Effects of curcumin on jejunal morphology and intestinal integrity of broiler under heat stress

Heat stress adversely affects poultry production, intestinal health, and antioxidant levels. This study investigated the effects of curcumin supplementation on the jejunal morphology of broilers under heat stress. A total of 108 one-day-old male Arbor Acres broilers were divided into three groups: the control group (C), the heat stress group (HS), and the curcumin group (CUR). The C and HS groups were fed a basal diet, while the CUR group received 50 mg/kg of curcumin, supplemented from days 8–42. From days 21–42, the HS and CUR groups were exposed to 34 ± 1 °C for 8 h daily (9:00–17:00), with the remaining time spent at 22 ± 1 °C. The C group was maintained at 22 ± 1 °C throughout the experiment. The results revealed that curcumin supplementation alleviated jejunal mucosal damage. under heat stress. It increased the villus height to crypt depth ratio (V/C ratio) and significantly upregulated the expression of TJP1, ZO-1, MLCK, and BCL-2. Additionally, curcumin downregulated the expression of CASP3 and CASP9 in the jejunum. Furthermore, curcumin activated autophagy by enhancing the expression of SIRT1, PGC-1α, and Beclin1. In summary, curcumin supplementation can help maintain gut health in broilers under heat stress and exert protective effects at the cellular level.