Clostridium perfringens is the causative pathogen of avian necrotic enteritis. Lactobacillus spp. are well-characterized probiotics with anti-microbial and immune-modulatory activities. In the present study, we investigated the effects of L. acidophilus and L. fermentum on the growth, α-toxin production and inflammatory responses of C. perfringens. In in vitro culture experiments, both lactobacilli inhibited the growth of C. perfringens (P < 0.01), accompanied with a decrease in pH (P < 0.01). Supernatants from lactobacilli cultures also suppressed the growth of C. perfringens during 24 h of incubation (P < 0.01), but this inhibitory effect disappeared after 48 h. Both lactobacilli decreased the α-toxin production of C. perfringens (P < 0.01) without influencing its biomass, and even degraded the established α-toxin (P < 0.01). Lower environmental pH reduced the α-toxin production as well (P < 0.01). Preincubation with L. acidophilus decreased the attachment of C. perfringens to cells (P < 0.01) with the cell cytotoxicity being unaffected. Both lactobacilli pretreatment reduced the up-regulation of proinflammatory factors, peptidoglycan (PGN) receptors and nuclear factor kappa B (NF-κB) p65 in C. perfringens-challenged chicken intestinal epithelial cells (P < 0.05). In conclusion, L. acidophilus and L. fermentum inhibited the pathological effects of C. perfringens in vitro conditions.

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Oleum cinnamomi (OCM) is increasingly used as a feed additive in animal diets. The aim of this study was to investigate the effects of dietary supplementation with coated-OCM (cOCM) on the immunity and intestinal integrity of broiler chickens. A total of 396 one-day-old chicks were randomly assigned into six groups. The basal diets were supplemented with 50 mg/kg of flavomycin (positive control) as well as 0 (control), 50, 100, 200, and 300 mg/kg of cOCM. Compared with the control, both positive control and cOCM treatments did not improve the growth performance. Serum immunoglobulin (Ig) Y levels were decreased by flavomycin and 50 mg/kg of cOCM treatments (p < 0.05). Dietary cOCM decreased ileal secretory IgA contents at d 21 and commonly down-regulated duodenal and ileal mRNA expression of interleukin (IL)-1β and IL-8 at d 42 (p < 0.05). The 300 mg/kg of cOCM increased jejunal ratio of villus height to crypt depth and upregulated intestinal claudin-1 expression (p < 0.05). Jejunal (at d 21) and duodenal (at d 42) mucin-2 expression was up and downregulated by both 50 and 300 mg/kg of cOCM, respectively (p < 0.05). In conclusion, dietary cOCM addition helped to maintain noninflammatory states of humoral and mucosal immunity, and improved the intestinal integrity of broiler chickens.

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Permian cherts are widely developed in the Sichuan Basin and carry significant information about the evolution of the sedimentary environment. To understand the origins and depositional environments of the Middle–Upper Permian cherts in the Sichuan Basin, we studied the lithological and geochemical characteristics of the cherts. Based on field observations and thin section analysis, Permian cherts occur mainly in the form of nodular and bedded cherts. Nodular cherts present irregular lumps or tuberculous patterns and are composed of mostly cryptocrystalline and microcrystalline quartz with small amounts of carbonate mineral. Bedded cherts contain organic matter, and radiolarians can be found in Late Permian bedded cherts. The geochemical analysis of Permian cherts shows that the chert sources are complex; nodular Middle Permian cherts show hydrothermal and upwelling influences, with less terrestrial influence. Nodular chert is the product of diagenetic metasomatism, formed when silica‐rich fluids entered carbonate that was partially dissolved by H+ released from the oxidation of H2S. Bedded cherts of the Maokou Formation have the same source as nodular cherts but were deposited in a slope or depression of the platform, which was below the CaCO3 compensation depth (CCD) interface, so that bedded chert could be deposited directly. Bedded cherts of the Wujiaping Formation show influence from hydrothermal, biogenetic, and terrestrial sources and were deposited in a deeper water environment, such as basin or the bottom of slope. The Permian cherts in the Sichuan Basin are the response to the global Permian Chert Event (PCE), which was closely related to the Late Palaeozoic Ice Age (LPIA) and the global active volcanism during the Permian.