Anaemia

Anaemia is defined as decreased oxygen carrying capacity of blood.

Anaemia devolops due to 

Blood loss.
Increased RBC destruction.
Decreased RBC production.

Clinical signs

Pale mucous membrane
Reduced exercise tolerance.
Depression
Inappetance
Muscular Weakness
Tachycardia
Tachypnea
Fever, icterus in severe haemolysis

Treatment

Identification and elimination of cause.
Provision of nursing care.
Haematinic therapy can be given .
Iron,copper and cobalt mixture can be given orally.
Minimize the stress

References
The Equine Manual by Andrew J.Higgins and Jack R.Snyder