Disorders of the upper respiratory tract in dogs of brachycephalic breeds

Zabegin

Editor-in-chief, editor of the section “Infectious and invasive diseases”

Candidate of Biological Sciences, author of more than 150 scientific and popular science articles, Official representative WEVA in Russia, CIS and Central Asian countries, FEI veterinary delegate, President of the Equine Veterinary Association, member of the UET Animal Welfare Committee.

Hereditary veterinarian. After the fourth year of study at Moscow veterinary academy them. K.I. Skryabina got an internship in the laboratory of equine viral diseases of the All-Union Scientific Research Institute of Experimental Veterinary Medicine (VIEV), where she worked for a long time. There, under the guidance of Professor Konstantin Pavlovich Yurov, a candidate’s thesis “Typing of equine herpesviruses using DNA restriction analysis and the search for a vaccine strain” was written. The result of this work was the creation of monovalent (rhinopneumonia) and polyvalent (influenza-rhinopneumonia) inactivated vaccines. In 1998, she completed an internship on equine viral arteritis at the Weybridge State Veterinary Research Laboratory (UK), and in 2004 at the University of Kentucky (USA). For many years, Ekaterina led in VIEV laboratory diagnostics viral diseases of horses, necessary for the import and export of animals. She is one of the world's top 15 experts on equine viral arteritis and, as an official lecturer for the World Equine Veterinary Association on equine infectious diseases, frequently speaks abroad.

In 1999 E.F. Zabegina became one of the initiators of the revival of the tradition of holding horse shows in Russia. As a result, the International Horse Show “Equiros” was organized and is held annually. And two years later - in 2001 - Ekaterina created the Equine Veterinary Association, whose members were specialists working in the field of equine veterinary medicine.

In 2000, at her own risk, Ekaterina held the first internal conference on equine diseases, and already in 2008, under her leadership, for the first time in Russia, the 10th Congress of the World Equine Veterinary Association (WEVA) was successfully held. Today, as part of the programs postgraduate education Ekaterina professionally organizes conferences, seminars and master classes on equine veterinary medicine. In her track record There are already more than two hundred such events.

Since 2004 E.F. Zabegina actively cooperates with the Russian Equestrian Federation (FKSR), in 2004 she received the status of FEI Veterinary Delegate ( International Federation equestrian sport), and since that time has served as the FEI veterinary delegate at many international equestrian competitions in show jumping, eventing, driving and distance riding, held within the FEI in Russia and abroad. In 2005, she was appointed chief of the Russian national team at the World Distance Equestrian Championships in Dubai (UAE). In 2007, on behalf of the Federal Investigative Committee, she completed an internship on horse doping issues at the University of Davis, USA.

In 2003, Ekaterina founded her own company, Equicenter, specializing in the supply of veterinary instruments and equipment. With the direct participation of the company, a number of veterinary clinics not only in Moscow, but also in other cities of Russia. Equicentre also acts as an expert in providing technical advice and equipment for hippodromes and equestrian facilities. One of the main achievements in this area is the implementation of the Akbuzat hippodrome project in Ufa, which is rightfully considered one of the best hippodromes in Europe.

In 2006, Zabegina’s work and achievements were awarded an honorary award from the Equine Veterinary Association “Veterinary Cross”, in 2008 - prestigious award in the field of veterinary medicine “Golden Scalpel”, in 2013 - a medal of the State Veterinary Service of Moscow.

Tracheal collapse is a syndrome characterized by flattening of the tracheal rings or laxity of the dorsal tracheal membrane. Found mainly in decorative and dwarf breeds dogs – Yorkshire Terriers, toy terriers, chihuahuas, Pomeranians.

Primary weakening of the cartilage of the tracheal rings is associated with insufficient content of glycoproteins and glycosaminoglycans and can be considered as an anatomical defect. Symptoms usually appear in dogs older than 5-6 years, both spontaneously and after provocation by some factor. Complaints are manifested by cough, deterioration general condition, stridorous (“wheezing”) breathing and severe cases– respiratory failure.

Predisposing factors causing clinical manifestations of tracheal collapse may be associated with obesity, respiratory infections, tracheal intubation during anesthesia, neck injury (including with a sharp tug on the collar), allergic reactions to aerosols (for example, by inhalation tobacco smoke, vapor detergents, strong-smelling substances.)

The trachea is tubular organ connecting the larynx and bronchi. The rigid structure of the tracheal tube is provided by cartilaginous half-rings, with the open side facing dorsally (upwards, towards the spine). This space is closed by connective tissue ligaments - the tracheal membrane.

Anatomically, tracheal collapse is a change in the normal (almost circular) cross-section of the trachea due to flattening of the rings, causing the dorsal connective tissue membrane to sag inward into the tracheal cavity. This leads to a decrease in the diameter of the trachea, leading to disruption of normal patency. The sagging may affect the entire length of the trachea or only the cervical or thoracic regions.

When the trachea collapses, it develops chronic inflammation mucous membrane. This results in the loss of functioning epithelium and its replacement fibrous tissue, which makes the cough even worse. In some dogs, over a long period of time, collapse leads to pulmonary hypertension and the development of changes in the right parts of the heart.

Symptoms

The syndrome is characterized by a chronic cough that worsens with emotional excitement. This is usually a dry, loud cough that occurs when pulling on a leash, exposure to cold air, or after drinking. There can be both short, isolated coughs and paroxysmal coughs, during which the owner notes a blue discoloration (cyanosis) of the tongue and mucous membranes. A cough can be induced by pressing on the trachea, the so-called “positive tracheal reflex”. At the same time, the animal tolerates physical activity well.

The manifestation of similar symptoms in young dogs and puppies may be associated with tracheal hypoplasia - this is associated with fusion of the tracheal rings and is more common in English bulldogs, bullmastiffs.

In some animals, tracheal collapse is asymptomatic throughout life and can be accidentally detected on x-ray. Excess weight significantly aggravates the problem.

It is necessary to differentiate this disease from chronic tracheobronchitis dogs, foreign bodies, neoplasms and polyps of the trachea, heart disease.

Cardiac diseases that are accompanied by cough are associated with an enlargement of the left atrium. Small dog breeds are predisposed to endocardiosis mitral valve (mitral valve insufficiency). In this case, increased left atrium compresses the left bronchus and displaces the trachea dorsally (towards the spine). This is especially worth considering in sedentary dogs. Cough in cardiac diseases is often wet and productive. At the appointment, during auscultation of the lungs, the doctor can identify noises that overlap with tracheal sounds. In animals with a long-term disease, murmurs in the right side of the heart can be detected.

Diagnostics

To confirm the diagnosis, a lateral radiograph of the trachea is required. It is advisable to take photographs during the inhalation and exhalation phases - this is due to the fact that collapse occurs during inhalation cervical region, and when exhaling collapse thoracic. In severe cases, narrowing of the trachea or sagging of the dorsal membrane can also be visualized on regular films.

The gold standard for diagnosing this disease is endoscopic examination (tracheobronchoscopy). During endoscopy, the narrowed lumen is clearly visible. The degree of collapse can be determined by the sagging of the dorsal membrane. Membrane sagging by 25% is attributed to the first stage, a displacement of 50% to the second, a displacement of 75% to the third, and complete closure of the lumen to the fourth.

The prognosis in severe cases is unfavorable, in mild cases it is favorable. During tracheoscopy, it is also advisable to obtain tracheal swabs and examine them for the presence of microorganisms and sensitivity to antibiotics. This is necessary to differentiate the diagnosis and to more effectively prescribe antibiotics that control secondary bacterial inflammation.

Treatment

Treatment is aimed not at the cause of the disease, but at correcting the dog’s condition. Obese animals need to lose weight. Eliminate the use of a collar and transfer the animal to wearing a harness.

If the doctor believes that the cause of increased symptoms is an infection, then additional antibiotics are prescribed. Short courses of glucocorticoid hormones may be indicated - they relieve inflammation and swelling, however, the use of glucocorticoids can increase bacterial inflammation and also provoke weight gain, so treatment is carried out only under the supervision of a physician. The maximum effect of glucocorticoids is usually observed on days 7-10, then the dosage is gradually reduced and removed completely.

There are some branches of veterinary medicine that seriously lag behind similar areas of “human” medicine. These include cardiology. Therefore, it is in the interests of the animal owner to identify heart defects in the dog in a timely manner, since early stages there is a chance to start effective drug treatment, which will maintain the quality of life of the animal at an acceptable level.

The vast majority of dogs do not suffer from disease coronary artery, even if their nutrition is far from perfect (unlike humans). But they are highly susceptible to developing defects that cause heart failure and congestion in both circulation circles. All this hits the internal organs hard.

Like humans, a dog can live a very long time with serious heart disease without any severe symptoms will not appear at this time. Only an attentive owner can notice sudden periods of weakness and weakness, which sometimes manifests itself in the dog even after minor physical exertion. In 95% of cases, all defects are acquired, resulting from some serious infection. This happens to middle aged dogs and elderly dogs. The most difficult heart problems for animals are:

• Mitral valve stenosis. In dogs, it often happens that with age it becomes coarser and, due to increased rigidity, can no longer prevent the outflow of blood during contraction of the left ventricle.

• associated with myocardial degeneration. It may degrade or be replaced altogether connective tissue, as a result of which the organ can no longer contract, driving blood through the vessels.

• . As a rule, they occur with lesions of the conduction system of the heart: nerve impulses cannot spread throughout the organ, causing myocardial contractions to become irregular.

• Pericardial diseases. Although the latter is just a serous “sac” for the organ, when it becomes inflamed or dropsy, a functional one quickly develops.

Read also: Weeping dermatitis in a dog: signs, symptoms, treatment, prevention

Separately, we need to dwell on cardiomyopathies! There are three types diagnosed in dogs: hypertrophic, dilatational And restrictive. Two are especially dangerous latest varieties. In the case of the dilated type, the myocardium thins and becomes flabby. With a restrictive type of disease muscle is generally replaced by a connecting one.

Symptoms

All defects can be divided into two large types: congenital And acquired. The first variety is quite rare in dogs. As a rule, the only manifestations birth defects initially there are only heart murmurs. In young animals they can only be heard at times when the puppy is very excited or agitated. The defect can be diagnosed with reasonable confidence starting at the age of four to six months.

In dogs, classic defects include mitral valve disease and congenital left ventricular cardiomyopathy. Whatever the defect, it leads to one outcome - the heart cannot function normally. In this case, the dog’s lifespan is shortened, its overall quality. If the defect is insignificant, the animal can live with it for years, and the disease will not manifest itself in any way. How can you tell when it's time to take your pet to the vet? Here are the main symptoms of heart disease in a dog:

• Barking, sharp, dry cough, usually worse at night.

• Dyspnea.

• Weight loss. Note that a dog can lose weight in just a couple of weeks.

• The dog is constantly tired and apathetic.

• In severe cases, it can lead to sudden fainting.

• Likewise - sharply bloated belly, which occurs during particularly serious stagnation in big circle blood circulation

Read also: Carcinoma in dogs: types and diagnosis of the disease

Diagnostics and therapy

To diagnose any heart defect, all types of tests are taken, including urine and blood tests, and radiography is done. chest, ECG and ultrasound. But at present, a heart study cannot be considered complete and reliable if Doppler echocardiography has not been performed (in this case, the speed and direction of blood movement is recorded).

What treatment can be used for heart disease in a dog? It's not easy here. If the defect is insignificant and does not manifest itself in any way, then nothing needs to be done. If we're talking about about serious pathology heart valve, then an operation is desirable here... But there are practically no cardiac surgeons among veterinarians. So 60% of puppies with mitral valve defects die before they even reach six months of age.

So the main method of therapy is medication. Angiotensin-converting enzyme inhibitors and ACE inhibitors are widely used in treatment. These medicines reduce the load on the heart and improve myocardial nutrition. If you start treatment in the early stages of the disease, there is a chance to seriously slow down the development of the pathology. These medications cannot eliminate the defect itself, but they can significantly alleviate the symptoms.

Other drugs used for treatment include beta blockers, nitroglycerin, and digitalis drugs to slow the heart rate and stabilize the striated muscles of the organ. Diuretics such as Lasix help prevent congestion from developing.

It is important to understand the differences between heart disease and heart failure. The second is a consequence of the first. The angiotensin-converting enzyme inhibitors mentioned above are often used specifically to improve the quality of life of a dog with advanced heart failure. It is important to remember that when serious cases cardiomyopathy or mitral valve insufficiency, the development of blood clots must be prevented. Heparin and other drugs are used for this, but great care must be taken when prescribing them (there is a possibility of internal bleeding).

The heart is one of the most vulnerable organs. It is not surprising that in modern society- at bad ecology and the emergence of low-quality food, aortic stenosis occurs in dogs much more often than before. At timely application you can see a veterinarian-cardiologist to get rid of negative manifestations diseases and prolong the life of your pet.

Symptoms of aortic stenosis

1. Poor appetite, apathy, weight loss/weight gain.
2. Dyspnea.
3. Short-term loss of consciousness.
4. Cough after active movements (in the absence of colds).
5. Increased thirst.
6. Breathing with open mouth in room.
7. Blue tongue.
8. Loss of coordination.
9. Anxiety.
10. Sudden increase in abdominal volume.

With aortic stenosis in dogs, several symptoms from the list are observed. If you find any of the signs listed above in your pet, you should immediately contact a veterinary cardiologist. The most dangerous symptom is a blue tongue. In this case, you should immediately call an ambulance veterinarian.

How can you help at home?

Provide four-legged friend complete peace. Open the window and offer a drink. Do not try to force feed your pet under any circumstances - otherwise you will end up vomiting.

Don't try to study self-treatment. Folk recipes are absolutely pointless if aortic stenosis manifests itself, and medications that have not received the doctor’s approval can cause irreparable harm.

What can a doctor do?

Initially, the cardiologist will conduct a detailed diagnosis, which includes:

1. Clinical examination.
2. Taking tests.
3. Echocardiography.

After receiving the results, the cardiologist will determine his further actions. Most often used to treat aortic stenosis drug therapy. In some cases, surgery is indicated.

Aortic stenosis in dogs today does not pose such a danger as in the old days. With the participation of a competent cardiologist, positive dynamics can be achieved. Make an appointment at our clinic - and you will take the first step towards recovery for your four-legged friend.

In which breeds is the disease more common?

Causes and contributing factors of tracheal collapse

Risk factors include obesity, infectious diseases respiratory tract, obstruction of the upper respiratory tract.

Diagnosis of tracheal collapse in dogs

Whistling or musical rales are heard above the trachea. When a large section of the trachea collapses, a click is heard at the end of forced expiration. Damage to the cervical trachea is accompanied by inspiratory shortness of breath, and with collapse of the thoracic region, expiratory shortness of breath is noted. Disease of the lower respiratory tract is manifested by corresponding symptoms.

It is worth differentiating tracheal collapse in dogs from:

• congestive heart failure:
• laryngeal paralysis;
• tumors;
• pneumonia;
• tumors or foreign body in the trachea;
• neoplasms in the mediastinum of the neck;
• acute bronchitis;
• bronchiectasis.

Laboratory and instrumental diagnostic methods

In 60% of cases, tracheal collapse is detected by radiography (on inspiration - collapse of the cervical spine, on exhalation - collapse of the intrathoracic region). Collapse of the main bronchi and swelling of the cervical trachea can also be detected. There are often signs concomitant diseases: bronchitis, pneumonia or bronchiectasis. With chronic lung damage, an enlargement of the right chambers of the heart is sometimes observed, but in animals of some breeds anatomical features prevent you from clearly seeing the shadow of the heart. In dynamics, collapse of the trachea and/or its membranous part can be seen during fluoroscopy, and it is advisable to induce a cough in the patient.

Bronchoscopy distinguishes 4 degrees of severity of tracheal collapse in dogs and diagnoses lower respiratory tract disease. With grade 1 collapse, almost normal tracheal muscles slightly sagging into the lumen are observed. In grade 2, the narrowing of the tracheal lumen does not exceed 50%. With grade 3 collapse, the lumen decreases to 75%, and the muscles almost touch the tracheal cartilage. With grade 4 collapse, the cartilage becomes flat; less than 10% of the lumen is preserved; when the muscles contact the ventral surface of the trachea, a double lumen can be observed. During bronchoscopy, material is taken for bacteriological and cytological studies.

Treatment and emergency assistance

It should be borne in mind that ketoconazole and phenobarbital enhance the metabolism of theophylline, and fluoroquinolones, erythromycin, cimetidine, beta-blockers, steroids, mexiletine and thiabendazole weaken it. A reduction in the dose of the drug is required for congestive heart failure, chronic pulmonary heart and liver diseases.

Surgery in the early stages with and without primary collapse of the cervical trachea pronounced changes in the lungs, performed by an experienced surgeon, can improve the condition of the animal.

Follow-up