I've noticed that my hen, Rosemary, has lost weight over the last several months. She only weights 4.5 pounds when the Dominique standard for hens says they should weigh around 5-6 pounds. One of our pullets from the chicks that she hatched in April, Tansy, is already much bigger and truer to standard size than Rosemary. Additionally, her legs are very pale. She is acting like her normal self, eating good and foraging, laying regularly, and her comb is nice and bright red still. Any idea what could be causing this? Should I worm her or treat her for something specifically? She is a year and a half old. Thank you!!