Lethargic hen, lays down a lot; heat or something else?

[chicken-ing]

This is my first post here, so apologies if I'm doing anything incorrectly.

One of my hens (an ISA brown) that is usually very peppy and eager to scratch and eat has recently become lethargic and slow to move. She'll run to me and will eat treats if given, but besides that I have barely seen her eat or drink, unlike the rest of the flock. She just looks sad. It's important to note we're in the mid-atlantic where the heat index has frequently topped 90 F, yet while the other hens are acting normally despite panting in the obvious heat, she just lays down a lot and does nothing, and she hasn't shown any signs of heat exhaustion or stress. It's very unlike her. I've yet to see her poop. Crop has been very small.
She also had an impacted crop several months ago and was treated with surgery and fully recovered, though she was malnourished for a few weeks following it.

Thank you in advance for any help

 

[Eggcessive]

How old is she? Has she shown any signs of molting? My hens will act aloof and eat little during a molt. It would be good to look her over for mites and lice. Does she normally lay eggs? Is she gasping or having labored breathing?Heat does take it’s toll on chickens and they may lie around a lot. I would try some Poultry NutriDrench for a couple of days 2 ml daily.

 

[chicken-ing]

How old is she? Has she shown any signs of molting? My hens will act aloof and eat little during a molt. It would be good to look her over for mites and lice. Does she normally lay eggs? Is she gasping or having labored breathing?Heat does take it’s toll on chickens and they may lie around a lot. I would try some Poultry NutriDrench for a couple of days 2 ml daily.

She's around 2 years old. No signs of molt, though two other girls are. No problems or difficulty breathing either, haven't seen her pant or gasp at all. She normally lays eggs yes, but stopped for several months when suffering from sour/impacted crop. She recently started regularly laying again actually but stopped when the temperatures rose.
I'll check for mites and lice tomorrow.