The most susceptible dog breeds to aural hemorhage, also called a “blood blister of the ears” or a painful condition that can require treatment, have been identified by vets.
If a blood vessel ruptures in the earflap, this can cause distressing symptoms for your dog.
The condition affects one in 400 British dogs each year. However, it is usually easy to spot and diagnose.
The symptoms include redness and swelling of the ears, redness in the face, and shaking and scratching at your ears.
According to the results of a study led by Royal Veterinary College, breeds with folded ears (those that drop in a V-shape or have ears with semi erect ear carriage) have higher risk of developing it compared to breeds with erect ear carriages.
The research found 14 breeds of dog that were particularly susceptible to aural hemorhage, which included Bull Terrier (Saint Bernard), Bull Terrier (French Bulldog), Irish Staffordshire Bull Terrier (Irish Staffordshire Bull Terrier) and English Bull Terrier.
Breeds that are the least at risk, meanwhile, are Greyhound, Chihuahua and Miniature Dachshund and Pomeranian.
RVC says that Bull Terrier, Saint Bernard, and French Bulldog are dog breeds most likely to develop aural hemorhage. Those with lowest risk are Greyhound, Chihuahua and Miniature Dachshund
The research was led by the Veterinary Companion Animal Surveillance System (VetCompass) – RVC’s research project that aims to investigate the range and frequency of health problems in pets.
According to the authors, ‘Based upon some previous evidence, this study hypothesized that pendulous-eared dogs had higher odds of developing aural haematoma than breeds with different types of ear carriage’.
‘However, the results did not support this hypothesis – breeds with pendulous [loosely-hanging]The odds of hearing loss in the ears were lower than those for other types.
“Conversely, the greatest odds of an aural haematoma were found in breeds that have V-shaped drops ears or semi-erect ears.
It was previously thought aural haematoma resulted from blood vessels that burst when dogs shake their head or scratch their ear too hard, but the RVC team have proposed a new theory to explain the condition’s cause.
Some people believe that repeated folding of the ear flap in certain types of ear carriages can lead to permanent damage or weakness.
RVC states that eventually, this injury can cause a bleeding episode within the ear flap.
Study by the college included a total population of 905,554 dogs receiving veterinary care at 887 UK veterinary clinics.
Researchers identified 0.25 percentage (2.249 dogs) of affected dogs after going through their medical records for one year.
If a blood vessel ruptures within the earflap, an aural hemomatoma develops. The symptoms include redness and swelling of the earflap, redness in the ears, and head shaking.
Crossbreeds were used as the baseline (the point of comparison) in order to work out the risk of getting the disease for each breed, although they were not at lowest risk.
‘Crossbreds are the most common breed type – around 20 per cent of dogs – so statistically they are a reliable group to use as the baseline,’ study author Dr Dan O’Neill at RVC told MailOnline.
“There’s also the perception that crossbreds can be healthier than purebreds, so owners of pure breeds can compare these results with their crossbred.
There were two types of ear carriage: ‘erect’, which was also called prick or upright e.g. German Shepherd) and’semierect’, also called cocked (or semi-pricked). Rough Collie, ‘V-shaped Drop’ (also called folded e.g. Hungarian Vizsla and ‘pendulous,’ also known as pendant or drop, e.g. Basset Hound
All 14 breeds had a higher risk than crossbred dogs for ear haematoma.
The German Shepherd, pictured, is a dog breed with erect ear carriage. A breed with V-shaped drops ears was more likely to have an aural haematoma than one with erect, while a breed with pendulous or stubby ear carriage had a lower chance.
Basset Hounds are characterized by ‘pendulous ears’, which can be described as those with loose, open ears. Dog breeds with pendulous ears had lower odds than the other types of ear carriage
Bull Terrier, Saint Bernard (x7.3), French Bulldog(x7.0), Irish Staffordshire Bull Terrier (3×5.5), and English Bull Terrier (4×5.4) were the breeds at greatest risk.
The risk of developing ear haematoma in twenty breeds was lower than crossbred dogs.
Greyhound, Chihuahua (x0.1), Miniature Dachshund and Pomeranian were the breeds that had the highest risk.
Comparing with breeds having erect ears carriage, V-shaped drop and semi-erect carriers had twice the chance of developing ear aural hemorhage.
However, dogs with loose-hanging earrings had a risk of x0.6. Purebreds were no more at risk than crossbreed dogs.
“Even though some breeds were more risky than others, there was a lot of breeds that were less risk,” Dr O’Neill stated.
“So, the bottom line is that the breed (and particularly the ear carriage) is what determines the risk and it’s not whether the dog is purebred of crossbred.
Hungarian Vizsla is an example of dog breeds with a “V-shaped” ear cartilage (also known to be folded).
Rough Collie, pictured, has ‘semi-erect’ (also known as cocked or semi-pricked) ear cartilage
The researchers also identified other factors that increased the risk of the condition – age and body weight.
Doggy owners with dogs that weigh more than 88lbs (30kg) were exposed to 8.5x the risks as those who had dogs that weighed less than 22lbs (10kg).
Dogs aged between 10 and 12 years had a higher risk than dogs younger than one year.
RVC believes the study will aid owners in recognizing the problem faster and seeking appropriate care.
Nature Scientific Reports has published the results of this study.