Vie CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., FARIS, 1968, VOL. Il

FERTILIZING ABILITY AND BIOLOGICAL ASPECTS OF SPERM STORAGE IN VITRO

 

G. W. Salisbury
Department of Dairy Science
University of Illinois, Urbana, Il1linois, U.S.A.

Members of the Congress, Ladies and Gentlemen:

| have been asked to discuss for this Congress a basic and prac-
tical problem which confronts everyone employing the techniques of
artificial insemination and to present, insofar as the evidence per-
mits, the scientific basis for the answer. How long will the sperma-
tozoa remain alive and fertile? Fertility of spermatozoa as discuss-
ed here refers not only to their capacity to fertilize ova but to
contribute to the zygote all the genetic components required for suc-
cessful embryogenesis and for proper fetal development.

i would be something less than candid if | did not say in de-
scribing our findings at the University of |1linois that the path to
a solution and an understanding of the problem was not as clear in
the beginning as it appears now. Also, it should be understood that
every artificial insemination operation or the director of any care-
fully planned experiment can determine the time limits of male gamete
fertility better for their own conditions and economic situations
than can be predicted from the experiments | shall describe.

Our work in cattle insemination at ll1linois has been conducted
under conditions peculiar to us in the American Midwest for cattle
kept between the 38th and 40th parallel of latitude under humid con-
ditions approaching a high of 38°C or more in summer days and winter
cold sometimes as low as -30°C or lower. The time limits of economic
fertility we have found are for our conditions! Others must define
their own conditions and determine their own time limits. Neverthe-
less, it is our conviction that the trends we have shown and our dis-
coveries of the cause of those trends are generalizations to be found
in varying degrees everywhere.

Our experiments on fertility have consisted of field trials in
cooperation with a number of American artificial insemination centers
and laboratory experiments using rabbits and frogs.

The data from A.l. have been obtained both from planned investi-
gations in which the experiment was designed and carried out at an

A.l. center from which the extended semen was shipped for use, and
from statistical surveys of already obtained operational evidence.

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