Use of Methionine Intake Restriction to Improve Egg Shell Quality by Control of Egg Weight

Abstract

The purpose of these experiments was to determine if the increase in egg weight that occurs with increasing age of hens could be reduced by the control of methionine intake to improve egg shell quality. Four methionine intakes were compared with diets in which all other nutrient intakes remained constant. Daily methionine intakes were 300, 285, 270, and 255 mg per bird. Each treatment was fed to 15 replicates of three birds each. The three-bird replicates received 300 g feed per three-hen cage per day. During Experiment 1, the diets were fed to smaller size pullets of a commercial egg strain from 38 to 62 weeks of age. In the second study, the birds were selected from the larger body size population and fed the diets from 38 to 70 weeks. This was followed by an 8-week force-molt and then continued from 78 to 102 weeks. The reduced methionine intake (255 mg in Experiment 1 and 270 and 255 mg in Experiment 2) significantly reduced the egg weight increase when compared to the 300 mg intake. The same results were obtained during the postmolt period. Egg shell quality, as measured by specific gravity, was improved in both trials when methionine intake was restricted. Shell quality of eggs produced by hens fed 255 mg daily was significantly superior to eggs produced by birds fed 300 mg. Improvement in shell quality when hens reached 50 weeks of age occurred with all treatments as compared to 300 mg. Hen-day egg production was not adversely affected.