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

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1 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 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) ARSBC, Manhattan, Kan. 6 1

2 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 HEIFERS FIXED-TIME.. 54 ± 2 hr.. 9 Long-term Protocols 14-day d 66 ± 2 hr 33 5-day CO-Synch + MGA - 8±2 hr ± 4 hr.. 7 MGA d ± 2 hr 36 9 HOW DO LONG-TERM PROTOCOLS COMPARE IN HEIFERS? MGA days Heat detection and CIDR days 36 Heat detection and 11 Mallory, et al., ARSBC, Manhattan, Kan. 2

3 DISTRIBUTION OF ESTRUS AFTER MGA OR CIDR Estrus, % MGA NR Interval after progestin removal, treatment d DISTRIBUTION OF ESTRUS AFTER 45 MGA day CIDR Estrus, % day CIDR- Estrus, % NR NR Interval after progestin removal, treatment d 13 Interval after administration, h 14 MGA- VS 14-DAY CIDR- MGA hr 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) CIDR (7 d) CIDR (7 d) THE MULTI-STATE CIDR TRIAL h Detect estrus & h Detect estrus & Lamb et al., 2006 CIDR (7 d) CIDR (7 d) h FT h FT 17 Lamb et al., ARSBC, Manhattan, Kan. 3

4 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., DAY CO-SYNCH + CIDR PREGNANCY RATES AFTER FT 5-d CO-Synch + CIDR FT at 60 h CIDR (5-d)..8 ± 2 h ± 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 vs vs vs 70 > vs vs 56 > 0. Ahmadzadeh et al., 20 1 ; Sparks et al., ; Bridges and Lake, ; Perry et al., ; Kasimanickam and Whittier, 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 vs vs vs 70 > vs vs 56 > 0. Ahmadzadeh et al., 20 1 ; Sparks et al., ; Bridges and Lake, ; Perry et al., ; Kasimanickam and Whittier, ARSBC, Manhattan, Kan. 4

5 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) Reproductive Tract Scores Reproductive Tract Scores RTS Cycling status Uterine horns Ovaries 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 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 ARSBC, Manhattan, Kan. 5

6 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) n pregnant ,091 5,138 5,088 n exposed ,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 < x,y Percentages within columns with different superscripts differ P < Reproductive Tract Scores and FT n = 19, 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 < a,b Percentages within rows with different superscripts differ P < x,y Percentages within columns with different superscripts differ P < x,y Percentages within columns with different superscripts differ P < DAY CIDR- PROTOCOL FOR HEIFERS hr TAKE HOME POINTS HEIFERS Combining health & reproduction in a single management step ARSBC, Manhattan, Kan. 6

7 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., Treatments 72 hr 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., Abel et al., 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/ a 3/ b Total 152/ a 259/ b a-b Estrous response rates within rows differ, P < Pregnancy rates after FT 14-d CIDR- 7-d CO-Synch + CIDR Proportion % Proportion % Location 1 14/19 74 /18 56 Location 2 66/ /5 71 Location 3 65/ /6 54 Location 4 78/ / Total 223/ / Abel et al., Abel et al., ARSBC, Manhattan, Kan. 7

8 Final Pregnancy 14-d CIDR- 7-d CO-Synch + CIDR Pregnancy rate Proportion % Proportion % Pregnancy 223/ / 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/ / Pregnant by end of the breeding season 339/ / Photo by Montana Stockgrowers Association Abel et al., Abel et al., FIXED-TIME PROTOCOLS FOR COWS Dealing with Anestrus Induction of estrus and ovulation FT Pregnancy rate in Anestrous Cows Progesterone (ng/ml) or 2 CIDR 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% Estrous Cycling Anestrus ARSBC, Manhattan, Kan. 8

9 FIXED-TIME FOR COWS 5-AND 7-DAY COMPARISON 5-d CO-Synch + CIDR 7-day CO-Synch hr.. 9 CIDR (5-d) day CO-Synch + 8±2 hr ± 4 hr d CO-Synch + CIDR CIDR (7-d) 49 Wilson et al., 20; Whittier et al., 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 66 hr 140/209 67% 69 hr 498/906 55% a 72 hr 140/2 67% 72 hr 528/911 58% b CIDR (7 d) h 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% Pregnancy rates resulting from FT in cows Treatment Time of Pregnancy rate 7-day CO-Synch + CIDR 1 66 hr 4327/ day CO-Synch + CIDR 2 72 hr 1357/ Patterson et al., 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 ARSBC, Manhattan, Kan. 9

10 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., 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 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 h after would improve fertility by better aligning the window of sperm fertility with ovulation Thomas et al., Thomas et al., ARSBC, Manhattan, Kan.

11 SPLIT-TIME TRIALS Thomas et al., 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 COW PROTOCOLS (7-D CO-SYNCH + CIDR) HEIFER PROTOCOLS (14-D CIDR-) hr estrous cows Modification for non-estrous cows hr estrous heifers hr non-estrous cows 20 hr 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., ARSBC, Manhattan, Kan. 11

12 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 d CIDR- with ST (heifers) 0 14 estrous heifers 66 hr 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., d CO-Synch + CIDR with ST (cows) hr estrous cows 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 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 ARSBC, Manhattan, Kan. 12

13 ACKNOWLEDGEMENTS ACKNOWLEDGEMENTS! BEEF REPRODUCTION TASK FORCE! BEEF REPRODUCTION LEADERSHIP TEAM 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) ARSBC, Manhattan, Kan. THANK YOU 76 13