TY - JOUR ID - 63763 TI - High dilution rate of bull semen affects cryopreservation outcomes: kinematic and flowcytometric parameters JO - Iranian Journal of Veterinary Medicine JA - IJVM LA - en SN - 2251-8894 AU - Hussaini, Sayed Mohammad Hadi AU - Zhandi, Mahdi AU - زارع شحنه, احمد AU - Sharafi, Mohsen AD - Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran AD - Department of Poultry Sciences, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran Department of Embryology at Reproduction Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACER, Tehran, Iran Y1 - 2017 PY - 2017 VL - 11 IS - 4 SP - 377 EP - 383 KW - Bovine KW - concentration KW - Flowcytometry KW - Freezing KW - Sperm DO - 10.22059/ijvm.2017.225373.1004790 N2 - BACKGROUND: Semen cryopreservation might be influenced by sperm concentration. OBJECTIVES: This study was conducted to investigate three different semen concentrations [100 (C100), 50 (C50), and 25 (C25) × 106 spermatozoa/mL] on freezability of bull semen. METHODS: On each collection day, four ejaculates were collected (a total of 24 ejaculates from four bulls), pooled and divided to three equal parts. Each part was diluted to reach to one of the above mentioned final semen concentration and then frozen. After thawing, sperm motility, apoptosis status and mitochondrial activity were assessed. RESULTS: The results showed that C100 resulted in significantly higher total sperm motility compared to C50 and C25 groups. The percentage of live spermatozoa was significantly higher in C100 compared to C50 and C25 groups. Also, C25 resulted in significantly higher early and late apoptotic spermatozoa compared to C50 and C100 groups. The mitochondrial activity was significantly lower in C25 compared to C100 and C50 groups. CONCLUSIONS: It seems that low sperm concentrations (as low as 50×106) may be less advantageous for cryopreservation. UR - https://ijvm.ut.ac.ir/article_63763.html L1 - https://ijvm.ut.ac.ir/article_63763_a718b4bb27cb61ab0f9da9c5cec7d3f4.pdf ER -