title: Cryopreservation of kangaroo spermatozoa using alternative approaches that reduce cytotoxic exposure to glycerol.
abstract: Alternative techniques for the cryopreservation of kangaroo spermatozoa that reduced or eliminated the need for glycerol were investigated including; (1) freezing spermatozoa with 20% glycerol in pre-packaged 0.25 mL Cassou straws to enable rapid dilution of the glycerol post-thaw, (2) investigating the efficacy of 20% (v/v) dimethyl sulphoxide (DMSO) and dimethylacetamide (DMA-10%, 15% and 20% v/v) as cryoprotectants and (3) vitrification of spermatozoa with or without cryoprotectant (20% v/v glycerol, 20% v/v DMSO and 20% v/v DMA). Immediate in-straw post-thaw dilution of 20% glycerol and cryopreservation of spermatozoa in 20% DMSO produced no significant improvement in post-thaw viability of kangaroo spermatozoa. Spermatozoa frozen in 20% DMA showed post-thaw motility and plasma membrane integrity of 12.7+/-1.9% and 22.7+/-5.4%, respectively, while kangaroo spermatozoa frozen by ultra-rapid freezing techniques showed no evidence of post-thaw viability. The use of 10-20% DMA represents a modest but significant improvement in the development of a sperm cryopreservation procedure for kangaroos.
authors.affiliation: School of Animal Studies, The University of Queensland, Gatton Q 4343, Australia. rhettmcclean@gmail.com
authors.forename: Rhett
authors.initials: R
authors.lastname: McClean
authors.forename: Yeng Peng
authors.initials: YP
authors.lastname: Zee
authors.forename: William V
authors.initials: WV
authors.lastname: Holt
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Johnston
mesh_terms: D000081:Acetamides / Q000494:pharmacology; D000818:Animals; D002462:Cell Membrane / Q000187:drug effects; D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D005990:Glycerol / Q000494:pharmacology / Q000633:toxicity*; D007614:Macropodidae; D008297:Male; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility; D013094:Spermatozoa / Q000187:drug effects* / Q000648:ultrastructure
chemical_list: D000081:Acetamides; C013959:dimethylacetamide; D005990:Glycerol; D004121:Dimethyl Sulfoxide