The integrity of sperm nuclear DNA is considered an important factor in male fertility. Studies in human sperm have suggested that the percentage of sperm containing fragmented DNA could be utilised as a potential predictor of fertility. The objectives of the present study were: (1) adapt the sperm chromatin dispersion (SCD) assay to analyse DNA fragmentation in bull sperm and (2) evaluate any potential correlation between sperm DNA fragmentation and bull fertility as measured by the field non-return rate (NRR). To adapt the SCD assay method, fresh or frozen-thawed bull sperm cells were immersed in an agarose matrix on a slide, treated with a mild acid solution to denature DNA, followed by treatment with a lysing buffer to remove nuclear proteins and subsequent Wright-Giemsa staining. Removal of nuclear proteins produced nucleoids with large halos of spreading DNA loops emerging from a central core in the absence of significant DNA breakage. In contrast, sperm nucleoids with elevated DNA fragmentation failed to produce a dispersion halo. Sperm cells with completely fragmented DNA were generated by incubation at 100^◦C for 30 minutes and were served as an effective positive control.  The adapted SCD assay was then applied to analyse the status of DNA fragmentation of sperm from bulls with high and low field NRR records.  Initial results comparing high versus low NRR bulls (-6% NRR) showed differences in the percentage of sperm DNA fragmentation, however further investigation is ongoing to determine whether these differences are statistically attributed to bull NRR.