I have a 3 day old Speckled Sussex chick that looks like it is gasping for air. It moves its head up in a jerky type motion and opens its beak for each breath. It is standing with its eyes closed. This started yesterday, mid-day and is still the same. She has had a Mareks Vaccine, is on Purina Start and Grow (med), plain water, brooder temps are fine, brooder lined with paper towels. When she opens her eyes, they are clear with no cloudiness or crusty's. She has not had treats but could have gotten one (moths are attracted to the brooder light). There is also nothing oozing from her nose or lodged in her throat. There is a little pasty poo around the vent, but no blockage- she has poo'd 2-3 times since being separated at 4:30 this a.m. She chirps, but not super loud or excessively. I have seen her drink once since being separated and have not seen her eat. I have not given any of the chicks any type of vitamins/electrolytes, yogurt, ACV, etc. yet. I am stumped. All the rest (34 chicks) are fine. Can anyone help? The feed store closes in 30 mins- so I have to hurry if I need to go pick up any meds.