Effects of dietary metabolizable energy levels and beak trimming on the performance, egg quality, and economic viability of layers.

Considering the market availability of new commercial layer strains with distinct characteristics and behaviors, studies to update their nutritional requirements and to evaluate the need to adopt management practices, such as beak trimming, are needed. The objective of the present study was to evaluate the effects of dietary metabolizable energy (ME) levels and beak trimming on the live performance, egg quality, and economics of commercial layers. A total of 640 Novogen White layers were distributed according to a randomized experimental design in a 5 × 2 factorial arrangement (5 ME levels × 2 beak trimming treatments), totaling 10 treatments with 8 replicates of 8 hens each. The evaluated dietary ME levels were 2,600; 2,700; 2,800; 2,900; and 3,000kcal/kg of feed. Layers were beak-trimmed once (7 days old) or twice (7 and 70 days old). Live performance and egg quality mesuraments and production economics were analyzed. Egg production was positively influenced by dietary ME levels. Feed intake (FI), feed conversion ratio (FCR), egg weight, albumen height, Haugh units, and eggshell strength were positively influenced by increasing dietary ME levels. Hens beak-trimmed once presented higher feed intake and worse FCR than those beak-trimmed twice. Beak trimming did not affect egg production, egg weight, albumen height, Haugh units, and eggshell strength. Production costs increased as dietary ME levels increased. Higher production cost was determined for hens beak-trimmed once than for those beak-trimmed twice. Total revenue was not influenced by the treatments. Gross margin was linearly decreased as dietary ME levels increased and was lower when hens were beak-trimmed once. Increasing dietary ME levels and beak trimming hens once reduce the economic viability of egg production.