title: Effect of freezing rate for cryopreservation of Persian sturgeon (Acipenser persicus) spermatozoa.
abstract: This study examined the effect of freezing rate (-10 °C, -15 °C, -20 °C, -30 °C, and -40 °C/min) on motility parameters, rates of fertilization and hatching, ATP content, and indices of oxidative stress including thiobarbituric acid reactive substances and carbonyl derivatives of proteins in Persian sturgeon (Acipenser persicus) sperm. After sampling, sperm was diluted in an extender composed of 23.4-mM sucrose, 0.25-mM KCl, and 30-mM Tris-HCl, pH 8.0, containing 10% methanol and subsequently frozen in a programmable freezer. For postthaw sperm that were frozen at a rate of -40 °C/min, sperm motile duration (134 ± 27.01 seconds), sperm motile percent (60 ± 4.1%), fertilizability (72 ± 8.36% for fertilization rate and 65 ± 7.58% for hatching rate), and ATP content (4.8 ± 0.57 nmol/10(8) sperm) were significantly higher than for sperm frozen at any of the four slower rates (P < 0.05). Moreover, sperm cryopreserved using the fastest freezing rate had significantly lower levels of thiobarbituric acid reactive substances (0.5 ± 0.05 nmol/10(8) sperm) and carbonyl derivatives of proteins (41.3 ± 4.9 nmol/10(8) sperm) than sperm cryopreserved using all other freezing rates (P < 0.05). In addition, there is a significant difference (P < 0.05) between fresh sperm and the recovery of cryopreserved Persian sturgeon sperm using programmable freezing with -40 °C/min being the optimal freezing rate among those tested.
authors.affiliation: Fisheries Department, Faculty of Natural Resources, Urmia University, Urmia, Iran. Electronic address: msaramli@gmail.com.
authors.forename: Mohammad Sadegh
authors.initials: MS
authors.lastname: Aramli
authors.affiliation: Young Researchers and Elites Club, North Tehran Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Karim
authors.initials: K
authors.lastname: Golshahi
authors.affiliation: Rajaei Sturgeon Hatchery Center, Sari, Iran.
authors.forename: Rajab Mohammad
authors.initials: RM
authors.lastname: Nazari
authors.affiliation: Fisheries Department, Faculty of Agriculture and Natural Resources, Persian Gulf University, Bushehr, Iran.
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Sotoudeh
authors.affiliation: Medicine Laboratory, Alavi Educational and Treatment Center, Ardabil University of Medical Sciences, Ardabil, Iran.
authors.forename: Salim
authors.initials: S
authors.lastname: Aramli
authors.affiliation: Biotechnology Laboratory, Faculty of Agriculture and Natural Resources, Tehran University, Karaj, Iran.
authors.forename: Ensieh
authors.initials: E
authors.lastname: Habibi
mesh_terms: D000818:Animals; D015925:Cryopreservation; D005399:Fishes / Q000502:physiology*; D008297:Male; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000502:physiology*; D013997:Time Factors
keywords: ATP; Cryopreservation; Fertility; Oxidative stress; Persian sturgeon; Sperm motility