Poultry birds and poultry production are generally affected by seasonal climatic or weather changes. For instance, in the wet or cold season, chickens eat more feed, drink less water and huddle together to generate heat and keep themselves warm. On the other hand, chickens and other livestock birds consume less feed and drink more water in the hot season or weather in order to cool their body.
Don’t be surprised that these changes affect the production of birds, most especially laying birds, as the egg production is reduced in extremely cold or hot weather. This reduction in egg production occurs because when there are extreme cold or hot conditions, these birds are stressed, and their ability to withstand diseases or immune system is seriously affected.
Some certain poultry diseases are rampant in the wet, rainy or cold seasons. That is, the onset of rain favors the propagation and spread of the causative organisms of these diseases and parasites. Hence, most poultry farmers experience high morbidity and mortality rate during this period. We’re going to discuss some of the poultry diseases that are highly prevalent or rampant in the wet, cold or rainy season.
1. Gumboro or Infectious Bursal Disease (IBD)
Gumboro disease is a virulent disease that affects chicks and young birds between 3-18 weeks of age. The causative virus attacks the bursal of a bird thereby suppressing or weakening the immune system and predisposing the birds to secondary infections.
Signs of Gumboro diseases or IBD
- Severe prostration
- Watery diarrhoea
- Incoordination
- Inflammation of the cloaca
- Soiled vent feathers
- Vent picking
Treatment, Prevention and Control
Gumboro disease is highly contagious and a flock owner should expect as high as 100% morbidity rate and a 20% mortality rate. This disease has no cure or treatment but it can be prevented through vaccination of birds before an outbreak occur. In a situation where the disease has already occurred within a flock, the flock should be culled and the pens should be disinfected. Gumboro Infectious bursal disease vaccine (IBDV) should be administered to chickens at their 2nd week and 4th week of age.
2. Fowl Pox
Fowl pox is a highly contagious disease that affects poultry birds at any age. It is caused by a poxvirus transmitted by mostly mosquitoes and other blood-sucking insects. The reason why fowl pox is prevalent during the wet season is that mosquitoes, being the vector, breed well in this season due to the abundance of stagnant water.
Signs of Fowl Pox
- The disease affects the skin, respiratory tract and upper alimentary tract, leading to the formation of wounds which later develop into thick scabs.
- Loss of appetite
- Weakness and emaciation of the body
- Difficulty in breathing and swallowing
- Stringy discharge from the nostrils
- Pox lesions on comb, wattles and legs
- Swollen eyelids
- Soiled feathers
Treatment, Prevention and Control
Fowl pox cannot be treated but the infected birds can be given antibiotics and water. The mash or feed can be mixed with water to make swallowing quite comfortable.
- Healthy birds must be vaccinated around their 9th week of age to provide them lifetime immunity.
- Isolate or cull infected birds from the flock. Also, Get rid of stagnant water or bush around the farm to control the vectors like mosquitoes.
Read more information about fowl pox
3. Fowl Cholera
Fowl Cholera is a bacterial disease that affects birds of age 6 weeks old and above. The bacterium responsible for this is Pasteurella multocida. It is highly contagious and mortality in acute cases is high.
Signs of Fowl Cholera
In acute cases, birds that appear healthy die suddenly while in chronic cases the affected birds show the following:
- Yellow, green or grey diarrhoea
- Loss of appetite
- Laboured breathing
- Drooped wings and tail feathers
- Ruffled feathers
- Swelling of the leg joints, sinuses, wattle and foot pad
- Twisting of the neck (torticolis)
- Discharge from the nostril or beak
Note: The above signs are also similar to those of fowl typhoid.
Treatment, Prevention and Control
Fowl cholera can be treated using sulfa drugs, tetracycline and erythromycin. Poultry birds can be vaccinated against Fowl cholera by administering a fowl cholera vaccine. Maintain proper hygiene and sanitation. Practice a high level of biosecurity and prevent rodents, wild birds and other animals.
4. Salmonellosis, Escherichia coli, Pullorum Disease (Bacillary White Diarrhoea)
These bacterial diseases affect birds of all ages. They are endemic in farms or pens with poor sanitation. They affect the digestive system of the infected birds.
Signs of Salmonellosis, Escherichia coli, Pullorum
- Severe diarrhoea
- Loss of appetite
- Depression and emaciation
- Chicks suffer omphalitis
- White pasty diarrhoea in pullorum disease
- Huddle together and laboured breathing
Treatment, Prevention and Control
Salmonellosis, E. coli and Pullorum diseases can be treated by administering a broad-spectrum antibiotic to the infected bed and all the flock. High-level farm/pen hygiene and sanitation must be maintained. Biosecurity measures should be in place. Avoid feeding birds with contaminated feeds.
5. Aspergillosis
Aspergillosis is the general name given to diseases caused by Aspergillus. Due to the high humidity during the cold season, feeds or litter dampens, thus creating a favourable environment for fungus to grow and thrive. The birds also inhale aspergillus spores and these spores develop into lesions filling the lungs causing respiratory problems or discomforts.
Birds under intensive management systems would experience high disease spread if the stocking density is high and ventilation is inadequate or poor.
How to Manage Poultry Birds Optimally in the Cold or Rainy Season
To manage poultry such as chickens, turkeys, quails, duck and pheasants during cold or rainy periods, poultry farmers have to do the following:
- Add oil or fat to the diet of the birds or reduce the level of nutrients that are not required by the birds to generate heat. This is necessary to avoid wastage and reduce feed production costs since birds consume more feed to generate heat.
- Install electric bulbs or heaters in the pen to serve as a secondary source of heat for the birds. This would help the birds drink enough water and stay warm without getting the reserved energy used up in the process.
- Though very rare in an intensive system but rampant in a free-range system, birds drink from the stagnant water around, thus pick up eggs of parasitic organisms such as intestinal worms. That is why it is important to deworm poultry birds bi-monthly with effective dewormers such as piperazine. A broad-spectrum antibiotic like oxytetracycline should be administered to the birds every month.
- Construct a generous roof overhang over the entrance and sides of pens to prevent rainwater from getting into the pen whenever it rains. Construct a foot dip at the entrances of the pens and a strong disinfectant solution should be in the foot dip always.
- Vaccinate birds at the right time. See the vaccination program for layers and vaccination program for broilers and turkeys
