NOTES.
A MEASURE FOR THE FERTILITY OF SPERM
Skandinavisk Veterinartidskrift, Uppsala, 1942
T HE usual measures employed in estimating the concentration and the motility of
spermatozoa often have resulted in misleading conclusions, because, while it is fairly easy
to use a counting chamber to determine concentration, it is very difficult to make an accurate
estimate of the number of cells that are truly motile.
Recent investigations indicate that the energy needed by the spermatozoa for movement
is derived chiefly from the process of anaerobic metabolism, and that the intensity of this
metabolism can be measured by the dehydrogenization power of the cells. Most cells derive
the greater part of their energy through aerobic metabolism. Because anaerobic metabolism
consists of hydrolysis of glucose into lactic acid, which undergoes further anaerobic cleavage
it does not result in the production of carbon dioxide and water but the oxidation takes place
through liberation of hydrogen. The rate of anaerobic metabolism cannot be measured
by the usual gasometric methods, but can be computed from the 'acceptor method' which
uses a dye that is highly colored when oxidized, while possessing little or no color when
reduced or hydrogenized to the so-called leuco-form.
The decoloration time of methylene blue affords an excellent indicator of the dehydrogeni-
zation power of the sperm. A highly fertile semen with an abundance of motile spermatozoa
will decolorize more rapidly than semen of poorer quality. Dr Ed. Soren sen developed a
test using special glassware and a gelation dilution fluid, and by placing the semen under
test in a water bath the decoloration time gave him an accurate estimate of its fertility. A
really fertile semen containing about one million spermatozoa per c. c, of which 50 to 60
per cent are actively motile, will decolorize his test material in ten minutes. A semen con.
taining 700,000 to 800,000 sperm cells, or which has a smaller percentage of active sperm, will
decolorize in fifteen to twenty minutes. A slightly fertile semen with a low concentration of
spermatozoa and/or many dead cells will decolorize in twenty-five to thirty minutes, while any
sample that requires more than thirty minutes to accomplish complete decoloration is con-
sidered unfertile.
FOURTH INTERNATIONAL CONGRESS FOR MICROBIOLOGY.
N EWS has been received at the office of the Indian National Committee of the Inter.
national Association of Microbiologists that the Fourth International Congress for Micro-
biology will be held at Copenhagen, Denmark, from July 20-25, 1947. The business of the
Congrees will be conducted through 9 sections. The office of the Fourth International Con-
gress is located at Kommunehospitalet, Copenhagen, Denmark. The office of the Honorary
Secretary, Indian National Committee (Dr. A. C. Ukil), is located at the All India Institute of
Hygiene and Public Health, 110, Chittaranjan Avenue, Calcutta, from whom further informa-
tion on the subject can be obtained.
For the information of those who will contribute Papers, it is stated that a summary not
exceeding 200 words should be in the hands of The General Secretary of the Congrese at
Copenhagen not later than the 1st January, 1947.