Hypothesis 2 :		INFECTIOUS


	This foal could possibly have a bacterial/viral infection obtained through the 
umbilical cord.  This could have localized in the fetlock joint.  An infection leads to an 
inflammatory response causing heat and pain.  The infection leads to chemotaxis  and the 
filtrate of inflammatory cells leads to edema.  Because the mare is currently vaccinated 
and the foal received colostrum, it is unlikely that the foal inherited an infection from the 
mare.  The foal is more susceptible to infection due to the young age and the lack of time 
to build sufficient immunity.  A simple injury, trauma, or umbilical infection could have 
potentially devastating effect.