NEW OPPORTUNITIES TO SYNCHRONIZE ESTRUS AND FACILITATE FIXED-TIME AI

1
NEW OPPORTUNITIES TO SYNCHRONIZE ESTRUS AND
FACILITATE FIXED-TIME AI
DJ Patterson, MF Smith, and DJ Schafer

• Division of Animal Sciences
• University of Missouri-Columbia
• July 6, 2005

2
The current status of reproductive technology in
the U.S. beef cattle industry
3
Reproductive Technologies Available or on the
Horizon

• Estrus synchronization and AI
• Ultrasonography
• Sexed semen
• Embryo transfer
• In vitro production of embryos
• Transgenics (pharming)
• Cloning
• Male fertility

4
The U.S. Beef Herd

• 69 of cow-calf enterprises are secondary income
  sources
• 50 of producers report an established breeding
  season of specific duration
• 34 of beef herds are routinely pregnancy checked
• 10 of beef cattle enterprises utilize AI

5
Whats happening in adoption of technology in the
beef industry on a global basis?
6
In the U.S. ...
Total Domestic Sales of Beef Semen
Hough,, 2002
7
Comparison of AI Use In Beef Cattle (U.S. vs.
Brazil)
8
Import and Domestic Beef Semen Sales(units sold)
1993 1,117,798
2003 1,025,116
1993 1,874,996
2003 4,896,204
161 change
-8 change
From NAAB, 2003 ASBIA, 2003
9

• Unless efforts are taken to implement change in
  the U.S. beef cattle industry, the products of
  our research and technology may be exported to
  more competitive international markets . . . . .
  . (Patterson et al., 2000).

10
Why are we here?
11
Artificial insemination and estrus
synchronization are generally regarded as the
most important and applicable of all available
biotechnologies to the beef cattle industry
(Seidel, 1995).
12
(No Transcript)
13

• Improvements in methods to synchronize estrus
  create the opportunity to significantly expand
  the use of AI in the U.S. cowherd .

14
A unique point in time for the U.S. beef
industry

• Availability of tools and understanding of
  methods to control the estrous cycle in cattle
• A changing market structure that recognizes and
  rewards quality

15
A unique point in time

• If we dont impact use of AI among beef producers
  in the U.S. in the near future, will we ever?

16

• The challenge of transferring technology (estrus
  synchronization and AI) to the private sector
  exceeds the task of research and development of
  still newer technologies.

17
Collectively

• Adopt common terminology regarding the various
  estrus synchronization protocols
• Identify and agree upon short lists of protocols
• heifers and cows
• heat detect and AI vs fixed-time AI
• Work to overcome the attitude of What will this
  cost me? .to Im willing to make an
  investment in my herd

18
Effective Estrus Synchronization Programs for
Beef Cattle

• Facilitate AI ET
• Reduce time required to detect estrus
• Cycling females conceive earlier in the breeding
  period
• Induce cyclicity in peripubertal heifers and
  anestrous postpartum cows

19
Objective Development of highly effective
economical estrus synchronization programs

• Peripubertal heifers
• Postpartum cows
• Anestrus and estrous cycling
• Excellent pregnancy rates

20
Products Currently Available

• Prostglandin
• Lutalyse, Estrumate, ProstaMate, In Synch,
  EstroPlan
• GnRH
• Cystorelin, Factrel, Fertagyl, OvaCyst
• Progestins
• MGA
• CIDR

21
What We Know About MGA . . .
22
(No Transcript)
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What We Know About MGA . . .

• Induces puberty in beef heifers
  (Imwalle et al., 1998)
• Prevents expression of behavioral estrus
  (Zimbelman and Smith, 1966 Imwalle et
  al., 2002)
• Blocks the preovulatory surge of LH
  (Imwalle et al., 2002)
• Blocks ovulation
  (Zimbelman and Smith, 1966
  Imwalle et al., 2002)

24
HEIFERS
25
Reproductive Tract Scores (RTS)
Adapted from Anderson et al., 1991
26
Reproductive Tract Scores (RTS) Summary
Pelvic Width (cm) 10.9a 11.2a 11.4b 11.7c 11.7c
Pelvic Height (cm) 13.9a 14.1a 14.5b 14.7c 14.7c
Pelvic Area (cm2) 152a 158a 166b 172c 172c
Estrous Response () 54a 66b 76c 83d 86d
Weight (lb) 594a 620b 697c 733d 755d
RTS 1 2 3 4 5
n 61 278 1103 494 728
a, b, c, d Numbers with different superscripts
within a column differ (P lt 0.05)
Adapted from Patterson and Bullock, 1995
27
Comparison of reproductive performance in herds
using natural service or synchronization and AI
on replacement heifers by RTS
Exposed Exposed 21-d PR2 21-d PR2 42-d PR3 42-d PR3 TPR4 TPR4
RTS1 NS5 (n) SAI6 (n) NS () SAI () NS () SAI () NS () SAI ()
1 8 55 38a 42a 63c 55c 63e 60e
2 108 661 31a 52b 54c 68d 75e 82e
3 336 3320 41a 58b 65c 74d 82e 87f
4 322 3629 48a 62b 72c 77d 91e 87f
5 242 2835 50a 64b 74c 80d 88e 88e
TOT 1016 10500 44a 61b 68c 73d 85e 87e
a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005 a,b Means within rows for 21-d PR with different superscripts differ (P lt .05) c,d Means within rows for 42-d PR with different superscripts differ (P lt .05) e,f Means Within rows for TPR with different superscripts differ (P lt .05) From Randle and Patterson, 2005
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Synchronized
estrus
Estrus
PG
MGA (14 days)
1 14 16 20 31 33
36
Treatment days
Brown et al., 1988
29
MGA-PG14-19 d

• Improved estrous response
• More heifers in heat
• Similar fertility
• No change in conception or pregnancy rate
• Improved synchrony
• More heifers in heat in a shorter time

(Deutscher et al., 2000 Lamb et al., 2000)
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MGA-PG
PG
MGA (14 days)
1


14

33
MGA Select



Wood et al., 2001
31
Wood et al., 2001
32
Wood et al., 2001
33
When to Add GnRH to an MGA-PG Protocol for
Heifers

• Consideration of . . . .
• Age
• Weight
• Reproductive tract score (RTS)
• Pubertal status

Wood et al., 2000 Kojima et al., 2001
34
How do MGA- and CIDR-based protocols compare in
heifers?
35
Experimental Protocols
MGA Select
PG
GnRH
MGA (14 days)
.. .. 12 days .. .. .. .. 7 days .. ..
1 14 26 33
14-d CIDR
GnRH

PG
CIDR (14 days)
.. .. 9 days .. .. .. .. 7 days .. ..
1 14 23 30
Treatment day
Kojima et al., 2004
36
Experimental Procedures

• 352 yearling crossbred beef heifers at three
  locations Location 1 n 154 (Southeast
  Missouri) Location 2 n 113 (North Dakota)
  Location 3 n 85 (North central Missouri)
• Heifers were assigned to one of two treatments
  (MGA or CIDR) by age and weight

Kojima et al., 2004
37
Summary for Timing of AI
80
69
70
60
53
50
of Heifers Inseminated
40
30
21
PG
20
16
15
10
10
10
5
1
0
0
0
1
2
3
4
5
Days after PG

• No treatment x location effect (P gt 0.10)
  therefore, data were pooled
• Distribution of AI dates were different between
  MGA- and CIDR-treated heifers (P lt 0.02)

Kojima et al., 2004
38
Estrous Response, AI Pregnancy, and Final
Pregnancy Rates
Estrous Response
AI Pregnancy
FinalPregnancy
112/177 (63 )a
154/177 (87 )
164/177 (93 )
CIDR
83/175 (47 )b
147/175 (84 )
159/175 (91 )
MGA
195/352 (55 )
301/352 (86 )
323/352 (92 )
Total
a, b P 0.01
3
Diff.
16
2
Kojima et al., 2004
39
Summary

• In yearling beef heifers
• CIDR-GnRH-PG improved synchrony of estrus
  compared with MGA Select
• CIDR-GnRH-PG improved AI pregnancy rate over
  MGA Select

Kojima et al., 2004
40
COWS
41
How do MGA-based protocols perform in
synchronizing estrus in mixed populations of
postpartum beef cows? (estrous cycling and
anestrus)
42

• Precise control of the bovine estrous cycle
  requires the synchronization of both luteal and
  follicular functions.

43
Protocols
MGA Select
PG
GnRH
MGA (14 days)
1 14 26 33
7-11 Synch
GnRH
PG
MGA
1 7 11 18
Treatment day
Kojima et al., 2000 Wood et al., 2001
44
These protocols were hypothesized to

• Improve estrous response and pregnancy rates
  during the synchronized period
• Effectively synchronize estrus in estrous
  cycling cows
• Induce cyclicity in anestrous cows
• Prevent short cycles among anestrous cows
  induced to ovulate

45
These protocols were hypothesized to

• Reduce the period of time required to detect
  estrus
• Facilitate fixed-time AI

46
How do MGA Select and 7-11 Synch compare on the
basis of synchronized estrus and pregnancy rates
in postpartum beef cows with AI performed on the
basis of detected estrus?
47
MGA Select vs. 7-11 SynchAI performed after
detected estrus

• No difference in estrous response
• Improvement in synchrony of estrus among 7-11
  Synch treated cows (P lt 0.01)
• No difference in synchronized conception or
  pregnancy rates
• No difference in final pregnancy rate
• Stegner et al., 2004

48
45
MGA Select
40
7-11 Synch
35
30
25
Cows in estrus, no
20
15
10
5
0
0
12
24
36
48
60
72
84
96
108
120
132
144
NR
Time after PG, h
Stegner et al., 2004
49
Pregnancy Rates of Cows Inseminated after
Detected Estrus
Pregnancy rate No. () MGA
Select Patterson et al., 2001 67/103
65 Patterson et al., 2002 67/101 66 Stegner
et al., 2003 61/109 56 Combined
total 195/313 62 7-11 Synch Kojima et al.,
2001 30/44 68 Stegner et al.,
2003 71/111 64 Combined total 101/155 65
50
How do MGA Select and 7-11 Synch compare on the
basis of pregnancy rates in postpartum beef cows
inseminated at predetermined fixed times?
51
MGA Select
Time of AI after PG
Pregnancy rate
48 hr
46
Stevenson et al., 2003
72 hr
61
Perry et al., 2002
72 hr 80 hr
64 50
Stegner et al., 2003
52
7-11 Synch
Pregnancy rate
Time of AI after PG
72
48 hr
Hixon et al., 2001
52 59
48 hr 60 hr
Kojima et al., 2003
61
60 hr
Unpublished data., 2002
63
60 hr
Kojima et al., 2002
63
60 hr
Kojima et al., 2003
53

• Bader et al. (2004) compared pregnancy rates
  resulting from fixed-time AI among suckled beef
  cows assigned to the MGA Select or 7-11 Synch
  protocols.

54
Protocols
MGA Select
PG
MGA (14 days)
1 14 26 33 72 hr
7-11 Synch
PG
MGA
1 7 11 18 60 hr
Treatment day
Bader et al., 2004
55
Days postpartum, body condition score, and
estrous-cycling status prior to initiation of
synchronization treatments
Location Days postpartum Body condition score Estrous cycling Estrous cycling
No.
1 50 1.0a 5.8 0.1a 64/208 31a

2 39 1.3b 5.8 0.1a 31/122 25a,b

3 36 1.5b 5.4 0.1b 18/92 20b

Combined 42 d 5.7 113/422 27
a,b(P lt 0.05)
Bader et al., 2004
56
Fixed-time AI and final pregnancy rates
Location Treatment Fixed-time AI Fixed-time AI Final Final
No. No.
1 7-11 Synch 64/104 62 95/104 91
1 MGA Select 68/104 65 101/104 97

2 7-11 Synch 34/60 57 57/59 97
2 MGA Select 43/62 69 60/62 97

3 7-11 Synch 30/45 67 43/45 96
3 MGA Select 31/47 66 42/47 89

Combined 7-11 Synch 128/209 61 195/208 94
Combined MGA Select 142/213 67 203/213 95
Bader et al., 2004
57
Fixed-time AI pregnancy rate based on
pretreatment estrous cyclicity status
MGA Select MGA Select MGA Select MGA Select 7-11 Synch 7-11 Synch 7-11 Synch 7-11 Synch
Cycling Cycling Anestrus Anestrus Cycling Cycling Anestrus Anestrus
Location No. Preg No. Preg No. Preg No Preg
1 20/30 67 48/74 65 24/34 71 40/70 57
2 12/16 75 31/46 67 9/15 60 25/45 56
3 6/8 75 25/39 64 8/10 80 22/35 63

Combined 38/54 70 104/159 65 41/59 69 87/150 58
Bader et al., 2004
58
Pros and Cons
Advantages Disadvantages
MGA Select - effective in mixed
- treatment length
populations - MGA intake
- synchrony of estrus
- fertility
after treatment
7-11 Synch - effective in mixed
- multiple
populations animal
handlings - exceptional
synchrony - drug costs
of estrus -
MGA intake
- fertility after treatment
- treatment duration
59
Pregnancy rates after AI based on detected estrus
or at predetermined fixed times
Pregnancy rate No. () 7-11
Synch Detected estrus 101/155
65 Fixed-time AI 446/728 61 MGA
Select Detected estrus 195/313
62 Fixed-time AI 281/436 64
60
Implications

• This sequential approach to estrous cycle control
  (progestin-GnRH-PG) effectively synchronizes
  estrus with resulting high fertility among mixed
  populations of estrous cycling and anestrous
  postpartum beef cows.

61
(No Transcript)
62
How do MGA- and CIDR-based protocols compare on
the basis of pregnancy rates in postpartum beef
cows inseminated at predetermined fixed
times?
63
MGA Select vs. CO-Synch CIDRSchafer, 2005
GnRH
GnRH
PG
MGA (14 d)
1
14 26
33
PG
GnRH
GnRH
CIDR (7 d)
0 7.
Treatment day
64
Timing of Insemination

• Time of AI Pregnancy
• Protocol after PG rate
  
• MGA Select
• Stevenson et al., 2003 48 h
  46
• Perry et al., 2002 72 h
  61
• Bader, 2004 72 h 67
• Stegner et al., 2004 72 h
  64
• 80 h 50
• CO-Synch CIDR
• Lamb et al., 2000 48 h 56
• 48 h 56
• Bremer et al., 2004 54 h
  67
• 66 h 71
• Larson et al., 2004 60 h 54

65
MGA Select vs. CO-Synch CIDRSchafer, 2005
GnRH
PG
MGA (14 d)
1
14 26
33 72h
PG
GnRH
CIDR (7 d)
0 7 ... 66h
Treatment day
66
Experimental ProceduresSchafer, 2005

• Animals Crossbred, suckled, beef cows (n
  650) at four locations were assigned to treatment
  within age groups by calving date and BCS

67
Experimental ProceduresSchafer, 2005

• Four different AI sires were used
• Location 1 3
• Location 2 1
• Location 3 1
• Location 4 1
• One of the sires that was used at location 1 was
  the same sire used at Locations 3 4

68
Experimental ProceduresSchafer, 2005

• Cows were exposed to fertile bulls 14 d after AI
• Pregnancy rate to fixed-time AI was determined
  with ultrasound 40 45 d after insemination

69
Number of cows at each location, DPP, BCS, and
estrous-cycling status prior to initiation of
synchronization treatments (Schafer,
2005)
Location Days postpartum Body condition score Estrous cycling No. Estrous cycling No.
1 46 5.7 112/210 53
2 33 6.0 63/158 40

3 44 5.3 31/88 35

4 43 5.3 156/194 80

Combined 42 d 5.5 362/650 56
70
Fixed-time AI pregnancy rates between treatments
and among locations (Schafer, 2005)
Location Treatment Fixed-time AI Fixed-time AI
No.
1 MGA Select 70/106 66
1 CO-SynchCIDR 67/104 64

2 MGA Select 53/80 66
2 CO-SynchCIDR 56/78 72

3 MGA Select 26/45 58
3 CO-SynchCIDR 29/43 67

4 MGA Select 52/96 54
4 CO-SynchCIDR 62/98 61
71
Pregnancy rates to fixed-time AI Schafer, 2005

• Pregnancy rate
• Treatment No.
• MGA Select 201/327 61
• CO-SynchCIDR 214/323 66

72
Fixed-time AI pregnancy rate based on
pretreatment estrous cyclicity status (Schafer,
2005)
MGA Select MGA Select MGA Select MGA Select CO-SynchCIDR CO-SynchCIDR CO-SynchCIDR CO-SynchCIDR
Cycling Cycling Anestrus Anestrus Cycling Cycling Anestrus Anestrus
Location No. Preg No. Preg No. Preg No Preg
1 38/62 61 32/44 73 30/50 60 37/54 69
2 20/29 69 33/51 65 25/34 74 31/44 70
3 11/16 69 15/29 52 8/15 53 21/28 75
4 41/78 53 11/18 61 50/78 64 12/20 60

Combined 110/185 59 91/142 64 113/177 64 101/146 69
73
Conclusions Schafer, 2005

• The results from this experiment demonstrate that
  comparable pregnancy rates to fixed-time AI can
  be achieved using the MGA Select or CO-SynchCIDR
  protocols to synchronize estrus in postpartum
  beef cows.

74
Do we know what to expect at calving from cows
that conceive on the same day to the same sire?
75
A Angus 6.2 BW 272-292, 20 d
B Angus 3.3 BW 275-292, 17 d
C Red Angus 1.5 BW, 2 CED 274-289, 15 d
D Simmental -0.6 BW, 14.8 CE 275-294, 19 d
25
B Angus 3.3 BW 274-291, 17 d
20
15
of AI calves born
10
5
0
-11
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
3
4
5
6
Days relative to 285 d gestation due date Bader
et al., 2004
76
Location 1 Sire B (Angus) BW EPD 3.5 CED
6 Range 275-292 Mean 281
Location 1 Sire C (Angus) BW EPD -1.1 CED
11 Range 274-287 Mean 281
Location 1 Sire A (Angus) BW EPD -0.3 CED
11 Range 271-290 Mean 281
Location 2 Sire D (Red Angus) BW EPD 2.3
CED -2 Range 273-300 Mean 283
Location 3 Sire B (Angus) BW EPD 3.5 CED
6 Range 272-294 Mean 283
Location 4 Sire B (Angus) BW EPD 3.5 CED
6 Range 275-294 Mean 284
77
Calving Distribution of AI sired calves (Schafer
et al., 2005)
78
Consider the impact of estrus synchronization
on calving distribution
79
Hughes, 2005

• Opportunities for increasing profits lie in
  managing females from the later calving intervals
  forward toward the first and second calving
  intervals.
• High production herds see 61 of the calves born
  by day 21, 85 by day 42 and 94 by day 63.

80
100
MGA Select
90
7-11 Synch
80
70
60
Cows calving,
50
40
30
20
10
0
First 15 d
First 30 d
Calving period
Stegner et al., 2004
81
Calving distribution for locations 1, 2, 3
(Schafer, 2005)
Cumulative Calf by day 15 64 day 21
70 day 30 77 day 42 91
82
MU Forage Systems Research Center cumulative calf
crops
83
Cumulative calf crops (MU Thompson Farm) for the
first 46 days over 10 calving seasons
84
Conclusions and Implications
85
Estrous response and fertility in postpartum beef
cows after treatment with various estrus
synchronization protocols.
Treatment Estrous response
Pregnancy rate
AI based on detected estrus No.
No.

2 shot PG Select Synch MGA-PG MGA Select 7-11
Synch
241/422 57 353/528 67 305/408
75 275/313 88 142/155
92
147/422 35 237/528 45 220/408
54 195/313 62 101/155
65
Fixed-time AI MGA Select 7-11 Synch CO-Synch
CIDR
482/763 63 446/728 61 214/323
66
DeJarnette and Wallace
86
Estrous response and fertility in postpartum beef
cows after treatment with various estrus
synchronization protocols.
Treatment Estrous response
Pregnancy rate
AI based on

detected estrus No.
No.

2 shot PG Select Synch MGA-PG MGA Select 7-11
Synch
241/422 57 353/528 67 305/408
75 275/313 88 142/155
92
147/422 35 237/528 45 220/408
54 195/313 62 101/155
65
Fixed-time AI MGA Select 7-11 Synch CO-Synch
CIDR
482/763 63 446/728 61 214/323
66
DeJarnette and Wallace
87
CO-Synch CIDR Results (FTAI _at_ 66 hr after PG) CO-Synch CIDR Results (FTAI _at_ 66 hr after PG) CO-Synch CIDR Results (FTAI _at_ 66 hr after PG) CO-Synch CIDR Results (FTAI _at_ 66 hr after PG)
Herd (Year) No. Pregnant Total No. Percentage
1 (F03) 41 51 80
2 (S04) 67 104 64
3 (S04) 56 78 72
4 (S04) 29 43 67
5 (S04) 52 96 63
6 (S04) 60 90 67
7 (F04) 31 48 65
8 (F04) 87 143 61
9 (F04) 61 100 61
10 (F04) 44 69 63
11 (F04) 68 111 61
12 (F04) 47 60 78
13 (S05 143 224 64
Total 786 1217 65
88

• Research is underway to develop new protocols
  for heifers that will facilitate fixed-time AI .
• The technology now exists to successfully
  inseminate postpartum beef cows at predetermined
  fixed times with resulting high pregnancy rates .
  . . . . . . . .

89

• Improvements in methods to synchronize estrus
  create the opportunity to significantly expand
  the use of AI in the U.S. cowherd . . . . . . .

90
AcknowledgementsFaculty, Students, Staff

• Jon Bader Dr. George Perry
• Roger Eakins Daniel Schafer
• Dr. Mark Ellersieck Jon Schreffler
• Freddie Kojima Dr. Mike Smith
• Dr. Matthew Lucy Jacob Stegner
• David McAtee Stacey Wood (Follis)

91
Acknowledgements
Research Support Cooperators Select Sires,
Inc. 4-M Ranch KABA/Select Sires, Inc. John
Ranch ABS Global Jim Wallis Farms Merial
Jim Clement, DVM Pfizer Animal Health SEMO
University USDA-NRI MFA, Inc. MU
Farms Centers
92
Acknowledgements
Beef Reproduction Leadership Team AI
industry Pharmaceutical industry Veterinary
practitioners North Central Region Bovine
Reproduction Task Force