The most important diagnostic steps for the veterinary surgeon is a thorough clinical examination of the bird. This together with complete history of the bird and its flock is vitally important to be able to make diagnostic and therapeutic plans. It is crucial for the veterinary clinician to be familiar with the normal parameters for the species and breed being seen as especially in chickens there are wide variations even between breeds.
When appropriate there are a range of diagnostic procedures that help with obtaining a diagnosis on a case by case basis
Haematology and biochemistry
Plus a range of specialist tests pertaining to various areas of the body.