Cryopreservation of sperm in Brazilian migratory fish conservation
Abstract:Simple, effective protocols for cryopreserving milt of five Brazilian migratory characids (Brycon orbignyanus, Prochilodus lineatus, Piaractus mesopotamicus, Salminus maxillosus and Leporinus elongatus) and one Brazilian migratory catfish (Pseudoplatystoma corruscans) are described. Milt was frozen and stored in dry shippers immediately after collection, making the procedure practical for use in the field. A diluent of 5% glucose, 10% dimethyl sulphoxide and 10% egg yolk was effective for all of the characid species, and a diluent of 10% methanol and 15% powdered milk was effective for P. corruscans. Milt was thawed in an ambient temperature water bath (28–30° C). Activation of thawed milt was effective with either saline (0·9 or 0·45% NaCl) or bicarbonate (1% NaHCO3). Fertilization rates with frozen milt varied between 49 and 300% of the control. Application of the technology for increasing genetic diversity in hatchery programmes for enhancement, mitigation or conservation breeding is discussed, as is its application in aquaculture. Inappropriate use of the technology can threaten wild biodiversity and appropriate legislation and education may be required for its responsible use.
Document Type: Regular Paper
Affiliations: 1: World Fisheries Trust, 204-1208 Wharf St., Victoria, BC, V8W 3B9 Canada, 2: PUC-Minas, Av. Dom José Gaspar, 500 Prédio 41, 30535-610 Belo Horizonte, MG, Brasil and 3: Departmento de Aqüicultura, Universidade Federal de Santa Catarina, C.P. 476, 88010-970 Florianópolis, SC, Brasil
Publication date: August 1, 2003