you may want to move this to the sick and injured section to get more info
sounds like ibd
if this is an ongoing thing and chicken could be your issue as ibd is a food intolerance and some ibd dogs cannot tolerate chicken it inflames intestines and then they vomit
read this
Inflammatory Bowel Disease (IBD) in Dogs
it usually will not show up on blood work and if it does it shows up in form of high lipase, amylase, and high cpli as it mirrors pancreatitis with not all the symptoms of pancreatitis
my dog has this - so google inflammatory foods - make sure no white potato or inflammatory foods in diet. They do better on grains I believe