Use Sulfonamides with Caution When Treating Infectious Coryza in Chickens

The pathogen of infectious coryza in chickens is Haemophilus paragallinarum, and it is an acute upper respiratory tract disease with highly contact-based transmission. The disease tends to become epidemic in humid seasons, mostly occurs as mixed infections, and the incidence rate is high in adult chickens.

Symptoms: nasal discharge, which forms scabs after drying and blocks the nostrils. Facial swelling, with swelling on one side of the face in most cases, head shaking, closed eyes and listlessness, preference for lying down, reduced feed intake, decreased egg production, and greenish watery droppings. Some chickens show respiratory symptoms such as coughing and sneezing.

Treatment: Sulfonamides are highly effective, but they inhibit egg production, so they should be used with caution in laying hens; if equal amounts of baking soda (sodium bicarbonate) are used together, the toxic side effects can be reduced. There are many drugs that can treat coryza in chickens, such as Gaolimixian, ciprofloxacin, and Biyanke, but recurrence is easy after recovery, it is difficult to eradicate completely, and the treatment course is too long. A combined therapy of Chinese and Western medicines can be adopted, with a relatively large dosage, and the effect is significant. For example, use the Chinese herbal medicine Xinyi (biond magnolia flower bud), 2 grams per adult chicken per day; Canger (Siberian cocklebur fruit), 1 gram per adult chicken per day, decoct in water and give as drinking water, combined with tylosin, dissolving 1 gram in 10 kg of water, once daily, for 5 consecutive days. It should be noted that if an outbreak of coryza has already occurred in the flock and the incidence rate is less than 1%, infectious coryza vaccine can still be administered at this time; if the incidence rate exceeds 5%, infectious coryza vaccine must not be administered, in order to prevent worsening of the epidemic and the occurrence of mass chicken deaths.