One of the most common and potentially devastating viral respiratory diseases that threatens your operation is Pox. There are two types of Pox – dry and wet. Both can damage your flock if not treated properly. Generally, both spread steadily but slowly giving you time to react when you first spot the symptoms. These viruses are usually spread by insects, mainly mosquitoes and flies or by bird to bird contact. When contracted, Pox will cause a decrease in performance whether that is egg production, meat production, breeding or showing. Although incurable it can be prevented and controlled by vaccination, disinfection, and practicing good biosecurity. Unfortunately, both viruses can be contracted simultaneously. These diseases are also known as: chicken pox (not like the human kind), sore head, Pigeon Pox, Canary Pox and avian diphtheria.
The Dry Pox virus causes raised lesions, similar in appearance to warts, to occur in un-feathered areas such as the head, vent, comb, wattle, ear lobes and legs. Weak and/or stunted birds are the result if left untreated. These lesions will heal within 2 weeks so careful attention is needed to spot Dry Pox. Just because you can no longer see it, it will continue to infect and spread. This condition is very painful but the bird rarely dies.
Transmission of Dry Pox occurs when the virus enters the blood stream after coming into contact with exposed areas such as eyes, inhalation and open wounds. Mosquitoes, the primary villain in the transmission of Pox, means you must have effective mosquito control practices. Mosquitoes often over-winter within your fowl housing unit and re-infect the flock the following spring, all the more reason for a good insect control program. Under certain conditions, the Pox virus can even “live” outside a host for months at a time. Regular spraying, dusting and disinfecting are critical to prevention and control of the disease. The good news is that healthy skin is usually an effective barrier to this disease so implementing good nutrition increases your bird’s natural resistance levels.
Wet Pox occurs internally and cannot be seen without surgery. It can definitely be heard because it a cankerous growth primarily in the mucus membranes of the trachea, mouth, larynx and pharynx which develops obstructions in the air passages. This is why Wet Pox has a high mortality rate. Fortunately, Wet Pox is rare. Transmission is the same as with Dry Pox and the same control techniques should be used. If infected, add vitamins and amino acid supplements to the water to help prevent weight loss and to compensate for decreased appetite.
Vaccines can be used to control the disease by preventing infection but cannot help after infection has occurred. Vaccines should be used if there is a history of infection or if your location is exposed to mosquitoes year round. Some recommend vaccinating twice a year, in the spring and fall. However, if you plan to implement a sound prevention program you should minimally consider vaccinating chicks at 1 to 3 days old. A professional program would include permanent protection by vaccinating at 8 to 10 weeks with a chick embryo origin (CEO). This works to ensure long term protection.
In the event of an outbreak of Wet Pox, administer a combination of Pigeon Pox vaccine and Fowl Pox vaccine with dosages of 1.25 per bird. Administer a second time 2 to 5 weeks later. This combination stimulates a broad-spectrum immune response that will minimize your mortality rate. Mix vaccines together and administer in the wing-web.
Buying fowl from reputable sources, closely inspecting the fowl before purchasing and quarantining new birds are a key element in preventing the introduction of Pox into your operation. We should always remember that stress-free birds are less likely to contract any infection so keep them happy!
Cleanliness and disinfecting, reducing exposure, monitoring and recording, all play a crucial role in preventing these and many other diseases. Because these Poxes are transmitted by outside sources the threat of exposure never goes away so be vigilant – it pays off in increased performance.