Chicken “Snuffles” aka respiratory disease.

Respiratory disease often presents itself with one or more birds sneezing/snicking or wheezing/coughing. These birds can have a runny nose and foamy running eyes. In severe cases these birds can have swollen sinuses (presents as swelling around the eyes), stop eating and in extreme cases unfortunately die.

Coughing in birds normally sounds different to what you’d hear in a human due to their anatomy. It often sounds more like a honk or a high pitched squeak, you’ll often see the bird extend its neck out during the sound. In most cases its due to a build-up of mucous in the airways.

Respiratory disease in chickens has a range of causes ranging from viral to bacterial and less commonly parasitic, fungal and allergic. Many of these present with very similar signs so an accurate diagnosis cannot be made via clinical history and physical examination alone.

If your bird does develop any of the above signs it is worth consulting a vet as antibiotic treatment is sometimes needed. If the cause is viral in most cases supportive care and time is enough to settle (use of home remedies can sometimes be adequate).

If the bird is not improving however, there may be a bacterial component that needs addressing and antibiotics will be required. In general, your vet will often advise that all in contact birds be treated as most respiratory diseases are very contagious by nature. Usually, medication is given via drinking water for large groups but in severely ill birds, or small numbers, injections or daily dose tablets may be the best to ensure adequate dosing.

Birds suffering with respiratory disease should always be isolated from healthy stock to limit spread of the disease, given lots of TLC and veterinary attention when necessary.

Cause

There are a number of predisposing factors for respiratory disease in chickens: as with any animal, stress can cause an underlying disease to show itself. This stress could be extreme temperatures and humidity, high stocking density, being transported, being taken to a poultry show and new animals being introduced to an existing/established flock. Concurrent disease such as coccidiosis and worm burdens can weaken an animals immune system making them more susceptible as can inadequate nutrition.

There are a number of possible pathogens involved in respiratory disease in chickens. If you are having constant issues in your flock, it is possible to test for most of these and work out a treatment/prevention plan. It is often the case that more than one pathogen is involved, the most common ones being Mycoplasma gallisepticum, Infectious Bronchitis and ILT (Infectious LaryngoTracheitis virus).

Mycoplasma Gallisepticum

Mycoplasma Gallisepticum is a type of bacteria which can cause respiratory disease in chickens and other poultry. It is often associated with swollen sinuses, sneezing and foamy watery eyes. In certain cases, it can cause swollen joints and subsequently lameness. It can infect the oviduct, thus altering egg shell colour and quality and therefore it can be transferred via the egg to chicks.

Once infected a chicken is infected for life although clinical signs will regress with time and treatment, but they are always liable to come back. This organism is generally involved in chronic respiratory disease CRD.

Infectious Bronchitis

Infectious Bronchitis is a coronavirus which causes sneezing, foamy eyes, and swollen sinuses usually in young birds. Like Mycoplasma it can infect the oviduct again altering egg shell colour and quality but unlike Mycoplasma it does not infect chicks via the egg, so separation of young chicks from adults can help reduce infection rates. Severe IB infection in young female birds can permanently damage the oviduct causing it to permanently not carry the yolk from the ovary to the oviduct so the eggs are laid internally.

These eggs inside the bird ARE slowly absorbed but they provide an excellent food for bacteria, so internal layers are vulnerable to get egg yolk peritonitis. If the absorption rate is slower than the speed that she continues to lay eggs internally, this can result in a build-up of yolks in the chicken’s abdomen, causing her to adopt a penguin like stance and difficulty breathing.

Infectious LaryngoTracheitis Virus

Infectious LaryngoTracheitis Virus is a herpes virus and causes similar respiratory signs. ILT often leads to a plug of blood and mucus which can block the chicken’s trachea (windpipe) leading to the bird choking to death. This virus tends to cause more mortality, versus morbidity, than many of the other disease agents. Like Mycoplasma, it never goes away and birds that recover from an initial attack can suffer repeat bouts of disease during times of stress. These birds are also a continual source of infection for other birds.

Respiratory system

One of the things that sets birds apart from mammals is their respiratory system.

They are incredibly efficient at obtaining oxygen from the air to feed their high metabolisms, but their very anatomy puts them at increased risk of attack by pathogens or air quality issues.

They have air sacs which are very thin membranes with a very poor blood supply and when viruses such as IB damage the protective cells of the trachea (windpipe) the birds can easily breathe in bacteria which can cross the air sacs into the abdomen to cause peritonitis.

Fungal spores or bacteria that are breathed into the air sacs can easily grow in the warm humid environment and can be difficult for a bird’s immune system to overcome due to the poor blood supply of the area. Air Sacculitis is a common sequelae, and often fatal due to a build-up of pus unless diagnosed early.

Birds have evolved in most cases to live in large open areas which reduces contact with infectious organisms and spores. Ensuring good ventilation of housing is paramount to a chicken’s long-term health as well as regular cleaning of the coop to reduce numbers of infectious organisms. Any damp areas will also encourage the growth of fungal spores.

Prevention

The best way of preventing infection of your birds is to minimise stress, ensure the stocking density and ventilation are correct and that you quarantine any new birds for at least 2-3 weeks. Anything that develops respiratory issues in this time should not be added to your flock.

If you breed your own birds and you have any ongoing disease issues you can consider vaccination. There are a range of vaccines available, the most relevant one for NZ breeders is for infectious bronchitis.

The initial vaccine course comprises of three doses administered a month apart to young birds, either, by spray or drinking water with a final injection at 16-18 weeks that provides good immunity for the next 18 months.

There is a vaccine for ILT, though this disease is generally found more in the northern regions than the south.

There is lots of information on the Pacific Vet website about the different diseases in NZ and available treatment options. Most are geared towards commercial operations and come in 500-1000 dose vials and unfortunately need to be used within 1-4 hours of being made up. This does make it difficult and more costly for smaller breeding operations, but it can be economically viable for breeders hatching out more than 50 at a time.

Treatment

As many of you will notice, the pathogens mentioned are mostly viruses which will not respond to antibiotics. However, these viruses often damage the respiratory system sufficiently to allow secondary bacteria such as E. coli and Pasteurella to cause infection and in severe cases blood poisoning.

Bacterial infections will need antibiotic treatment from your Vet. Antibiotics by law need a relevant consult within 6 months to be dispensed, with repeat dispensing at the discretion of your veterinarian. Developing a relationship with your veterinarian will help greatly in obtaining medications when you need them.

If your birds are being stressed by bad weather or moulting etc, you may want to consider supplementing them with multi vitamins or probiotics. Both these products will give your birds a boost which will be invaluable to helping them resist disease or recover.

At home remedies include adding garlic and turmeric to the feed, there is evidence to support the use of oregano oil which contains natural antibiotic properties. We have also found dabbing a small amount of Vicks on the beak in front of the nostrils can be helpful to clear congested sinuses and open the airways.

Sick birds ideally need to be kept in a quiet warm environment until fully recovered.