Pm. Zavos et al., MEASUREMENT OF THE SPERM MOTILITY INDEX VIA THE SPERM QUALITY ANALYZER AND ITS RELATIONSHIP TO OTHER QUALITATIVE SPERM PARAMETERS, Theriogenology, 46(3), 1996, pp. 421-427
Sperm parameters such as the concentration and percentage of motile sp
ermatozoa are commonly used to assess semen quality. The sperm quality
analyzer (SQA) is a device that detects variations in the optical den
sity of motile spermatozoa, providing a sperm motility index (SMT) tha
t is based on various sperm parameters including the concentration, mo
rphology and acrosomal status of motile spermatozoa. The relationship
between SMI values of frozen-thawed bovine spermatozoa undergoing swel
ling in a hypoosmotic medium (100 mOsm/L) and other sperm parameters w
ere evaluated. Frozen semen specimens from 3 bulls were thawed and was
hed with Ham's F-10 supplemented with 3% BSA and split into 3 (0.2 mL)
aliquots. The aliquots were diluted with 1.0 mL of Ham's F-10 (Aliquo
t 1), isotonic sodium citrate (Aliquot 2), and hypotonic sodium citrat
e (Aliquot 3). The osmotic pressure of the media used for dilution of
Aliquots 1 and 2 was 300 mOsm/L, while that for Aliquot 3 was 100 mOsm
/L. Following dilution, the aliquots were incubated for 30 min and man
ually assessed at 5-min intervals for the percentage and grade of moti
lity (Grades 0 to 4) as well as for the percentage of swollen spermato
zoa. Sperm samples were simultaneously evaluated by SQA to obtain the
SMI values at the same 5-min intervals during the 30-min incubation. S
ignificant correlations were observed between SMI values and other spe
rm parameters in Aliquot 3 (P<0.05). The results indicated that the SM
I values obtained from frozen-thawed bovine spermatozoa exposed to a 1
00 mOsm/L diluent, which causes optimal swelling of spermatozoa, are h
ighly correlated to other sperm parameters. The SQA unit, as applied i
n this study, can be used for rapid and reliable screening of sperm sa
mples.