My hen has gained weight recently, though it seems like it's only her backside. She is super skinny up front and has nothing in her crop but it seems really fat on the opposite side. She doesn't seem to be egg bound. Her comb is bright red and she doesnt show signs of straining. However she has been less active and unwilling to jump and she likes to lay down more. There is also a weird tapping noise that could possibly be her heartbeat. It seems to be coming from that area. The tapping is emitting in patterns of 1-3 randomly. Anyone have a clue what could be wrong?