Genetic Selection as a Tool for Battling the Decline in Reproductive Performance: A Dairy Perspective Kent A. Weigel, Ph.D. Department of Dairy Science University of Wisconsin

Background

Reproduction of Lactating Cows vs. Yearling Heifers CowsHeifers Duration of estrus (hr) Multiple ovulation rate (%) Pregnancy loss (%) Anovulation (%) Diameter of the ovulatory follicle (mm) Estrous cycle length (d) Lopez et al., 2004

Estrus Characteristics Lopez et al., 2004

Duration of Estrus Lopez et al., 2004

Multiple Ovulation Lopez et al., 2004

Twinning Rate in Holsteins Kinsel et al., 1998 Silva del Rio et al., 2006 Year of Conception Twinning (%)

Importance of Body Condition Score

Anovulatory Condition Lopez et al. 2004

Anovulatory Condition Lopez et al. 2004

Santos et al., 2004 Low milk = 36 kg/d High milk = 52 kg/d Milk Yield vs. Embryonic Loss between 31 to 45 d of Pregnancy P = 0.81

N=250 Body Condition vs. Embryonic Loss Silke et al., 2004 N=103N=147 P < 0.05

Selection for Female Fertility

Indirect Selection for Fertility  Length of Productive Life (available since 1994)  Total months in milk by 7 years of age  Limit of 10 months per lactation  Rewards a short calving interval  Dairy Form (received negative economic weight in 2005)  Poor body condition = poor fertility  Can measure milk production directly  Shouldn’t reward angularity

Evaluation of Female Fertility  USDA Animal Improvement Programs Laboratory introduced national genetic evaluations for female fertility in 2003  Dairy sires from all breeds are evaluated based on the fertility of their daughters  The animal model system for fertility is the same as for production traits  Evaluations are released 3 times per year

Evaluation of Female Fertility  Input data are days open measurements from the DHI milk recording system  Days open (calculated from the last reported insemination) is confirmed with subsequent calving dates, if possible  Animals with no subsequent calving are assigned an arbitrary value of 250 days  Days open data are transformed to 21-day pregnancy rates

Today’s Fertility Data  Introduced in February 2003 > 40 million records > 16 million cows  Based on days open data, including:  Breeding date confirmed by calving (57%)  Breeding date without next calving (19%)  Breeding date conflicts with next calving (5%)  Next calving, but no reported breeding (6%)  Culled due to infertility (5%)  No fertility information (8%)  Published “daughter pregnancy rate”

Example Bulls for DPR 1H6360 Wizard DPR +3.7% 1% DPR ≈ 4 days open 200H3101 Freelance DPR -3.8% The 21-day pregnancy rate of Wizard daughters will be 7.5% higher, on average than for Freelance daughters, and Wizard daughters will have 30 fewer days open per lactation

Genetic Trend in Milk Yield Genetic Trend in Daughter Pregnancy Rate Genetic Correlation = 0.31 Introduction of Productive Life

Selection for Male Fertility

Evaluation of Male Fertility  Regional evaluations of male fertility have been carried out by dairy records processing centers for many years  USDA-AIPL recently began computing “phenotypic” evaluations for service sire conception rate (i.e., direct effect)  Evaluations are published as the expected percentage change in conception rate, including both genetic and environmental factors

Example Bulls for SCR 29H10483 Jammer SCR + 4 9,731 inseminations 14H4099 Billion SCR - 3 4,422 inseminations Expect a 7% difference between these bulls in conception rate, under equivalent management conditions

Additional Fertility Traits  As a by-product of evaluations for service sire conception rate, two new female fertility traits were introduced in 2009  Cow conception rate measures the expected difference in conception rate due to the female (i.e., maternal effect) in lactating animals  Heifer conception rate measures the expected difference in conception rate in non-lactating animals

Reproductive Events (up to 20 segments) Type of reproductive event code Date of reproductive event (YYYYMMDD) National Fertility Database H Observed in estrus (heat) but not inseminated S Synchronized estrus event (injection or other methods) A Artificial insemination N Natural service breeding E Embryo donation I Embryo implantation (reporting sire of embryo) J Embryo implantation (reporting dam of embryo) P Confirmed pregnant O Confirmed not pregnant (open) X Cow given a "do not breed" designation G AI breeding with gender selected semen USDA Format 5

Selection for Animal Health

Pregnancy Risk by Calving Disorder Calving Disorder Risk of Pregnancy

Stillbirths and Female Fertility Bicalho et al. (2007)

Pregnancy Risk by Repro. Disorder Reproductive Disorder (in 1 st 75 d Postpartum) Risk of Pregnancy

Pregnancy Risk by Mastitis Infection Mastitis Infection (in 1 st 75 d Postpartum) Risk of Pregnancy

Pregnancy Risk by Metabolic Disorder Metabolic Disorder (in 1 st 75 d Postpartum) Risk of Pregnancy

Pregnancy Risk by Mobility Disorder Mobility Disorder (in 1 st 75 d Postpartum) Risk of Pregnancy

Dairy Comp 305  Valley Ag Software, Tulare, CA  ~ 4,000 large herds PCDART  DRMS, Raleigh, NC  ~ 3,000 medium-sized herds DHI-Plus®  DHI-Provo, Provo, UT  ~ 300 very large herds Management Software

Displaced AbomasumKetosisMastitisLamenessCystic OvariesMetritis DAKETOSISMASTABCSCYSTMET/RP D.A.KETOTICRFABSSCYSTGMET LDAKETLFHROTCYSTOMETR RDAKETORRHFROTCYSTICRP L-DAKETOSLRLAMINITRCYSTRETAINP R-DAKET1MLFQLAMELCYSTRETP DASKET2MLRQWRAPCYSTROINFU DALFKET3MRRQLAMICYSTLOINF DARTKETIMRFQLIMPMTRI DARKETRMLFSOREFTRETN DALKETSMLRABCSRRRPL KETHMRRABCSLRRPIN KETDMRFFOOTRPRE KETPRFMTFEETUCND METBLFMTRTPL LRMTUINF RRMTPYOM M2TITUTCN MASTALLRE-PLA MAST2Q MAST3Q Disease Codes

Summary of the Data (Alta Advantage herds and selected DRMS herds) Zwald et al., 2004 Displaced AbomasumKetosisMastitisLameness Cystic OvariesMetritis Herds Cows75,25252,898105,02950,61165,08097,316 Sires Lactation Incidence Rate 3%10%20%10%8%21%

Heritability Estimates Zwald et al., 2004 Displaced Abomasum14% Ketosis6% Mastitis9% Lameness4% Cystic Ovaries4% Metritis / Retained Placenta6%

Predicted Transmitting Abilities for Daughter Health Zwald et al., 2004 Displaced Abomasum KetosisMastitisLameness Cystic Ovaries Metritis Disease Probability per Lactation (Best 10 Sires) Disease Probability per Lactation (Worst 10 Sires)

Differences in exposure e.g., mastitis pathogens Inconclusive test results e.g., Johne’s disease Incomplete reporting incorrect diagnosis underestimated severity selective treatment temporary recording Restrictions on access to the data Challenges with Health Traits

Health Events (up to 20 segments) Type of health event code Date of health event (YYYYMMDD) National Health Database Health Traits Cystic OvaryCYST Diarrhea/ScoursDIAR Digestive Problem/Off FeedDIGE Displaced AbomasumDA-- Downer CowDOWN DystociaDYST Johne's Disease (clinical)JOHN Ketosis/AcetonemiaKETO LamenessLAME Mastitis (clinical)MAST MetritisMETR Milk Fever/HypocalcemiaMILK Nervous System ProblemNERV Reproductive problem other than CYST, DYST, METR, RETPREPR Respiratory ProblemRESP Retained PlacentaRETP Stillbirth/Perinatal SurvivalSTIL Teat InjuryTEAT Udder EdemaEDEM Management Traits Body Condition ScoreBCS- Milking SpeedSPEE TemperamentTEMP USDA Format 6

Lifetime Net Merit (NM$) 23% Fat 23% Protein 17% Productive Life -9% Somatic Cell Score 6% Udder Composite 3% Feet & Legs Composite -4% Body Size Composite 9% Daughter Pregnancy Rate 6% Calving Ability

Impact of Crossbreeding

Breed Differences (vs. Holstein) Genetic differences between breeds represent twice the difference in average predicted transmitting ability (PTA) from the USDA-AIPL multi-breed genetic evaluations AyrshireBrown Swiss GuernseyJerseyMilking Shorthorn Milk Yield (lb)-5,258-4,204-6,107-6,516-7,106 Fat Yield (lb) Protein Yield (lb) Somatic Cell Score Productive Life (mo) Daughter Preg. Rate (%)

fertility during1 st lactation Different from pure Holsteins: † P<0.10, * P<0.05, ** P<0.01 Fertility of Crossbred Cows (Heins et al., 2006) Pure Holstein Normande x Holstein Montbeliarde x Holstein Scandinavian Red x Holstein No. Cows Days Open156133**137**142**

Fertility and Udder Health of Crossbred Cows (Dechow et al., 2007) Holstein ½ Swiss ½ Holstein ¾ Swiss ¼ HolsteinBrown Swiss Number of Cows Age at Calving (mo)25.9 a 25.7 a 26.6 b Days Open156 b 144 a 153 ab 156 b Somatic Cell Score2.73 ab 2.54 a 2.66 ab 2.78 b Different superscripts within a row indicate Statistical significance at the P<0.05 level

survival during1 st lactation Different from pure Holsteins: † P<0.10, * P<0.05, ** P<0.01 Longevity of Crossbred Cows (Heins et al., 2006) survival until 2 nd calving Pure Holstein Normande x Holstein Montbeliarde x Holstein Scandinavian Red x Holstein No. Cows until 30 d96%98%99%98% until 150 d93%97%* 96% until 305 d86%94%*96%*93%* No. Cows within 14 mo44%62%**64%**60%** within 17 mo61%76%**78%**73%** within 20 mo67%79%**83%**77%**

UW-Madison Dairy Science…Committed to Excellence in Research, Extension and Instruction Any Questions?