Differences between greyhounds and other breeds
Greyhounds Are Not “Regular” Dogs….
For hundreds of years, greyhounds have been selectively bred for speed, soundness, and good temperaments. This allows greyhounds to race together and makes them the fastest of all breeds. In this pursuit, breeders have made greyhounds distinct from other dogs. They score differently on blood tests, have unique medical conditions, and don’t handle anesthetics in the same way as other breeds. As a greyhound owner, you need to be aware of these differences when you visit your veterinarian.
Aspects of an Athlete
An obvious way that greyhounds differ from other breeds is that they have higher red blood cell counts. This is a practical advantage for an athlete because it boosts the oxygen carrying capacity of his blood. This is also a main reason that greyhounds are so desirable as blood donors. Veterinarians measure the number of red blood cells by spinning a tiny tube of blood in a centrifuge. The red blood cells separate from the plasma and pack at the bottom of the tube. The percentage taken up by the red cells is the packed cell volume (PCV). The normal range for a canine PCV is 42-62%. Greyhounds PCV ranges from 50-70%. Though a PCV of 42is normal for an average canine, a greyhound with a PCV lower than 50 is considered anemic. Greyhounds can also run normally low platelets as compared to other breeds.
Greyhounds have significantly lower thyroid hormone (T4) levels than other breeds. Some veterinarians unfamiliar with greyhounds believe these levels indicate hypothyroidism; so many greyhounds areprescribed thyroid hormone supplements. This is usually unnecessary for greyhounds, as a lower thyroid level is normal for them.
Greyhounds have significantly lower concentrations of protein and globulin than other breeds. Greyhounds’ white cell counts (WBC) are lower than average for other breeds. Their creatinines are higher than what is normal for other breeds as a function of their large lean muscle mass. An elevated creatinine level is not indicative of impending kidney failure if the BUN and urinalysis are normal. Urinalysis in greyhounds is the same as in other breeds.
Below is a chart provided to us by the Greyhound Health Initiative, which shows the relative lab work results for a greyhound as compared to “regular” dogs. Please make sure your veterinarian is familiar with these differences when reviewing your greyhound’s lab work results.
Normal Greyhounds Other Breeds
HCT/PCV 50% – 70% 42% – 62%
WBC 3.5 – 6.9 5.8 – 20.3
Platelets 110-205 173 – 497
Total Protein 4.8 – 6.3 5.1 – 7.1
Globulin 1.7 – 3.0 2.2 – 3.9
Creatinine 1.0- 1.7 0.6 – 1.6
Total T4 (nMol/L) 8 – 20 20 – 33
Greyhound hearts differ from other dogs due to the breed’s athletic nature. Compared with other breeds, a greyhound’s heart is huge (very close to the size of our hearts). This is especially true when they first come off the track and are still in racing condition, but can remain well into retirement years. Many veterinarians who are unfamiliar with greyhounds believe they have heart murmurs when they hear a noise normally generated by turbulent blood flow in a diseased heart. For a greyhound, however, the noise is generated because of the massive amount of blood pushed through the heart with every beat, and is not normally an indication of a heart problem. If your veterinarian is concerned about this, an ultrasound examination can differentiate normal heart enlargement from a diseased heart. Greyhounds often run blood pressures on the high side of normal, and have slower heart rates than other dogs, again due to the athletic nature of the breed. At rest, 60-90 is normal, but it may be faster if excited (like at the vet’s office).
Greyhounds are more sensitive to anesthesia than other breeds, mostly because of their low body fat percentage (approximately 17% as compared to approximately 35% for other breeds). They are also slow to clear some anesthetic agents through their livers. It is very important that you use a veterinarian that is familiar with greyhounds if your greyhound will undergo sedation, since greyhounds generally require less sedation for their size than other breeds. There are many safe anesthetic protocols that have been developed for greyhounds and other sight hounds. Ketamine in combination with Diazepam, as well as Propofol are widely used injectable anesthetics. The preferred gas anesthetic for greyhounds is normally Isoflurane or Sevoflurane. Often the safest anesthetic protocol is the one your veterinarian is most familiar with. The key is to use a vet that anesthetizes a lot of greyhounds and is familiar with their special anesthetic protocols.
Bald Thigh Syndrome
This is a condition seen in many greyhounds where hair loss is seen on thebackof the hind legs. It is a myth that bald thighs are caused by the greyhound lying at the back of their crate at the racing kennel. Greyhounds that have never raced and have never been crated have bald thighs. Bald thigh syndrome is not inflammatory and is not itchy. There is no known cause or specific treatment for this condition. In some greyhounds, it resolves a few months after retirement from racing. In any case, it does not hurt your greyhound and you do not need to worry about it.
Greyhounds can be prone to developing corns on their footpads. The corns are attributed to the excessively thin fatty layer under a greyhound’s footpad as well as high contusive forces between the toe bone and the footpad. Corns usually occur when a greyhound does not strike the ground evenly when they walk or run. Corns can be surgically removed but usually recur. They can be filed flat with a Dremelor emery board so they do not cause pain, but this will need to be redone fairly frequently. A good product to use for a dog with corns is a Therapaw boot, which will protect the greyhound’s foot when walking on hard surfaces.
Osteosarcomas are the most common primary bone tumor in dogs. Like other large-boned dogs, greyhounds are one of the breeds that are prone to osteosarcoma as they age. Current research has shown that this condition may be genetic, and that it is not associated with your greyhound’s athletic career, the food he was fed at the racing kennel, or whether he was injured while racing. Studies are continuing at several leading universities in an attempt to learn more about the causes and treatment of this disease.
A myth we often hear is that greyhounds have worse teeth than other dogs. This is untrue. Like other breeds, some greyhounds have stronger, whiter teeth than others. We sometimes see an accumulation of plaque on a greyhound’s teeth; however, we have our vets clean their teeth before they are placed for adoption. You can help to keep your greyhound’s teeth clean and healthy by brushing 2-3 times a week with a good product such as Pet-Z-Life oral gel and using additives such as Tropi-Clean in their water. Providing chewies, Dent-A-Stix, Greenies, and other crunchy treats to your greyhound regularly will also help to clean the teeth.
Greyhounds are Generally Healthy
On the other hand, greyhounds as a breed are healthy dogs who have few of the congenital conditions seen in other breeds, such as hip dysplasia, skin conditions, or eye problems. With proper care, greyhounds can live 12-13 years or longer. As more and more retired greyhounds find homes as pets, many more veterinarians will develop an understanding of the uniqueness of these beautiful, gentle athletes which will optimize their medical care.