Understanding the Power of the X Factor

Marianna Haun wrote about research on large hearts and racehorse performance in her previous book, The X Factor. After three years of continued research and more than 1,000 horse scientifically measured by equine cardiologist Dr. Fred Fregin, Haun reports the newest findings in heart score and pedigree research. She shows readers the photos, pedigrees and actual ECG records of such Thoroughbred racehorses as Northern Dancer, Cigar, Mr. Prospector and more. Standardbred and Quarter Horse racehorses are also featured.