title: The advantages of combining low-density lipoproteins with glutamine for cryopreservation of canine semen.
abstract: Twenty sperm samples from five dogs were frozen in liquid nitrogen at -196 degrees C in 16 different media, two control media containing 20% egg yolk and 6% low-density lipoproteins (LDL); 10 test media containing 6% LDL (the active cryoprotective ingredient of chicken egg yolk) combined with 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 mmol of glutamine respectively at 4%, 5%, 7%, and 8% LDL. Following thawing, sperm mobility was assessed using an image analyser, HAMILTON THORN CERROS 12. The percentage of mobile spermatozoa was 62.05% in the 6% LDL + 20 mmol glutamine medium compared with 48.90% in the egg yolk-based medium (p < 0.05) or 57.55% for the 6% LDL medium (p < 0.05). Furthermore, in most cases, the motility parameters (average path velocity, curvilinear velocity, straight line velocity) in the 6% LDL + 20 mmol glutamine medium, were superior, to a statistically significant extent, to those in the control media. Finally, the 6% LDL + 20 mmol glutamine combination provides spermatozoa with better protection during freezing than egg yolk or the 6% LDL medium alone in terms of acrosome integrity (fluorescein isothiocyanate--Pisum sativum agglutinin test: p < 0.05), the flagellar plasma membrane (hypo-osmotic test: p < 0.05 for 6% LDL), the DNA (acridine orange test; no significant difference) and the integrity of the acrosome (Spermac test: no significant difference).
authors.affiliation: Laboratory of Biotechnology and Pathology of Reproduction, National Veterinary School of Nantes, Nantes, France. bencharif@vet-nantes.fr
authors.forename: D
authors.initials: D
authors.lastname: Bencharif
authors.forename: L
authors.initials: L
authors.lastname: Amirat
authors.forename: O
authors.initials: O
authors.lastname: Pascal
authors.forename: M
authors.initials: M
authors.lastname: Anton
authors.forename: E
authors.initials: E
authors.lastname: Schmitt
authors.forename: S
authors.initials: S
authors.lastname: Desherces
authors.forename: G
authors.initials: G
authors.lastname: Delhomme
authors.forename: M-L
authors.initials: ML
authors.lastname: Langlois
authors.forename: P
authors.initials: P
authors.lastname: Barrière
authors.forename: M
authors.initials: M
authors.lastname: Larrat
authors.forename: D
authors.initials: D
authors.lastname: Tainturier
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D003451:Cryoprotective Agents / Q000494:pharmacology; D004285:Dogs / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005973:Glutamine / Q000494:pharmacology*; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D008297:Male; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000166:cytology / Q000187:drug effects / Q000502:physiology
chemical_list: D003451:Cryoprotective Agents; D008077:Lipoproteins, LDL; D005973:Glutamine