This document discusses methods for estrous synchronization in cattle and sheep. Estrous synchronization aims to group females for calving, shorten breeding seasons, and reduce estrus detection. Key methods include using progesterone-releasing implants, pessaries, or feeding melengestrol acetate to extend the luteal phase. Prostaglandins are then used to induce luteolysis and estrus. Common synchronization protocols for cattle include Ovsynch, which uses GnRH and PGF2α, and CIDR-based protocols. Vaginal sponges and CIDR implants of varying durations can also be used in sheep and goats.

1. Estrous Synchronization
by
Armia Naguib

2. Why synchronize?
 Group females for parturition (calving
interval)
 Shorten breeding season
 Reduce estrus detection

3. Extend of luteal phase:
progesterone
Shorten of luteal phase:
Prostaglandins PGF2
Synchronization methods

4. progesterone
• Method of application:
1. Injection: Time Consuming
2. Implant : Place in ear
3. Feed: Mix in ration
4. Pessary :Place in Vagina
Vaginal spongy
 CIDR
 PRID

5. Implant in cattle

6. Implant in sheep

7. Feed MGA
Short term

8. Feed MGA
Long term

9. Pessary
Vaginal spongy( used for sheep)
Short term: 9 days
Long term: 19 days
 CIDR
For cow: 7 days
 For sheep,goat: 12-16 days
 PRID

10. Vaginal sponge Short term
Vaginal
Sponge
At 1day
At 7 day
PMSG
At 9 day remove of
sponge then at
day10-13 make
estrus detection&
Breed

11. Vaginal sponge long term
Vaginal
Sponge
At 1day
At day 17
PMSG
At day 19 remove
of sponge then at
day27-30 make
estrus detection&
Breed

12. CIDR For cow: 7 days

13. CIDR For sheep,goat: 12-16 days

14. Prostaglandins PGF2
• 3 Protocols
One Shot ( injection)
Two Shot ( injection
 One injection with heat detection

16. GnRH synchronization protocols

17. Updated: 5/30/2014
Ovsynch (GPG)
7 Days 36 - 48 hours
GnRH PGF2
8 - 18 hours
Timed AI
GnRH

18. • Modified Target breeding (PGP)
PGF2
14Days
GnRH
6-7 days
PGF2
2-3 day
Timed AI

19. Pre-Synch Protocol(PPGPG)
begin at day 37 postpartum
Synchronization at
day 51
Cows are on Days 5-9 of
cycle. New Follicular wave
started (inject at day 63)
Synchronized follicular wave.
Regression of CL (inject at
day 70)
Clean Up Shot