2.3. Detection of estrus in buffalo cows
The phases of the estrous cycle were carefully determined
for three naturally occurring consecutive cycles and
confirmed by examination of genitalia per rectum. The
stages of the estrous cycle were identified according to
several criteria, including vaginal swelling, frequent urination,
bellowing of females, and male flehmen behavior.
The onset of estrus was checked twice daily (07:00 and
17:00 hours) by teaser bull parading. The time when any
animal stood for mounting by the teaser bull was considered
as the time of onset of estrus and as evidence that the
animal was in standing heat. Pregnancy was confirmed by
transrectal palpation by assessing the morphological
changes in the internal reproductive organs. The length of
normal estrous cycle based on onset of behavioral estrus
ranged from 18 to 22 days.