Infectious Diseases:
* Bacterial Infections: These can cause a range of illnesses from pneumonia and mastitis to footrot and enterotoxaemia.
* Viral Infections: Examples include bluetongue, sheep pox, and foot-and-mouth disease.
* Parasitic Infections: Internal parasites like roundworms, tapeworms, and lungworms can cause significant health problems. External parasites like lice, mites, and keds can lead to skin irritation and infections.
* Fungal Infections: Ringworm and other fungal infections can affect the skin and hooves.
Nutritional Deficiencies:
* Lack of essential nutrients: Deficiencies in vitamins, minerals, and other essential nutrients can lead to various health issues, including anemia, bone disorders, and reproductive problems.
* Overgrazing: Excessive grazing can deplete pastures of essential nutrients, making sheep vulnerable to deficiencies.
Environmental Factors:
* Extreme weather: Hot, cold, or wet weather can stress sheep and make them more susceptible to disease.
* Poor housing conditions: Overcrowding, lack of ventilation, and poor hygiene can contribute to the spread of infectious diseases.
Genetic Factors:
* Congenital defects: Some sheep breeds are prone to certain genetic conditions that can weaken their immune system or make them more susceptible to specific diseases.
Management Practices:
* Poor sanitation: Inadequate sanitation practices can contribute to the spread of infectious diseases.
* Stressful handling: Rough handling, overcrowding, and sudden changes in environment can stress sheep and weaken their immune system.
* Vaccination failures: Incomplete or improper vaccination can leave sheep vulnerable to preventable diseases.
Other Factors:
* Trauma: Injuries from predators, accidents, or fighting can make sheep susceptible to infections.
* Toxicity: Ingestion of poisonous plants or chemicals can cause illness or even death.
Understanding the specific cause of illness in sheep is crucial for proper diagnosis and treatment. This requires careful observation, veterinary examination, and potentially lab testing.