Dietary oregano aqueous extract improves growth performance and intestinal health of broilers through modulating gut microbial compositions

Background Intestinal health plays a pivotal role in broiler chicken growth.Oregano aqueous extract(OAE)effec-tively exerts anti-inflammatory and antibacterial effects.However,the protective effects of OAE on intestinal health in broilers and the underlying mechanism remain unclear.This study aimed to investigate the potential effects of OAE on growth performance,the gut microbiota and intestinal health.A total of 8401-d-old male and female broilers(Arbor Acres)were randomly allocated into 6 groups as follows:basal diet(Con),Con+antibiotics(Anti,colistin sulfate 7 g/kg,roxarsone 35 g/kg),Con+400,500,600 and 700 mg/kg OAE(OAE400,OAE500,OAE600 and OAE700).Subse-quently,fermentation in vitro together with oral administration trials were carried out to further assess the function of OAE on intestinal health of broilers.Results Dietary 700 mg/kg OAE supplementation resulted in an increase(P<0.05)in body weight and a decrease(P<0.05)in feed conversion ratio when compared with the control during d 22 to 42 of the trial.OAE addition resulted in lower(P<0.05)jejunal crypt depth and mRNA expression of IL-4 and IL-10 at d 42.In addition,dietary OAE addition increased the abundance of Firmicutes(P=0.087)and Lactobacillus(P<0.05)in the cecum,and increased(P<0.05)the content of acetic acid and butyric acid.In the in vitro fermentation test,OAE significantly increased(P<0.05)the abundance of Lactobacillus,decreased(P<0.05)the abundance of unspecified_Enterobacteriaceae,and increased the content of acetic acid(P<0.05).In the oral administration trial,higher(P<0.05)IL-4 expression was found in broilers when oral inoculation with oregano fermentation microorganisms at d 42.And SIgA content in the ileum was significantly increased(P=0.073)when giving OAE fermentation supernatant.Conclusions Dietary OAE addition could maintain intestinal health and improve growth performance through enhancing intestinal mucosal immunity and barrier function mediated by gut microbiota changes.

Antioxidant Action of Rosemary and Oregano Extract in Pre-Cooked Meat Hamburger

The main goal is to compare the antioxidant potential of rosemary and oregano natural extracts in precooked beef burger by assessing the lipid oxidation extent and sensory analysis. Five formulations (F) of hamburger were prepared from beef and mechanically separated as follows: meat containing sodium erythorbate (F1);deodorized rosemary extract (F2);oregano extract (F3);rosemary plus oregano extracts (F4) and without antioxidant addition, denominated control formulation (CF). The samples were frozen at ?18°C for 24 hours, then submitted to heat treatment in an electric oven with internal controlled temperature of 75°C, and again frozen for a period of 30 days. The lipid oxidation extent (determined by thiobarbituric acid reactive substances— TBRS) was evaluated at 0, 15 during 30 days. After heating in plate to temperature of 75°C, the samples were submitted to color, taste and odor evaluation by 40 untrained tasters. The formulations F1, F2 and F4 presented lower concentrations of TBRS, whereas CF at day zero already showed very high values, indicating oxidation of the product. The samples showed good acceptance in the sensorial analysis.