Sudden Death Syndrome in Broilers is also known as Acute Death Syndrome
Dr. Abdul Jabbar Kazim Al-Kanani / Consultant Veterinarian Specialist / Al-Noor Veterinary Laboratory \ Basra
This condition is also known as coup, or Acute Disease Syndrome (ADS), or death in good condition, or heart attack or pulmonary edema. It is associated with fast-growing broiler birds.
There are no clear clinical signs of the Sudden Death Syndrome (SDS), until a minute before death. Sudden death syndrome is a condition mainly associated with commercial broiler feeding systems, where healthy birds die suddenly for no apparent reason and there is no unusual behavior until less than a minute before death. Then there may be sudden screaming, loss of balance, convulsions, and frantic wing flapping. Birds tend to die on their backs (hence the term ‘rolling over’), with one or both legs raised.
Post-mortem birds show a pale, enlarged liver, the kidneys may be pale and the lungs congested and swollen, although the latter may be an artifact of post-mortem. It has been shown that in medium to fast-growing breeds, high-quality chicks tend to have increased incidence of rolling over and legs-up at 5-6 weeks of age.
Causative factors:
- Management: Management factors that cause stress, such as high light intensity, high temperature or high humidity. High density per square meter with little movement of birds may induce or contribute to this condition. Bright sunlight may be a contributing factor, apart from providing shade.
- Nutritional: including feeding methods, as feeding of pelleted feeds can lead to high growth rates and an increased risk of SDS due to the high oxygen demand for muscle growth, causing myocardial hypertrophy and sometimes cardiac rupture. Diets that contain a high percentage of sugars as a source of energy instead of high starch help to develop the syndrome.
Immediate treatment by following the following:
- Increase ventilation by using fans that move air over the birds. A puller placed on an iron frame at a height of only one meter from the ground and in more than one place inside the hall (floor breeding).
- Give daily doses of electrolytes containing potassium salts (potassium chloride and potassium citrate) in water cooled with ice to reduce heat stress.
- Make feeding at night and increase the turning off periods every two hours of lighting for one hour of turning off to rest the birds and reduce movement.
- Speed up the marketing of high-weight chickens to reduce the density of breeding.
- Use ice with drinking water and also in the afternoon spray cold water directly on the chickens.
Prevention strategies:
- Pay great attention to the thermal insulation of the ceilings of the halls and do not rely only on metal layers containing the insulating material (sandwich panel). It is possible to put palm fronds or cardboard on the roof from above to reduce the effect of the falling sun heat or organize a water sprinkler for the roof during peak heat hours.
- Use diets that reduce the density of nutrients by 5-7% (putting bran with the feed) on very hot days.
- Reduce the movement of workers inside the halls during the afternoon.
- Cooling should be at its most efficient. In Iraq, we suffer from this condition, especially in the southern regions of the country and during the summer days when the humidity is high, exceeding 85% (days of eastern weather), where we notice panting and crowding of chickens and the appearance of sudden death in flocks prepared for marketing and with high weights, and we notice chickens walking in the hall rising up and turning over on their backs and dying.
- It is possible that it appears in flocks that have suffered from diarrhea as a result of kidney failure due to infection with infectious bronchitis. Renal strain (Renal Strain) and acid imbalance in body fluids (Acidosis).
