title: The cryopreservation of spermatozoa of the burbot, Lota lota (Gadidae, Teleostei).
abstract: The cryopreservation of spermatozoa of a teleost fish, the burbot, Lota lota (Gadidae) was investigated. Cryopreserved semen had the highest motility rate (46.6+/-8.0%, fresh semen control 86.5+/-8.2%) and fertility (78.1+/-2.7% embryo survival in hatching stage, fresh semen control 82.2+/-2.9%) when 10% methanol, 1.5% glucose and 7% hen egg yolk were used as cryoprotectants. Freezing was performed in 0.5-ml straws in the vapour of liquid nitrogen at 1cm above the level of liquid nitrogen and thawing in water at 25 degrees C for 20s. For optimal fertilization cryopreserved semen was first mixed with the eggs and then 25 or 50 mmol/L NaCl solution (pH 8.5) was added at a ratio of 1:24 (semen:saline solution). Under these conditions fertilization ratios in the range of fresh semen control were obtained at minimal sperm to egg ratios of 1.7 x 10(6):1. Fertilization with cryopreserved semen had no influence on the embryonic development, as the ratio of embryos which stopped development and the ratio of embryonic malformations were similar to fresh semen.
authors.affiliation: Institute for Zoology, University of Salzburg, Hellbrunnerstr. 34, 5020 Salzburg, Austria. franz.lahnsteiner@sbg.ac.at
authors.forename: Franz
authors.initials: F
authors.lastname: Lahnsteiner
authors.forename: Nabil
authors.initials: N
authors.lastname: Mansour
authors.forename: Thomas
authors.initials: T
authors.lastname: Weismann
mesh_terms: D000818:Animals; D017756:Aquaculture; D015925:Cryopreservation; D047108:Embryonic Development; D005260:Female; D005306:Fertilization; D005399:Fishes / Q000196:embryology; D008297:Male; D013081:Sperm Motility; D013094:Spermatozoa / Q000166:cytology*