My six month old Cochin bantam rooster won't eat very much and has lost some weight. He looks great and healthy. Beautiful red comb and wattles. Won't leave the hens alone and crows his head off. Shows no signs of any illness except a bit of weight loss from not eating. He's been doing this for a bout a week. Only eats human corn, lettuce, a bit of grass and nuts, won't hardly touch any regular chicken feed. Any suggestions?