I have a 10 month old White Leghorn hybrid hen named "Kinako" She started laying at around 8 weeks of age and laid an egg almost everyday, non stop for about 5 months. Then she got sick and started laying shelless eggs. I took her a poultry vet, he checked her over and said she wasn't egg bound, crop wasn't impacted and had no intestinal worms. He suggested she may be deficient in Calcium and may have an infection, possibly in the oviduct. He prescribed 10 x 25mg Antirobe (clindamycin hydrochloride) capsules to be taken 1 each day + a calcium and vitamin D3 liquid to be given twice a day. I also gave her a bowl of shell grit to eat to help boost her calcium intake. She gradually improved, but stopped laying completely. About 1 month later she laid an odd shaped egg (long and slender) and contained no yoke. She then stated laying membrane only eggs with no shell every few days. She seems lethargic and just sits every few days then improves and gets lethargic again a few days later. When lethargic she doesn't want to eat, but appetite improves when she gets better. Recently she has been laying eggs with no shell or membrane, just a white mess in her nesting box or on the ground. I have been adding apple cider vinegar to her drinking water and giving her a warm bath when she gets lethargic (just in case she has an impacted egg) Has anyone got any suggestions as to what might be wrong with her ?