In all types of cough, it is a reflex activity aimed at clearing irritating or foreign materials or infectious agents from the airways. Receptors present in the airway walls detect the presence of such material and initiate strong, reflex contractions of the diaphragm and abdominal muscles, while increasing the pressure of leakage through the larynx, leading to forced expulsion of mucus and debris from the lungs and airways.
Cough is a normal protective bodily function, but when it is persistent or severe or is accompanied by signs of a systemic illness such as fever, inadequacy, or loss of exercise tolerance, this can be an indicator of a serious problem.
What are the causes of cough in dogs?
The causes of persistent cough can simply be divided into two types: primary respiratory and cardiac ( heart- related) cough. In some scenarios, both types can coexist, which can obviously make them difficult.
Infectious respiratory disease in dogs
The most common type of respiratory disease seen in veterinary clinics is infectious tracheobronchitis , commonly known as ‘cinnamon cough’. Affected dogs have a persistent or paroxysmal strong, sharp cough that may or may not be followed by the production of frothy mucus. Owners often mistakenly think that a bad dog has something stuck in its throat or that the dog is suffocating. In fact, the severe nature of the cough is due to inflammation of the walls of the trachea and bronchial tree, usually without significant respiratory damage. Whooping cough in dogs usually does not cause generalized signs of disease, except in very young, very old or otherwise disabled animals.
There are several infectious organisms associated with infectious tracheobronchitis, one called Bordetella bronchiseptica, which is responsible for most cases. Vaccines are available against this disease and you should certainly consider whether this should be included in your dog’s vaccination schedule if he / she is in regular contact with other dogs, whether or not he is bred.
Вашият ветеринарен лекар може да избере да използва курс на антибиотици в зависимост от тежестта на кашлицата на вашето куче, а понякога се използват и средства за потискане на кашлицата, като кодеин, тъй като кашлицата може да бъде толкова тежка, че да попречи на вашия домашен любимец (и себе си!) Да спи, обаче супресант за кашлица никога не трябва да се използва без съветите на вашия ветеринар, тъй като понякога те могат да изострят основната инфекция, като предотвратяват клирънса на бактерии от дихателните пътища. Насърчаването на вашето куче да вдишва парна пара, като го отвеждате до банята и пускате душ или давате лъжица мед са две естествени и безопасни средства, които можете да опитате у дома.
Infection of the lower respiratory tract ( bronchitis ) or lungs ( pneumonia ) tends to produce more severe signs of illness and most dogs will be depressed due to septicemia or fever. The cough in these cases is usually milder than that heard with a cinnamon cough and you may notice an unpleasant odor from your dog’s breath. Bacterial and fungal infections are usually associated with infections at these lower levels of the respiratory tree and they usually require more aggressive treatment by your veterinarian.
Parasites such as Oslerus osleri , lung and heartworm can cause coughing through various mechanisms. Parasitic infection is worth considering as a possible cause if your dog has not recently received a deworming dose.
Non-infectious respiratory problems
As we all know, dust, smoke and other irritants can cause coughing. Again, this is normal, but chronic exposure can cause secondary changes in your dog’s airways, leading to excessive mucus production, thickening of the airway walls, loss of normal elasticity and hypersensitivity. Allergic pneumonitis is a condition that can cause a severe respiratory compromise in dogs and should be managed by identifying and removing the allergen, if possible, and with prednisolone (a steroid) or other drugs to suppress the immune response.
Chronic bronchitis is a common condition in older dogs (most commonly small breeds such as terriers), which causes a productive cough with wheezing. It is much more common in homes where the pet is exposed to cigarette smoke. Again, treatment usually requires the use of steroid medications, and bronchodilators may also be helpful in some cases.
Tracheal failure is a condition of the upper respiratory tract that can sound a lot like a cough, as a dog with a cough will probably be very well with a sharp, strong cough. It is caused by a weakness in the wall of the main airway (trachea) and is often aggravated by agitation, environmental irritants or pulling lead. This is an anatomical abnormality that occurs in small and pedigree breeds such as the Yorkshire Terrier, and treatment in some cases requires the implantation of a stent in your dog’s airway. Weight loss can be very helpful in mild cases in obese patients.
Tumors in the breast can cause coughing if they invade the airways or cause fluid to build up. The lungs are a common site for secondary tumors that arise from primary masses elsewhere in the body.
Cough as a result of heart disease in dogs
Cardiac cough in dogs is usually caused by a disease of either the heart muscle (cardiomyopathy) or the heart valves, which promote normal blood flow through the heart, preventing backflow and congestion. Dogs with a cardiac cough often show other signs of poor circulation, such as intolerance to exercise, fainting, or lethargy. Congestive heart failure is the result of blood coming together in the venous system and fluid leaking into the lungs and body cavities, as well as coughing, some dogs with congestive heart failure will have a swollen abdomen filled with fluid.
There are well-known predispositions for breeds to these heart diseases; for example, Doberman Pinschers and Cocker Spaniels are prone to developing dilated cardiomyopathy (DCM), while smaller breeds, especially Cavalier King Charles Spaniels, are much more at risk of developing valvular disease.
Both classes of heart disease cause secondary changes in the chambers of the heart, leading to enlargement of the heart. In addition to a mild cough caused by fluid retention in the lungs, this enlargement of the heart also causes a simultaneous severe cough, as the larger chambers, especially the left atrium, compress and irritate the large airways, which means that the type of cough can varies in dogs with heart failure.
With the advancement of medical and surgical treatment, heart disease in dogs has become a very treatable condition in many cases, and your veterinarian will discuss the most appropriate treatments for your pet.
Ultrasound examination of heart disease
Diagnose the cause of your dog’s cough
As I said above, unless your dog is very well, despite his cough, he should be taken to your veterinarian for an examination. In some cases, your veterinarian may be happy to diagnose and prescribe treatment based only on the findings of a physical examination, but in some cases, for example in an older dog of a small breed with signs of both heart disease and of chronic bronchitis, further examination is probably reasonable to determine the best course of treatment.
Full blood work usually does not give a diagnosis, but it can be important to ensure that prescribed medications will not be harmful to your dog. For example, much older dogs with heart disease will also have some degree of kidney failure, which requires great care in choosing the type and dose of medication used.
Your dog’s chest x-rays provide a lot of useful information about the condition of the lungs and airways, as well as an assessment of the size, shape and position of the heart. Ultrasonography is a great non-invasive technique for examining the soft tissue structures in the chest, but mostly in the heart, and allows real-time view of the movement and contractility of the heart chambers. Bronchoscopyis placing an optical cable down the airway. It needs to be performed under general anesthesia, which can obviously carry some risk, but it is the most useful way to examine the inside of the airways and allows the collection of samples for bacterial and parasitic tests, and can also help identify of tumors in the lungs and bronchi.
What to do if your dog coughs
In most cases, a dog that has a persistent cough should be examined by a veterinarian. If you have a healthy young dog that has just started coughing and shows no other signs of illness, then you may be able to breastfeed through it using steam and home remedies, as shown above. If in any way you are not sure what to do, please call your local surgery for advice.
Let me know in the comments below if there are any additional tips you would like to see (non-urgent questions only).