Assessment of Lippia origanoides Essential Oils in a Salmonella typhimurium, Eimeria maxima, and Clostridium perfringens Challenge Model to Induce Necrotic Enteritis in Broiler Chickens

SIMPLE SUMMARY: In recent years, a considerable expansion in the use of essential oils as feed additives in animal nutrition has occurred, mainly as an alternative to antibiotic growth promoters worldwide. The objective of the present research was to evaluate dietary supplementation of essential oils from Lippia origanoides (LEO) on the in vitro proliferation of Clostridium perfringens (CP), as well as the performance, intestinal integrity, and necrotic enteritis lesions using a previously established necrotic enteritis challenge model in broiler chickens. The supernatant from digested feed supplemented with LEO and inoculated with CP reduced CP in vitro compared with the positive control. LEO showed a significant reduction of the harmful effects of induced infection/dysbiosis and a significant reduction in NE lesion scores, morbidity and mortality compared with the positive challenge control group These results suggest that the dietary inclusion of L. origanoides could mitigate some of the complex negative impacts caused by necrotic enteritis. ABSTRACT: The objective of the present research was to evaluate dietary supplementation of essential oils from Lippia origanoides (LEO) on necrotic enteritis (NE). Chickens were randomly assigned to three groups. Group 1: negative control; Group 2: positive control challenged with Salmonella typhimurium (day 1), Eimeria maxima (day 18), and C. perfringens (CP, days 22-23); Group 3: dietary supplementation LEO and challenged. On d 25 of age, serum samples were collected to evaluate fluorescein isothiocyanate-dextran (FITC-d), superoxide dismutase (SOD), gamma interferon (IFN-γ), Immunoglobulin A (IgA). Group 3 showed a significant reduction of the harmful effects of induced infection/dysbiosis and a significant reduction in NE lesion scores, morbidity and mortality compared with the positive challenge control group (p < 0.05) compared with Group 2. Digested feed supernatant, supplemented with LEO and inoculated with CP, reduced CP burden (p < 0.05). Group 3 also exhibited a significant reduction in FITC-d, IFN-γ and IgA compared with Group 2. However, a significant increase SOD was observed in Group 3 compared with both control groups. Further investigation to compare the effect of LEO and the standard treatment of clostridial NE is required.