Study Of Estrus Cycle In Buffaloes

Dr. Muhammad Awais

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.

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.

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.

ovary

Phases of Estrus Cycle

Estrogenic or Follicular Phase:Proestrus + Estrus

Progestegenic or Luteal Phase:

Metestrus + Diestrus

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:

VascularizationSwelling of vulvaProduction of mucus

Buff ovary… Pro estrus

Decrease CL size and color (decreased vascularity) of the regressing CL

The newly developed dominant follicle

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

Phase - II

Characterized by: Primary sign Stands immobile when mounted

Signs of estrus in buffaloes Stands to be mounted

Phase- II Secondary SignsBuffaloes has silent heat, mostly sign Show during Night time.

Behavioral sign Bellowing Increased activity Charging Licking Circling Chin resting Mounting

Physical signsRed vulva

Swollen vulva

Clear mucus discharge from vulva

Signs of estrus in buffaloes

Signs of estrus in buffaloes Transparent mucous discharge from vulva

Signs of estrus in buffaloes Swollen vulva

Phase - II Miscililnous signs

Decreased appetite Decreased milk production Frequent urination

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.

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

Ovul...During Growth and maturation the develops as:

1. Primordial follicles2. Growing follicles3. Vesicular follicles

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

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

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

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)

Factors affecting the occurrence of estrus in buffalos

Nutrition state Seasonal influence Age Work Transportation Diseases Pathology of Reproductive system