Comparison of DNA Fragmentation Assay in Frozen-Thawed Cat Epididymal Sperm

Technical Evaluation of Commercial Sperm DFI Quality Control Products in SCSA Testing

With the increase in population and the advancement of medicine, people even more hope that their offspring will be healthier. DNA fragmentation rate is currently one of the more common indicators for evaluating sperm fertility and predicting the outcome of pregnancy. In order to evaluate the technical performance and application value of commercial sperm DFI (DNA fragmentation index) quality control products in the flow cytometry sperm chromatin structure analysis (SCSA), this paper uses flow cytometry to test commercial sperm DFI quality control products (Celula) and laboratory routine self-made DFI quality control products. In this paper, the quality control of new commercial sperm DFI and laboratory-made quality control were compared and tested for 30 consecutive days. And this paper monitors the response of commercial quality control products to the interference of key reagent parameters. This paper compares the stability of the test results of two quality control products and their sensitivity to the interference of key performance parameters of the detection reagent. Experimental results show that commercial sperm DFI quality control products can simulate sperm DNA damage to achieve accurate detection of DNA integrity. The stability of commercial sperm DFI quality control (CV = 2.47%) is better than that of laboratory-made quality control (CV = 11.22%). The new commercial sperm DFI quality control product can sensitively detect changes in the concentration of acidified solution and staining solution at the same time. It can effectively control the quality of detection reagents and experimental procedures. The new commercial sperm DFI quality control product can effectively control sperm DNA integrity testing. It can be used as an external quality control product for quality control of test results to ensure that more accurate test results are provided to the clinic.

Canine and Feline Epididymal Semen-A Plentiful Source of Gametes

Simple Summary

The epididymis is a source of fertile spermatozoa. For some males, preserving spermatozoa that are stored in the epididymis might be an ultimate attempt for gamete preservation. The quality of epididymal semen is different from ejaculated semen in various animal species. Although assisted reproductive technologies (ART) have been introduced in cats as a tool to preserve valuable genetics of endangered wild felids, epididymal semen cryopreservation is still suboptimal in dogs. Therefore, in this paper, we carried out a review to list the morphological changes of spermatozoa during epididymal transit alongside with the potential that holds in the epididymal semen in dogs and cats. We believe that better comprehension of epididymal semen collection method, quality and freezability may aid in optimizing cryopreservation and enhance different applications of ART.

Abstract

Canine and feline epididymal semen provide an additional source of gametes to preserve the genetics of valuable breeding dogs and tomcats, especially for those that fail to ejaculate, need castration as a therapy or die unexpectedly. Moreover, since it is quite common to perform castration of non-breeding dogs and cats, the development of a gene bank of epididymal semen collected after castration would greatly contribute to increase the genetic diversity in dogs and cats. Collection and cryopreservation of epididymal semen necessitates a full understanding of the function of the epididymis and of the characteristics of epididymal spermatozoa as opposed to ejaculated semen. During collection of epididymal semen, specific factors may have a negative effect on epididymal semen quality and freezability. Accordingly, the elimination of these triggers could enhance epididymal semen freezability and consequently positively influence post-thaw semen quality and outcome for different ARTs.

Sperm chromatin structure assay versus sperm chromatin dispersion kits: Technical repeatability and choice of assisted reproductive technology procedure

Objective

The sperm DNA fragmentation index (DFI) guides the clinician’s choice of an appropriate assisted reproductive technology (ART) procedure. The DFI can be determined using commercially available methodologies, including sperm chromatin dispersion (SCD) kits and sperm chromatin structure assay (SCSA). Currently, when DFI is evaluated using SCD kits, the result is analyzed in reference to the SCSA-derived threshold for the choice of an ART procedure. In this study, we compared DFI values obtained using SCSA with those obtained using SCD and determined whether the difference affects the choice of ART procedure.

Methods

We compared SCSA to two SCD kits, CANfrag (n=36) and Halosperm (n=31), to assess the DFI values obtained, the correlations between tests, the technical repeatability, and the impact of DFI on the choice of ART.

Results

We obtained higher median DFI values using SCD kits than when using SCSA, and this difference was significant for the CANfrag kit (p<0.001). The SCD kits had significantly higher coefficients of variation than SCSA (p<0.001). In vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) would be chosen for a significantly higher proportion of patients if a decision were made based on DFI derived from SCD rather than DFI determined using SCSA (p=0.003).

Conclusion

Our results indicate that SCD kit-specific thresholds should be established in order to avoid the unnecessary use of IVF/ICSI based on sperm DNA damage for the management of infertility. Appropriate measures should be taken to mitigate the increased variability inherent to the methods used in these tests.