title: Sperm survival kinetics in different types of bull semen: progressive motility, plasma membrane integrity, acrosomal status and reactive oxygen species generation.
abstract: This study was designed to compare the kinetics of sperm survival in different types of bull semen. Fresh ejaculates from four bulls were pooled, diluted in Tris-citric acid-egg yolk-glycerol extender, cooled to 4°C, frozen in LN2 and thawed at 37°C. Fresh, diluted, cooled and frozen-thawed semen were incubated at 37°C, and evaluated at 0, 2, 4, 6, 12 and 24h after the beginning of incubation. In Experiment 1, progressive sperm motility, normal acrosomes and plasma membrane integrity and asymmetry were determined. In Experiment 2, generation of superoxide anion (O2(•)) along with plasma membrane permeability and generation of hydrogen peroxide (H2O2) along with plasma membrane integrity were assessed. In Experiment 1, frozen-thawed semen had shorter survival times for progressive sperm motility, and spermatozoa with intact plasma membranes and acrosomes (IPM-IACR) as compared with other types of semen (P<0.05). Fresh spermatozoa underwent a necrotic pathway, diluted and cooled spermatozoa underwent an apoptosis-like pathway and frozen-thawed spermatozoa underwent both necrotic and apoptosis-like pathways. In Experiment 2, spermatozoa in all four types of semen exhibited O2(•-) generation and increased plasma membrane permeability, and became necrotic without H2O2 generation during incubation (P<0.05). In conclusion, frozen-thawed semen had shorter sperm longevity, which has important implications relating to the timing of artificial insemination. Different types of semen followed different death pathways. During incubation, spermatozoa in all types of semen generated O2(•-), which increased the permeability and compromised the integrity of the plasma membrane.
authors.affiliation: Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7S 1K9, Canada.
authors.forename: Mushtaq
authors.initials: M
authors.lastname: Ahmad
authors.affiliation: Department of Theriogenology, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan.
authors.forename: Nasim
authors.initials: N
authors.lastname: Ahmad
authors.affiliation: Department of Theriogenology, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan.
authors.forename: Amjad
authors.initials: A
authors.lastname: Riaz
authors.affiliation: Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7S 1K9, Canada.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Anzar
mesh_terms: D000177:Acrosome / Q000502:physiology; D000818:Animals; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism; D002470:Cell Survival / Q000502:physiology*; D007700:Kinetics; D008297:Male; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012661:Semen / Q000502:physiology*; D012662:Semen Preservation; D013081:Sperm Motility / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology*; D013481:Superoxides / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D013481:Superoxides