Reproductive Physiology of Beef and Cattle

Suporn KatawatinDepartment of Animal Science

Khon Kaen University

Reproduction is one of the most

important consideration determining the

profit of cattle production

CONTROL GENITAL

DISEASE

PREGNANCY

DIAGNOSISIMPROVE AI TECHNIQUE

USE GOOD QUALITY SEMENBREED COWS IN STANDING

HEAT

DAYS OPEN

(85 days)

MANAGEMENT

ARTIFICIAL

INSEMINATION

FEMALE

FERTILITY

HERD HEALTH

REDUCE AGE AT 1ST CALVING

INCREASE % COWS CYCLINGTREAT PROBLEM COWS

RECORD

NUTRITION

ESTROUS DETECTION

Good reproduction is …

to show regular cyclic breeding activity

Reproductive Physiology

Male and Female Reproductive Anatomy

Puberty : age or body weight

Sexual maturity

Estrous Cycle

Mating or Breeding

Calving

Lactation

Recycling

Female Reproductive Characteristics of Cattle and Buffalo

Parameters Cattle Buffalo

Age at puberty (mth)

-15 10(24)

-21 15(3 6 )

Estrous cycle Length (d) Estrus (h)

-21 14(29)

-18 12(30)

-21 18(22)

-2117

24)

Ovulation Type Time from onset (h)

Spontaneous -30 18(48)

Spontaneous -32 18(45)

Parameter Cattle Buffalo

Life span of CL (d) 16 16

Fertilizable life of ova (h)

(20 – 24) ??

Entry of ova into uterus (h after ovulation)

90 6(-496)

??

Gestation length (d) -2802782(93)

315 (-305

330

Female Reproductive Characteristics of Cattle and Buffalo

Parameter Cattle BuffaloAge at 1st calving (months)

30 (-24

36)

42 (-36

5 6 )Postpartum interval (days) Uterine involution First ovulation

45 (-32

50) 30 (-10

110

)

35 (-16

60) 75 (-35

180

)Calving interval (months)

13 (-12

14)

18 (-15

21)

Female Reproductive Characteristics of Cattle and Buffalo

Controlled reproduction

in cattle

Breeding cattle at younger ages

Control estrus

Pregnancy testing

Control calving

Control postpartum interval

Suppression of estrus

Embryo transfer & in vitro

fertilization

Induction of twin births

Areas of controlled reproduction in female cattle

Heat Detectionor Estrous Detection

Estrous behavior

Before heat (6-10 h)

Smells other cows

Attempts to ride other cows

Vulva moist, red slightly swollen

Stand to be ridden

Bawls frequently

Nervous & excitable

Off feed and milk

Vulva moist and red

Clear mucous discharge

Eye pupil dilated

Standing heat (18 h)

After heat (10 h)

Will not stand

Clear mucous discharge from vulva

Before heat (6-10 h)

Hours from the start of estrus

Hours 0 6 9 18 24 28

Egg released

Life of egg (6-10 h)

Standing heat (18 h)

After heat (10 h)

Estrus in cow and associated featured

Techniques used in estrous

detection

Use of closed circuit television

Tail-painting & use of chalk

Chin-ball devices

Use of teaser

animalsVaginal probes

Heat-mount detectors

Progesterone tests

Cow activity changes

Approaches to estrus detection in the cow

Hormonal Pattern During

Estrous Cycle in Cow

Hormones Used for Induction of Estrus and Ovulation

Type of hormones Method Biologic Activity

Gonadotropins eCG or PMSG Single injection Mimics FSH and

stimulates follicular growth; long half-life

FSH Single/multiple injections

Stimulates follicular growth; short half-life

hCG Single injection Mimics LH and induce ovulation

Type of hormones Method Biologic Activity

Gonadotropin Releasing Hormone Agonist GnRH-buselerin

Single injection

Induces release of LH and FSH from the anterior pituitary gland; recruitment and selection of new dominant follicle

Hormones Used for Induction of Estrus and Ovulation

Type of hormones

Method Biologic Activity

Progestogens

Progesterone Multiple injections

Inhibits ovulation by suppressing LH; mimics action of CL

Synthetic progestogens

Oral, subcutaneous implant, intravaginal device

Inhibits ovulation by suppressing LH; mimics action of CL

Hormones Used for Induction of Estrus and Ovulation

Hormones Used for Induction of Estrus and Ovulation

Type of hormones Method of Administration

Biologic Activity

Estrogens Estradiol conjugates

Injection, implant

Induce premature regression of CL, and enhances response to progestrogens

Prostaglandins PGF2 or synthetic analogs

Single intramuscular injection

Induces regression of CL during responsive phases

Protocols for Inducing Estrus and Ovulation in Acyclic Cattle and Buffalo

Treatment End of Treatme

nt to Estrus

Prepubertal or postpartum suckled cows

Estrogen on day 1 followed by 7 -12 days of progesterogen, eCG given on last day (optional)

Within 5 days

Postpartum milked cows

GnRH on day 14 postpartumGnRH (day 0) and PGF (day 6)

1 day

2-4 days

Techniques for Synchronizing Estrus in Cyclic Cattle

Method Treatment Regimen

End of treatment to estrus

PGF Two injections (11-12 days apart)

3-5 days: AIDE/TAI

GnRH + PGF

Inject GnRH (day 0), PGF (day 6)

2-4 days: TAI

GnRH + PGF + GnRH

Inject GnRH (day 0), PGF (day 7), GnRH (day 8 or 9)

2-4 days: TAI

Techniques for Synchronizing Estrus in Cyclic Cattle.

Method Treatment Regimen

End of treatme

nt to estrus

Progestogen + estrogen

Estrogen injection (day 1), CIDR (day 1-9X

3-5 days : AIDE/TAI

Progestogen +PGF

Progestogen (days1-7), PGF (day 6)

2-3 days: AIDE/TAI

GnRH (100ug)

PGF2

(35mg)

Ovulate follicle Start new follicle

wave

GnRH (100ug)

Breed (cows)

Regress corpora lutea

Ovulate follicle

7 days 48 h 24 h

Timing and purpose of hormones to synchronize ovulation in lactating dairy cow (Pursley et al.,

1995)

OVSync

Measure Reproductive Efficiency

Trait DefinitionFirst calving

Age (months)

Days open Days calving to conception

Calving interval (days)

Days between successive

calving Total cows

First service conception rate (%)

No. pregnant 1st service X 100No. bred 1st

service

Trait DefinitionServices per conception

No. of services in all cows

Total conceptionsPregnancy rate (%)

No. of cows pregnant X 100

Total cows in herdCalving rate (%)

No. of calves born X 100

Total cows in herdNet calf crop (%)

Total calves weaned X 100

Total cows in herd

Measure Reproductive Efficiency

Book Suggestion

Hafez, E.S.E. and B. Hafez. 2000. Reproduction in Farm Animals. 7th ed. Lippincott Williams & Wilkins, New York.

Gordon, I. 1996. Controlled Reproduction in Cattle & Buffaloes. CAB International.

Bearden, H.J. and J.W. Fuquay. 1997. Applied Animal Reproduction 4th ed. Prentice Hall.

Approximate Values for Selected Reproductive Events in Female Domesticated Mammals

 Species

 Length of cycle (days)

 Duration of estrus (hours)

 Approximate time of ovulation

 Normal breeding season

 Cow Mean=20.5  Range 17 - 23

Mean < 10  Range 1 - 24

 30 h after beginning of estrus 

 All year

 Buffalo

Mean=21  Range 18 - 22

Mean < 15  Range 4 - 24

 32 h after beginning of estrus

 All year 

 Mare Mean=21  Range 12 - 35

Mean=120  Range 24 - 240

 Near end of estrus  Spring & summer

 Ewe Mean=16  Range 12 - 19

Mean=30  Range 20 -48

 26 h after beginning of estrus 

 Fall (variable with breed)

 Doe Mean=20  Range 16 - 22

Mean=40  Range 24 - 72

 On 2nd day of estrus  Fall

 Sow Mean=20  Range 16 - 22

Mean=48  Range 24 - 90

 36 h after beginning of estrus 

 All year