Essential Oils in Broiler Chicken Production, Immunity and Meat Quality: Review of Thymus vulgaris, Origanum vulgare, and Rosmarinus officinalis

Abstract

The use of essential oils in animal nutrition has attracted attention as a potential substitute for antibiotic growth promoters in the past twenty-five years. This paper will review the current scientific evidence on the usage of essential oils from Lamiaceae family members such as Thymus vulgaris (thyme), Origanum vulgare (oregano), and Rosmarinus officinalis (rosemary) in broiler nutrition in terms of production results, immunity, and meat quality properties. Essential oils are effective in broiler nutrition when incorporated into the diet on a variety of levels, such as dietary composition, level of feed inclusion, and bird genetics. Moreover, the efficacy of essential oils is influenced by many factors, such as the composition of the oil. Due to big differences in the composition and sources of essential oils, comparing different studies using them can be challenging. Therefore, biological effects may differ significantly. Despite this, a great deal of research supports essential oils’ potential use as natural, antibiotic-free growth promoters for broilers. Growth promotion mechanisms are still not clearly understood as there is limited information on essential oils’ effect on nutrient digestibility, gut function, and the immune system. There is no question that essential oil consumption can reduce pathogen growth in the gut, but their effects on the intricate gut ecosystem as yet remain unclear. This review concludes with further recommendations regarding the application of dietary essential oils in broiler nutrition.