1c of TC30 is 1/3 of a pound - hardly a great deal of protein
And, you might as well give a vit/min supplement instead of this amount.
Just drop the TC for a few days and see if he goes back to his normal self. If he does, then you know it’s probably a reaction to an ingredient in the TC. You can then put him on the E32 and see if the same reaction occurs. If so, my guess would be the soy. If not, then you know it’s something pretty specific to the TC30
Fat Cat is a high fat supplement, hence “weight builder”. It’s not at all a protein supplement or a truly nutritional supplement. It may be “high protein” on the label - 24% - but you feed 1-2 30gm scoops. 1lb of 454gm, so even 2 scoops is only about 1/8th of a pound. Ration balancers at 30-32% protein are fed at minimally 1lb, with highest amounts in the 3-3.5lb range.
Different companies market their “ration balancer”, or “diet balancers” differently. TC happens to call theirs a “performance supplement” because of the increased nutritional value. But lay them ALL side by side and they are all just about identical, little tweaks here and there (ie Enrich 32 is 32% protein instead of the typical 30, and contains about 12gm of lysine per pound instead of the typical 10)
Progressive calls theirs “diet balancers”.
Different labeling/marketing, same basic products