Improved kienyeji chicken breeds in KALRO, Kakamega. [Mumo, Munuve, Standard]

Have you ever noticed a swollen eye in your chicken? In some cases, either eyes or an eye is completely closed and full of pus. You may wonder, what is the cause? How can I treat it? And if there is any control measure you can institute in your farm? I will address all these concerns in this article.

What is swollen eye syndrome?

This is a chronic and complicated upper respiratory infection, which starts with sneezing, coughing, tearing or wet eyes and mild inflammation of the eyes (conjunctivitis). If this condition is not treated immediately, there will be swelling of the infraorbital sinuses, especially in complicated cases and the eyeball will be filled with pus. It can affect one eye or both. Where both eyes are affected, the chickens fail to locate feed and water and are likely to die of starvation. What conditions or diseases contribute to swollen eye syndrome?

  1. Poor ventilation

Poor ventilation and a stuffy dusty environment can also cause a sudden increase in upper respiratory infections in chickens. Ensure that the chickens always get fresh air. Open curtains to remove any buildup of dangerous gases during the day and night. Carbon dioxide levels should never exceed 2,500 ppm while ammonia levels should be below 20 ppm. If you find yourself shedding tears in a poultry house full of wet litter, know that ammonia levels are running high. To avoid such scenarios, remove any wet litter and replace it with dry friable wood shaving. Make it a habit of turning your litter once per day.

  1. Avoid dusty feed or litter

Most of the feed in the market for birds is made of small-sized particles that if inhaled during feeding time will cause irritation of the mucosal surface of the upper sinuses resulting in coughs and difficulty in breathing. In addition to that, there will be reduced feed intake and low nutrient absorption. This leads to poor performance in the long run. Check your feed using a sieve shaker and discuss with your miller for a more coarse diet.

  1. Contaminated drinking water

Water is the single most important nutrient in the life of any living animal and yet it is the most likely to be ignored in livestock production systems. Provide fresh, clean, portable water, free from disease-causing organisms. Contaminated water with E. coli or coliforms can be a leading cause of respiratory infection in poultry. Make sure that your water is treated with chlorine tablets at least once a week. To avoid the buildup of biofilms in the water lines, it is important that the water pipes are flushed with hydrogen peroxide periodically.

  1. Early bacterial or viral infections

Other diseases which can cause similar clinical signs include Mycoplasmas, Newcastle disease, Infectious Bronchitis, Coryza, E. coli, Aspergillosis, the list is long. It is important that a veterinarian near you is contacted to make a flock appraisal and probably do a physical examination. A complete flock history and interrogation of animal husbandry practices like feeding space, flock density, water consumption, vaccination history, biosecurity levels, environmental hygiene levels, pest and rodent control will be required to rule out any early infection. Note that live vaccinations against diseases like Newcastle, infectious bronchitis and Gumboro may elicit upper respiratory reactions and birds will show similar clinical signs without responding to any antibiotic treatment.


A qualified vet should be contacted to examine the whole flock and do a root-cause analysis. Severely affected birds should be culled to avoid prolonged suffering. Flocks should be vaccinated against prevalent diseases without fail. Any further antibiotic treatment can only be done after a laboratory-based diagnosis by a qualified vet. Any antibiotic application will need a veterinary prescription. I have traditionally squeezed the affected eyes and applied topical antibiotics. Affected birds should be penned-off and supplied with plenty of feed and water.

[The writer is the Head Vet at Kenchic,]