"All heart" of greyhounds may be genetic, study finds
By Kay Garrett
Racing greyhounds and racehorses have very large hearts, the better to pump blood in a hurry.
But is the heart naturally larger by nature or does it bulk up with lots of exercise?
A recent study published by scientists at Kansas State University found that the heart size of greyhounds is probably the result of genetics, not exercise.
Writing in the April 1995 issue of the American Journal of Veterinary Research, the KSU researchers report on a comparative study of 50 greyhounds - 29 racing and 21 nonracing. This study was done as part of a larger suruey of greyhound diseases.
According to veterinary patho|ogist Polly Schoning, an enlarged heart and a high heart-to-body weight ratio account for the running ability of extraordinary animal athletes like greyhounds and race horses.
"The most interesting finding for us was. a consistent heart-to-body weight ratio," she said. Regardless of age, sex or racing status, that ratio remained the same.
"Our research supports the hypothesis that the larger heart of these dogs probably has a genetic basis," Schoning said.
The researchers studied body weight, heart weight and determined heart-to-body weight ratios of racing and nonracing dogs, taking into account effects of age and sex.
KSU co-authors with Schoning are Howard Erickson, department of anatomy and physiology, and George Milliken, department of statistics. The research was supported the Kansas Agricultural Experiment Station.
June 15, 1995