June, 1952] D. P. MUKHERJEE AND P. BHATTACHARYA 83
It is apparent from the table that the ' reaction-time' of bulls did not show any
relationship with the quality of semen produced by them. The quality of semen
of bulls under the same bar, which did not show significant variation in their average
''reaction-time' varied considerably. For instance, the semen quality (as judged
by initial motility, sperm concentration and total number of spermatozoa) of bull
248, whose ' reaction-time ' did not vary significantly from bulls 240 and 194, was
significantly inferior to that of those two bulls. Bulls 195 and 200 did not vary
in their ' reaction-time' but there was a significant variation in all their semen
attributes except pH, motility and volume of semen ; bull 200 was inferior to bull
195. Similarly, the semen of bull 187 which did not significantly vary from bull
194 as regards ' reaction-time ', was inferior to this bull. It seems, therefore, that
in bulls the ' reaction-time ' which is an indication of sex-vigour is independent of
sperm production and the quality of semen.
Regarding volume of semen, bull 187 gave the largest quantity and bull 248
the smallest. Bull 195 was inferior to bull 240. The rest of the bulls did not vary
among themselves. Although the volume of semen from bull 187 was much higher
than from the rest, the initial motility and sperm concentration in this bull were
the lowest. It seems that the amount of the accessory glands secretions in this
bull was much more than in others, presumably it was due to this particular animal
being three years older than the rest.
Initial motility of bull 248 was significantly higher than bull 187 but lower than
the remaining bulls. Bull 194 was inferior to bull 195. The variation among bulls
194, 200 and 240 was not significant.
As regards pH of semen there were two distinct groups. Group A included
bulls 195, 240 and 200 and Group B included 187, 194 and 248. The semen quality
(as judged by sperm concentration, initial motility and total number of sperma-
tozoa) of all the animals in Group A was decidedly superior to that of bulls 187
and 248 of Group B. The reason why the semen of bull 194 showed higher pH
inspite of higher concentration and total number of spermatozoa may be found in
the fact that during December 1946 to April 1947 the animal suffered from, inflamma-
tion of the seminal vesicles. Due to this inflammation the semen samples during
this period were found to be very alkaline and contained leucocytes ; furthermore
the initial motility of spermatozoa was also low during this period. It appears,
therefore, that in animals showing the normal range of pH of semen, those with
comparatively higher pH value are poorer in sperm concentration, total number
of spermatozoa and initial motility.
Sperm concentration in bull 200 was significantly higher than in bulls 187 and
248. Bull 240 was inferior to bull 194. It will be seen that there was a direct
relationship between the sperm concentration and initial motility of spermatozoa.
Sperm concentration and initial motility were observed to be lower in bull 187.
Bull 200 which was decidedly better than bulls 187 and 248 for sperm concentra-
tion gave samples with higher initial motility. Between bulls 240 and 195 there
was neither significant variation in sperm concentration nor in initial motility.