Vle CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. II

APPLICATION OF 2OSIN FOR DIFFERENTIAL STAINING OF BUFFALO
SPERMATOZOA
Part I. Efficiency of fluorescein derivatives for differential
staining of buffalo spermatozoa.
NOUR EL~DIN A. ALY, OMAR, M.A., YOUNES, A.A., ABBOUD, M.Y.
Animal Science Research Institute, U.A.R., Dokki.

The routine methods for semen evaluation, used in the practice
of artificial inseminastion should be studied and assessed for their
suitability as criterions for judging buffalo semen. This will enable
the modification or the establishment of new standards for these tests.

One of the criterions for judging semen quality is the sperm mo-
tility. This motility test should always be supported by another con-
firmatory test using differential stains for determination of live
sperm percentage.

Due to the great controversy about the stains used, the present
investigation was carried out to determine the efficiency of fluores-

cein derivatives for differential staining of buffalo spermatozoa.

Experimental. Different concentrations of eosin yellowish and of
eosin bluish (I-IO0%) were prepared. The difference between concen-
trations was I%. The solvent used was normal saline. Semen used was
collected from 2 buffalo bulls. Motility ratings were made initially
on nondiluted buffalo semen. 600 smears from 30 ejaculates were in-
vestigated. The correlation between concentration of the stain and

percentage of live sperm was also determined.

Results. l.Average motility rating was 68.33 - 1.00%.

2.The highest percentage of unstained sperm was 67.74:0.40%,obtained
by using a solution of 2% eosin yellowish.

3.Stain solutions of 1% and 3% eosin yellowish led to about equal
results (58.00%0.41% and 58.47%0.25% of live cells respectively).
4.The lowest percentage of live sperm (26.52%0.36;!) was obtained

by using 10% eosin yellowish.

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