Do conventional CASA-parameters reflect recovery of kinematics after freezing? CASA paradox in the analysis of recovery of spermatozoa after cryopreservation.
Conventional kinematic parameters (KPs) are averages of values obtained from analysing the entire motile fraction of cells in a sample. Occasionally, in spite of overall deterioration of semen samples after cryopreservation and other 'damaging' manipulations, the average relative (derived) KPs such as linearity (LIN), dance (DNC), dance mean (DNM) etc., may show apparently elevated values. Similarly, the absolute (actual) KPs such as straight line velocity (VSL), curvilinear velocity (VCL), average velocity path (VAP), average lateral head displacement (ALH), beat-cross frequency (BCF), etc., may also be higher after damaging treatments depending on the tolerance of various sub-populations in a single sample. The conditions for this CASA-paradox are discussed. Simple modifications of actual CASA-parameters are proposed to correct the pseudo-enhancement of kinematics characteristics in processed semen samples
Katkov
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Universal Preservation Technologies, Inc., 11045 Roselle Str., Suite C, San Diego, CA 92121, USA igork@uptsd.com
Lulat
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