Updated: Nov 15, 2019
Every farmer knows the devastating effect of diseases on the farm. Diseases causes loss for the farmer and if not managed properly can lead to a spread affecting a community of farmers. The good news about diseases is they can be prevented and controlled with the right information.
In the next 6 weeks, we will be sharing about some common diseases in poultry. We will discuss their causes, symptoms, transmission, treatment and prevention. We trust at the end of the 6 weeks, you will be able to manage your farm against diseases.
This week, we are looking at the Newcastle and Avian Influenza (Bird flu) diseases.
Newcastle disease is probably the most important disease for poultry farmers around the world. This is a production disease that causes many deaths in chickens and huge losses to farmers and the industry. Because there is no treatment and the disease spreads so quickly, sick chickens should be slaughtered immediately
Causative Organism: This disease is caused by a virus.
Many chickens will die suddenly without any of the following apparent causes:
Sneezing, swollen eyes, difficulty in breathing
There is NO treatment for the disease and all the chickens may die within a few days. Very
few chickens survive.
It is best to prevent the diseases by good management and a vaccination programme.
Your animal health technician or veterinarian will give you the best advice in a Newcastle disease outbreak, especially as this is a controlled disease.
You should vaccinate all the chickens against this disease by using a good vaccination programme before any signs appear.
It is a very contagious disease, which means it spreads easily to other farms. You should not visit your neighbours without washing and putting on new clothes and shoes. You should also recommend that your neighbours vaccinate their chickens as soon as possible.
You should clean the chicken house thoroughly with soap and water. All equipment must be washed. Everything should then be disinfected.
You should also wash and disinfect your clothes and shoes. All chicken litter or dead chickens should be burned to prevent the spread of the disease.
Avian influenza is categorized as low (mild) or highly pathogenic. The low pathogenic form (LPAI) produces listlessness, loss of appetite, respiratory distress, diarrhoea, transient drops in egg production, and low mortality.
It is characterized by a sudden onset, massive morbidity and mortality over a short period of time.
It causes facial swellings, blue combs and wattles, diarrhoea, respiratory distress and sometimes nervous disorders.
Dark red/white spots develop in the legs and combs of chickens.
There can be blood-tinged discharge from the nostrils.
Loss of appetite and diarrhoea.
Egg production and hatchability decreases.
There can be an increase in production of soft-shelled and shell-less eggs
Causative organism: Avian Influenza is caused by Type A Influenza virus.
Avian Influenza is transmitted by direct contract.
Direct contact of wild birds with free range birds is another important factor in the spread of AI.
It is also spread on the farm and between farms by contaminated farm equipment, feed bags, egg crates, vectors such as rodents and insects, and contaminated shoes and clothing.
The avian influenza virus can remain viable for long periods of time at moderate temperatures and can live indefinitely in frozen material. As a result, the disease can be spread through improper disposal of infected carcasses and manure.
There is no effective treatment for avian influenza. With the mild form of the disease, good husbandry, proper nutrition, and broad-spectrum antibiotics may reduce losses from secondary infections.
With the more lethal forms, strict quarantine and rapid destruction of all infected flocks remains the only effective method of stopping an avian influenza outbreak. If you suspect you may have Avian Influenza in your flock, even the mild form, you must report it to the veterinarian's office. A proper diagnosis of avian influenza is essential.
Strict biosecurity procedures should be practiced.
Direct or indirect contact of susceptible birds with waterfowl, shorebirds and birds or poultry products from endemic AI areas must be avoided.
In our next post, we will be sharing about the Fowl pox and Egg drop syndrome in birds. See you then.