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A new article on Veterinary Practice news offers some interesting updates for our greyhound’s health.

Veterinary oncologist Guillermo Couto, DVM, founded the Greyhound Health Initiative in 2014 to build awareness in the veterinary community about the breed’s unique health issues. Since then, the organization has worked to educate veterinarians and help greyhound owners.


Raising greyhound health awareness

The Greyhound Health Initiative helps educate the veterinary community on the breed’s unique health issues

By Audrey Pavia

When veterinary oncologist Guillermo Couto, DVM, first noticed the medical idiosyncrasies of greyhounds, he was serving as a professor at The Ohio State University College of Veterinary Medicine.

During his tenure, he observed a large number of retired racing greyhounds that developed osteosarcoma. Couto also realized this ancient breed had unusual physiological, hematological, and cardiovascular characteristics, which were likely an adaptation to chasing prey.

In response, Dr. Couto created the Greyhound Health and Wellness Program at the university, which focused on research into the breed’s unique issues. He also established a financial assistance program to help adopters of retired racing greyhounds with veterinary bills and provide free chemotherapy for those undergoing treatment for osteosarcoma. But when Couto left the university in June 2013, the program started to fade.

Although he was retired, Couto wanted to continue his work helping greyhounds and their owners. In January 2014, he founded the Greyhound Health Initiative (GHI) in Dublin, Ohio, with the goal of building awareness in the veterinary community about the breed’s unique health issues. Since then, the nonprofit organization has worked to educate veterinarians about conditions seen in greyhounds, while also helping greyhound owners of both retired and active racers.

Unique greyhound issues

Simply put, greyhounds are unlike any other dog breed. This truth, as mentioned, was the driving force behind Couto’s desire to create GHI.

According to Couto, from a hematologic standpoint, these athletic dogs have higher packed cell volume (PCV) and hematocrit (HCT), hemoglobin concentration, red blood cell count, and whole blood viscosity than other breeds. A healthy greyhound has a HCT of 50 to 63 percent, something that in a dog of any other breed would result in a presumptive diagnosis of polycythemia or erythrocytosis (a term used to describe a high red blood cell mass).

Because greyhound-specific issues are still mostly unknown among many veterinarians, GHI is building awareness within both the veterinary and adoption communities,” said Greyhound Health Initiative executive director Brian Collins.

Further, the white blood cell (WBC), neutrophil, and platelet counts are lower in greyhounds than in other breeds. Most normal greyhounds have WBC of 3-5X109/L, with neutrophil counts as low as 1.8X109/L; a typical platelet count in a healthy greyhound is 80-120 X109/L. Although we do not know the mechanism for this, species of mice with very high HCT have similar hematologic features.

In addition, greyhound eosinophils lack the characteristic orange granules seen in all other breeds; the granules do not stain, thus resulting in the appearance of cytoplasmic vacuoles. These “vacuolated PMNs with bilobed nuclei” can frequently be confused with toxic bands.

And that’s not all. According to Couto, the serum biochemical profiles in greyhounds also have values that are typically outside the reference range for dogs. Mainly, the serum creatinine concentrations are high (1-2.2 mg/dL), and the total serum protein (5-6 gm/dL) and globulin (1.8-2.5 gm/dL) concentrations are lower than in other dogs; low serum acute phase protein concentrations account for the lower globulin concentration. Depending on the instrument used, other values may also be outside the reference range for dogs. Serum calcium (both total and ionized) and magnesium are lower than in nongreyhounds. The results of venous or arterial blood gas analysis and cooximetry in greyhounds also yields results outside the reference range for dogs.

Greyhounds do not metabolize drugs like other dogs do, Couto noted. Their concentration of hepatic cytochrome P-450 enzymes (CYP) is significantly lower than in other breeds, thus accounting for erratic metabolism of some drugs when polypharmacy is used.


The term relative risk (RR) describes how much more likely a breed is to develop a disease, in comparison with a group of mixed breed dogs. If the RR is 2, the breed is twice as likely to develop that disease. The RR for osteosarcoma in greyhounds is 17. This is likely due to several gene mutations recently described.


Programs that help hounds

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