Maximize Female Genetic Potential

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1 How do you gain genetics? Maximize Female Genetic Potential Shantille Kruse, Ph.D., Boviteq and Todd Bilby, Ph.D., Merck Animal Health Gene$c gain is the amount of increase in performance that is achieved through ar$ficial gene$c improvement programs. Gene$c Gain = Accuracy x gene$c varia$on x intensity genera$onal interval Resources to maximize genetic potential Transfer (1970 s) Sexed Semen (2000 s) Genomics (2000 s) Dairy replacement heifer strategy Precision Breeding (gene editing) Genetics Reverse Sorted Semen AI (1950 s ) Cloning (2000 s) In Vitro Fertilizatio n (1990 s) (Hoffman and Marti, 2013) 2016 Angus University, Indianapolis, Ind. 1

2 Half-sib embryo variation for CEM There is significant varia$on even between ca?le that are closely related Genetic variation in sibling embryos Maternal CED BW WW YW RFI DMI YH SC DOC HP CEM Milk MW MH CW Marb RE FAT Tend Paternal Dam A Bull A Dam A Bull A Dam A Bull A Dam A Bull A Dam A Bull A Dam A Bull A Dam A Bull A Dam A Bull A Genomic variation in Calving Ease Maternal among half-sibling embryos (percentile rankings in Angus breed) all sired by a single high $B Angus bull CED BW WW % 82% 46% CW 4 22% Genomic-Enhanced Rate of genetic gain comparing GE- to. Accuracy values, standard deviations and EPD baseline heifer pregnancy data in the calculations derived from AAA data. This example is applicable to any breed and shows the advantage of GE- over alone. GE-: Greater selection accuracy Select and breed best young bulls and cows Faster progress Growth and Carcass Maternal GE- Screen and select What is your time worth? Birth Year 1 Year 2 Year 3 Year 4 Year 5 Screen gender, defects, parentage or profile ET the best embryos Bull calf weight Collect DNA Samples on bull calves and heifers Get GE-! Confirm calf parentage Get GE-! Yearling weight Mate bull for progeny testing Mate bull for maternal Birth weight of progeny Wean and place progeny on feed Birth of progeny Wean and sort heifers Market yearling bulls with accurate GE- Keep heifers with the best GE- Produce more top bulls on fewer cows Keep best cow lines Get Growth Breed heifers for first calf Slaughter progeny. Get Carcass Rebreed heifers for second calf Get Maternal 2016 Angus University, Indianapolis, Ind. 2

3 Parent ages for marketed Holstein bulls Global IVF Production In Vivo vs IVF Production In 2014, IVF embryos represented 49% of global embryo production What is IVF? In Vitro Fertilization In Vitro = in glass First live calf born to IVF/ procedure developed 1987, 1988 Technique originally developed as a research tool and for use in only extremely valuable donors or terminal situations In 2015, IVF represented: 50%+ embryos globally 41% of U.S. embryos 2016 Angus University, Indianapolis, Ind. 3

4 What is OPU? Oocyte/ovum pick up Oocyte = female gamete/egg Transvaginal ultrasound guided aspiration Number and quality of oocytes is the rate limiting factor in developing embryos Benefits of IVF Greater time frame to work with elite donors Prepubertal animals as young as 7 months of age Pregnant donors Can be collected every 2 weeks 93% of donors will successfully create embryos versus 75-80% with ET Donors with oviduct/cl issues In vitro vs. in vivo embryo production Number of (60 d) Method of embryo production In vitro In vivo Collections 4 1 Ova collected 38 (mean 9.5) 7.3 (mean 7.3) Viable embryos 18.8 (mean 4.7) 4.3 (mean 4.3) Pregnancy rate (d 30) 4.2 (59.1%) 1.3 (61.0%) Pregnancy rate (d 60) 3.8 (53.4%) 1.2 (59.4%) Benefits of IVF Fertilization rates are similar between conventional, sexed, or reverse sorted semen Semen testing can be performed to determine if a particular semen lot work well in IVF Gender selection is easier, more efficient Make more efficient use of valuable semen Simpler process for the owner; no need to heat detect or breed donors s more likely to result in pregnancy in times of stress Adapted from Bousquet et al., Angus University, Indianapolis, Ind. 4

5 Cost Comparison: In Vivo vs. IVF Drawbacks of IVF Aspiration and oocyte searching should occur in a heated collection area Number of vets trained to do OPU is limited Bull-to-bull variation More expensive and logistically more complicated than conventional flush Item In Vivo IVF Collection $ per donor $ per donor Stimulation drugs $ per donor $ per donor IVF N/A $ per donor freezing $40-50 per embryo $40-55 per embryo transfer $50-75 per embryo $50-75 per embryo Total Cost per Donor $ $ Average # embryos per collection Cost per Frozen $93 $160 Comparison: In Vivo vs. IVF Parameter Superovulation IVF Collection frequency Every 4-6 weeks Every 2 weeks Semen utilization Sexed semen Multiple straws per donor Reduced embryo production Multiple donors with 1-2 straws Similar embryo production Reverse sorting N/A Can be performed Prepubertal donors N/A Can be performed Pregnant donors N/A Can be performed Getting Started Select the right donors to achieve the goals of your operation Genetically superior Antral follicle counts Think about costs per pregnancy Utilize satellite centers/ haul in facilities Do enough animals to get a valid test of the hypothesis Select bulls that perform well in IVF when possible Set up donors properly 2016 Angus University, Indianapolis, Ind. 5

6 Donor Preparation Donor preparation Consequences of OPU on natural cycles Ovulation Benefits of superovulation Competence window (Higher embryo production) Competence window (Higher embryo production) Follicle diameter Atresia Oocyte competence Follicle diameter Homogenous population of competent oocytes Oocyte competence Cycle day Cycle day Ovum Pick-Up Ovum Pick-Up Ovum Pick-Up Ovum Pick-Up DFR + CIDR FSH Ovum Pick-Up Strategies for Angus Breeders What to Expect Seedstock contracts Showstock Maximize number of offspring per year out of valuable donor Genomic testing to ID best carcass animals; retain ownership and sell on grid Donor pooling Bull selection is key Type OPUs Avg # Oocytes Beef AETA Beef Boviteq Angus- Boviteq Avg # % Viable s Dev 15, % 2, % 1, % 2016 Angus University, Indianapolis, Ind. 6

7 Pitfalls Selecting low potential donors Shot compliance 12 h intervals Consider herd health, BCS, nutrition, free choice mineral, avoid cottonseed & high CP Important to both donor and recipient Bull selection; RS = Sexed Not all labs are created equal Not everything will be freezable, recipient options Freezing technique direct transfer Calving induce by due date Pregnancy Success at d60 Beef: Fresh, n = 8343, % Pregnant = 52.4% QI, n = 3475, % Pregnant = 62.2% Frozen, n = 1466, % Pregnant = 61.5% Large Calf Syndrome Issue was linked to use of fetal calf serum and oviductal co-culture in early IVP systems Our experience at Boviteq: 512 Holstein calvings in Mean weight at birth : 91 lbs (14 calves >120 lbs) Died at calving: < 4% Died before weaning: < 2% Thank you! Future Developments! Donors and bulls will continue to get younger! development rates and pregnancy rates to IVF embryos will increase! Increased access for producers to OPU/IVF! Likely to surpass ET as preferred assisted reproductive technology in U.S Angus University, Indianapolis, Ind. 7

8 Genotyping Wide variation between sib embryos Selection decision at -9 months of age Recipient cow cost savings Thank You Screen and implant the best genetics Save years in generational interval 2016 Angus University, Indianapolis, Ind. 8