Morphometry of stallion spermatozoa by computer-assisted image analysis

B. A. Ball, H. O. Mohammed

Research output: Contribution to journalArticlepeer-review

61 Scopus citations


Metric measurements of stallion spermatozoal heads were determined for live, unfixed spermatozoa and for Feulgen-stained spermatozoa by videomicroscopy and computerized image analysis. Two ejaculates were collected from each of five stallions of normal fertility. Air-dried semen smears were Feulgen-stained, and live, unfixed spermatozoa were examined as wet-mount preparations. For Feulgen-stained spermatozoa, videoimages (x3850) were captured, and sperm heads were detected via image segmentation and particle analysis. For live, unfixed spermatozoa, phase contrast videoimages (x3850) were measured to determine width and length of the sperm head. For Feulgen-stained spermatozoa, there were significant effects (P < 0.001) of stallion and ejaculate on measured parameters of area, circumference, and the length and width of the sperm head. For live, unfixed spermatozoa, there were significant effects of stallion on length and width and of ejaculate on length of the sperm heads. There was a very poor correlation between length and width of sperm heads between Feulgen-stained and live, unfixed spermatozoa. Two indices of sperm shape (oval factor and aspect ratio) were also determined. Both aspect ratio and oval factor were significantly affected by stallion (P < 0.001); however, oval factor was not affected by ejaculate and therefore may represent a less variable determination of sperm head shape across stallions. Overall, length and width of stallion sperm heads were larger (P < 0.01) for live, unfixed spermatozoa than for Feulgen-stained spermatozoa (length: 6.3 ± 0.4 vs 5.08 ± 0.44; width: 3.08 ± 0.34 vs 2.71 ± 0.28 μm, respectively). Computerized image analysis may be useful as a means to objectively measure sperm head dimensions in the stallion and could be useful in future studies to determine associations with stallion fertility.

Original languageEnglish
Pages (from-to)367-377
Number of pages11
Issue number3
StatePublished - Aug 1995

Bibliographical note

Funding Information:
This research was supported by the Harry M. Zweig Memorial Fund for Equine Research and Thornbrook Farms. The authors thank M. Lillard for technical assistance and P. G. A. Thomas and I. Dobrinski for a review of the manuscript.


  • equine
  • image analysis
  • measurement
  • sperm head
  • spermatozoa

ASJC Scopus subject areas

  • Small Animals
  • Food Animals
  • Animal Science and Zoology
  • Equine


Dive into the research topics of 'Morphometry of stallion spermatozoa by computer-assisted image analysis'. Together they form a unique fingerprint.

Cite this