Respiratory Function Grading Scheme

What is the scheme?

The Kennel Club and University of Cambridge's Respiratory Function Grading Scheme assesses Bulldogs, French Bulldogs and Pugs for a breathing problem known as BOAS (brachycephalic obstructive airway syndrome).

The scheme advises owners if their dog is affected by BOAS and gives guidance to breeders on how to lower the risk of producing affected puppies. A selection of regionally approved assessors (vets trained especially in BOAS) have been appointed to carry out respiratory function grading on dogs of these breeds.

Dogs can be assessed from the age of 12 months and this should be repeated every two years for their lifetime, or until you stop using them for breeding.

What is BOAS?

Dogs with a flat, wide-shaped head are said to be brachycephalic (‘brachy’ meaning short, and ‘cephalic’, meaning head). The soft tissue in the nose and throat of some brachycephalic dogs may be excessive for the airways, partially obstructing the airway and making it difficult for them to breathe normally (causing heavy panting or noisy breathing). This condition is known as BOAS and is a progressive disorder that can impair a dog’s ability to exercise, play, eat and sleep.

Find out more about BOAS or watch our film on The Kennel Club Academy. 

How can I book an assessment?

You could look at our list of health testing clinics, or alternatively find your closest regional assessor below and contact them directly to book an assessment. 

Getting your dog assessed

What does each grade mean?

• Grade 0: Your dog is clinically unaffected and is currently free of respiratory signs of BOAS. If your dog is under 2 years old we suggest they have an annual health check with their own vet, as BOAS can develop later in life.
• Grade 1: Your dog is clinically unaffected but does have some respiratory noise. This does not affect their exercise performance. If your dog is under 2 years old, close monitoring by their vet is advised. All dogs should have a repeat assessment every two years with an approved assessor, as BOAS can develop later in life.
• Grade 2: Your dog is clinically affected and has moderate respiratory signs of BOAS that should be monitored and may require veterinary treatment.
• Grade 3: Your dog is clinically affected and has severe respiratory signs of BOAS and should be seen by your own vet for a thorough veterinary examination with treatment. We do not recommend that you breed from your dog.

These grades have an expiry date and dogs should be assessed every two years for their lifetime, or until you stop using them for breeding.

Breeding advice

For breeds where respiratory function grading is recommended, you should ideally only breed from two dogs that have both been through the scheme. Using these dogs will give you the information you need to reduce the chances of the puppies you breed suffering from BOAS when they grow up. If you are looking to buy a puppy of this breed you should ensure both parents are tested under the scheme. 

The way that BOAS is inherited is not fully understood and is not always entirely predictable. Using the guidelines below can help you reduce the chances of breeding puppies affected by BOAS. However, even if used responsibly, this guidance cannot guarantee that a puppy from two unaffected parents will be free from BOAS.

• Green: the lowest risk of breeding dogs affected by BOAS
• Amber: a higher risk of producing puppies that may grow up to be affected by BOAS.  Any mating of a grade 2 dog should not only consider genetic diversity, but also the health of the individual dog. BOAS is a progressive condition and special attention should be taken with any grade 2. Therefore, before considering breeding from your dog, please be aware of any respiratory issues and further consider how mating and whelping may impact your dog.
• Red: a mating which has a high risk of producing puppies that may grow up to be affected by BOAS. These matings are not recommended. Producing puppies affected by BOAS has a serious impact on their health and welfare. A mating which may produce affected puppies should never knowingly be carried out

Find a dog's BOAS grade

Our Health Test Results Finder can help you find any dog's BOAS grade, as well as results from any DNA tests and health screening schemes that we record. This tool can help you make informed decisions, whether you're a breeder trying to find a suitable healthy mate for your dog, or a puppy buyer wanting to know more about the health of a puppy's parents. 

Making balanced breeding decisions

As well as considering the implications of a dog’s respiratory function grading score, there are other equally important factors to consider when deciding whether two dogs should be mated together, such as temperament, genetic diversity, conformation, other available health test results, the general health of the dogs etc. Your breeding decisions should always be well balanced between and take into consideration the qualities and compatibility of both the sire and dam that you are considering.

Questions and answers