title: Evaluation of ram semen quality using polyacrylamide gel instead of cervical mucus in the sperm penetration test.
abstract: Fertility is a very complex biological function that depends on several properties of the spermatozoa, including sperm motility. Two objectives are analyzed in this study: (1) Replace the cervical mucus by a synthetic medium in a sperm penetration test, and (2) evaluating the results of this test objectively analyzing the sperm number that migrates. In experiment 1, we have tested eight concentrations of acrylamide (1%-2%). Rheological properties of media were analyzed. The plastic straws, loaded with acrylamide, were placed vertically on the semen sample tube for 15 min at 39 °C. After, the acrylamides were placed, by segments of 5 mm, into wells of a 24-well plate, dyed with Hoechst 33342 and the number of spermatozoa were calculated by automated microscopy analysis. The 1.55% and 1.6% acrylamide gel showed a number of spermatozoa emigrating closer to that seen with natural mucus. In experiment 2, we applied the sperm penetration in acrylamide 1.6% and 1.55% using fresh semen and cooled semen at 15 °C and 5 °C. The spermatozoa counts were performed for each segment of 10 mm. Semen chilled at 15 °C presented intermediate values of sperm counts in comparison with fresh semen (higher) and 5 °C chilled semen. The sperm counts do not differ between acrylamides but the rheological properties of acrylamide 1.6% were more similar to those of the natural cervical mucus. In experiment 3, we have observed significant correlations between the number of spermatozoa and several sperm quality parameters (positive: progressive motility and velocity according to the straight path; negative: damaged acrosomes and apoptotic cells) in 1.6% acrylamide media. We conclude that the size of the cell subpopulation, objectively calculated, that migrate beyond 20 mm in 0.5-mL straws filled with acrylamide is a useful parameter in ram sperm quality assessment and further studies are needed to evaluate its relationship with field fertility.
authors.affiliation: ITRA-ULE, INDEGSAL, University of León, León, Spain. ppazc@unileon.es
authors.forename: C
authors.initials: C
authors.lastname: Martínez-Rodríguez
authors.forename: M
authors.initials: M
authors.lastname: Alvarez
authors.forename: L
authors.initials: L
authors.lastname: Ordás
authors.forename: C A
authors.initials: CA
authors.lastname: Chamorro
authors.forename: F
authors.initials: F
authors.lastname: Martinez-Pastor
authors.forename: L
authors.initials: L
authors.lastname: Anel
authors.forename: P
authors.initials: P
authors.lastname: de Paz
mesh_terms: D000177:Acrosome / Q000502:physiology; D000180:Acrylic Resins; D000818:Animals; D017209:Apoptosis; D002582:Cervix Mucus; D008297:Male; D008928:Mitochondria / Q000502:physiology; D055101:Semen Analysis / Q000379:methods / Q000662:veterinary*; D012756:Sheep / Q000502:physiology*; D013081:Sperm Motility; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology
chemical_list: D000180:Acrylic Resins; C016680:polyacrylamide gels