Production performance and egg quality of Japanese quail fed different levels of protein

Abstract:

Small-scale poultry farmers in East Asia face a persistent problem: feed accounts for 65-70% of total production costs, and protein is the most expensive component. Identifying the protein level that maximises egg output without inflating feed costs is therefore a practical priority. This research evaluated the production performance and egg quality of Japanese quail (Coturnix japonica) fed diets containing 18%, 20%, 22%, and 24% Crude Protein (CP). Two hundred and forty day-old quail chicks were randomly assigned to four dietary treatments with three replicates of 20 birds each. The feeding trial lasted from week 5 to week 16 of age at the Poultry Research Unit of Chungnam College of Food Science, Daejeon, South Korea, between May and September 2022. Birds receiving 22% CP achieved the highest hen-day egg production (79.8%), the best feed conversion ratio (2.91), and superior egg quality parameters including shell thickness (0.221 mm), Haugh unit (88.4), and yolk colour score (7.1). Increasing protein to 24% CP did not yield further improvements and slightly raised feed costs. The results indicate that 22% crude protein is the most efficient dietary level for Japanese quail during the laying phase under Korean management conditions.