Franco recently sent me an email to ask what medicine he should use for a cough in a dog. Franco is the animal assistant at The Big Fix in Uganda where I volunteered for a week last fall. Franco and Dr Arnold and I have kept in touch about cases since I came back. Things are very different in Uganda and I suspect that Dr Arnold was out in a remote village doing vaccines, spays and neuters and Franco was left at the hospital and trying his best.
Unfortunately, I was not as much help to Franco as he had hoped. The problem is that coughs are not the problem, they are a symptom of the problem. Yes, we have cough suppressants, but that only covers up the cough, not the source of the cough.
I replied that coughs can be caused by a number of things. Parasites can cause coughs. Hookworms and roundworms are gotten from the ground. Tiny larva burrow through the skin on the feet or through the cheek when they are licked into the mouth. From there they go through the skin and muscles until they end up in the abdomen. Not in the intestines yet, but the abdomen. There they burrow through the liver (sometimes you can see parasite scars on the liver of cows or pigs at the market), up through the lungs and then they are coughed up from the airways and swallowed into the intestines. By the time they are being coughed up and swallowed, they are no longer microscopic. As far as I know, I have never coughed up a worm, but I cannot imagine that it is fun. Coughing would be significant. Heartworms also have a cough associated with the disease. Either the right heart enlargement causes problems or the heart failure does.
Dogs can also have pneumonia. A bacteria or virus can get into the lungs and cause inflammation and fluid. I saw this once on a dog sled race in Montana. A team came in and was checked by another vet. As I was walking by the line of dogs bedded down in the straw, I noticed a couple had elevated respiration rates. The soft cough could barely be heard on the silent starry night. That almost silent cough was a dangerous sound though. The dogs had picked up a viral or bacterial pneumonia. They were sick and would not run well. If the musher had left the checkpoint, he would have turned around and scratched (musher lingo for quit). As it is, we took 4 or 5 dogs out of his team and treated them with IV fluids and antibiotics. He wasn’t thrilled with me as I took half of his team, but the remaining dogs ran fast and brought him in for a first-place finish.
A lower respiratory infection is pneumonia like the sled dogs had. The upper respiratory cough is a sinus or tracheal infection or irritation. Kennel cough in dogs is a bacterial damage to the trachea that can take weeks to months to heal. A tracheal cough can be induced by pressing on the trachea. Too much pressure on a collar can cause a tracheal cough.
Heart problems can also cause a cough. Either the heart enlarges as it tries harder and harder to work and then pushes on the bronchus to cause a harsh cough like the tracheitis cough of kennel cough. When the heart gets weak enough that it cannot keep up with the pumping of the blood, fluid starts to leak out into the tiny air sacs of the lungs. These alveoli know that they are not supposed to have fluid and then a cough starts to get rid of the fluid. When the animal (or person) is up and about, the muscles of the body help move the blood throughout the body. So a cardiac cough is often found in the middle of the night. It is the one cough that will wake up the pet (and owners).
The lungs have air, so fungus can be found growing in them. Histoplasmosis and blastomycosis are found in buildings were vermin have left feces or guano to grow. Mammals can often fight off the disease but may have permanent damage. Birds on corn cob bedding will grow Aspergillus in their air sacs. African Greys and raptors are especially susceptible to dying of aspergillus.
Franco, you have to get to the cause of the cough. Is it from the lungs? If you cup your hands and thump the chest (couphage), it will knock some of the growth into the sacs and cause the dog to cough. Or is it a tracheal cough that you can hear when you push on the tracheal. Is it a nighttime cough or activity cough? Are any other animals sick? Is this animal sick?
In the end, I wasn’t able to help Franco in the time he needed. There were too many variations of what a cough means. I wasn’t able to help him then, but perhaps this can help him. Every time, you need to know more.