I'd like to suggest that you post your question in the 'Sick & Injured' section. You will most likely get more answers to your question. Can't believe that all the tests that were run didn't show anything.

I am so sorry. ~Joanne~
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Joanne

Eli

Chipper

Eva

Snowboy

Rosie(R.I.P. 1996-July 29, 2013)

Cocoa(R.I.P 1998-April 26, 2012):