this study evaluated chitosan nanoparticles (ChNPs) as a feed additive for broilers. A total of 400 d-old male Ross 308 broilers were randomly allocated into four treatments with five replication pens, each pen had 20 broilers. The experimental diets were as follows: First group was fed a basal diet only (control); 2nd, 3rd, and 4th groups received a basal diet supplemented with 50 (ChNPs-50), 100 (ChNPs-100), and 150 (ChNPs-150) mg ChNPs /kg of feed, respectively. Results showed that dietary supplementation with ChNPs reduced mortality and feed conversion ratio, while weight gain and feed intake showed non-significant trends toward improvement. Abdominal fat decreased significantly, whereas breast weight increased, with the highest values in the 100 and 150 mg/kg groups. Dressing percentage improved significantly, while liver weight remained unaffected. Linear trends confirmed dose-dependent improvements in abdominal fat, breast yield, and dressing percentage. Regarding liver function, ChNPs significantly reduced alanine aminotransferase activity. In renal function, creatinine decreased significantly in the highest ChNPs group, while uric acid and urea showed non-significant declines. ChNPs markedly improved lipid profiles. Low-density lipoprotein and total cholesterol decreased significantly, while high-density lipoprotein increased in the 150 mg/kg group. Triglycerides also declined significantly at the highest supplementation. Linear effects for all lipid parameters indicated dose-dependent improvements. Heterophils decreased and lymphocytes increased in ChNPs-supplemented birds, resulting in a significantly lower HET/LYM ratio. Overall, dietary ChNPs supplementation enhanced growth performance, carcass quality, liver and kidney function, lipid metabolism, and immune cell distribution in broilers, with dose-dependent effects evident across multiple physiological and biochemical parameters.
