Biophysical Approaches to the 

 Measurement of Sperm Motility 



ROBERT RIKMENSPOEL* 



Johnson Foundation, University of Pennsylvania, Philadelphia, Pennsylvania 



The parameters of sperm motility and their methods of measure- 

 ment have already received considerable attention by a number of 

 investigators (see also Bishop, 1962). Essentially, two fundamental 

 kinds of problems are involved in the concept of sperm motility, 

 those associated with the nature of the mechanism of movement of 

 individual cells, and those concerned with the measurement of rele- 

 vant statistical quantities which characterize the "motility status" of 

 a semen sample. 



The experimental approach to each of these kinds of problems 

 will, of course, vary. For detailed observation of individual move- 

 ments, cinemicrographs of semen samples seem to be the best means 

 available. Measurement of statistical quantities, such as the mean 

 velocity and concentration, can be attempted only after establishing 

 that sperm cells obey appropriate statistical laws. This, too, is facili- 

 tated by means of cinemicrography. This paper will be devoted to 

 an account of recent experiments performed to elucidate some as- 

 pects connected with both sets of problems involved in sperm mo- 

 tility. 



SOURCE AND HANDLING OF MATERIAL 



Semen was obtained from bulls at the experimental farm of the 

 Research Institute for Animal Husbandry at De Bilt, Holland, and 

 from the Southeastern Pennsylvania Artificial Breeder's Cooperative 

 at Lancaster, Pennsylvania. 



After ejaculation, the semen was diluted XlO in optically clear, 



* Present address: Biophysics Laboratory, Stanford University, Stanford, Cali- 

 fornia. 



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