The science of synchronization of estrus and ovulation in females has made great strides. Several protocols that allow producers to precisely schedule insemination of groups of females are available for fixed-time insemination in females.

1. Protocols forProtocols for
Synchronization of EstrusSynchronization of Estrus
ByBy
Faisal A. AlshamiryFaisal A. Alshamiry
Supervision:Supervision:
Ayman SwelumAyman Swelum
Synchronization isnot asubstitutefor poor management.Synchronization isnot asubstitutefor poor management.

2.  The science of synchronization of estrus and ovulation in females hasThe science of synchronization of estrus and ovulation in females has
made great strides.made great strides.
 Several protocols that allow producers to precisely scheduleSeveral protocols that allow producers to precisely schedule
insemination of groups of females are available for fixed-timeinsemination of groups of females are available for fixed-time
insemination in females.insemination in females.
Synchronization is not a substitute forpoormanagement.Synchronization is not a substitute forpoormanagement.

3.  Developed a short list of recommended protocols to improveDeveloped a short list of recommended protocols to improve
communication about synchronization systems and improve successcommunication about synchronization systems and improve success
with the technology (Johnson et al., 2011).with the technology (Johnson et al., 2011).
 List of recommended protocols to improve communication aboutList of recommended protocols to improve communication about
synchronization systems for cattle.synchronization systems for cattle.
Synchronization is not a substitute forpoormanagement.Synchronization is not a substitute forpoormanagement.

4. The CIDRCIDR is a vaginal implant, which releases a controlled amount of progesterone
daily. One easy-to-follow program I’ve found to provide the best results includes:
Step 1Step 1, 0day0day — the cattle are run through the chute and the CIDR placed in the vagina.
They are also given a shot of one of the gonadotropin-releasing hormone (GNRH).
started allowing the CIDRs will induce cyclist on those cows. Tuck the tail neatly inside
the vulval lips.
Step 2Step 2, 7day7day — the CIDRs are removed and a prostaglandin is given at the regular
dosage.
Step 3Step 3 — The animals are given a second shot of (GNRH) when AIed, which is right on
52 to 5652 to 56 hours after the prostaglandin shot with heifers and 60 to 6660 to 66 hours with cows.
The heifers respond essentially 10 hours10 hours quicker and that is why the shorter breeding
time.
CIDR (Controlled Internal Drug Release)CIDR (Controlled Internal Drug Release)
#agrfaisal#agrfaisal

5. This diagram shows the timeline for the third A.I. synchronization protocolprotocol for cows & heifers.
00 dayday 77 dayday 1010 dayday
GNRHGNRH PGPG AIAI
GNRHGNRH
60+6hrs60+6hrsCIDRCIDR
CO-SYNCH+CIDRCO-SYNCH+CIDR
PERFORM TAI AT 60 ±
6 HOURS AFTER PG
WITH GNRH AT TAI.
#agrfaisal#agrfaisal

6. • 2×PGF.2×PGF. The 2×PGF system was one of the initial systems developed and
continues to be an effective synchronization system for females that have
attained puberty or initiated their postpartum estrous cycles.
• The primary advantage of this system is cost; however, the disadvantage
is that PGF does not initiate estrous cycles in cows that are not cycling.
• Therefore, if your cows are anestrus this system will not benefit your
program.
2×PGF.2×PGF.
#agrfaisal#agrfaisal

7. -14-14 dayday 00dayday
Heat detectHeat detect
and ALand AL
55dayday
PGFPGF PGFPGF
2×PGF.2×PGF.
#agrfaisal#agrfaisal

8. • TheThe MGA-PGFMGA-PGF system continues to be the most effective synchronization system forsystem continues to be the most effective synchronization system for
beef heifersbeef heifers, especially if cost is an issue., especially if cost is an issue.
• If producers are prepared to detect heat, success is usually high using this system.If producers are prepared to detect heat, success is usually high using this system.
• Of added importance is the opportunity to “Of added importance is the opportunity to “kick-startkick-start” or trigger heifers to start cycling” or trigger heifers to start cycling
that have failed to reach puberty yet.that have failed to reach puberty yet.
• Unfortunately, the duration for the whole treatment is approximately one month;Unfortunately, the duration for the whole treatment is approximately one month;
therefore, preparation needs to be initiated earlier than most systems.therefore, preparation needs to be initiated earlier than most systems.
• An additional disadvantage of this system is that females need to receiveAn additional disadvantage of this system is that females need to receive MGAMGA in feed;in feed;
this area of the program is often where many failures occur.this area of the program is often where many failures occur.
MGA-PGF.MGA-PGF.
#agrfaisal#agrfaisal

9. -17-17 dayday 00dayday
Heat detectHeat detect
and ALand AL
55dayday
PGFPGF
#agrfaisal
Feed MGAFeed MGA
(0.5mg/head/day)(0.5mg/head/day)
-31-31 dayday
MGA-PGF.MGA-PGF.
For producers who desire a little flexibility in a synchronization program, this is an ideal system.
Both the duration of MGA feeding and the interval from MGA to the PGF injection can be altered with little effect on response.
However, before altering any part of the protocol, be sure to understand the possible consequences.
#agrfaisal#agrfaisal

10. • Select Synch. Select Synch is one of the latest estrous synchronization systems to enter theSelect Synch. Select Synch is one of the latest estrous synchronization systems to enter the
market.market.
• As drug costs decline, this is becoming one of the most frequently used systems to synchronizeAs drug costs decline, this is becoming one of the most frequently used systems to synchronize
postpartum beef cows.postpartum beef cows.
• This system does initiate estrous cycles in postpartum cows that are not cycling.This system does initiate estrous cycles in postpartum cows that are not cycling.
• In addition, the duration of the system only requires one week from the start of synchronizationIn addition, the duration of the system only requires one week from the start of synchronization
until cows begin showing signs of estrus.until cows begin showing signs of estrus.
• For producers who utilize this system, heat checking at least three days before the PGF injectionFor producers who utilize this system, heat checking at least three days before the PGF injection
and inseminating cows then will increase the heat detection rate by up to 20%.and inseminating cows then will increase the heat detection rate by up to 20%.
• For cows that are inseminated before the PGF injection, there is no need to inject those cowsFor cows that are inseminated before the PGF injection, there is no need to inject those cows
with PGF on day 0.with PGF on day 0.
Select Synch.Select Synch.
#agrfaisal#agrfaisal

11. -7-7 dayday 00dayday
Heat detectHeat detect
and ALand AL
55dayday
PGFPGF PGFPGF
Select Synch.Select Synch.
#agrfaisal#agrfaisal

12. • CoSynch. In beef cattle operations that are fairly extensive, or would like to incorporate an AICoSynch. In beef cattle operations that are fairly extensive, or would like to incorporate an AI
• program into their operation, and feel that labor and time associated with heat detection areprogram into their operation, and feel that labor and time associated with heat detection are
limiting opportunities for AI use, then using the CoSynch protocol is a good option.limiting opportunities for AI use, then using the CoSynch protocol is a good option.
• Pregnancy rates of around 50% can be achieved in well-managed herds that use this system.Pregnancy rates of around 50% can be achieved in well-managed herds that use this system.
Unfortunately, in many areas, cost is a limiting factor, but the benefits of AI usually out-weighUnfortunately, in many areas, cost is a limiting factor, but the benefits of AI usually out-weigh
the cost factor.the cost factor.
• Keep in mind that every female that is synchronized is inseminated at a fixed time between 48Keep in mind that every female that is synchronized is inseminated at a fixed time between 48
and 54 hours.and 54 hours.
• Very few heat detection programs achieve a point at which every cow has an opportunity toVery few heat detection programs achieve a point at which every cow has an opportunity to
become pregnant.become pregnant.
• CoSynch does give every cow an opportunity to become pregnant.CoSynch does give every cow an opportunity to become pregnant.
CoSynch.CoSynch.
#agrfaisal#agrfaisal

13. -7-7 dayday 00dayday 22dayday
GnRHGnRH PGFPGF GnRHGnRH
++
AIAI
CoSynch.CoSynch.
As with the Select Synch program, several cows will come into heat before the PGF injection.
If at all possible, inseminate those females and then time inseminate the remainder of the cows at a fixed
time.
This system has not been effectively tested in beef heifers; therefore, limit the use of this system to
postpartum cows.#agrfaisal#agrfaisal

14. • Cosynch+Progestin.Cosynch+Progestin. The most effective system for synchronizing postpartum beef cowsThe most effective system for synchronizing postpartum beef cows
without heat detection is the CoSynch + Progestin system.without heat detection is the CoSynch + Progestin system.
• Preliminary data reports have indicated conception rates as high as 68% in suckled beef cows.Preliminary data reports have indicated conception rates as high as 68% in suckled beef cows.
• The general protocol is similar to CoSynch except that an implant is inserted when the firstThe general protocol is similar to CoSynch except that an implant is inserted when the first
GnRH injection is administered.GnRH injection is administered.
• The implant is removed at the time PGF is injected.The implant is removed at the time PGF is injected.
• The progestin implant prevents cows from coming into heat between GnRH & PGFThe progestin implant prevents cows from coming into heat between GnRH & PGF
administration.administration.
• A certain advantage is that cows that are anestrus before this system is used, usually will initiateA certain advantage is that cows that are anestrus before this system is used, usually will initiate
their estrous cycles shortly after removal of the implant.their estrous cycles shortly after removal of the implant.
Cosynch+Progestin.Cosynch+Progestin.
#agrfaisal#agrfaisal

15. -7-7 dayday 00dayday 22dayday
GnRHGnRH PGFPGF GnRHGnRH
++
AIAI
ProgestinProgestin
Cosynch+Progestin.Cosynch+Progestin.
For producers that would like shift their calving date to a date earlier in the year, this system is extremely effective.
Additionally, cows that have just calved with their first calf (first calf heifers) are traditionally the most difficult females for
producers to get pregnant during the breeding season. The added cost in using a system like this may pay dividends in increased
pregnancy rates.
#agrfaisal#agrfaisal

16. #agrfaisal#agrfaisal

17. Shot PGShot PG: The one-shot prostaglandin protocol is a very basic protocol in which heifers are
heat detected for 12 days.
On the 5th day of heat detection, one shot of PG is given and the heifers that respond will come
in heat in 3 - 5 days.
Heifers that have a functional CL greater than 5 days old will respond to this protocol.
00 dayday 1212dayday
PGF 2PGF 2αα
55 dayday
Heat detect and AIHeat detect and AI
Heat Detection ProtocolsHeat Detection Protocols
#agrfaisal#agrfaisal

18. CIDR + PGCIDR + PG: The CIDR is inserted intravaginally for 7days. On d 7, the CIDR is removed
and an injection of PG is given.
From day 7 to 12, heats are observed and cattle are bred 12 hours after standing heat.
The CIDR added to this protocol helps those heifers that did not have at least a 5day old CL.
It also decreases the number of days for heat detection.
00 dayday 1313dayday
PGF 2PGF 2αα
77 dayday
Heat detect and AIHeat detect and AI
CIDR
#agrfaisal#agrfaisal

19. MGA + PGMGA + PG: MGA is a feed additive progestin product.
MGA is very similar to the CIDR; the duration for treatment varies by 7days.
Heifers coming off of MGA have a first heat that is infertile.
For this reason, there is a 19 day lag is between MGA and PG shot.
MGA is not labeled for use in cows.
00 dayday 3939dayday
PGF 2PGF 2αα
3333dayday
Heat detect and AIHeat detect and AI
Treat. 19 DMGA
#agrfaisal#agrfaisal

20. Heat Detect and TAI Combination Protocols:
CO-Synch + CIDR: This protocol uses several different pharmacological
products to synchronize ovulation.
Cost is higher, but labor to detect estrus is reduced.
00 dayday 1313dayday
PGF 2PGF 2αα
77 dayday
Heat detect and AIHeat detect and AI
GnRHGnRH
GnRH +GnRH +
TAITAI
CIDR
#agrfaisal#agrfaisal

21. MGA – PGMGA – PG: For operations that have ample bunk space to feed heifers and
make sure each heifer is getting an effective dose of MGA.
Same 19 d lag as MGA + PG heat detect protocol due to the infertile first cycle,
but shorter heat detect and AI window.
Breed heifers and give GnRH injection 72 hours after PG injection.
1414 dayday 3636dayday
PGF 2PGF 2αα
3333dayday
Heat detect and AIHeat detect and AI
GnRHGnRH
TAITAI
00 dayday
Treat. 19 dayMGA
#agrfaisal#agrfaisal

22. 00 dayday 1313dayday
PGF 2PGF 2αα
77 daydayTreatment dayTreatment day
GnRHGnRH
GnRH +GnRH +
TAITAI
54 ± 2 hr54 ± 2 hr
CIDR
Fixed-Time AI ProtocolsFixed-Time AI Protocols:
Select Synch + CIDR and TAI: Uses heat detection for 3 days to breed any
heifers that may come in early and then TAI the remainder 72 -84 hours after
CIDR removal and PG injection.
#agrfaisal#agrfaisal

23. 1414 dayday 3636dayday
PGF 2PGF 2αα
3333dayday
GnRHGnRH
TAITAI
00 dayday
Treat. 19 dayMGA
Fixed-Time AI ProtocolsFixed-Time AI Protocols:
MGA – PG + TAI: For operations that have ample bunk space to
feed heifers and make sure each heifer is getting an effective dose of
MGA. This protocol allows for 3 days of heat detection and AI,
followed by a final TAI 72 -84 hours after PG injection.
#agrfaisal#agrfaisal

24. 1414 dayday 3333dayday
PGF 2PGF 2αα
3030dayday
GnRH+GnRH+
TAITAI
00 dayday
66 ± 2 hr66 ± 2 hr
Treat. 16 dayCIDR
Fixed-Time AI ProtocolsFixed-Time AI Protocols:
14-day CIDR – PG14-day CIDR – PG: This protocol is very similar to the MGA
protocol listed above.
However, duration between CIDR removal and PG injection is
shorter due to faster clearance of progestin from a CIDR.
For operations that do not have adequate bunk space to feed and
monitor MGA intake this protocol is a good option.
#agrfaisal#agrfaisal

25. #agrfaisal#agrfaisal

26. Inject
PGF Heat detect and AI
Day 11
Reinject
PGF
Heat detect and AI
Day 22 Day 55 Day 88 Day 99 Day 1212
Weekly Prostaglandin ProgramWeekly Prostaglandin Program
#agrfaisal#agrfaisal

27. Inject
PGF Heat detect and AI
Day 11
Reinject
PGF Heat detect and AI
Day 22 Day 55 Day 1515 Day 1616 Day 1919
- Cow not inseminated since first PGF injection -
Double Injection Prostaglandin ProgramDouble Injection Prostaglandin Program
#agrfaisal#agrfaisal

28. Stop
feeding
Day 11
GnRH
Day 1414 Day 2626 Day 3333 Day 3434
Inject
PGF
MGA(0.5mg/head/day
)
Sub fertile
heat
PGFα2 Heat +
AI
MGA SynchMGA Synch
#agrfaisal#agrfaisal

29. PGF
Day 11
PGF
Day 77 Day 1818 Day 1919 Day 2222
MGA(0.5mg/head/day
)
GnRH
Heat +
AI
Day 1111
7-11 Synch7-11 Synch
#agrfaisal#agrfaisal

30. PGF
Injection
Day 00
Remove CIDR
Day 66 Day 77 Day 7-127-12
Heat DETECT + AIInsert
CIDR
CIDR SynchCIDR Synch
#agrfaisal#agrfaisal

31. GnRH
Day 11 Day 1515 Day 2424 Day 2626
PGF
Day 2222
Setup
PGF
Heat Detect And AI Or Timed
Insemination 72-80 Hours
Modified Targeted BreedingModified Targeted Breeding
#agrfaisal#agrfaisal

32. PGF
Injection
Day 11 Day 88
GnRH
Injection
Day 1010
GnRH
Injection
AI (8-18) hours later
OVSynch ProgramOVSynch Program
#agrfaisal#agrfaisal

33. Injection
GnRH
Day 11 Day 99
PGF
Reinject
Day 1616
Insert
PGF
Injection
GnRH
AI 16 h later
Day 33 Day 1818
G6G SynchG6G Synch
#agrfaisal#agrfaisal

34. #agrfaisal#agrfaisal

36. UtilisationUtilisation
ProtocolProtocol

37. EstrusEstrus
synchronizationsynchronization
withwith
ProstaglandinProstaglandin
(PGF2 )α(PGF2 )α

38. EstrusEstrus
synchronizationsynchronization
with Ovsynchwith Ovsynch
Protocol GPGProtocol GPG
7days7days