Estrus Synchronization Protocols for Cows Cliff Lamb University of Florida Applied Reproductive Strategies in Beef Cattle NCBA Convention January 28, 2010 Estrous Synchronization Protocols Hybrid Synch MGA/ Two shot 7-11 Synch Select Synch MGA Select Hybrid Synch+ Presynch Resynch One shot CO-synch Ov-synch / US Beef Semen Sales and Custom Collected Semen 4 x 10 6 units CO-synch+ Heat Synch http://www.naab-css.org/sales/table_list.html
US Beef Cow Inventory Percentage of Semen Sold and Collected Compared to Beef Cow Inventory 11% http://www.nass.usda.gov Definitions!Synchronization Rate: % of females detected in estrus compared to total number synchronized.!conception Rate: % of females pregnant compared to number of females inseminated.!pregnancy Rate: % of females pregnant compared to total number synchronized. 2! Prostaglandin ( 2! ) System Select Synch Heat detect Heat detect -14 0 144-7 0 144 Days from Hours from Days from Hours from
Ovsynch AI -7 0 48 60-66 Days from Hours from -7 0 48 Days from Hours from Select Synch & TAI 2! 2! vs. Select Synch Heat detect 2! 2! Heat detect -7 0 72-84 Days from Hours from Select Synch Heat detect (Stevenson et al., 2000) 2! 2! vs. Select Synch Select Synch vs. Item 2! 2! Select Synch No. of Cows 294 289 Select Synch Heat detect Synchronization rate, % 142/294 (48) 175/289 (61) Conception rates, % 86/142 (61) 115/175 (66) Pregnancy rates, % 86/294 (28) 115/289 (38) (Stevenson et al., 2000) (Grieger et al., 2001)
Select Synch vs. vs. Ovsynch Item Select Synch No. of Cows 237 223 Synchronization rate, % 130/237 (55) - Conception rates, % 93/130 (72) 106/223 (48) Pregnancy rates, % 93/237 (39) 106/223 (48) Ovsynch AI -7 0 48 72 Days relative to Hours relative to (Grieger et al., 2001) (Geary et al., 2001) vs. Ovsynch CO-synch vs. CO-synch+ + -7 0 48 Days relative to Hours relative to (Geary et al., 2001) (Lamb et al., 2001) First Service Pregnancy Rates Effect of BCS on Pregnancy Rates Treatments (Lamb et al., 2001) Body condition score (Lamb et al., 2001)
Effect of Location on Pregnancy Rates -PG & TAI Detect estrus + Select Synch & TAI Detect estrus Select Synch+ & TAI Detect estrus -18 to -16-7 0 60 84 Locations B B Days relative to Hours relative to (Larson et al., 2006) Pregnancy Rates after Estrus Detection Alone vs TAI 5-day + 53 43 54 53 58 a b c a,b b -5 d 0 8±2h 72h P < 0.05 Treatment (Larson et al., 2006) (Day et al., 2008) 7-day + 5-day + -7 d 0 60-66h -5 d 0 8±2h 72h
7-day + Distribution of Estrus for 5-day and 7-day + protocols -7 d 0 60-66h 5-day + -5 d 0 8±2h 72h (Wilson et al., 2010) Pregnancy rate to 7-day + protocol Pregnancy rate to 5-day + protocol n > 7,000 n > 2,600 n > 2.100 n > 2,000 Effects of a fixed-time AI system on calving distribution Calving Distribution of Cows Calving after TAI or Bull breeding Control n = 285 Natural mating 44.1% vs. 24.7% TAI + TAI n = 263 Natural mating (Rodgers, 2007) (Rodgers, 2007)
Calving Distribution after Synchronization of Estrous Does the use of the + Protocol delay return to estrus? 438 suckled cows were estrous synchronized using the 7-day + Protocol. (Larson et al., 2006) (Mercadante et al., 2010) Calving Distribution Estrus response of cows following the 7-day + protocol n=275?? 90% Overall pregnancy rate n=85 n=37 n=34 97.5% return to estrus rate!! Average Interval to estrus = 20.9 days (Mercadante et al., 2010) (Mercadante et al., 2010) Acknowledgements People Dr. Carl Dahlen Dr. Jamie Larson Mr. Guilherme Marquezini Dr. Jeff Stevenson Graduate Students Technical staff Support staff Collaborators Co-authors Beef cattle producers Funding and Product Support ABS Global, Inc. Blandin Foundation Intervet Animal Health IVX/Teva Animal Health Merial Animal Health MN-AURI NAAB Pfizer Animal Health Select Sires, Inc. U of FL U of MN USDA-CSREES
Thank You! Contact Information: Cliff Lamb University of Florida 3925 HWY 71 Marianna, FL 32446 Tel: 850-394-9124 Email: gclamb@ufl.edu