General Veterinary Pathology

DEFINITION AND CLASSIFICATION

Definition

• Aetiology is defined as study of causation of disease.

Classification

There are several agents or factors that can produce disease in animals and which originate from within the body or outside the body. Thus, the causes are broadly classified into two categories.

• Predisposing causes (Intrinsic factors)
• Definitive causes (Extrinsic factors)
• Predisposing causes make the animal susceptible to definitive causes. These include
• Heredity-Inherited-Glycogen storage diseases e.g. Pompe’s disease (Lysosmal acid maltase deficiency) in cattle, dog
• Species-Rinderpest is found in cattle not in other animals.
• Breed-Certain breeds are more susceptible to some diseases than others. Heavier breeds of dogs suffer from bone diseases
• Age-Young animals are comparatively more prone for disease than adults.
• Sex-Diseases of reproductive organs in respective sex.

Colour (Pigmentation)-Sunburns in melanin deficiency, eye cancer in Hereford cattle