Study on Determining Appropriate Protein Levels in the Diet of Naked Neck Chickens in Nghe An

This study aimed to determine the appropriate dietary protein levels for commercial Naked Neck chickens in Nghe An province, Vietnam. A total of 450 one-day-old chicks were randomly assigned to three treatments with different crude protein levels: 17%, 18%, and 19% (0–8 weeks), and 15%, 16%, and 17% (9–16 weeks), while metabolizable energy was kept constant at 3000 Kcal/kg. Growth performance, survival rate, and body weight were evaluated over 16 weeks. The results showed that protein levels did not significantly affect survival, which remained high (93.33–94.67%). However, body weight was strongly influenced by dietary protein content. Chickens fed with higher protein diets (19% for 0–8 weeks and 17% for 9–16 weeks) consistently achieved the highest body weights at all stages, while those on the lowest protein diets (17% and 15%) had the lowest weights. These findings suggest that a dietary protein level of 19% in the starter phase and 17% in the grower phase is most suitable for optimizing growth performance in commercial Naked Neck chickens, without compromising survival.