Type D disease, more formally known as enterotoxemia, is a common and often fatal clostridial disease primarily affecting sheep and goats. It's caused by Clostridium perfringens type D and is also frequently called overeating disease or pulpy kidney disease.
Understanding Enterotoxemia (Type D Disease)
Enterotoxemia is characterized by the rapid production and absorption of toxins in the intestinal tract, leading to systemic effects and often sudden death. The "overeating" aspect stems from the fact that the conditions that often trigger the disease are associated with rapid dietary changes or excessive consumption of rich feeds, particularly grains.
Key Aspects of Type D Disease:
- Cause: Clostridium perfringens type D bacteria, which normally reside in the intestinal tract in low numbers.
- Trigger: Overeating of carbohydrate-rich feeds (grains, lush pasture), sudden dietary changes, or decreased intestinal motility.
- Mechanism: Under the right conditions, the bacteria proliferate rapidly and produce epsilon toxin, a potent neurotoxin.
- Affected Animals: Primarily sheep and goats, especially young, rapidly growing animals.
- Common Names: Enterotoxemia, overeating disease, pulpy kidney disease.
Symptoms and Signs:
The disease often progresses rapidly, and animals may be found dead without showing prior signs. However, observed symptoms can include:
- Sudden death
- Depression
- Loss of appetite
- Lack of coordination
- Nervous signs (convulsions, head pressing)
- Diarrhea (sometimes)
Why "Pulpy Kidney"?
The term "pulpy kidney" disease comes from a characteristic post-mortem finding in affected animals. The kidneys undergo rapid autolysis (self-digestion) after death, giving them a soft, pulpy texture.
Prevention and Control:
Prevention is crucial for managing type D disease. Strategies include:
- Vaccination: Effective vaccines are available to protect sheep and goats against Clostridium perfringens type D.
- Dietary Management: Avoid sudden dietary changes and overfeeding of concentrates, particularly in young animals. Gradual introduction to new feeds is essential.
- Good Hygiene: Maintaining clean living conditions can help reduce the risk of infection.
Treatment:
Treatment is often unsuccessful once clinical signs appear due to the rapid progression of the disease. If caught early, treatment may involve:
- Antitoxin administration
- Antibiotics (to reduce bacterial load)
- Supportive care (fluids, electrolytes)
In conclusion, type D disease, or enterotoxemia, is a serious threat to sheep and goat producers, primarily caused by overeating and resulting in the proliferation of Clostridium perfringens type D, leading to the production and absorption of lethal toxins. Vaccination and careful dietary management are the cornerstones of prevention.
