Help unwell chicken

Hi hope someone can help!! i have 3 hybrid girls all at two and a half years old, been fantastic layers in that time but since Christmas no eggs at all!! thought they maybe having a moult but not many feathers have come out, maybe just having a rest but 7months later still no eggs!
now one of them has a really runny bum, flat comb and not looking to good. still eating just about and drinking a lot, looks like she just wants to sleep. have wormed them, given apple cider and verm-x. last month we gave them a bath (which they loved) and red mited the shed.
have looked at the poo samples on the site and it looks like the one associated with overheating, it has been very warm over the last couple of days, think it could it be that but worried about the other symptoms!!!
Please help someone

just been reading the site could she be egg bound?? if so what should i do??

No advice, I'm afraid.  I just wanted to welcome you to the forum and wish you luck with your girls 

On this forum many people find that VermX can prevent in some cases but does not kill worms effectively if they are present.  The usual recommendation is to use Flubenvet wormer.

On this forum many people find that VermX can prevent in some cases but does not kill worms effectively if they are present.  The usual recommendation is to use Flubenvet wormer.

ok thanks for the tip,  i'll get some in the morning and try it out

that was why I asked - Verm-x is purely a herbal preventative that has no proof of actually working, in fact many have found that it doesn't by which time their birds have a very high worm infestation.
Start tomorrow and give them all a weeks course. Make sure you follow the instructions properly and stop all other treats.

ok so have given flubenvet to my girls, washed out the run and given poorly chicken (Ashley) a wash and some tlc. whilst washing had a poke around and she seems really squishy under her vent, it seems swollen but she makes no fuss when i touch it. also i noticed she has lost weight since the last bath about a month ago! she still has poo like a water jet, haven't seen her eat today but she is scatching around. it's so frustrating not knowing whats wrong!!
more help please