Effects of thymol and carvacrol supplementation on intestinal integrity and immune responses of broiler chickens challenged with Clostridium perfringens

Abstract

BackgroundNecrotic enteritis caused by Clostridium perfringens infection leads to serious economic losses in the global poultry production. In the present study, we investigated the protective effects of essential oils (EO, which contained 25 % thymol and 25 % carvacrol as active components) supplementation on growth performance, gut lesions, intestinal morphology, and immune responses of the broiler chickens infected with C. perfringens. A total of 448 1-day-old male broiler chicks were allocated into eight treatment groups following a 4 × 2 factorial arrangement with four dietary EO dosages (0, 60, 120, or 240 mg/kg) and two infection status (with or without C. perfringens challenge from d 14 to 20).ResultsThe challenge did not impair the growth performance of birds, but induced gut lesions and increased crypt depth in the ileum (P ≤ 0.05). It also down-regulated the claudin-1 and occludin mRNA expression (P ≤ 0.05), up-regulated the mRNA expression of interleukin-1β (P ≤ 0.05), tended to increase the toll-like receptor (TLR) 2 mRNA expression (P < 0.10) in the ileum, and enhanced the mucosal secretory IgA production (P ≤ 0.05). In the challenged birds, dietary EO supplementation linearly alleviated the gut lesions and improved the ratio of villus height to crypt depth (P ≤ 0.05), and the supplementation of 120 and 240 mg/kg EO increased the serum antibody titers against Newcastle disease virus (P ≤ 0.05). Regardless of challenge, the EO supplementation showed a tendency to linearly elevate the feed conversion efficiency between 14 and 28 d of age as well as the occludin mRNA expression (P < 0.10), and linearly inhibited the mRNA expression of TLR2 and tumor necrotic factor-α in the ileum (P ≤ 0.05).ConclusionsThe dietary supplementation of EO could alleviate the intestinal injury by improving intestinal integrity and modulating immune responses in the C. perfringens-challenged broiler chickens.

Thymol, thyme, and other plant sources: Health and potential uses

“…Although in some of these studies, the data did not indicate a clear positive effect of thyme on animal performance; it seems that the effects of thymol may depend on the diet formulation and the environment (Haselmeyer et al, ). However, other effects of thymol have been reported at intestinal levels such as intestinal injury by improving intestinal integrity and modulating immune responses in chickens infected with Clostridium perfringens (Du et al, ).…”

Bacillus subtilis B21 and Bacillus licheniformis B26 improve intestinal health and performance of broiler chickens with Clostridium perfringens‐induced necrotic enteritis

“…Reduced TJ integrity greatly increases ion conductance across the paracellular route resulting in a leaky gut, Tomita and Hayashi (). It was shown that broiler challenged with C. perfringens resulted in decrease of claudin‐1 and occludin gene expression and however disrupted the TJs between the epithelial cells Du et al (). Similarly, Li et al () discovered that C. perfringens challenged chickens decreased occludin mRNA expression in the jejunum.…”

Over-expression of Toll-like receptor 2 up-regulates heme oxygenase-1 expression and decreases oxidative injury in dairy goats

“…During infection, the innate immune system of the host animal provides the first line of defense in pathogen recognition, and pattern recognition receptors (PRRs) are necessary for this process to occur. Toll-like receptor (TLR) 2 plays a critical role in recognition of the conserved portion of Gram-positive bacteria [2], and it is known that mastitis can increase expression of the TLR2 gene in mammary glands [3]. Genetic diversity in the TLR2 gene is a risk factor for staphylococcus infection [4], and TLR2−/− mice are susceptible to S. aureus [5].…”