Why does my sighthound's blood work always look abnormal?

Because many of a sighthound's values naturally fall outside the ranges built on the average dog. Haematocrit and red cells are higher, platelets and white cells tend to be lower, creatinine is raised by the large muscle mass and baseline thyroid hormones are often lower. This is not disease, it is breed physiology. The ideal is to use breed specific reference ranges where available and to compare results with the animal's own history.

Is anaesthesia really riskier in a sighthound?

It is not riskier when handled with breed awareness, but it can be if treated like any other dog. The scarcity of fat and a distinctive metabolism make some anaesthetics longer lasting, with slower recoveries, and body temperature drops quickly during procedures. With an adapted protocol, tests interpreted correctly and good temperature monitoring, procedures are as safe as in other dogs.

Is my sighthound too thin?

In most cases, no. The breed is constitutionally lean, with very little body fat, and in a fit individual the last ribs and sometimes the vertebrae are palpable or barely visible. Judging body condition by the average dog's yardstick often leads to overfeeding. If in doubt, have the body condition assessed by the vet using breed criteria, rather than aiming for a more covered look that does not suit a physique built for running.

Why does my sighthound shiver and always seek warmth?

Because of the combination of very little insulating fat and, in many breeds, a short, sparse coat. This makes it poorly tolerant of cold and damp, and it is normal for it to seek blankets, warm spots and soft beds. Help it with a close fitting coat on winter outings, a bed raised off the cold floor and sheltered from draughts, and shorter walks when the temperature drops. If the shivering appears in the warm too or comes with other signs, have it checked, because then it is not down to thermoregulation alone.

Breeds and species9 min readUpdated on August 16, 2026

Sighthounds: the physiology and clinical quirks that change decisions

Why sighthounds have blood work, drug sensitivity and skin that differ from the average dog, and what owner and vet must know to avoid getting it wrong.

Audience: Pet owners, Veterinarians
Species: Dog
Scope: Valid everywhere, European Union, Italy

Sighthounds, from the greyhound to the whippet, from the galgo to the Italian greyhound and on to the saluki and borzoi, share a physiology that sets them apart from the average dog in ways with very concrete clinical consequences. They are built for high speed pursuit: a great deal of muscle, almost no fat, a large heart and blood unusually rich in red cells. This design, which makes them superb athletes, shifts several laboratory values outside the reference ranges built for the average dog, changes the response to anaesthetics and drugs, and exposes them to typical minor problems such as skin lacerations and cold sensitivity. Knowing these quirks avoids two mirror image mistakes: alarm over values that are normal in a sighthound, and underestimating risks that are real in this type. This page gathers what someone living with a sighthound should know, and what is useful to remember for those who treat one.

A group with a physiology built for running

The sighthound is a chase by sight dog, selected for short, blistering bursts of speed. The body reflects that function: high muscle mass, a very low body fat percentage, a deep chest and a proportionally large heart. The blood carries more oxygen because it holds a higher share of red cells than in other dogs, an advantage at speed that nonetheless alters resting blood work.

The scarcity of fat is not a cosmetic detail. Fat is a thermal insulator and a metabolic reserve, and its near absence explains why these dogs feel the cold, injure themselves easily over bony prominences and handle certain fat soluble drugs differently. Anyone who looks at a lean sighthound and thinks it is underfed is usually wrong: the dry build, with ribs barely visible, is the breed norm, not a sign of disease.

Laboratory values that fall outside the standard ranges

This is where the most frequent misunderstandings arise. Much of a sighthound's blood work falls outside the reference ranges built on the average dog, and an unprepared eye can read as pathological a value that in the breed is entirely physiological. Studies of greyhound populations have described consistent, reproducible differences.

Typical sighthound differences versus the average dog
Parameter	In the sighthound	Risk of error
Haematocrit and red cells	Higher than average	Mistaking the breed norm for dehydration or polycythaemia
Platelets	Tend to be lower	Suspecting a clotting disorder that is not there
White cells	Often lower	Reading a normal value as immunosuppression
Creatinine	Higher due to large muscle mass	Diagnosing a kidney problem that does not exist
Total protein	Sometimes slightly lower	Worrying needlessly about low protein
Thyroid hormones	Lower baseline values	Treating an apparent but unreal hypothyroidism

The practical consequence is simple: a sighthound's tests should be read with breed specific reference ranges where available, and always in the animal's clinical context, not merely compared with the normal values column printed on the report. Telling the vet the dog is a sighthound, before even reading the results, avoids needless workups and unjustified worry.

Sensitivity to drugs and anaesthesia

The combination of little fat, high muscle mass and a distinctive liver metabolism makes sighthounds more sensitive to several drugs, and especially to some anaesthetics. Historically the issue emerged with certain induction agents that, without fat stores to distribute into, stayed active longer and greatly prolonged recovery.

Recovery from anaesthesia can be slower and should be managed with protocols and agents chosen with the breed in mind, not the standard scheme.
Doses of many drugs should be calculated on lean mass, because a sighthound's weight is almost all muscle and bone, not fat.
Some antiparasitics and drugs acting on the nervous system require care in lines carrying a known genetic sensitivity in membrane transporters.
Body temperature must be watched closely during and after anaesthesia, because without insulation these dogs cool quickly on the table.
Even common sedatives and painkillers can have more marked or longer lasting effects than expected and should be titrated cautiously.

None of this means a sighthound cannot be anaesthetised safely: it means it must be anaesthetised with breed awareness. A thorough pre anaesthetic assessment, with tests interpreted correctly and an adapted protocol, makes procedures as safe as in other dogs. The danger is not the anaesthesia itself, it is anaesthesia run as if the sighthound were just any dog.

Thin skin, teeth and other quirks

The sighthound's skin is famously thin and poorly protected by subcutaneous fat and a thick coat. The result is frequent lacerations, sometimes striking in extent, caused by brambles, fences, edges or play with other dogs, which often need suturing even when the wound looks superficial.

Skin wounds heal well but tend to gape widely because of the scarcity of elastic tissue and fat: it is better to have them assessed than to dismiss them.
Periodontal disease is common, particularly in the small breeds such as the Italian greyhound, and should be prevented with regular oral hygiene from a young age.
Over bony prominences, such as elbows and hocks, pressure sores and callosities form easily on hard surfaces: soft, padded beds are needed.
In greyhounds, so called corns are described, painful thickenings of the pads that cause lameness and need dedicated management.
The ears and the thin tail are vulnerable to trauma and tip injuries that bleed for a long time and heal slowly.

Many of these fragilities are managed with the environment rather than with medicine: soft resting surfaces, play areas free of sharp edges and checked fencing sharply reduce the frequency of accidents. A regular check of skin, pads and mouth allows problems to be caught while they are still small.

Temperature, cold and everyday management

The near absence of insulating fat and, in many breeds, a short, sparse coat make the sighthound poorly tolerant of cold and damp. This is not a character weakness, it is a matter of physics: a lean body with little covered surface loses heat far faster than a sturdy, well coated dog.

Practical measures for everyday life
Situation	Measure
Winter outings	A close fitting coat for short coated breeds, shorter walks in hard cold
Resting at home	A soft bed raised off the cold floor, in a spot sheltered from draughts
Physical activity	Gradual warm up, short sprints and proper recovery, avoiding hard, slippery ground
Feeding	A ration calibrated to the lean build, without chasing an average dog's weight
Clinic procedures	Always flag that it is a sighthound and monitor temperature during procedures

In terms of temperament, many sighthounds are calm dogs that love to rest, able to sprint for a few seconds and then sleep for hours. This alternation between bursts of speed and long spells of quiet should be respected: they are not dogs for prolonged, constant effort, and forcing them into endurance activity unsuited to their physiology is counterproductive.

What to tell the vet and what to monitor at home

The single most useful thing a sighthound owner can do is state the breed before every test or procedure. It sounds obvious, but many mistakes arise precisely from interpreting correct data with the wrong yardstick.

Before a blood draw or a procedure, remind the vet that the dog is a sighthound, so the values are read in the right context.
Keep and bring the previous reports: in a sighthound, comparison with the individual history matters more than the species average.
Monitor weight and body condition by breed criteria, without aiming for a more covered physique than the build calls for.
Check skin, pads, elbows and mouth regularly, and have every skin wound assessed even if it looks minor.
Before an elective anaesthesia, ask for a careful pre operative assessment and a protocol designed for the breed.
Note episodes of lameness, slow recovery after sedation or cold sensitivity, useful information for future decisions.

Living with a sighthound is, most of the time, surprisingly simple: they are clean dogs, often placid and very affectionate. The quirks described do not make them fragile, they make them different in predictable ways. Knowing these differences in advance is what lets you enjoy the breed without being alarmed by a high haematocrit or a slightly slower recovery.

Frequently asked questions

Why does my sighthound's blood work always look abnormal?: Because many of a sighthound's values naturally fall outside the ranges built on the average dog. Haematocrit and red cells are higher, platelets and white cells tend to be lower, creatinine is raised by the large muscle mass and baseline thyroid hormones are often lower. This is not disease, it is breed physiology. The ideal is to use breed specific reference ranges where available and to compare results with the animal's own history.
Is anaesthesia really riskier in a sighthound?: It is not riskier when handled with breed awareness, but it can be if treated like any other dog. The scarcity of fat and a distinctive metabolism make some anaesthetics longer lasting, with slower recoveries, and body temperature drops quickly during procedures. With an adapted protocol, tests interpreted correctly and good temperature monitoring, procedures are as safe as in other dogs.
Is my sighthound too thin?: In most cases, no. The breed is constitutionally lean, with very little body fat, and in a fit individual the last ribs and sometimes the vertebrae are palpable or barely visible. Judging body condition by the average dog's yardstick often leads to overfeeding. If in doubt, have the body condition assessed by the vet using breed criteria, rather than aiming for a more covered look that does not suit a physique built for running.
Why does my sighthound shiver and always seek warmth?: Because of the combination of very little insulating fat and, in many breeds, a short, sparse coat. This makes it poorly tolerant of cold and damp, and it is normal for it to seek blankets, warm spots and soft beds. Help it with a close fitting coat on winter outings, a bed raised off the cold floor and sheltered from draughts, and shorter walks when the temperature drops. If the shivering appears in the warm too or comes with other signs, have it checked, because then it is not down to thermoregulation alone.

What to do next

Sighthounds are athletes built with lots of muscle and almost no fat, and this changes clinical decisions. Their tests often fall outside the average dog's ranges, with high haematocrit, low platelets and white cells and raised creatinine, so they should be read with breed references and compared with the individual history. Always flag the breed before blood draws and anaesthesia, calibrate diet and weight to the lean build, protect the thin skin and the dog from cold, and have every skin wound assessed even if it looks minor.