The Effects of Dietary Supplementation of Encapsulated Thyme Essential Oil on Growth, Pro-Inflammatory Cytokines, and Serum Amino Acid Profiles of Broiler Chicks Challenged with Salmonella Typhimurium

Salmonella Typhimurium (S. Typhimurium) causes inflammation and has adverse effects on the growth of broiler chicks. Meanwhile, plant derivations improve the growth performance and decrease inflammation, but they do not have enough stability. Encapsulation of essential oils is a new strategy for decreasing their instability. This study was conducted to investigate the effects of dietary supplementation of encapsulated thyme essential oil (ETEO) on growth, inflammatory cytokines, and amino acid profiles of broiler chicks challenged with S. Typhimurium. Three hundred one-d-old broiler chicks were assigned into 6 groups, and 5 replications per group. The broiler chicks (3 groups) were challenged with S. Typhimurium on day 21 and birds received basal diet (positive control), encapsulated thyme (P-ETEO), and non-capsulated thyme (P-NETEO), while other groups received the same diets, but under normal as a negative control, encapsulated thyme (N-ETEO) and non-capsulated thyme (N-NETEO). Growth performance, pro-inflammatory cytokines, and serum amino acid profiles were assessed on day 42. The challenged birds in positive control showed lower growth performance, higher concentration for inflammatory cytokines, and disturbed blood serum concentrations for amino acid profiles compared to the negative control (PS. Typhimurium had negative effects on growth, immunity, and inflammation, but dietary inclusion of the ETEO could decrease its negative effects.