Pigeons are noted for their unique ability to ! produce 'pigeon's milk', a soft, cheesy and nourishing secretion, especially during the breeding season. It is i formed by the degeneration of the epithelial cells lining the crop. It is regurgitated into the mouth of the young j birds until they are old enough to manage a grain-diet ; like their parents. The pigeon's milk includes water, fat, I protein (casein) and lactose. The milk is produced by both sexes and contains 35 per cent of fat.