ARSBC 2016, Des Moines, IA 1

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1 CONTROL OF ESTRUS AND OVULATION IN BEEF HEIFERS AND COWS The next minutes..! Management considerations related to FT " Heifers and Cows! Overview of protocols " Heifers and Cows! Questions and discussion - later DJ Patterson, JM Thomas, BE Bishop, JM Abel, JWC Locke, and MF Smith Division of Animal Sciences University of Missouri MANAGEMENT CONSIDERATIONS RELATED TO ESTRUS SYNCHRONIZATION & FIXED-TIME DO WE KNOW WHAT TO EXPECT AT CALVING FROM COWS THAT CONCEIVE ON THE SAME DAY TO THE SAME SIRE? Location 1; Sire A (Angus) BW EPD -.3; CED = Range 71-9 Mean = Location ; Sire D (Red 18 Angus) BW EPD +.3; CED = - Range 73-3 Mean = Location 1; Sire B (Angus) Location 1; Sire C (Angus) BW EPD +3.5; CED = +6 BW EPD -1.1; CED = Range 75-9 Mean = Range 7-87 Mean = Location 3; Sire B (Angus) Location ; Sire B (Angus) 18 BW EPD +3.5; CED = BW EPD +3.5; CED = +6 Range 7-9 Mean = 83 Range 75-9 Mean = CONSIDER THE IMPACT OF ESTRUS SYNCHRONIZATION ON CALVING DISTRIBUTION ARSBC 16, Des Moines, IA 1

2 HUGHES, 5! Increased profits! Moving later calving cows forward toward the first and second calving intervals! High production herds! 61% of the calves born by day 1! 85% by day! 9% by day 63 % CALVING DISTRIBUTION FOR ENTIRE CALVING SEASON Cumulative Calf % by: day 15 = 65% day 1 = 7% day 3 = 8% day = 93% Day of calving season years; 11 herds; 1511 calves 1 9 CUMULATIVE CALF CROPS FIRST 6 DAYS OVER 1 CALVING SEASONS MU THOMPSON RESEARCH CENTER UNIVERSITY OF FLORIDA - NFREC LAMB ET AL., 15 Percentage Day of calving season NATURAL SERVICE (3 YEARS; N = 56) ESTRUS DETECTION & (5 YEARS; N = 1) FIXED-TIME ( YEARS; N = 766) CHANGE IN CALF VALUE YEAR MEAN CALVING DAY DIFFERENCE FROM 6/7 PER CALF INCREASE IN VALUE HERD INCREASE IN VALUE $87 $99 $19 $135 $166 $169 $19,1 $9,7 $3,7 $,5 $9,8 $5,7 CONSIDERATIONS RELATED TO HEIFER MANAGEMENT HEIFER MANAGEMENT! Heifers that conceive earlier during their first breeding season! Stay in the herd longer! Produce more pounds of beef over their lifetime ARSBC 16, Des Moines, IA

3 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 RTS Cycling status Uterine horns Ovaries infantile > 3 d to puberty < 3 d to puberty Follicular phase Luteal phase no tone no tone slight tone coiled distended no palpable 8 mm 8-1 mm > 1 mm corpus luteum present REPRODUCTIVE TRACT SCORES REPRODUCTIVE TRACT SCORES RTS Cycling status Uterine horns Ovaries 1 infantile no tone 3 5 > 3 d to puberty < 3 d to puberty Follicular phase Luteal phase no tone slight tone coiled distended no palpable 8 mm 8-1 mm > 1 mm corpus luteum present RTS Cycling status Uterine horns Ovaries 1 infantile no tone 3 5 > 3 d to puberty < 3 d to puberty Follicular phase Luteal phase no tone slight tone coiled distended no palpable 8 mm 8-1 mm > 1 mm corpus luteum present REPRODUCTIVE TRACT SCORES RTS Cycling status Uterine horns Ovaries 1 infantile no tone 3 5 > 3 d to puberty < 3 d to puberty Follicular phase Luteal phase no tone slight tone coiled distended no palpable 8 mm 8-1 mm > 1 mm corpus luteum present Endocrine and Ovarian Changes Associated with Puberty Onset Estradiol secretion Estradiol feedback LH secretion Follicle diameter Prepubertal Peripubertal Pubertal Reproductive tract score ARSBC 16, Des Moines, IA 3

4 HEIFER MANAGEMENT! RTS: to 6 weeks before breeding or weeks before estrous synchronization MGA-BASED PROTOCOLS FOR HEIFERS! Begin synchronization when 5% of the heifers have RTS of or 5 SHORT-TERM MGA PROGRAM STAGE OF CYCLE EFFECT ON CONCEPTION RATE 7-DAY MGA- TREATMENT 1 86 MGA (7 days) 7 Treatment days Estrus (less fertile) Conception rate (%) d 1-5 d 6-11 d 1-16 d 17-1 Day of estrous cycle at beginning of MGA feeding Moody et al., 1978; Patterson et al., 1986 Patterson et al., 1986 MGA- MGA- was the preferred method of estrus synchronization in beef heifers (Brown et al., 1986; Deutscher et al., ; Lamb et al., ). MGA to 19 days Treatment day 33 MGA (1 days) Sub-fertile estrus Treatment days Natural service ARSBC 16, Des Moines, IA

5 MGA PRIOR TO NATURAL SERVICE OR MGA- PRIOR TO Breeding program Natural service No. heifers Estrous response Synchronized conception rate Synchronized pregnancy rate /179 66% % of herd in estrus 5 335/5 79% 1/335 7% 1/5 57% MGA- () MGA (Natural service) FIXED-TIME PROTOCOLS FOR HEIFERS MGA- PROTOCOL FOR HEIFERS HOW DO LONG-TERM PROTOCOLS COMPARE IN HEIFERS? MGA 17 to 19 days Treatment day Brown et al., 1986; Deutscher et al., ; Lamb et al., ARSBC 16, Des Moines, IA 5

6 1-DAY CIDR- PROTOCOL FOR HEIFERS CIDR hr Treatment day MGA 1 1 CIDR 1 19 days 16 days Heat detection and 3 36 Heat detection and Mallory et al., 11 Mallory, et al., 9 ESTRUS DISTRIBUTION AFTER MGA OR CIDR Estrus, % MGA NR Interval after progestin removal, treatment d DISTRIBUTION OF ESTRUS AFTER 5 MGA day CIDR Estrus, % day CIDR- Estrus, % NR NR Interval after progestin removal, treatment d Interval after administration, h MGA- VS 1-DAY CIDR- " Insemination performed on the basis of observed estrus " No differences in synchronized conception or pregnancy rates (Mallory et al., 9) " FT " No differences in pregnancy rates (Vraspir et al., 13) THE MULTI-STATE CIDR TRIAL Lamb et al., 6 ARSBC 16, Des Moines, IA 6

7 CIDR (7 d) 7..8 h Detect estrus & CIDR (7 d) h Detect estrus & MULTI-STATE CIDR TRIAL " at CIDR insertion did not improve pregnancy rates after FT CIDR (7 d) h FT CIDR (7 d) h FT " at CIDR insertion did not alter the percentage of heifers detected in estrus or the distribution of estrus after " A combination of detecting estrus and before cleanup enhanced pregnancy rates over FT Lamb et al., 6 Lamb et al., 6 5-DAY CO-SYNCH + CIDR 5-DAY CO-SYNCH + CIDR 5-d CO-Synch + CIDR FT at 6 h CIDR (5-d)..8 ± h ± h PREGNANCY RATES AFTER FT Protocol comparison Heifers (N) Pregnancy rate (%) P-value 7-day CO-Synch + CIDR vs 5-day CO-Synch + CIDR 1-day CIDR- vs 5-day CO-Synch + CIDR vs vs vs 7 > vs vs 56 >.1 Ahmadzadeh et al., 1 1 ; Sparks et al., 1 ; Bridges and Lake, 11 3 ; Perry et al., 1 ; Kasimanickam and Whittier, 13 5 PREGNANCY RATES AFTER FT Protocol comparison Heifers (N) Pregnancy Rate (%) P-value 7-d CO-Synch + CIDR vs 5-d CO-Synch + CIDR 1-d CIDR- vs 5-d CO-Synch + CIDR vs vs vs 7 > vs vs 56 >.1 Ahmadzadeh et al., 1 1 ; Sparks et al., 1 ; Bridges and Lake, 11 3 ; Perry et al., 1 ; Kasimanickam and Whittier, 13 5 ARSBC 16, Des Moines, IA 7

8 MISSOURI FIELD DATA SHOW-ME-SELECT TM REPLACEMENT HEIFER PROGRAM SHOW-ME-SELECT REPLACEMENT HEIFER PROGRAM A summary of RTS and FT pregnancy rate for 3,81 heifers evaluated from Spring 1 - Fall 15 RTS n pregnant n exposed FT PR 6% 9% 7% 5% 5% SHOW-ME-SELECT REPLACEMENT HEIFER PROGRAM SHOW-ME-SELECT REPLACEMENT HEIFER PROGRAM RTS and FT Pregnancy Rate (n = 7,) FT Protocol Non-Cycling Cycling 7-Day CO-Synch + CIDR MGA - 1-Day CIDR - 11/333 36% a,x 81/3 35% a,x 3118/6839 6% a,y a,b Percentages within rows with different superscripts differ P <.1. 35/689 % b,x 65/56 7% b,x 7583/168 5% b,y x,y Percentages within columns with different superscripts differ P <.1. RTS and FT Pregnancy Rate (15,937 heifers) FT Protocol Non-Cycling Cycling 7-Day CO-Synch + CIDR MGA - 1-Day CIDR - 11/333 36% a,x 81/3 35% a,x 3118/6839 5% a,y a,b Percentages within rows with different superscripts differ P <.1. 35/689 % b,x 65/56 7% b,x 7583/168 5% b,y x,y Percentages within columns with different superscripts differ P <.1. 1-DAY CIDR- PROTOCOL FOR HEIFERS CIDR hr Treatment day TAKE HOME POINTS HEIFERS Combining health & reproduction in a single management step. ARSBC 16, Des Moines, IA 8

9 TAKE HOME POINTS " The protocols work " Choosing a protocol for FT in heifers " Consider pre-treatment estrous cyclicity status " RTS to 6 weeks before breeding FIXED-TIME PROTOCOLS FOR COWS " Protocol compliance will determine success " Product administration " Timing of insemination FIXED-TIME FOR COWS 5-AND 7-DAY COMPARISON 5-d CO-Synch + CIDR 7-day CO-Synch + CIDR CIDR hr.. 9 CIDR (5-d) day CO-Synch + CIDR CIDR 8± hr 5..7 ± hr d CO-Synch + CIDR CIDR (7-d) Wilson et al., 1; Whittier et al., Pregnancy rates resulting from FT in cows Treatment Time of Pregnancy rate 66 hr 1/9 67% 7-day CO-Synch + CIDR 69 hr 98/96 55% a Pregnancy rates resulting from FT in cows Treatment Time of Pregnancy rate 7-day CO-Synch + CIDR 1 66 hr 37/ day CO-Synch + CIDR 7 hr 1/1 67% 7 hr 58/911 58% b 5-day CO-Synch + CIDR 7 hr 1357/ Patterson et al., 9 Johnson et al., 1 Wilson et al., 1; Whittier et al., 13; a,b P<.5 ARSBC 16, Des Moines, IA 9

10 TAKE HOME POINTS Wilson et al., 1; Whittier et al., 13 " 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. TAKE HOME POINTS " The protocols work " Choosing a protocol for FT in cows " Cow age " Average number of days postpartum " Body condition " Protocol compliance will determine success " Product administration " Timing of insemination Mil. Head 6. HEIFER REPLACEMENTS WHAT ABOUT -YEAR-OLDS? Data Source: USDA-NASS Livestock Marketing Information Center Courtesy of Dr. Scott Brown July 1 - U.S., Annual C-N-37 7/8/15 Abel et al., 16 BACKGROUND Management of primiparous two-year-old cows presents a unique challenge in managing a beef herd!increased incidence of dystocia!greater nutrient demands!longer postpartum intervals!reduced fertility Photo by Montana Stockgrowers Association CONSIDERATIONS FOR YOUNG COWS Heifers and primiparous two-year-old cows are often maintained as a separate management group!estrus synchronization and most widely used in heifers!opportunity to use management strategies specifically for young cows Estrus synchronization protocols have not been evaluated exclusively in primiparous two-year-old cows ARSBC 16, Des Moines, IA 1

11 EXPERIMENTAL OBJECTIVES TREATMENTS (N = 7; -YR-OLDS) Experimental Goal: Evaluate short- and long-term CIDR-based protocols in primiparous -year olds on the basis of estrous response prior to and pregnancy rates resulting from FT Hypothesis:!Because of extended postpartum intervals in primiparous two-year-old beef cows, long- vs short-term treatment with progesterone may provide the opportunity to improve estrous cyclicity and resulting pregnancy rates following FT Abel et al., 16 Abel et al., 16 EXPERIMENTAL OVERVIEW BREEDING SEASON OVERVIEW Locations MU Thompson Research Center La Cense Ranch, Dillon, MT MT Correctional Enterprises, Deer Lodge, MT 1-d CIDR- 7-d CO-Synch + CIDR Proportion % Proportion % Estrous response 15/355 3 a 59/39 7 b Pregnancy 3/ /39 6 Treatment n BCS DPP Totals 1-d CIDR ±. 78. ±.6 7-d CO-Synch + CIDR ± ±.6 Pregnant within 3 d Pregnant by end of the breeding season a,b Percentages with differenct superscripts differ P <.1. 38/ / / /39 96 Abel et al., 16 Abel et al., 16 CONCLUSIONS Estrous response at FT was higher for 7-d CO-Synch + CIDR compared to 1-d CIDR- treated cows Pregnancy rates resulting from FT were similar Implementation of a progestin-based estrus synchronization protocol can increase the proportion of females that conceive early in the breeding season CAN HIGHER PREGNANCY RATES BE ACHIEVED WITH SPLIT-TIME? 1-d CIDR- 7-d CO-Synch + CIDR Proportion % Proportion % Estrous Response 15/355 3 a 59/39 7 b Pregnancy Rate 3/ /39 6 Abel et al., 16 Thomas et al., 1 ARSBC 16, Des Moines, IA 11

12 CONCEPTUALIZING FEMALE FERTILITY IN FT LH Consider a synchronized estrus Estrus Differing intervals from estrus to ovulation Differences in when females express estrus during the synchronized period 8 h interval from LH to ovulation Time relative to ovulation (h) X Thomas et al., 1 ESTRUS AND FEMALE FERTILITY! 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 (Perry and Smith, 15) IS IT WORTH CONSIDERING A MODIFIED APPROACH TO FT?! 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., 1 Thomas et al., 1 SPLIT-TIME TRIALS Thomas et al., 1 ESTRUS DETECTION 1. Split-time to optimize the use of sex-sorted semen. Split-time using conventional semen in heifers! ESTROTECT TM estrus detection aids applied at F α administration! Activation of estrus detection aid evaluated at time of FT 3. Split-time using conventional semen in cows ARSBC 16, Des Moines, IA 1

13 COW PROTOCOLS Thomas et al., 1 HEIFER PROTOCOLS Thomas et al., 1 7-Day CO-Synch + CIDR CIDR 66 hr d CIDR- (Heifers) CIDR 66 hr Modification for non-estrous cows CIDR 66 hr hr Modification for non-estrous heifers CIDR 66 hr hr SPLIT-TIME TRIALS Thomas et al., 1! Split-time increased pregnancy rates by 3% 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? Bishop et al., 15 CURRENT ST PROTOCOLS Bishop et al., 15 1-d CIDR- protocol for heifers with ST CONCLUSIONS WHEN CONSIDERING ST! It is not necessary to administer to heifers or cows that express estrus up to 66 or 9 h after! 1-d CIDR- in heifers! 7-d CO-Synch + CIDR in cows 7-d CO-Synch + CIDR protocol for cows with ST! may be administered concurrent with for heifers or cows that fail to express estrus prior to 9 h! Minimizing use results in a greater overall estrous response in cows Bishop et al., 15 ARSBC 16, Des Moines, IA 13

14 WHERE DO WE GO FROM HERE? BEEF SEMEN SALES 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 16, Des Moines, IA 1

15 ACKNOWLEDGEMENTS ACKNOWLEDGEMENTS! BEEF REPRODUCTION TASK FORCE! BEEF REPRODUCTION LEADERSHIP TEAM ACKNOWLEDGEMENTS ACKNOWLEDGEMENTS ZOETIS MERIAL BAYER ESTROTECT SEXING TECHNOLOGIES ABS GLOBAL ACCLERATED GENETICS GENEX SELECT SIRES, INC. COOPERATORS " MU FACULTY, STUDENTS, STAFF " MU THOMPSON RESEARCH CENTER " CIRCLE A ANGUS " -M RANCH " MFA, INC. " JOHN BARNHART " MASON-KNOX RANCH " OGREN ANGUS " GENEX (STAN LOCK) THANK YOU ARSBC 16, Des Moines, IA 15