estrus and ovulation synchronization in beef heifersdepartment/deptdocs... · estrous cycle of the...
TRANSCRIPT
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Estrus and ovulation
synchronization in beef
heifers
Dr. Marcos G Colazo Research Scientist, Alberta Agriculture & Rural
Development
Edmonton, Alberta, Canada E-mail: [email protected]; [email protected]
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Outline of talk
Estrous cycle of the heifer
What is CR and PR?
Controlling the estrous cycle – Synchronization of estrus – Synchronization of ovulation – Protocols
Advantages and disadvantages
Cost
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Estrous cycle of the heifers
Average 21 days long (18 to 24)
Two phases luteal and follicular
Four stages – Proestrus (Day 18-20)
– Estrus (Day 0)
– Metestrus (Day 1 - 3)
– Diestrus (Day 4 - 17)
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Pregnancy Rate (PR) =
Estrus Detection Efficiency (EDE) x
Conception rate (CR)
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n EDE CR PR
(%) (%) (%)
100 50 50 25
100 80 50 40
100 100 50 50
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Shortening the luteal phase
(e.g.)
ProstaglandinF2
Simulating the luteal phase
(e.g.)
Progesterone
Controlling the estrous cycle
Controlled follicle growth & ovulation
(e.g.)
Estrogens & GnRH
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Commercially available PGF products
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0 7 14 21
Active CL, D 5-16
PGF effective
5
10
15
20
Day of cycle
Follicle s
ize (mm)
Growing CL Regressing CL
Ov Ov
Estrus Pro estrus Diestrus Metestrus
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Common Protocols using PGF
Estrus detection and AI
Estrus detection and AI
Estrus detection and AI
6 days
14 days PGF PGF
PGF PGF
PGF
Estrus detection and AI
11 days
EDR~80%
EDR~85%
EDR~85%
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Distribution of heat in beef heifers given PGF 11 d apart
0
10
20
30
40
50
60
% in
heat
24 36 48 60 72 84 96
Hours after second PGF
Total in heat: 84%
Butler et al., 2001
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0
10
20
30
40
50
60
% in
heat
36 48 60 72 84 96 108 120 132 144
Hours after second PGF
Total in heat: 86%
Colazo, unpublished
Distribution of heat in Holstein heifers given PGF 14 d apart
n = 132
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Conception Rate
0
10
20
30
40
50
60
70
80
90
100
%
P
r
e
g
n
a
n
t
14 d apart PGF
5d Modified Cosynch
a, b Effect of TRT P < 0.05
a
b
80.9% 60.0%
~half AI with sexed semen
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Shortening the luteal phase
(e.g.)
ProstaglandinF2
Simulating the luteal phase
(e.g.)
Progesterone
Controlling the estrous cycle
Controlled follicle growth & ovulation
(e.g.)
Estrogens & GnRH
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Oral Progestins: Melengestrol Acetate (MGA)
Ear implants Crestar
Intravaginal Devices
PRID CIDR-B DIB TRIU-B CUE-MATE
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Program with MGA for estrus synchronization
MGA Day 0 14
PGF ED + AI
31/33
(17/19 days)
MGA = melengestrol acetate @ 0.5 mg/heifer/day
NO AI
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Modified MGA program (MGA select)
MGA Day 0 14
PGF ED + AI
33
NO AI
GnRH
26
Wood-Follis et al., 2004
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MGA/PGF vs. MGA Select (ED + AI for 6 days)
80 93 80 96
0
10
20
30
40
50
60
70
80
90
100
MGA/PGF MGA select
Wood-Follis et al., 2004
66 67 63 82
0
10
20
30
40
50
60
70
80
90
MGA/PGF MGA select
N = 124
Estrus rate Pregnancy rate
Anestrus Cycling
* *
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Increase estrus detection rate
– Aggressive estrus detection
– Increased frequency of observation
– Use of estrus-detection aids
Tail paint, Kamar, electronic aids
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Shortening the luteal phase
(e.g.)
ProstaglandinF2
Simulating the luteal phase
(e.g.)
Progesterone
We used them in combination for TAI
Controlling the estrous cycle
Controlled follicle growth & ovulation
(e.g.)
Estrogens & GnRH
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17
Benzoate
Valerate
Cipionate
Days after treatment
1 2 3 4 5 6 7 8 9
Plasma concentrations
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TAI protocol (Progesterone & Estrogen)
Insert CIDR
Give
1 or mg EB
o 5 mg E-17B
Remove CIDR
Give PGF
1 mg EB TAI
DAY 0 7 9 10
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MON am
TUE am
WED pm
THU FRI SAT SUN
EB or 17B
CIDRi
CIDRr
PGF
EB TAI
TAI protocol-Schedule (Progesterone & Estrogen)
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Pregnancy rate in heifers treated with E17B or EB
n = 1428 heifers
65
5659
46
0
10
20
30
40
50
60
70
80
90
100
%
E17B BE
Cyclic
Acyclic
Colazo unpublished
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TAI protocol (Progesterone & Estrogen)
Insert CIDR
Give
5 mg E-17B
Remove CIDR
Give PGF 0.5 mg ECP
TAI
DAY 0 7 9 10
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PREGNANCY RATES
Colazo et al., 2003
63.3 64.6 63.1
0
10
20
30
40
50
60
70
80
ECP0 (n=98) ECP24 (n=99) EB24 (n=103)
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Pregnancy rate for cattle inseminated 24 versus 36 h after second EB treatment
Colazo et al., 2005
49.1
69.8
0
10
20
30
40
50
60
70
80
24 h (n=57) 36 h (n=53)
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Some commercially available GnRH products
Fertagyl (Merck Animal Health)
Fertiline (Vetoquinol)
Factrel (Pfizer Animal Health)
Cystorelin (Merial)
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Induced ovulation
New follicle growth
CL regression and
Follicle maturation
Synchronized
Ovulation
GnRH GnRH PGF AI
7 d 16 h 2 d
D 0 D 7 D 9 D 10
How Ovsynch works?
Pursley et al., 1995
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Cosynch
Second GnRH given at time of AI
Advantage: Reduced handling
Possible disadvantage: Delayed ovulation
GnRH GnRH PGF AI
7 d 0-12 h 2 d
D 0 D 7 D 9 D 10 GnRH +
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Pregnancy Rates (%)
Geary et al., 2001
0
10
20
30
40
50
60
Cosynch Ovsynch
n = 360 n = 392
54% 52%
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Pregnancy rates to AI in cows and heifers after estrus or Ovsynch
IDE% OVS/TAI% P
Cows 39 (154) 38 (156) >.10
Heifers 74 (78) 35 (77) <.01
P <.01 >.10
Pursley et al. (1997) JDS 80:295
Ovsynch/Timed AI is not effective in heifers
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Cosynch plus CIDR or PRID
GnRH PGF GnRH&AI
56-60 h
D 0 D 7 D 10
CIDR or PRID
In
D 0
Out
D 7
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Pregnancy rate
Category Cosynch CIDR+Cosynch
Cows n = 71 n = 77
45.1% 42.9%
Heifers n = 23 n = 25
39.1%a 68.0%b
ab (P<0.05).
Martinez et al., 2002
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MON am
TUE am
WED pm
THU FRI SAT SUN
GnRH
CIDRi
CIDRr
PGF
GnRH& TAI
TAI protocol-Schedule (7d Cosynch & CIDR)
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Experimental Design - 5 d vs 7 d Cosynch
GnRH PGF2α
GnRH
7 d CIDR
5 d CIDR
PGF2α
d -7
d -5
d 0 GnRH
+ AI
60 h
d 0
72 h
Day et al., 2006
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0
10
20
30
40
50
60
70
80
Jackson Belle Valley Overall
7-d CIDR 5-d CIDR
Timed AI Pregnancy Rate 5 d vs 7 d Cosynch
Pre
gn
ancy
Rat
e, %
Trt, P<.03; TrtxLoc, P=.08
(n=150) (n=250) (n=400)
Day et al., 2006
53% 73% 58% 61% 56% 65%
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TAI Pregnancy Rate
0
10
20
30
40
50
60
70
80
90
100
%
P
r
e
g
n
a
n
t
CO-Synch 5d CIDR
CO-Synch 7d CIDR
a, b Effect of TRT P < 0.03
a
b
120/201 100/204
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Experimental Design – Modified 5 d Cosynch
GnRH
5 d PRID
PGF2α
d -5 d 0
72 h
Colazo and Ambrose, 2011
GnRH
+ AI
5 d PRID
PGF2α
d -5 d 0
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Timed-AI Pregnancy Rate
0
10
20
30
40
50
60
70
80
905-d Cosynch PRID5-d Modified Cosynch PRID
Trt, P >0.05 Treatment
n=28 n=28
Pre
gnan
cy R
ate,
%
Colazo and Ambrose, 2011
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MON am
TUE am
WED am
THU am
FRI SAT SUN
GnRH
PRIDi
PRIDr
PGF
PGF GnRH& TAI
TAI protocol-Schedule (5d Cosynch & PRID)
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Timed-AI programs: Overall results
Studies published between 2000 and
2006
Treated beef heifers: 3109
GENMOD en SAS
Pregnancy rate: 53.9 %
Range: 47,3 % to 70,0 %
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n = 3110 heifers
56*
49
0
10
20
30
40
50
60
70
Cyclic Acyclic
P < 0.01
Timed-AI programs (Cycling vs. anestrus)
26%
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Calving distribution of 90 beef heifers all bred on a single day
0
2
4
6
8
10
12
14
No
. of
calv
ing
s
270 272 274 276 278 280 282 284 286
Gestation length (days)
Reuter and Rinette, 2009 N = 90
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Groups CIDR MGA
Control CIDR +E/P +E/P/E MGA +E/P +E/P/E
Preg. to 1st AI (%) 45.2ab 47.3a 49.5a 33.3b 54.8a 45.2ab 48.4a
42 44 46 31 51 42 45
Estrus rate (%) 88.2ac 91.8ab 95.7a 95.2a 83.3bc 84.3c 77.1c n 45/51 45/49 45/47 59/62 35/42 43/51 37/48
Conception rate (%) 62.2ab 64.4ab 73.3a 59.3b 40.0c 53.5bc 54.0bc n 28/45 29/45 33/45 35/59 14/35 23/43 20/37
Pregnancy rate (%) 54.9ab 59.2ab 70.2a 56.4ab 33.3c 45.1bc 41.7bc n 28/51 29/49 33/47 35/62 14/42 23/51 20/48 TAI & Rebreeding 75.3ab 78.5ab 84.9ac 71b 69.9b 69.9b 69.9b
abcdPercentages are different (P<0.05)
Resynchronization of timed inseminated heifers with a used CIDR or MGA and E/P
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983 beef heifers TAI over 3 days
All received a used CIDR device
336 heifers reinseminated over 5 days (78.2%)
542 pregnant to TAI (55.2%) and 232 pregnant to re-insemination
Overall PR of 78.7%
Resynchronization of heifers with a used CIDR (12,13 or 14 d after AI)
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Timed-AI programs: Cost per pregnancy based on 100 heifers
CIDR/EB CIDR/OVS CIDR/COS7 CIDR/COS5 CIDR/COSM5
$ 26.5 $ 30.0 $ 30.0 $ 35.0 $ 26.5
$ 300 $ 300 $ 240 $ 300 $ 240
$ 2500 $ 2500
$ 2500
$ 2500
$ 2500
65% 55% 50% 65% 60%
$ 83.8 $ 105.5 $ 114.8 $ 96.9 $ 89.8
Drugs
Labour
Semen + AI
Per Preg
PR
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May, 2004
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THANK YOU !
Marcos G Colazo Research Scientist, Alberta Agriculture & Rural
Development
Edmonton, Alberta, Canada E-mail: [email protected]; [email protected]