + 9% methanol); S2 (17.1% sucrose + 9% DMSO); S3 (8.5% sucrose + 8.5% glucose + 9% methanol); S4 (8.5% sucrose + 8.5% glucose + 9% DMSO); S5 (17.1% sucrose + 9% ethylene glycol); S6 (8.5% sucrose + 8.5% glucose + 9% ethylene glycol); S7 (17.1% sucrose + 4.5% methanol + 4.5% DMSO); S8 (17.1% sucrose + 4.5% methanol + 4.5% ethylene glycol); S9 (17.1% sucrose + 4.5% DMSO + 4.5% ethylene glycol); and S10 (100% water). Embryo viability was assessed by hatching rate, counting live larvae and number of failed eggs under a stereomicroscope. The results showed that only the cryoprotectant solutions that contained methanol associated to sucrose (S1, S7 and S8) provided partial protection of Rhinelepis aspera embryos from cold damage (over 50% hatching rate in S1), while the use of DMSO and ethylene glycol, isolated or in combination, resulted in no hatching rate. Further studies are needed in order to extend the storage time and to improve the hatching rate for the species.
authors.affiliation: Departamento de Zootecnia, Universidade Estadual de Maringá, Av. Colombo 5790, CEP 87020-900, Maringá-PR, Brazil.
authors.forename: Darci Carlos
authors.initials: DC
authors.lastname: Fornari
authors.affiliation: PeixeGen Research Group, Maringa State University, Department of Animal Science, Maringa, Brazil.
authors.forename: Ricardo Pereira
authors.initials: RP
authors.lastname: Ribeiro
authors.affiliation: Aquam Research Group, Federal University of Rio Grande do Sul, Department of Animal Science, Porto Alegre, Brazil.
authors.forename: Danilo
authors.initials: D
authors.lastname: Streit
authors.affiliation: Aquam Research Group, Federal University of Rio Grande do Sul, Department of Animal Science, Porto Alegre, Brazil.
authors.forename: Leandro Cesar
authors.initials: LC
authors.lastname: Godoy
authors.affiliation: Ponta Grossa State University, Department of Animal Science, Ponta Grossa, Brazil.
authors.forename: Patrícia Ribeiro
authors.initials: PR
authors.lastname: Neves
authors.affiliation: Aquam Research Group, Federal University of Rio Grande do Sul, Department of Animal Science, Porto Alegre, Brazil.
authors.forename: Diego
authors.initials: D
authors.lastname: de Oliveira
authors.affiliation: Environment manager, CPFL Energy, São Paulo, Brazil.
authors.forename: Rodolfo Nardez
authors.initials: RN
authors.lastname: Sirol
mesh_terms: D000818:Animals; D017756:Aquaculture; D001938:Brazil; D002397:Catfishes / Q000196:embryology*; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000187:drug effects; D047108:Embryonic Development / Q000187:drug effects*; D019855:Ethylene Glycol / Q000494:pharmacology; D000432:Methanol / Q000494:pharmacology; D013395:Sucrose / Q000494:pharmacology
chemical_list: D003451:Cryoprotective Agents; D013395:Sucrose; D019855:Ethylene Glycol; D000432:Methanol