We bought 10 ducks. 2 mallards, 1 Khaki Campbell and 7 Pekins. They are about 4.5 months old. About 9 days ago we noticed one of the Pekins walking weird. We checked for injuries. Nothing. About 5 days ago we noticed she wasn’t trying to walk at all. I picked her up and put her on her feet and she fell forward and caught herself on her beak, pushed off the ground and threw herself backwards and landed on her back. She’s flopped around and righted herself but couldn’t walk. I put her in her pool and she instantly flipped sideways and went under while flopping about. I quickly retrieved her. Her crop area felt squishy like it was full of pizza dough/air/water? I took her to the feed store where a duck guy works. He said it felt like she had a blocked crop. He massaged it and gave her back. The next day she was eating and drinking like she was starving. She’s extremely emaciated at this point bc She couldn’t feed herself but we didn’t know. I brought her in the house and have been letting her swim in the bath tub 3-4x a day. She had HORRIBLE smelling dark/bright green poop diarrhea when my husband checked her booty. I tried activated charcoal in water as suggested for poisoning...her poop got solid and a lighter green with white swirls. Still foul smelling. We’ve given her corid for worms and poultry vitamins/electrolytes in her water. She swam great this morning but this afternoon was back to flipping sideways. She still can’t walk..at all. Her crop is now hardened and her neck area looks swollen. She also won’t stretch her neck out now unless im carrying her to the the bathroom (and she’s pretending to fly as I move her through the air lol). She has a healthy appetite and is eating and drinking (when I hold it near her). She’s also began to wheeze? Her quack is good. Her voice was hoarse when we first realized she was sick. I noticed today while feeding the rest of the flock (ducks and about 15 chickens) that 2 of the ducks have a small cough.