title: Motility and fertility of rabbit sperm cryopreserved using soybean lecithin as an alternative to egg yolk.
abstract: This study was conducted to investigate whether soy lecithin can be used as an alternative cryoprotectant to establish a procedure that does not require the use of egg yolk to cryopreserve rabbit strains. Semen from Japanese White rabbits was frozen with HEPES extender containing 20% egg yolk (EYH), 0.5% (Lec-0.5), 1.5% (Lec-1.5), 2.5% (Lec-2.5), or 3.5% (Lec-3.5; wt/vol) lecithin (type IV-S, ≥30%), and the motility of thawed sperm was analyzed. The sperm motility in the Lec-1.5 group was significantly higher than that in the Lec-2.5 and 3.5 groups and equivalent to the EYH group. From 17 rounds of artificial insemination with frozen-thawed sperm in the EYH and Lec-1.5 groups, 12 rabbits in both groups were pregnant (70.6%) and delivered offspring. The litter size was 3.3 in the EYH group and 5.1 in the Lec-1.5 group. These results indicate that soy lecithin can be used as a substitute for egg yolk as a cryoprotectant on the basis of motility and fertility of the frozen-thawed rabbit sperm and that 1.5% lecithin (type IV-S, ≥30%) in the semen extender was the optimum concentration for rabbit sperm cryopreservation.
authors.affiliation: Animal Research Laboratory, Bioscience Education-Research Center, Akita University, Akita, Japan. Electronic address: kanish@gipc.akita-u.ac.jp.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Nishijima
authors.affiliation: Division of Biological Resources and Development, Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan.
authors.forename: Shuji
authors.initials: S
authors.lastname: Kitajima
authors.affiliation: Division of Bio-Resources, Department of Biotechnology, Frontier Science Research Center, University of Miyazaki, Miyazaki, Japan.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Koshimoto
authors.affiliation: Division of Biological Resources and Development, Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Morimoto
authors.affiliation: Division of Biological Resources and Development, Analytical Research Center for Experimental Sciences, Saga University, Saga, Japan.
authors.forename: Teruo
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Molecular Pathology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan.
authors.forename: Jianglin
authors.initials: J
authors.lastname: Fan
authors.affiliation: Animal Research Laboratory, Bioscience Education-Research Center, Akita University, Akita, Japan.
authors.forename: Yukihisa
authors.initials: Y
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary; D003451:Cryoprotective Agents; D004530:Egg Yolk; D005260:Female; D005298:Fertility; D007315:Insemination, Artificial / Q000662:veterinary; D008098:Litter Size; D008297:Male; D010713:Phosphatidylcholines; D011247:Pregnancy; D011817:Rabbits; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology
chemical_list: D003451:Cryoprotective Agents; D010713:Phosphatidylcholines; C024990:asolectin
keywords: Cryoprotectant; Fertility; Soybean lecithin; Sperm cryopreservation