My two RIR chicks, about 2 weeks old, seem healthy in every way. They are active, look great, eating well and drinking well. I noticed the other day that one has very loose stools.. squirty.. they even sound squirty when she goes. The are on medicated starter and were also on Arythro (sp?) for a week when one of their mates came down with an illness (and survived).. I add vitamins and electrolytes to their water and started adding powdered probiotics yesterday.. Is this just the result of the meds or something I should worry about?