REPRODUCTIVE FAILURE RESULTS IN ECONOMIC LOSSES OF GREATER THAN $9 BILLION ANNUALLY. EMBRYONIC LOSSES AVERAGE 29-35% IN HEIFERS, 40-56% IN LACTATING DAIRY AND 20-44% IN LACTATING BEEF COWS WHICH NEGATIVELY AFFECTS THE EFFICIENCY, PROFITABILITY AND SUSTAINABILITY OF THE INDUSTRY. THE HYPOTHESIS IS THAT GENOMIC SELECTION WILL REDUCE PREGNANCY LOSS IN CATTLE. TO TEST THE HYPOTHESIS AND AID THE TRANSLATION OF OUR RESULTS TO THE CATTLE INDUSTRY, WE WILL: 1) IDENTIFY GENOMIC REGIONS ASSOCIATED WITH MAINTENANCE OF PREGNANCY IN BEEF AND DAIRY CATTLE, 2) IDENTIFY THE FUNCTIONAL EFFECTS OF GENETIC VARIATION IN THESE REGIONS, 3) DEVELOP AN ASSAY TO PREDICT CATTLE THAT ARE LESS LIKELY TO LOSE THEIR PREGNANCY, AND 4) DETERMINE IF GENOMIC SELECTION FOR GENETIC VARIANTS THAT ENHANCE FERTILITY HAVE AN EFFECT ON CATTLE PERFORMANCE. WE EXPECT TO IDENTIFY GENOMIC REGIONS THAT WILL SIGNIFICANTLY IMPACT FERTILITY AND THAT WE WILL BE ABLE TO SELECT CATTLE THROUGH THE USE OF A DEVELOPED GENOMIC ASSAY. WE ANTICIPATE THAT GENOMIC SELECTION WILL REDUCE PREGNANCY LOSS WHILE STILL MAINTAINING HIGH BEEF AND DAIRY CATTLE PERFORMANCE. WITH 40.6 MILLION COWS AND 19.9 MILLION BEEF AND DAIRY HEIFERS BRED EACH YEAR IN THE US, A 0.5% REDUCTION WOULD RESULT IN THE MAINTENANCE OF NEARLY 91,000 MORE PREGNANCIES AND AN INCREASED PROFITABILITY OF ALMOST $41 MILLION ANNUALLY.