My little bantam hen is laying on her side looks like gasping for air

[Dimonddeanna]

Her crop feels fine to me but I am new to having chickens. To me it feels the same as it has. I had a hen pass away in November and her crop felt squishy almost and swollen and she had the brown liquid coming out. This little hen doesn't seem to be showing the same symptoms to me. She eats but with it not being the right food she must not be eating enough. She does lay eggs so I'm going to go back to the feed store and find the food you all are telling me about instead of the 5 - way the people that work there gave me. Thank you all so much, my mother is very attached to this little girl you all have been so much help

Should I go ahead and give the other hens and roosters the vitamins as well since they have been eating the 5-way also even though they are not in the condition she is