1 1/2 yo RIR w/large squishy crop, dark green droppings, cold feet/comb/wattles, etc...
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Crops can become sluggish and slow to empty during illness. If the crop becomes very large, they can sometimes vomit with crop massage. Crop problems can be very hard to deal with, but she just may have a crop that isn't working properly due to what is wrong with her. Sorry that I can't help more.
Actually I was just reading another post today saying that most E.coli infections which are common with EYP, are resistant to tetracyclines. Enrofloxacin or Baytril, or penicillin drugs may be better. If you do a search at the top of the page for "baytril sources," you can buy it online. If you can get her seen by a local vet, it might be easier, and you might get a more accurate diagnosis.