I have a 4 month old red sex link that was healthy a few days ago. Then about 4 days ago I noticed her limping. Checked her out and didn't see any injury and just assumed she hurt it jumping up on the saw horse. Let her sleep in the corner of the coop so she wouldn't have to jump down. She was out limping, but still getting around. Yesterday, she didn't come out of the coop. Picked her up and she wasn't using her right leg at all. Put her in the hospital in the garage and now today, she isn't using either leg and has labored breathing. What can it be??