Secondly, birds must be monitored for obesity. The only way to do this is to catch up birds, weigh them and examine them for fat deposits under the skin on their sides. Recording and monitoring weights over time will eliminate obese birds. Birds that are always obese, even when on proper diets, should not be bred. This will pass on to the offspring the genetic tendency toward obesity.
Obese hens are also more prone to become egg bound when breeding.
Adequate exercise is important for all birds, but obese birds must be exercised cautiously at first. Any significant increase in exercise could kill them. I have seen many birds that were reported by the owner to have died of a heart attack when flying, only to find out at necropsy that the real problem was obesity. Birds should be given large flight cages when not breeding to stimulate exercise. Obesity is a common problem in cockatiels.