Dried plum supplementation enhanced the expression of liver antioxidant capacity, metabolism, and epigenetic-related gene markers in broiler chickens under heat stress conditions: Dried plum increased liver metabolism in broiler.

Heat stress (HS) poses a substantial challenge in the poultry sector, resulting in considerable economic losses as it negatively impacts the well-being and productivity of chickens. Dried plum (DP) is a rich source of minerals, vitamins, antioxidants, and phenolic compounds. Studies have indicated that DP offers various health advantages, including preserving the body's redox system, immune function, and calcium balance. In our previous study, DP supplementation improved overall growth performance and intestinal health metrics in heat-stressed broilers. Considering the beneficial effects of DP on health, we hypothesized that adding DP to the diet would mitigate the harmful impacts of heat stress in the liver of broiler chickens. Day-old unsexed broiler chicks (n = 72) were raised under standard conditions and randomly assigned to three treatment groups (n = 24/group): 1) Control, 2) heat stress with basal diet (HS), and 3) heat stress with supplement (DP). During the finisher stage, the DP group received feed containing 2.5% DP during treatment, while the other groups were given a standard finisher diet. After 21 d, birds in the HS and DP groups were subjected to cyclic heat stress conditions for 3 wk. The heat stress conditions involved exposing the birds to a temperature of 33-35°C for 8 h during the daytime. In contrast, the birds in the Control group were raised under normal conditions with temperatures ranging from 22-24°C. DP supplementation significantly increased (P < 0.05) heat shock factor 1 (HSF1) expression in the liver compared to the Control group. DP supplementation significantly increased (P < 0.05) thioredoxin (TXN), peroxiredoxin (PRDX), insulin-like growth factor 1 (IGF1), and methyl-CpG binding domain (MBD4) expression in the DP group compared to the HS group. Fructose-1,6-bisphosphatase 1 (FPB1) expression was significantly decreased (P < 0.05) in the DP group compared to the HS group. Solute Carrier Family 3 Member 1 (SLC3A1), DNA methyltransferase 1 (DNMT1), DNA methyltransferase 3 alpha (DNMT3A), ten-eleven translocation methylcytosine dioxygenase 2 (Tet2), ten-eleven translocation methylcytosine dioxygenase (Tet3), and thymine DNA glycosylase (TDG) expression were significantly increased (P < 0.05) in the DP group compared to the other treatment groups. In conclusion, post-hatch DP supplementation lessened the negative effects of HS on broiler chickens by upregulating genes related to heat shock, antioxidants, growth, nutrient transporters, and epigenetics in the liver.