2. Study Of Estrus
Cycle In Buffaloes
Dr. Muhammad Awais

3. Estrus cycle
 Cyclic or recurrent set of physiological and
behavioral changes that takes place from
onset of one estrus period until onset of the
next estrus is called estrus cycle.

4.  The age of puberty in buffalo is 36 to
42 months in Pakistan.
 The estrus cycle length is 21 days with
a heat duration of 12-24 hour.
 The ideal buffalo produces a calf every
13 to 14 months.

5. Poor heat sign
 Silent heat in the buffalo is one of the most
important unsolved impediments to efficient
breeding.
 It occurs in the hot seasons.
 A combination of estrus detection methods
may be necessary for identification of
animals in heat.

6. ovary

9. Phases of Estrus Cycle
 Estrogenic or Follicular Phase:
Proestrus + Estrus
 Progestegenic or Luteal Phase:
Metestrus + Diestrus

12. Phases...
Phase 1.
Pro-estrus (2- 3 days)
 Just before estrus
 Growth of follicles under the influence of FSH
 Follicle gradually produces estrogen
 Increasing concentration of estrogen causes:
Vascularization
Swelling of vulva
Production of mucus

13. Buff ovary… Pro estrus
 Decrease CL size and color (decreased
vascularity) of the regressing CL
 The newly developed dominant
follicle

14. Phase II.
Estrus (1 days)
 Heat period or period of sexual desire
 The female shows sexual receptivity
 follicles under go maturation.
 FSH is at peak and LH starts to secrete
 Estrogen level is high and Regression of CL of previous
cycle is complete
 Progesterone level becomes very low.
 Duration varies from 6- 30 hrs (majority fall in the range
of 17-21hrs)
 varies from species to species and individual

15. Phase - II
Characterized by:
 Primary sign
 Stands immobile when mounted

16. Signs of estrus in buffaloes
Stands to be mounted

17. Phase- II Secondary Signs
Buffaloes has silent heat, mostly sign Show during Night time.
Behavioral sign
 Bellowing
 Increased activity
 Charging
 Licking
 Circling
 Chin resting
 Mounting
Physical signs
Red vulva
Swollen vulva
Clear mucus discharge from
vulva

18. Signs of estrus in buffaloes

19. Signs of estrus in buffaloes
Transparent mucous discharge from vulva

20. Signs of estrus in buffaloes
Swollen vulva

21. Phase - II Miscililnous signs
 Decreased appetite
 Decreased milk production
 Frequent urination

22. Phase 3.
Met estrus. 2- 3 days
 Ovulation occurs
 CL development starts
 Estrogen level falls and progesterone by luteal cells
increases with the development of CL.
 The CL is formed by Hypertrophy and hyperplasia
of granulosa cells
 and partly by theca interna cells
 which are now called luteal cells.

23. Metestrus...Ovulation
 At birth all female calves born with primordial
follicles
 They never increase but only decreased during life of
the animal
 As ovulation approaches follicles grow and mature

24. Ovul...
During Growth and maturation the develops as:
1. Primordial follicles
2. Growing follicles
3. Vesicular follicles

25. Ovul...
 Under the influence of FSH and LH follicles
grow and mature
 Development start in fetal life, remains continue
in young life before and after puberty and even in
pregnancy
 Follicular growth and development culminating
in mature GF and ovulation occurs only in non
pregnant animals after puberty during
reproductive cycle

26. Ovul...
 Circumscribed a vascular area appears on the apex of
the ovary that projects above the ovary
 This breaks and follicular contents ooze out from
follicle
 This is because of LH that releases histamine causing
ovarian hyperemia
 Due to ovarian hyperemia proteolytic enzymes
(collagenase) inters into the follicular fluid
 This enzymes weaken follicular wall
 Pressure due to increasing follicular fluid and weaken
wall both causing ovulation

27. Phase - III
 Development of Corpus luteum
 Cessation of heat signs
 Vulva wrinkled
 Flow of mucus diminished

28. Phase IV
Di-estrus 11-15 days
 CL fully functional
 uterine glandular system develops for
nourishment of embryo
 If pregnancy does not occur CL start
regressing
 Follicles start to grow
 phase ended with the start of an other
proestrus
 Fully developed corpus luteum (CL)

30. Factors affecting the
occurrence of estrus in buffalos
 Nutrition state
 Seasonal influence
 Age
 Work
 Transportation
 Diseases
 Pathology of Reproductive system