I would take some sample of poo to the closest vet that can do a fecal float. Then they can tell you if there is a worm problem, and if so, which wormer to use to be most effective. Oyster shell is for calcium only, not the same as grit (it dissolves), but they will not eat it unless they need it, if it is separate from their food. I would also cut out the scratch and bread completely, and make their treats highly nutritional ones such as plain yogurt, washed cottage cheese, small amounts of cat food or shredded cheese, mealworms, etc...until you get them back to normal weight. Could you also take one of the dead or dying birds in for a necropsy? to find out what is going on for sure.
Last edited: