Setting up Lactating Dairy Cows for First Postpartum Timed AI

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Setting up Lactating Dairy Cows for First Postpartum Timed AI Professor of Dairy Science University of Wisconsin-Madison

Synch Timeline 1980 1985 1990 1995 2000 2005 2010 1979 Lutalyse approved for use in cattle 1986 Follicular waves discovered 1995 Ovsynch protocol published 2001 Presynch Ovsynch protocol published 2009 Double Ovsynch protocol published 1980 Targeted breeding system 2003 Resynch protocol comparison published 2008 Ovsynch56 protocol published Paul M. Fricke, Ph.D.

PGF2α TAI 7 Days 48 h 16 h

Conception Rate Conception Rate Vasconcelos, Pursley, & Wiltbank Conception rate, % 50 40 30 20 10 0 41 40 36 34 28 1-4 5-8 9-12 13-16 17-21 Day of estrous cycle

PGF2α TAI PGF2α PGF2α 14 days? days 7 days? h? h

Presynch/Ovsynch 14/12 Sun Mon Tue Wed Thu Fri Sat PGF PGF PGF TAI

Synchronization for first post-partum partum TAI using Presynch / Ovsynch PGF 2α PGF 2α PGF 2α + TAI EDAI 14 Days 14 Days 7 Days 3 Days 35 ± 3 49 ± 3 63 ± 3 70 ± 3 73 ± 3 Days Post-partum Paul M. Fricke, Ph.D.

Frequency of AI Relative to the Second PGF Injection of Presynch Paul M. Fricke, Ph.D.

Pre-Synchronization 12 d PGF2α PGF2α Day of Estrus d -14 d 0 d 2 d 3 d 4 d 5 d 6 d 7 d 12 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10

Pre-Synchronization 14 d PGF2α PGF2α Day of Estrus d -14 d 0 d 2 d 3 d 4 d 5 d 6 d 7 d 14 Day 7 Day 8 Day 9 Day 10 Day 11 Day 12

Two Follicular Waves Progesterone Follicular Size Dominance Deviation Atresia Ovulation Recruitment Ovulation 10 21 Day After Ovulation Paul M. Fricke, Ph.D.

Experimental Design Galvao et al., 2007 PGF2α TAI PGF2α PGF2α 14 Days 14 Days 7 Days 2 Days 16 h PGF2α TAI PGF2α PGF2α 14 Days 11 Days 7 Days 2 Days 16 h

Results Galvao et al., 2007 Item Conception Rate 14 d 11 d 38 d (%) 33.5 a (138/412) 66 d (%) 30.2 a (124/410) 40.5 b (166/410) 36.4 b (149/409) a,b Proportions differ (P<0.05)

Presynch/Ovsynch 14/11 Sun Mon Tue Wed Thu Fri Sat PGF PGF PGF TAI

Presynch/Ovsynch 14/10 Sun Mon Tue Wed Thu Fri Sat PGF PGF PGF TAI

Presynch/Ovsynch 14/12 Sun Mon Tue Wed Thu Fri Sat PGF PGF PGF TAI

Presynch/Ovsynch 14/12 Sun Mon Tue Wed Thu Fri Sat PGF PGF PGF TAI

Bad things that happen when you breed a cow that is not in estrus: 1) She fails to conceive 2) Her interval to rebreeding increases 3) You discontinue a program that gives her an excellent chance to conceive 4) Cycling cows have greater fertility to Presynch/Ovsynch than anovular cows

PGF2α TAI PGF2α PGF2α 14 days 10 to 12 days 7 days? h? h

Timing of AI Relative to Synchronized Ovulations in Lactating Dairy Cows Paul M. Fricke Professor of Dairy Science University of Wisconsin - Madison

Behavioral Estrus in Dairy Cattle PM Fricke, Ph.D.

When does ovulation occur? 27.6 ± 5.4 h after the first standing event of estrus Walker et al., 1996. J. Dairy Sci. 79:1555 All cows (n=20) ovluated within 24 to 32 h after the second injection of Ovsynch Pursley et al., 1995. Theriogenology 44:915 Thus, timing of ovulation is similar when comparing the interval to ovulation from the first standing event of estrus and the second injection of Ovsynch Paul M. Fricke, PhD

Effect of interval from first standing event of estrus on conception rate of lactating dairy cows Interval from onset of estrus to AI (h) AI (no.) Conception rate (%) Odds ratio 95% confidence interval 0 to 4 327 43.1 1.00 >4 to 8 735 50.9 1.35 1.03 1.77 >8 to 12 677 51.1 1.33 1.01 1.75 >12 to 16 459 46.2 1.12 0.83 1.50 >16 to 20 317 28.1 0.51 0.36 0.71 >20 to 24 139 31.7 0.57 0.37 0.87 >24 to 26 7 14.3 0.18 0.02 1.56 Dransfield et al., 1998. J. Dairy Sci. 81:1874-1882.

Experimental Design Pursley et al., 1998. J. Dairy Sci. 81:2139-2144 G P G 7 days 2 days AI AI AI AI AI O h (n=149) 8 h (n=148) 16 h (n=149) 24 h (n=143) Ovulation 32 h (n=143)

Conception Rates of Lactating Cows Receiving TAI at Various Intervals from the Second Injection of Ovsynch Pursley et al., 1998. J. Dairy Sci. 81:2139-2144. Conception Rate (%) 50 45% 41% 41% 40 37% 32% 30 20 10 0 0 8 16 24 32 Hours after 2nd Injection

Comparison among Cosynch and Ovsynch 56 protocols Brusveen et al., 2008. J. Dairy Sci. 91:1044-1052. Cows were submitted for TAI after Presynch or as Resynch treatment 1507 TAI in 927 lactating Holstein cows PGF 7 Days 48 h +TAI 27% n=493 PGF 7 Days 56 h 16 h TAI 36% n=494 PGF 7 Days 72 h +TAI 23% n=494

72 h Cosynch vs. Ovsynch 56 Current: 72 h Cosynch 1 st TAI = 22% Resynch TAI = 24% Desired: Ovsynch 56 1 st TAI = 43% Resynch TAI = 30% Percent Pregnant (%) 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Current Desired 100% HD Max DIM AI 0 50 100 150 200 250 300 350 400 450 DIM $6.70 Economic impact $6.60 NPV ($/cow/day) $6.50 $6.40 $6.30 $6.20 $6.10 $6.00 $5.90 $6.09 $6.60 $6.45 $0.51 per cow/day $186,150 per 1,000 cows/year $5.80

Comparison of first postpartum TAI after Ovsynch 56 and Cosynch 72 protocols in lactating dairy cows Treatment Parity Ovsynch 56 Cosynch 72 P-value Primiparous 37 (134) 31 (148) 0.33 Multiparous 47 (204) 25 (253) <0.05 Overall 43 (338) 27 (401) Nebel et al., 2008. J. Dairy Sci. 90(E-suppl. 1):248 (Abstr.)

Timing of the 2 nd injection and TAI - Conclusions Although Cosynch protocols are often times easier to implement on dairies, Timing of AI in relation to the timing of ovulation is not optimized Ovsynch 56 yields significantly greater fertility than Cosynch 48 or Cosynch 72 STOP DOING COSYNCH!

PGF2α PGF2α PGF2α 14 Days 10 to 12 Days 7 Days 56 h

New Presynchronization Strategies

Item Cows Heifers Estrus duration (h) 7.3 ± 7.2 11.3 ± 6.9 Conception rate (%) <50 >50 Pregnancy Loss High Low Multiple ovulation (%) 14 5 Twinning rate (%) 8 ~1

Novel Hypothesis Dr. Milo Wiltbank, UW-Madison Liver Blood Flow High Feed Intake Metabolism of Ovarian Steroids Visceral Blood Flow High Milk Production r = 0.88; Harrison et al., J. Dairy Sci. 73:2749; 1990 Decreased Circulating Estrogen & Progesterone

Implications for Reproduction Estrus Behavior Attenuated expression and duration of estrus (Harrison et al., J Dairy Sci 73:2749; 1990) Follicular development Number of follicular waves per cycle (Cordoba and Fricke, J Dairy Sci, 2002) Reduction in Oocyte and embryo quality (Sartori et al., 2004) Increased multiple ovulations and twinning (Fricke and Wiltbank, Therio 52:1133; 1999) Fertility Increased early embryonic loss (Vasconcelos et al., Biol Reprod 56(Suppl. 1):140(Abstract); 1997)

Implications for Reproduction I am NOT implying that you should attempt to decrease milk production to improve reproduction Higher producing herds usually have better reproductive performance than lower producing herds (management) Higher producing dairy cows often have better reproductive performance than lower producing dairy cows (health) Dairy producers get paid for the milk they produce (economics) A better understanding of the mechanism underlying this hypothesis may allow for improved management of reproduction

Problems in fertility related to steroid metabolism Low P4 Before AI Low E2 Before AI Low P4 After AI E2 Post-AI

G6G Schedule Sun Mon Tue Wed Thu Fri Sat PGF PGF TAI

Double Your Pleasure Double Your Fun

Double Ovsynch Schedule for first TAI Sun Mon Tue Wed Thu Fri Sat PGF TAI

Double Ovsynch Schedule for first TAI Sun Mon Tue Wed Thu Fri Sat PGF PGF TAI

Presynch/Ovsynch Schedule for first TAI Sun Mon Tue Wed Thu Fri Sat PGF PGF PGF TAI

Effect of synchronization protocol on pregnancies per AI, DIM, lactation number, BCS and locomotion score in lactating dairy cows Souza et al., Theriogenology 2009. Double Ovsynch P/AI (%) 50 (78/157) DIM (range) 77.0 ± 0.16 (74 81) Lactation Number (range) 2.2 ± 0.12 (1 11) BCS (range) 2.91 ± 0.03 (2.25 4.00) Locomotion Score (range) 1.45 ± 0.08 (1 5) Presynch Ovsynch 42 (75/180) 77.2 ± 0.15 (74 81) 2.4 ± 0.13 (1 10) 2.89 ± 0.02 (2.25 4.25) 1.48 ± 0.07 (1 4) P-value 0.03 0.57 0.64 0.54 0.34

Presynch/Ovsynch Double Ovsynch Current: Presynch/Ovsynch Conception rate = 42% Desired: Double Ovsynch Conception rate = 50% Percent Pregnant (%) 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Current Desired 100% HD Max DIM AI 0 50 100 150 200 250 300 350 400 450 DIM $6.75 Economic impact $6.70 NPV ($/cow/day) $6.65 $6.60 $6.55 $6.50 $6.45 $6.40 $6.35 $6.64 $6.72 $6.45 $0.08 per cow/day $29,200 per 1,000 cows/year $6.30

Effect of treatment on fertility 39 to 45 d after TAI Souza et al., Theriogenology 2008 Effect P-value Treatment 0.03 Parity 0.02 n=73 n=107 n=69 n=88

Study 1: Optimizing the Efficiency of Double-Ovsynch for First Artificial Insemination University of Wisconsin Madison Reproduction Laboratory

Double-Ovsynch for 1 st TAI PGF 2α PGF TAI 2α 7 d 3 d 7 d 7d 56h 16h Pre-Ovsynch Breeding-Ovsynch

Pregnancises per AI 29 d post TAI P > 0.05 P\AI (%) n=263 n=270 n=277 n=274

Main effect of dose P > 0.05 n=533 n=551

Main effect of PGF dose P > 0.05 n=540 n=544

Effect of Parity P < 0.001 n=519 n=565

Effect of Parity on Luteal Regression Giordano et al., unpublished Parity group Item Primiparous Multiparou s Luteal regression, % (n/n) P-value All cows 95.7 (288/301) Cows not ovulating to 1 st 99.0 (102/103) Cows ovulating to 1 st 93.9 (185/197) 91.1 (296/325) 95.2 (99/104) 89.0 (195/219) 0.05 0.07 0.02

Double Ovsynch Schedule with or without additional PGF Sun Mon Tue Wed Thu Fri Sat PGF PGF +PGF AI

Effect of Second PGF 2α Treatment Overall P/AI Low P4 (%) P/AI-First Service Single PGF 2α 41.5% (163/393) 84.6% (301/356) 47.0% (109/232) Double PGF 2α 44.7% (169/379) 95.6% (326/341) 52.7% (117/221) P -value 0.17 <0.001 0.12

P/AI First Service TAI 1ST AI 100.0% 90.0% 80.0% 70.0% 60.0% 50.0% 40.0% 30.0% 20.0% 10.0% 0.0% 1ST AI Breeding date

5-Day Ovsynch Schedule Sun Mon Tue Wed Thu Fri Sat PGF PGF

A second PGF injection was given 12 h after the initial PGF for all cows. 60 h Cosynch protocol was used. Timed AI CR was 13.3% (Exp 1) and 9.1% (Exp 2) greater for the 5 than the 7 day protocol.

Effect of Reducing the Period of Follicle Dominance in a Timed Artificial Insemination Protocol on Reproduction of Dairy Cows J. Dairy Sci. 93:2976-2988; 2010 J.E.P. Santos, C.D. Narciso, F. Rivera, W.W. Thatcher, and R.C. Chebel

Santos et al., J. Dairy Sci. 93:2976; 2010

Results, Expt. 1 Santos et al., J. Dairy Sci. 93:2976; 2010. Treatment Item CoS72 5dCoS1 5dCoS2 CL regression at AI, % (n) All cows 79 b (57) 59 c (44) 96 a (47) Cows ovulating to first 71 b (35) 52 c (29) 96 a (25) Dia. of ovulatory follicle, mm At AI 18.3 a ± 0.6 17.5 a,b ± 0.6 16.5 b ±0.6 Ovulation to 2 nd, % (n) 89 (62) 79 (52) 84 (51) Synchronization rate 69 a (62) 42 b (52) 78 a (51) Within a row, means with different superscripts differ (P < 0.05)

Results, Expt. 2 Santos et al., J. Dairy Sci. 93:2976; 2010. Treatment Item CoS72 5dCoS2 P-value Ovulation to 1 st, % (n) 70 (171) 63 (162) 0.15 CL reg. at AI, % (n) All cows 92 (424) 96 (406) <0.01 Cows ovulating to 1 st 87 (114) 98 (95) <0.01 Ov. follicle dia. at AI (mm) 18.5 ± 0.3 17.1 ± 0.4 <0.01 Ovulation to 2 nd, % (n) 87 (175) 88 (168) 0.31 Ov. before 2 nd, % (n) 3 (175) 2 (168) 0.57 Synchronization, % (n) 74 (175) 81 (168) 0.07

Results, Expt. 2 Santos et al., J. Dairy Sci. 93:2976; 2010. Treatment Item CoS72 5dCoS2 P-value Estrus at timed AI, % (n) 31 (408) 24 (411) <0.01 Pregnant, % (n) Day 38 31 (466) 38 (462) 0.02 Day 66 30 (466) 35 (461) 0.05 Pregnancy loss, % (n) 4 (144) 6 (174) 0.52

5-day Heifer CIDR Synch protocol day Heifer CIDR Synch protocol Thatcher et al, unpublished PGF 2α PGF Synch (n=120) PGF 2α +TAI 14 days CIDR Synch (n=127) PGF2α (AM/PM) 60 hours +TAI CIDR 5 days 3 days

Conception rate (32 d) of dairy heifers to TAI after PGF Synch or CIDR Synch Thatcher et al. Unpublished Treatments do not differ statistically n=120 n=127