Abstract
This review highlights some literature data on salicylic acid supplementation and its effects on heat-stressed broiler chickens. The current review will assess the potential use of supplemented salicylic acid and highlight its mode of action to decrease the adverse effects of heat stress on broiler production, including growth performance, animal health, gut microbiota, and heat-shock protein expression in broiler chickens. Dry matter intake, growth rate, and feed conversion ratio were improved for broilers when salicylic acid was added to their diet either in powder form or supplemented in their drinking water. It also improves carcass quality in both broiler chicken and Japanese quail. Data from recent literature showed lower blood cholesterol (up to -26.3%) and triglycerides (up to -30.7%) and glucose (up to -16.4%) were found in heat-stressed chickens fed 50 – 100g/100 kg of salicylic acid compared to chickens fed a regular diet. In addition, salicylic acid improves the oxidative status of birds by lowering the amount of malondialdehyde in the liver under HS. Salicylic acid supplementation also inhibits colonization of harmful microbiota and intestinal pathogens, such as Salmonella, Clostridium perfringens, Enterococcus species, and E. coli, in the gut of broilers by enhancing intestinal barrier function and maintaining intestinal microflora balance. Moreover, the review highlights the value of salicylic acid as a natural alternative supplement for its anti-inflammatory and antioxidant abilities in animal nutrition to mitigate the negative effects of heat stress and enhance poultry production.

Key words: Animal health; Broiler chickens; Growth performance; Heat stress; Salicylic acid.