I have a 16 week old barred rock pullet (I have 3 other pullets this age (1 is a barred rock), came from the same breeder, all 3 are the same size & seem to be fine) that only wants to lay around. She eats/drinks but doesn't get excited when fresh food/water is brought or when I come w/ special treats. She has been acting like she is "drunk" & seems to be walking like a duck. I checked her for any signs of pain (nothing), checked for bugs (found 2 lice, which we treated), her comb is pale along w/ her wattles. I dusted the coop/nest boxes w/ DE & also dusted my flock as well on Monday evening. Tonight I brought her in & gave her some yogurt w/ oatmeal & some water w/ electrolytes. PLEASE help me figure out what else I can do to help her.