Have no nucleus

Small

Come from bone marrow

Clot function

Cat platelets clump

8 - 10 per field 

Blood clotting/stopping

Mechanical phase

Chemical pahse

Series of enzymatic reactions

Coagulation cascade 

Formation of fibrin = clot

Intrinsic

Extrinsic

Common

Factors present in bloodstrem

Activated without tissue contact

Factors IV, VIII, IX, XI, XII

Activated by contact with cells and tissue fluid outside the vessel

Factors III, IV, VII 

Both intrinsic and extrinsic come together in the last phase of the cascade

Factors I, II, IV, V, X, XIII

Prevents clot formation 

EDTA - purple

Oxalates - dark grey

Sodium citrate - light blue 

Heperin - green

Sodium fluoride - grey

Decrease in platelets 

Most common platelet disease caused by:

• Excessive consumption/distruction or
• Decreased production 

Increase in platelets

Trama

Rat posion

Common

Inhibits vitamin K function

Bleeding throughout the body

Stops clotting factors initiates conssesive platelet comsumption 

Significant thrombocytopenia

Cancer

Heat stroke

Decreased or deficient production of von willebrands factor 

Most common inherited coag disorder

Rabbits/swin/dobermans

Factor VIII

Platelet counts

Activvated clotting time

Whole blood clotting time - 2 - 10 minutes

Buccal mucosa bledding time - <4 minutes

APTT/PT

Extrinsic clotting factors

Canine - 7 - 10 seconds

Intrinsic clotting factors

150 - 300 seconds 

Anticoagulant rodenticides

Bromethalin - neurotoxin

Cholecalciferol - creates calcium in blood strem

Warfin - inhibits vitamin K

Super warfin - small doses kill