Optimal frame rate when there were stallion sperm motility evaluations and determinations for kinematic variables using CASA-Mot analysis in different counting chambers.

This study was conducted to determine optimum image capture frame rates (FRO) when there was evaluation of different types of counting chambers used for CASA-Mot determinations of stallion sperm motility. Sperm VCL was determined at frame rates of 25-250 f/s in: 1) Spermtrack® (Spk) 10 and 20 chambers (drop displacement-type chambers 10 and 20 μm-deep respectively; and 2) ISAS®D4C10, ISAS®D4C20 (10 and 20 μm-deep respectively) and ISAS®D4C20 L (20 μm-deep) capillary loaded chambers. Values for different sperm kinematic variables were determined using each chamber at 250 f/s, which is the maximum frame rate that the software can be used for analyses. With evaluation of Spk chambers, there was a greater curvilinear velocity (VCL), average path velocity (VAP), straight line velocity (STR), amplitude of lateral head displacement (ALH) and beat cross frequency (BCF) values (P < 0.05) than with capillary loaded chambers, with there being greatest values with 20 μm-deep chambers. With the Spk10 chamber, VCL and ALH were greater at the chamber centre than periphery. There were no such differences for the Spk20 chamber. With evaluation of the D4C10 chamber, VSL and STR were less when there was a sperm deposition point towards the chamber end, while there were the opposite for the D4C20 chamber. When there was evaluation of the D4C20 chamber, there were also greater VCL, WOB and BCF values in distal areas. With use of most of these chambers, data should be collected from different fields and means determined, however, this is not necessary with Spk20 chambers.