Brachycephales Syndrom - wenn das Atmen schwerfällt

Brachycephalic syndrome is caused by centuries of selective breeding to inhibit the growth of the facial skull. In relation to the smaller facial skull, the size of the tissues inside has not decreased during development. This leads to narrowing, malformations, and thickening in the nose and larynx. Since dogs, like cats, are obligate nasal breathers (=they must breathe through their nose), this explains why these changes cause such a wide range of problems for these animals. Breeds affected include French and English bulldogs, Pugs, Boston terriers, Cavalier King Charles spaniels, Pekingese, Lhasa Apsos, Pinschers, and Persian cats.

The most common clinical symptoms are upper respiratory tract complaints of varying severity. These increase with physical exertion. Disturbed thermoregulation is also noticeable. In severe cases, even the simplest physical activities are no longer possible due to shortness of breath.

The nostrils of affected animals are too narrow and the nasal conchae in the nose are too large for the small skull. The animals have to exert significantly more effort when inhaling in order to overcome this resistance in the airways. This creates negative pressure in the larynx and trachea, which can lead to further narrowing or even collapse of these structures. The consequences are sniffling, snoring, grunting, or wheezing noises that can be heard with every breath. These additional breathing noises are neither normal nor typical of the breed and do not reflect well-being, as is often mistakenly assumed by owners.

Additional breathing difficulties, including severe respiratory distress, can result from a palate that is too long, thickened, or flaccid. During inhalation, this palate covers the opening of the larynx, partially or completely closing it. Furthermore, a shortened pharynx, a relatively large tongue, laryngeal collapse, which is particularly common in pugs due to unstable laryngeal cartilage, or excessively developed mucosal folds can lead to worsening breathing difficulties.

The diaphragm and the stomach behind it can also be affected by the negative pressure in the chest. The constant irritation explains why brachycephalic breeds often suffer from gastrointestinal problems in addition to the obvious breathing difficulties.

Dogs with a shortened skull lack the cooling effect that dogs with a normal muzzle length get from the evaporative cooling of the nasal mucous membranes when they breathe in. This type of thermoregulation protects the inside of the skull from overheating. Short-snouted dogs are therefore very sensitive to heat and are at a significantly higher risk of heatstroke. They often start panting even when resting in order to counteract overheating.

Some brachycephalic breeds experience additional discomfort due to excessive facial wrinkles, which cover the nostrils and can lead to skin irritation.

The consequences of permanent respiratory distress and the resulting oxygen deficiency are cardiac arrhythmia with subsequent heart failure, which can ultimately lead to death. Further complications can include difficult births, brain tumors, hydrocephalus, poor dental function due to a shortened upper jaw and underbite, proptosis, corneal injuries, and obstruction of the flow of cerebrospinal fluid.

After a thorough general examination and your detailed preliminary report, your veterinarian will often be able to make a preliminary diagnosis. The throat and larynx will then be examined more closely. As this can almost only be done under sedation or anesthesia, this examination is usually combined with surgery. Further X-ray or CT scans can be used to determine the exact extent of the changes.

Animals with brachycephalic syndrome can be treated conservatively or surgically, depending on the type and severity of the symptoms. In mild cases, decongestants and anti-inflammatory drugs in combination with weight loss can help improve breathing problems. In severe cases, however, the malformations should be treated surgically if possible. Your veterinarian has various surgical techniques at their disposal to enlarge the nostrils, shorten the soft palate, or remove excess skin folds.

The prognosis generally depends on the type and severity of the changes. If treatment is started in time and no complications such as laryngeal or tracheal collapse or late effects such as heart failure have occurred, the prognosis is favorable. In many cases, breathing difficulties can be significantly improved with the help of surgery. However, this does not eliminate the cause of the disease.

In the long term, breeding hygiene measures should be taken to intervene sustainably in the development of this disease. For animal welfare reasons, extremely short-snouted animals should be excluded from breeding and breeding limits for the length and width of the facial skull should be established. These already exist in the Netherlands.