Performance, carcass quality, serum biochemistry, and stress resilience in broilers supplemented with chromium picolinate and lemon peel powder during hot-humid summer.

Heat stress negatively affects broiler growth, productivity, and mineral retention, particularly chromium, leading to impaired metabolism and reduced growth rate. Chromium supplementation helps alleviate stress and improves weight gain in heat-stressed birds. Citrus peel, rich in bioactive compounds, can also enhance growth performance and feed efficiency in broilers. A total of 288, day-old CARIBRO VISHAL broiler chicks were reared in 9 different treatment groups with 4 replicates per treatment and 8 birds per replicate in cages. Treatment groups were fed with different levels of Chromium Picolinate (CrPic) and Lemon Peel Powder (LPP). Groups were: T1 (Basal Diet, BD), T2 (BD + 0.5 mg CrPic), T3 (BD + 1 mg CrPic), T4 (BD + 2 g LPP), T5 (BD + 2 g LPP + 0.5 mg CrPic), T6 (BD + 2 g LPP + 1 mg CrPic), T7 (BD + 4 g LPP), T8 (BD + 4 g LPP + 0.5 mg CrPic), and T9 (BD + 4 g LPP + 1 mg CrPic). The results demonstrated that the combined supplementation of CrPic and LPP (T5) significantly (P < 0.05) enhanced body weight, although feed conversion ratio (FCR) remained unaffected. On serum assay, there was no notable interaction effect (P > 0.05) on serum protein, albumin, globulin, cholesterol, and triglyceride levels. However, chromium picolinate supplementation alone significantly (P < 0.01) reduced serum cholesterol and triglyceride concentrations. Notably, an increasing dietary inclusion of CrPic and LPP significantly (P < 0.01) lowered the Heterophil-to-Lymphocyte (H:L) ratio, indicating a potential stress-mitigating effect. Additionally, corticosterone levels were significantly (P < 0.01) reduced with supplementation highlighting its potential benefits in mitigating heat stress in broilers during summer.