H. Duane Norman Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD Dairy Cattle Reproductive Council Convention (1) 2007 Genetic selection for reproduction: Current reproductive status of the national herd; Application of selection indexes for dairy producers

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (2) H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (2) Current reproductive status of the national herd

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (3) Bull fertility l Estimated Relative Conception Rate (ERCR) w 70-day nonreturn rate (NRR) w Phenotypic evaluation w Source: − DRMS (Raleigh, NC), 1986−2005 − USDA (Beltsville, MD), 2006−present l Western Bull Fertility Analysis w 75-d veterinary-confirmed conception rate w Source: AgriTech (Visalia, CA), 2003 −present

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (4) ERCR distribution (Aug. 2007)

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (5) Survey of AI organizations l Does your organization rate bulls on fertility from field data? l Where do you obtain the data you use to evaluate them? l How long a time period is included in your evaluation? l What do you publish? l How many nonreturn days are in your calculation? l Is your evaluation derived from first or all services? l Do you eliminate cows sold before a specific number of days after insemination? l Do you eliminate cows in herds that go off test before a specific number of days after insemination? l Is information on services from natural service bulls that follow AI breedings available to you to document failures of those AI breedings?

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (6) Survey results l All had programs to monitor bull fertility, but few relied completely on in-house information w Most received some information from technician breedings w One purchased breeding records from a dairy records processing center w Another obtained breeding records directly from cooperating herds l Most common fertility measure was NRR w Varied from 59 to 90 days for first breeding w Some organizations used a range of days

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (7) Survey results (cont.) l Conception rate (CR) used by one because of availability of pregnancy-check records l Time period for data included in a bull’s fertility evaluation varied from 1 year to no limit l Equal number included only first services compared with all services l Data from technician breedings w Not adjusted for cow departures because of culling or when a herd discontinued production testing w No access to data that showed when natural service followed an AI mating

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (8) New USDA service sire evaluation l Based on conception rate rather than NRR l More accurate w Inseminations from most of the United States w All services (not just first) w Additional model effects included l Available early 2008 l Documentation at ftp://aipl.arsusda.gov/pub/outgoing/BullFert/

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (9) Cow fertility trends Year bred Calving to 1st breeding (d) 70-d NRR for 1st service (%) 1st service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (10) Cow fertility trends Year bred Calving to 1st breeding (d) 70-d NRR for 1st service (%) 1st service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey ……

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (11) Cow fertility trends Year bred Calving to 1st breeding (d) 70-d NRR for 1st service (%) 1st service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey …………

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (12) Cow fertility trends Year bred Calving to 1st breeding (d) 70-d NRR for 1st service (%) 1st service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey ………………

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (13) Parity averages (2005 breedings) Parity Calving to 1st breeding (d) 70-day NRR for 1st service (%) 1st-service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey >59288

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (14) Parity averages (2005 breedings) Parity Calving to 1st breeding (d) 70-day NRR for 1st service (%) 1st-service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey >

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (15) Parity averages (2005 breedings) Parity Calving to 1st breeding (d) 70-day NRR for 1st service (%) 1st-service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey >

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (16) Parity averages (2005 breedings) Parity Calving to 1st breeding (d) 70-day NRR for 1st service (%) 1st-service CR (%) Services per lactation (no.) HolsteinJerseyHolsteinJerseyHolsteinJerseyHolsteinJersey >

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (17) Holstein NRR (2005 breedings) Parity 70-day NRR (%) 1st service 2nd service 3rd service 4th service 5th service >

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (18) Holstein CR (2005 breedings) Parity CR (%) 1st service 2nd service 3rd service 4th service 5th service >

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (19) Holstein regional averages (2005 breedings) Region Calving to 1st breeding (d) 70-day NRR for 1st service (%) CR (%) Services per lactation (no.) Preg- nancy rate (%) Mideast92 Midwest86 Mountain93 Northeast85 Northwest76 Southeast89 Southwest73

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (20) Holstein regional averages (2005 breedings) Region Calving to 1st breeding (d) 70-day NRR for 1st service (%) CR (%) Services per lactation (no.) Preg- nancy rate (%) Mideast9247 Midwest8646 Mountain9348 Northeast8546 Northwest7642 Southeast8944 Southwest7336

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (21) Holstein regional averages (2005 breedings) Region Calving to 1st breeding (d) 70-day NRR for 1st service (%) CR (%) Services per lactation (no.) Preg- nancy rate (%) Mideast Midwest Mountain Northeast Northwest Southeast Southwest733627

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (22) Holstein regional averages (2005 breedings) Region Calving to 1st breeding (d) 70-day NRR for 1st service (%) CR (%) Services per lactation (no.) Preg- nancy rate (%) Mideast Midwest Mountain Northeast Northwest Southeast Southwest

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (23) Pregnancy rate (PR) l Percentage of nonpregnant cows that become pregnant during each 21-day period l Advantages over days open (DO) w Easily defined w Information from nonpregnant cows included more easily w Larger (rather than smaller) values desirable l PR = [21/(DO − voluntary waiting period + 11)]100 w Voluntary waiting period assumed to be 60 days w Factor of +11 adjusts to middle day of 21-day cycle l Examples w Herd with average of 133 DO has PR of 25% w Herd with average of 154 DO has PR of 20%

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (24) Holstein regional averages (2005 breedings) Region Calving to 1st breeding (d) 70-day NRR for 1st service (%) CR (%) Services per lactation (no.) Preg- nancy rate (%) Mideast Midwest Mountain Northeast Northwest Southeast Southwest

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (25) Herds with synchronized breeding Synchroni- zation status Calving to 1st breeding (d) 70-day NRR for 1st service (%) CR (%) Services per lactation (no.) Preg- nancy rate (%) None Possible Probable Synchronized

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (26) Current breed averages BreedPR (%)DO (d) Gestation length (d) Calving interval (d) Ayrshire Brown Swiss Guernsey Holstein Jersey Milking Shorthorn

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (27) USDA pregnancy rate l Linear approximation l PR = 0.25 (233 − DO) l 1% higher PR = 4 days fewer open

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (28) Daughter pregnancy rate (DPR) l First USDA genetic evaluations in 2003 l Same across-breed animal model as for yield traits, productive life (PL), and somatic cell score (SCS) l Heritability of 4% l Predicted transmitting abilities (PTAs) reported as percentages w Daughters of bull with PTA DPR of 1 expected to be 1% more likely to become pregnant during estrous cycle than if bull had PTA DPR of 0 w Each increase of 1% in PTA DPR equivalent to decrease of 4 days in PTA DO l PTA DO approximated by −4 × PTA DPR l Example: Bull with PTA DPR of +2.0 would have PTA DO of −8

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (29) DPR trend (August 2007 base)

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (30) Bull PTA DPR frequency (Aug. 2007)

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (31) H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (31) Application of selection indexes for dairy producers

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (32) Lifetime merit indexes TraitUnits Relative value (%) Net merit Cheese merit Fluid merit ProteinPounds23280 FatPounds MilkPounds0−1224 PLMonths SCSLog−9−7−9 UdderComposite656 Feet/legsComposite333 Body sizeComposite−4−3−4 DPRPercent978 Calving abilityDollars646

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (33) Genetic merit of high-DPR Holstein bulls Trait All active AI bulls Active AI bulls with PTA DPR of ≥2.0 % Top 50% of active AI bulls based on lifetime net merit (>$245) Top 50% of active AI bulls with PTA DPR of ≥2.0% based on PTA DPR (>2.3 %) Bulls (no.)684 PTA milk (lb)838 PTA fat (lb)32 PTA protein (lb)25 PTA SCS2.94 PTA PL (mo)1.1 PTA DPR (%)−0.4 PTA DO (derived)1.6 Net merit ($)242 Semen price ($/unit)24

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (34) Genetic merit of high-DPR Holstein bulls Trait All active AI bulls Active AI bulls with PTA DPR of ≥2.0 % Top 50% of active AI bulls based on lifetime net merit (>$245) Top 50% of active AI bulls with PTA DPR of ≥2.0% based on PTA DPR (>2.3 %) Bulls (no.)68441 PTA milk (lb) PTA fat (lb)3214 PTA protein (lb)2517 PTA SCS PTA PL (mo) PTA DPR (%)− PTA DO (derived)1.6−10.0 Net merit ($) Semen price ($/unit)2425

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (35) Genetic merit of high-DPR Holstein bulls Trait All active AI bulls Active AI bulls with PTA DPR of ≥2.0 % Top 50% of active AI bulls based on lifetime net merit (>$245) Top 50% of active AI bulls with PTA DPR of ≥2.0% based on PTA DPR (>2.3 %) Bulls (no.) PTA milk (lb) ,125 PTA fat (lb) PTA protein (lb) PTA SCS PTA PL (mo) PTA DPR (%)−0.42.5−0.1 PTA DO (derived)1.6− Net merit ($) Semen price ($/unit)2425

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (36) Genetic merit of high-DPR Holstein bulls Trait All active AI bulls Active AI bulls with PTA DPR of ≥2.0 % Top 50% of active AI bulls based on lifetime net merit (>$245) Top 50% of active AI bulls with PTA DPR of ≥2.0% based on PTA DPR (>2.3 %) Bulls (no.) PTA milk (lb) , PTA fat (lb) PTA protein (lb) PTA SCS PTA PL (mo) PTA DPR (%)−0.42.5− PTA DO (derived)1.6− −11.6 Net merit ($) Semen price ($/unit)

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (37) Genetic merit of high-DPR Holstein bulls Trait All active AI bulls Active AI bulls with PTA DPR of ≥2.0 % Top 50% of active AI bulls based on lifetime net merit (>$245) Top 50% of active AI bulls with PTA DPR of ≥2.0% based on lifetime net merit (>$386) Bulls (no.) PTA milk (lb) , PTA fat (lb) PTA protein (lb) PTA SCS PTA PL (mo) PTA DPR (%)−0.42.5− PTA DO (derived)1.6− −10.4 Net merit ($) Semen price ($/unit)

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (38) DPR benefits over productive life l Additional calves produced l Decreased units of semen needed per pregnancy l Decreased labor and supplies for heat detection, inseminations, and pregnancy checks l Higher yields because more ideal lactation lengths

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (39) Lifetime value l Factors in determining economic value w Loss of about $1.50/DO w 2.8 lactations per cow w No breedings for half of cows during final lactation w Correlation of heifer and cow fertility (0.3) w Value of extra calves w Other unmeasured health expenses l Total lifetime merit value of $21/PTA DPR unit

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (40) Total Performance Index (TPI) l Calculated by Holstein Association USA (Brattleboro, VT) l Emphasis of 19% on early breeding w 10% on PL w 8% on DPR w −1% on dairy form l 95% correlation between USDA lifetime net merit and Holstein TPI

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (41) H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (41) Conclusions

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (42) Service sires l Using bulls with higher conception rates returns profit fairly quickly w Premium of $2 could be paid for semen per 1% improvement in fertility w Unit of semen from bull with ERCR of +2 worth $8 more than unit from bull with ERCR of −2 l Little genetic improvement in male fertility expected over time l Use bull fertility as a secondary selection trait after production and economic indexes

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (43) Selection for cow fertility l Selection for improved fertility possible and recommended l Most benefits delayed for 2 years or more l Select service sires for overall lifetime merit that includes daughter fertility rather than for daughter fertility alone l Producers with herd fertility problems may choose to emphasize DPR extensively, which can be done with little loss in overall net merit

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (44) Benefits of improved reproduction l Lower semen cost l Improved ability to optimize lactation and lifetime yields l Reduced culling due to delayed or failed conception l More herd replacements

H.D. Norman 2007 Dairy Cattle Reproductive Council Convention (45) Fertility emphasis l Service-sire fertility and DPR important for all management systems, but most important for grazing herds with seasonal calving l Use of a few bulls that average 3.0% for PTA DPR (equivalent to a decrease of 12 DO) could recover much of genetic decline in fertility from use of high- yield bulls for 40 years l General recommendation still is to select for overall merit based on genetic-economic index appropriate for current milk market