Beef Semen Sales. Since ARSBC, Manhattan, Kan. EVOLUTION AND APPLICATION OF ESTROUS SYNCHRONIZATION PROTOCOLS

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EVOLUTION AND APPLICATION OF ESTROUS SYNCHRONIZATION PROTOCOLS Development of Methods to Synchronize Estrus DECADE 1950 s 60 s PHASE OF DEVELOPMENT PROGESTERONE Inhibited estrus & ovulation; prolonged luteal phase; created artificial luteal phase PROGESTERONE -ESTROGEN 1970 s Norgestomet & estradiol valerate (Syncro-Mate B) 1980 s PROGESTIN - PROSTAGLANDIN 1990 s - PROSTAGLANDIN 2000 s PROGESTIN - - PROSTAGLANDIN PROSTAGLANDIN Prostaglandin F2α and its analogs were found to be luteolytic DJ Patterson, JM Thomas, JWC Locke, BE Bishop, JM Abel, ER Knickmeyer, and MF Smith Division of Animal Sciences University of Missouri MGA- Ultrasound led to the understanding of follicular waves; Ov-synch; Select Synch; CO-Synch 2 1 3 4 Beef Semen Sales Since 2005 Heat detection! Cows! 6-d CIDR Heat detect & time! Heifers! 14-d CIDR- & T! Cows! 6-d CIDR Fixed-time! Heifers! 5-day CO-Synch + CIDR! 14-d CIDR-! Cows! 5-day CO-Synch + CIDR! 5-d CO-Synch + CIDR (Bos indicus) 5 2017 ARSBC, Manhattan, Kan. 6 1

Goals in developing FT protocols!ft estrus synchronization protocols "Easy to schedule and administer "Reduce animal handling "Result in a highly synchronized and fertile estrus and ovulation The next minutes..! Overview of protocols # Heifers # 2-year-olds # Mature cows # Split-time 7 8 FIXED-TIME PROTOCOLS FOR HEIFERS Short-term Protocols 7-day CO-Synch + 0 7 HEIFERS FIXED-TIME.. 54 ± 2 hr.. 9 Long-term Protocols 14-day - 0 14... 16 d 66 ± 2 hr 33 5-day CO-Synch + MGA - 8±2 hr 0 5..60 ± 4 hr.. 7 MGA 1 14 19 d 33 72 ± 2 hr 36 9 HOW DO LONG-TERM PROTOCOLS COMPARE IN HEIFERS? MGA 1 14 19 days 33 39 Heat detection and CIDR 0 14 16 days 36 Heat detection and 11 Mallory, et al., 2009 12 2017 ARSBC, Manhattan, Kan. 2

DISTRIBUTION OF ESTRUS AFTER MGA OR CIDR Estrus, % 45 40 35 25 20 15 5 0 60 MGA- 0 1 2 3 4 5 6 7 8 9 11 12 13 14 15 16 17 18 19 NR Interval after progestin removal, treatment d DISTRIBUTION OF ESTRUS AFTER 45 MGA- 40 35 14-day CIDR- 25 20 50 15 Estrus, % 40 20 14-day CIDR- Estrus, % 5 0 0-12 12-24 24-36 36-48 48-60 60-72 72-84 84-96 96-8 8-120 120-132 132-144 NR 0-3 -2-1 0 1 2 3 4 5 6 7 8 9 11 12 13 14 15 16 NR Interval after progestin removal, treatment d 13 Interval after administration, h 14 MGA- VS 14-DAY CIDR- MGA 1 14 33 72 hr 0 14 66 hr # Insemination performed on the basis of observed estrus # No differences in synchronized conception or pregnancy rates (Mallory et al., 2009) # FT # No differences in pregnancy rates (Vraspir et al., 2013) 15 16 CIDR (7 d) CIDR (7 d) THE MULTI-STATE CIDR TRIAL 0 7..84 h Detect estrus & 0 7...84 h Detect estrus & Lamb et al., 2006 CIDR (7 d) CIDR (7 d) 0 7... 60 h FT 0 7...60 h FT 17 Lamb et al., 2006 18 2017 ARSBC, Manhattan, Kan. 3

MULTI-STATE CIDR TRIAL! at CIDR insertion did not improve pregnancy rates after FT! at CIDR insertion did not alter the percentage of heifers detected in estrus or the distribution of estrus after 5-DAY CO-SYNCH + CIDR! A combination of detecting estrus and before cleanup enhanced pregnancy rates over FT Lamb et al., 2006 19 20 5-DAY CO-SYNCH + CIDR PREGNANCY RATES AFTER FT 5-d CO-Synch + CIDR FT at 60 h CIDR (5-d)..8 ± 2 h.....60 ± 4 h Protocol comparison Heifers (N) Pregnancy rate (%) P-value 7-day CO-Synch + CIDR vs 5-day CO-Synch + CIDR 14-day CIDR- vs 5-day CO-Synch + CIDR 292 1 52 vs 62 0.09 665 2 47 vs 57 0.05 3 3 70 vs 70 > 0. 524 4 53 vs 62 0.13 1887 5 55 vs 56 > 0. Ahmadzadeh et al., 20 1 ; Sparks et al., 2012 2 ; Bridges and Lake, 2011 3 ; Perry et al., 2012 4 ; Kasimanickam and Whittier, 2013 5 21 22 PREGNANCY RATES AFTER FT Protocol comparison Heifers (N) Pregnancy Rate (%) P-value 7-d CO-Synch + CIDR vs 5-d CO-Synch + CIDR 14-d CIDR- vs 5-d CO-Synch + CIDR 292 1 52 vs 62 0.09 665 2 47 vs 57 0.05 3 3 70 vs 70 > 0. 524 4 53 vs 62 0.13 1887 5 55 vs 56 > 0. Ahmadzadeh et al., 20 1 ; Sparks et al., 2012 2 ; Bridges and Lake, 2011 3 ; Perry et al., 2012 4 ; Kasimanickam and Whittier, 2013 5 23 24 2017 ARSBC, Manhattan, Kan. 4

Heifer Management! Heifers that conceive earlier during their first breeding season! Stay in the herd longer! Produce more pounds of beef over their lifetime Reproductive management prior to the first breeding season # Health platform! Prebreeding evaluation # Target weight! Reproductive tract scores (RTS) # Pelvic measurements # Estrous synchronization # Sire selection (BW or CE EPD) 25 26 Reproductive Tract Scores Reproductive Tract Scores RTS Cycling status Uterine horns Ovaries 1 2 3 4 5 infantile non-cycling > d to puberty non-cycling < d to puberty Estrous cycling Follicular phase Estrous cycling Luteal phase no tone no tone slight tone coiled distended no palpable 8 mm 8- mm > mm corpus luteum present 27 RTS Cycling status Uterine horns Ovaries 1 infantile no tone 2 3 4 5 non-cycling > d to puberty non-cycling < d to puberty Estrous cycling Follicular phase Estrous cycling Luteal phase no tone slight tone coiled distended no palpable 8 mm 8- mm > mm corpus luteum present 28 Heifer Management! RTS: 4 to 6 weeks before breeding or 2 weeks before estrous synchronization! Begin synchronization when 50% of the heifers have RTS of 4 or 5 MISSOURI FIELD DATA SHOW-ME-SELECT TM REPLACEMENT HEIFER PROGRAM 29 2017 ARSBC, Manhattan, Kan. 5

Reproductive Tract Scores and FT 31 Reproductive Tract Scores and FT n = 9,315 32! Show-Me-Select database allows for analysis of FT pregnancy rates based upon reproductive tract score (n=29,343) 1 2 3 4 5 n pregnant 9 255 4,091 5,138 5,088 n exposed 163 893 8,422,092 9,773 FT PR 6% 29% 48% 51% 52% RTS and FT Pregnancy Rate FT Protocol Non-Cycling Cycling 7-Day CO-Synch + CIDR MGA - 14-Day CIDR - 166/438 38% a,x 81/2 35% a,x 4,027/8,647 47% a,y 369/861 43% b,x 265/564 47% b,x 9,588/18,434 52% b,y a,b Percentages within rows with different superscripts differ P < 0.01. x,y Percentages within columns with different superscripts differ P < 0.01. Reproductive Tract Scores and FT n = 19,859 33 Reproductive Tract Scores and FT n = 29,174 heifers 34 RTS and FT Pregnancy Rate FT Protocol Non-Cycling Cycling 7-Day CO-Synch + CIDR MGA - 14-Day CIDR - 166/438 38% a,x 81/2 35% a,x 4,027/8,647 47% a,y 369/861 43% b,x 265/564 47% b,x 9,588/18,434 52% b,y RTS and FT Pregnancy Rate FT Protocol Non-Cycling Cycling Totals 7-Day CO-Synch + CIDR MGA - 14-Day CIDR - 166/438 38% a,x 81/2 35% a,x 4,027/8,647 47% a,y 369/861 43% b,x 265/564 47% b,x 9,588/18,434 52% b,y 535/1,299 41% x 346/794 44% x 13,615/27,081 50% y a,b Percentages within rows with different superscripts differ P < 0.01. a,b Percentages within rows with different superscripts differ P < 0.01. x,y Percentages within columns with different superscripts differ P < 0.01. x,y Percentages within columns with different superscripts differ P < 0.01. 14-DAY CIDR- PROTOCOL FOR HEIFERS 0 14 66 hr TAKE HOME POINTS HEIFERS Combining health & reproduction in a single management step. 35 36 2017 ARSBC, Manhattan, Kan. 6

TAKE HOME POINTS # The protocols work WHAT ABOUT 2-YEAR-OLDS? # Choosing a protocol for FT in heifers # Consider pre-treatment estrous cyclicity status # RTS 4 to 6 weeks before breeding How do short- versus long-term CIDR-based protocols compare? # Protocol compliance will determine success # Product administration # Timing of insemination 37 Abel et al., 2017 38 Treatments 72 hr 0 14 66 hr 0 7 Locations.. Montana Correctional Enterprises Ranch!Deer Lodge, Montana La Cense Montana Ranch!Dillon, Montana MU Thompson Research Center!Spickard, Missouri Abel et al., 2017 39 Abel et al., 2017 40 Estrous Response 14-d CIDR- 7-d CO-Synch + CIDR Proportion % Proportion % Location 1 /19 53 /18 56 Location 2 45/8 42 a 77/5 73 b Location 3 31/4 a 69/6 65 b Location 4 66/124 53 a 3/120 86 b Total 152/355 43 a 259/349 74 b a-b Estrous response rates within rows differ, P < 0.0001 Pregnancy rates after FT 14-d CIDR- 7-d CO-Synch + CIDR Proportion % Proportion % Location 1 14/19 74 /18 56 Location 2 66/8 61 74/5 71 Location 3 65/4 63 57/6 54 Location 4 78/4 63 81/120 68 Total 223/355 63 222/349 64 Abel et al., 2017 41 Abel et al., 2017 42 2017 ARSBC, Manhattan, Kan. 7

Final Pregnancy 14-d CIDR- 7-d CO-Synch + CIDR Pregnancy rate Proportion % Proportion % Pregnancy 223/355 63 222/349 64 Conclusions The 14-d CIDR- and 7-d CO-Synch + CIDR protocols effectively synchronize estrus prior to FT in primiparous twoyear-old postpartum beef cows Implementation of a progestin-based estrus synchronization protocol can increase the proportion of females that conceive early in the breeding season Pregnant within d 8/355 87 7/349 88 Pregnant by end of the breeding season 339/355 95 334/349 96 Photo by Montana Stockgrowers Association Abel et al., 2017 43 Abel et al., 2017 44 FIXED-TIME PROTOCOLS FOR COWS Dealing with Anestrus 45 46 Induction of estrus and ovulation FT Pregnancy rate in Anestrous Cows Progesterone (ng/ml) 6 5 4 3 or 2 CIDR 1 0 15 31 Day 42 2,341 cows 4 Studies Bader et al., 2005 Schafer et al., 2007 Busch et al., 2008 Wilson et al., 20 Estrous Cycling 1329/2341 = 57% Anestrus 12/2341 = 43% 0 90 80 70 60 50 40 20 0 64.8 63.8 Estrous Cycling Anestrus 47 48 2017 ARSBC, Manhattan, Kan. 8

FIXED-TIME FOR COWS 5-AND 7-DAY COMPARISON 5-d CO-Synch + CIDR 7-day CO-Synch + 0 7.. 60-66 hr.. 9 CIDR (5-d)..... 5-day CO-Synch + 8±2 hr 0 5..72 ± 4 hr.. 7 7-d CO-Synch + CIDR CIDR (7-d) 49 Wilson et al., 20; Whittier et al., 2013..... 50 Pregnancy rates resulting from FT in cows Treatment Time of Pregnancy rate On-farm Demonstrations with Fixed-time in Postpartum Beef Cows 7-day CO-Synch + CIDR 5-day CO-Synch + CIDR FT @ 66 hr 140/209 67% FT @ 69 hr 498/906 55% a FT @ 72 hr 140/2 67% FT @ 72 hr 528/911 58% b CIDR (7 d) 0 7...66h Wilson et al., 20; Whittier et al., 2013; a,b P<0.05 # 73 herds # Fixed-time pregnancy rate = 4327/7028 (62%) # 7 herds < 50% 51 52 Pregnancy rates resulting from FT in cows Treatment Time of Pregnancy rate 7-day CO-Synch + CIDR 1 FT @ 66 hr 4327/7028 62 5-day CO-Synch + CIDR 2 FT @ 72 hr 1357/2189 62 1 Patterson et al., 2009 2 Johnson et al., 20 TAKE HOME POINTS Wilson et al., 20; Whittier et al., 2013 # When considering a choice between the 5-d and 7-d protocols. # Both protocols work effectively in postpartum beef cows, with evidence of up to a 3% advantage to the 5-d protocol. # Beef producers must carefully consider the increased labor and treatment costs associated with the 5-d protocol. 53 54 2017 ARSBC, Manhattan, Kan. 9

TAKE HOME POINTS # The protocols work # Choosing a protocol for FT in cows # Cow age # Average number of days postpartum # Body condition CAN HIGHER PREGNANCY RATES BE ACHIEVED WITH SPLIT-TIME? # Protocol compliance will determine success # Product administration # Timing of insemination 55 Thomas et al., 2014 56 CONSIDER FEMALE FERTILITY IN FT ESTRUS AND FEMALE FERTILITY! Among females that exhibit estrus prior to FT! Differences in when females express estrus up to the point of FT! Differing intervals from estrus to ovulation! Among females that don t exhibit estrus prior to FT! induces LH surge within 2 to 4 hr!ovulation will then be induced 24-32 hr after! Estradiol increases prior to estrus! Coordinates physiological processes that contribute to the establishment and maintenance of pregnancy! Cows exhibiting estrus prior to FT have greater serum estradiol concentrations! Higher pregnancy rates are achieved by females that express estrus prior to FT 57 (Perry and Smith, 2015) 58 IS IT WORTH CONSIDERING A MODIFIED APPROACH?! Can male FT fertility be optimized by differentially managing females based on estrus expression prior to FT?! Could fertility be improved by splitting the time for estrous and non-estrous females? SPLIT-TIME TRIALS! Experimental Aim: Development of a strategy that would optimize fertility by better managing females that do not express estrus prior to FT! Hypothesis: Delaying insemination of non-estrous females until 20-24 h after would improve fertility by better aligning the window of sperm fertility with ovulation Thomas et al., 2014 59 Thomas et al., 2014 60 2017 ARSBC, Manhattan, Kan.

SPLIT-TIME TRIALS Thomas et al., 2014 1. Split-time to optimize the use of sex-sorted semen 2. Split-time using conventional semen in heifers ESTRUS DETECTION! ESTROTECT TM estrus detection aids applied at F 2α administration! Activation of estrus detection aid evaluated at time of FT 3. Split-time using conventional semen in cows 61 62 COW PROTOCOLS (7-D CO-SYNCH + CIDR) HEIFER PROTOCOLS (14-D CIDR-) 0 7 66 hr estrous cows Modification for non-estrous cows 0 14 66 hr estrous heifers 0 7 66 hr non-estrous cows 20 hr 11 63 Thomas et al., 2014 Modification for non-estrous heifers 0 14 non-estrous heifers 66 hr 20 hr 64 Thomas et al., 2014 SPLIT-TIME TRIALS Thomas et al., 2014! Split-time increased pregnancy rates by 34% among non-estrous cows inseminated with sex-sorted semen.! Split-time increased pregnancy rates by 15% among non-estrous heifers using conventional semen.! No significant improvement in pregnancy rates were observed with split-time using conventional semen in non-estrous cows. DOES TIMING OF ADMINISTRATION AFFECT ESTROUS RESPONSE AND/OR PREGNANCY RATES FOLLOWING ST? 65 Bishop et al., 2017 66 2017 ARSBC, Manhattan, Kan. 11

WHEN CONSIDERING ST! It is not necessary to administer to heifers or cows that express estrus up to 66 or 90 h after! 14-d CIDR- in heifers! 7-d CO-Synch + CIDR in cows 67 14-d CIDR- with ST (heifers) 0 14 estrous heifers 66 hr 20-24 hr non-estrous heifers remaining heifers! may be administered concurrent with for heifers or cows that fail to express estrus prior to 90 h! Minimizing use of results in a greater overall estrous response in cows Bishop et al., 2017 7-d CO-Synch + CIDR with ST (cows) 0 7 66 hr estrous cows 20-24 hr non-estrous cows remaining cows 68 Bishop et al., 2017 WHERE DO WE GO FROM HERE? WHERE DO WE GO FROM HERE?!RESEARCH!Continued development and evaluation of protocols to expand opportunities to utilize FT or ST in Bos indicus influenced females!development of breeding strategies that facilitate use of sex-sorted semen in beef cows and heifers in conjunction with FT or ST!Begin efforts to elicit differences among bulls on the basis of pregnancy rates resulting from FT 69 70 WHERE DO WE GO FROM HERE?!TECHNOLOGY TRANSFER!Expand efforts to transfer reproductive technologies to the beef industry!applied Reproductive Strategies in Beef Cattle ACKNOWLEDGEMENTS!Emphasize use of these technologies in undergraduate, graduate, and veterinary curricula (internships)!expand linkages with practicing veterinarians 71 72 2017 ARSBC, Manhattan, Kan. 12

ACKNOWLEDGEMENTS ACKNOWLEDGEMENTS! BEEF REPRODUCTION TASK FORCE! BEEF REPRODUCTION LEADERSHIP TEAM 73 74 ACKNOWLEDGEMENTS COOPERATORS # MU FACULTY, STUDENTS, STAFF # MU THOMPSON RESEARCH CENTER # CIRCLE A ANGUS # 4-M RANCH # MFA, INC. # JOHN BARNHART # MASON-KNOX RANCH # OGREN ANGUS # GENEX (STAN LOCK) 75 2017 ARSBC, Manhattan, Kan. THANK YOU 76 13