March, 1954]               S. S. PRABHU AND P. BHATTACHARYA            37

          PHYSIOLOGICAL STATE OF THE 'TEASER' COW

Ordinarily bulls will take notice only of cows 'on heat', such cows alone will
'stand' to the bull. According to Sarthou-Montengou [1950], the motivating
factor arousing the sex desire in the bull that leads him to the cow 'on heat' is
the smell of oestrogenic substances present in the secretions thrown out by the
cow ' on heat'. When a cow is trained to stand to the bull and the bull trained to
mount a cow which is not in heat, as in artificial insemination collection practice, a
condition foreign to both the cow and the bull is introduced; the probable effect
of which on the continued sex-drive and semen production of the bull remaining
unknown. Results obtained with collections taken on teaser cows 'on heat' appear
to suggest that the sex-urge of the bull is heightened by the physiological condition
of the teaser cow. For example, in a series of exhaustion tests conducted on ten
buffalo bulls there was a prima facie case for drawing such a conclusion. The results
are discussed in some detail in Table I as these are the first data of the kind in buffa-
loes.

                                            TABLE I

              Results of exhaustion tests conducted on buffalo bulls