I would agree with @KikisGirls. My flock are just going through a heavy moult and during the early stages of it, they went right off their food and lost a massive amount of weight... not just feathers. I have not wormed them, but they have now started eating heartily again and piling the weight back on as well as growing new feathers. I have not witnessed such a drastic weight loss in previous years when they were free range, but this year being penned, it was very dramatic..... I think it may be that when they free ranged they found plenty of worms etc to boost their diet. I even tried changing from layer to grower but they were equally uninterested.
I'm another one for having a worm egg count done on a faecal sample rather than give them chemicals they may not need.
I'm another one for having a worm egg count done on a faecal sample rather than give them chemicals they may not need.