The effect of the chamber on kinetic results in cryopreserved bull spermatozoa

Abstract

SUMMARYIn this study, the effect of the chamber used for the automated analysis of sperm motility by a computer-assisted semen analysis system on sperm kinematics was evaluated, and the cause of this effect was also verified. Twenty-three bull semen batches were thawed, and semen was diluted, aliquoted and analysed with six different chambers, (three capillary-loaded chambers and three droplet (DR)-loaded chambers). For each chamber type, each sample was analysed in quadruplicate, and the reliability of the analysis was tested using an intraclass correlation coefficient (ICC). Furthermore, sperm membrane integrity (MI) was evaluated, for each sample and chamber, in 12 randomly selected central and 12 edge fields. The ICC analysis showed that some parameters could have a significant variability related to the chamber. High stability of results was detected in Leja 4-chamber slide. Furthermore, as previously reported in other studies, capillary-loaded chambers seemed to affect the total and progressive motility and sperm velocities (average path velocity, straight line velocity and curvilinear velocity). These findings were corroborated by the evaluation of sperm MI that was significantly higher in the DR-loaded chambers. This study confirms that the chamber used for the objective kinetic evaluation of bull-thawed spermatozoa significantly affects the result. These differences could be present also in other species, even if the specific effect on the sperm kinematics should be verified. The Makler chamber seemed to give reliable results with negligible effects on sperm kinematics.

Influence of chamber type integrated with computer-assisted semen analysis (CASA) system on the results of boar semen evaluation

“…are still commonly considered as one of the most important parameters of semen quality, have been assessed in recent decades using new techniques that offer more accurate and reliable information, especially with regard to the subjective methods of light microscopy (Mortimer et al 2000, Maes et al 2010, Hoogewijs et al 2012, Gloria et al 2013. A promising alternative to conventional methods of visualization of sperm motility or concentration is the use of computer-assisted semen analysis (CASA) systems.…”

“…Although CASA systems operate on similar principles, they differ in terms of optics and hardware characteristics, as well as algorithms for sperm identification and trajectory reconstruction (Contri et al 2010, Hoogewijs et al 2012. Therefore, for CASA-obtained data on motility to be reliable, this type of equipment must be present and the measurement procedure standardized (Mortimer et al 2000, Rijsselaere et al 2003, Contri et al 2010, Gloria et al 2013. Of great importance is proper definition of the criteria connected with sperm characteristics specific to a species, the technical settings of CASA systems (e.g., the frequency of frame acquisition, the number of fields analysed and time of analysis), and the preparation of semen for analysis (Verstegen et al 2002, Contri et al 2010, Broekhuijse et al 2011.…”

“…Of great importance is proper definition of the criteria connected with sperm characteristics specific to a species, the technical settings of CASA systems (e.g., the frequency of frame acquisition, the number of fields analysed and time of analysis), and the preparation of semen for analysis (Verstegen et al 2002, Contri et al 2010, Broekhuijse et al 2011. It has been recognized in recent years that CASA assessment of sperm motility or concentration can be significantly influenced by the type of chamber used for the analysis (Contri et al 2010, Hoogewijs et al 2012, Gloria et al 2013, Palacín et al 2013. The different types of chambers used on the CASA systems differ in terms of depth, size, shape and loading modality, which is often dependent on the volume of semen analysed (Hoogewijs et al 2012, Gloria et al 2013).…”

“…It has been recognized in recent years that CASA assessment of sperm motility or concentration can be significantly influenced by the type of chamber used for the analysis (Contri et al 2010, Hoogewijs et al 2012, Gloria et al 2013, Palacín et al 2013. The different types of chambers used on the CASA systems differ in terms of depth, size, shape and loading modality, which is often dependent on the volume of semen analysed (Hoogewijs et al 2012, Gloria et al 2013). The possibility of using different chambers may hinder the identification and quantification of factors potentially affecting CASA outcomes, and there is also a need to harmonize and standardize laboratory procedures used during CASA assessment for each species (Rijsselaere et al 2003, Broekhuijse et al 2011, Gloria et al 2013.…”

“…The possibility of using different chambers may hinder the identification and quantification of factors potentially affecting CASA outcomes, and there is also a need to harmonize and standardize laboratory procedures used during CASA assessment for each species (Rijsselaere et al 2003, Broekhuijse et al 2011, Gloria et al 2013. In a previous research, the effect of the type of chamber used has been studied both in man (Le Lannou et al 1992) and in some animal species such as bulls (Contri et al 2010, Lenz et al 2011, Gloria et al 2013, rams (Palacín et al 2013), horses (Hoogewijs et al 2012), rabbits (Massányi et al 2008) and dogs (Iguer-Ouada and Verstegen 2001). However, little is known about the effect of different chambers designed for CASA analysis on the sperm concentration and especially on kinetic evaluation of boar spermatozoa.…”