Swelling head disease in chickens is an indicator of Coryza, a rapidly spreading illness in poultry if not detected early. In this article, Mebipha provides information on Coryza in chickens, including treatment methods and effective prevention strategies.
Causes of Swelling Head Disease in Chickens
Swelling head disease, also known as Coryza or infectious coryza in chickens, is an acute respiratory disease that can occur year-round and on a large scale. The disease is caused by the aerobic bacterium Haemophilus paragallinarum (also known as Avibacterium paragallinarum). In the natural environment, this bacterium can survive for 2-3 days and is most commonly found in concentrated poultry farms, especially in egg-laying hens.
The disease spreads rapidly and causes decreased feed intake in chickens. The mortality rate from Coryza typically remains below 5%, but if not treated effectively, this figure can increase. Chickens of all ages can be affected by Coryza, with older chickens experiencing more severe illness. The disease is prevalent in 90% of chickens at 4-8 weeks of age and in 100% of chickens at 13 weeks and older. Coryza spreads from infected to healthy chickens primarily through respiratory and digestive routes via contaminated feed and water.
Symptoms
The incubation period for Coryza is short, ranging from 1-2 days, with symptoms appearing in all chickens within the flock within a week or 10 days. The disease usually progresses over 14-21 days by Thanhga.
Symptoms of Coryza in chickens include:
- Nasal discharge, watery eyes, and swelling of the head, face, and wattles.
- Inflammation with discharge from the nose that later thickens into white, hard mucus and bulges on both sides of the nose.
- Eye discharge, conjunctivitis causing eyelids to stick together, resulting in limited vision.
- Reduced egg production in layers by 10-40%, decreased feed intake, ruffled feathers, discomfort, and restlessness.
Treatment
Coryza spreads quickly horizontally, so even after treating the affected chickens, the bacteria can still infect healthy birds. Therefore, it is crucial to isolate sick chickens and enhance disinfection in the poultry house to eliminate pathogens. Effective treatment regimens for Coryza include:
- Morning: Use CEFTI ONE + ALPHA TRYPSIN WSP + BROMHEXINE for 5 days. Afternoon: Use AMINO PHOSPHORIC for 7 days.
- Alternatively, Morning: Use AMOX WSP + ALPHA TRYPSIN WSP + BROMHEXINE for 5 days. Afternoon: Use AMINO PHOSPHORIC for 7 days.
Preventive Measures
Coryza can occur year-round, so poultry farmers should focus on prevention and maintaining the best health for their flocks. Recommended preventive measures include:
- Regular cleaning, disinfection, and sanitation of poultry houses to prevent pathogen buildup.
- Disinfecting after each flock and allowing the house to remain empty for a period before introducing new birds.
- Vaccinating chickens against Coryza to proactively prevent the disease.
- Ensuring safe feed and clean water for the flock.
Treatment for Chickens with APV Combined with Other Diseases
Since APV (Avian Pneumovirus) is a virus, no medication can eliminate the APV pathogen from the chicken’s body. Antibiotics can only help control secondary infections. In most cases, chicken deaths are caused by secondary infections rather than APV itself. APV often combines with bacteria such as E. coli, Bordetella (whooping cough), Pasteurella, Pseudomonas (green pus bacteria), and ORT. If chickens show signs of reduced feed intake, lethargy, ruffled feathers, swelling of the head, face, and eyes, and mucous discharge, but do not respond to Coryza treatment, they may be infected with APV. In such cases, follow these steps:
- Step 1: Isolate all sick and lethargic chickens in a separate area to facilitate care and monitoring, ideally as far from the main poultry house as possible.
- Step 2: Clean all poultry equipment thoroughly. Sanitize and disinfect the entire area inside and around the poultry house.
- Step 3: Treat symptoms based on the secondary infections causing the observed symptoms. Choose appropriate medications and methods to address these symptoms.
- Step 4: Administer broad-spectrum antibiotics to the isolated chickens and mix (or dissolve) powdered antibiotics into the feed (or drinking water) for the entire flock. Recommended antibiotics include Amoxicillin combined with Doxycycline. Each treatment cycle should last about 3-5 days to avoid overexerting the chickens.
- Step 5 (to be done concurrently with Steps 3 and 4): Enhance the chickens’ resistance by administering detoxification and liver-kidney supplements, Vitamin ADE, Vitamin C, and digestive enzymes.
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Conclusion
Swelling head disease (Coryza) in chickens is a highly infectious disease that can cause significant economic losses to poultry farmers. Mebipha has outlined effective treatment protocols and preventive measures for managing Coryza. Implementing these preventive strategies will help minimize economic damage and maintain the health of your poultry.
