Sperm morphology differences associated with pig fertility

Mandawala, A. A.; Skinner, B. M.; Walling, G. A.; Harvey, K. E. and Harvey, S.C. (2022). Sperm morphology differences associated with pig fertility. bioRxiv, article no. 314708.

DOI: https://doi.org/10.1101/314708

Abstract

Artificial insemination is routine in commercial pig breeding, and as such, the use of high-quality semen samples is imperative. Here, we have developed a novel, semi-automated, software-based approach to assess pig sperm nucleus morphology in greater detail than was previously possible. This analysis identified subtle morphological differences between samples assessed by the industry as normal and those assessed as abnormal. 50 normal and 50 abnormal samples that were initially categorised using manual assessment to industry standards, were investigated using this new method, with at least 200 fixed stained sperm heads analysed in each case. Differences in sperm nuclear morphology were observed between normal and abnormal samples; specifically, normal samples were associated with higher mean nuclear area, a consequence of a greater head width and a lower variability between sperm heads. This novel, unbiased and fast analysis method demonstrates a significant difference in sperm head morphology between normal and abnormal pig sperm and has the potential to be further developed to be used as a tool for sperm morphology assessment both in the pig breeding industry and potentially in human assisted reproductive technologies.