A Chinese herbs complex ameliorates gut microbiota dysbiosis induced by intermittent cold exposure in female rats

Cold exposure, gut microbiota and health implications: A narrative review

Temperature has been recognized as an important environmental factor affecting the composition and function of gut microbiota (GM). Although research on high-temperature impacts has been well studied, knowledge about the effect of cold exposure on GM remains limited. This narrative review aims to synthesize the latest scientific findings on the impact of cold exposure on mammalian GM, and its potential health implications. Chronic cold exposure could disrupt the α-diversity and the composition of GM in both experimental animals and wild-living hosts. Meanwhile, cold exposure could impact gut microbial metabolites, such as short-chain fatty acids. We also discussed plausible biological pathways and mechanisms by which cold-induced changes may impact host health, including metabolic homeostasis, fitness and thermogenesis, through the microbiota-gut-brain axis. Intriguingly, alterations in GM may provide a tool for favorably modulating the host response to the cold temperature. Finally, current challenges and future perspectives are discussed, emphasizing the need for translational research in humans. GM could be manipulated by utilizing nutritional strategies, such as probiotics and prebiotics, to deal with cold-related health issues and enhance well-being in populations living or working in cold environments.

Effects of Bacillus licheniformis on growth performance, immune and antioxidant functions, and intestinal microbiota of broilers

Bacillus licheniformis (BL) has been widely regarded as an important growth promoter in recent years. However, its usage in animal industry still needs more foundations. The aim of our study was to study the effects of BL on the growth performance, immunity, oxidative function and intestinal flora of broilers. A total of 760 one-day-old yellow-feathered broilers were randomly divided into 4 groups with 10 replicates per group and 19 broilers per replicate. The broilers in the control group (CON) were fed with basal diet. The treatment groups were supplemented with 250 mg/kg (BL250), 500 mg/kg (BL500) and 750 mg/kg (BL750) BL in the basal diet for 70 d. Results showed that BL groups significantly increased the body weight (BW) and average daily gain (ADG), decreased average daily feed intake (ADFI) and feed conversion ratio (FCR). In addition, the spleen and bursa indexes were higher in the BL groups than that in the CON group at d 70. BL supplementation also markedly increased the levels of immunoglobulins Y (IgY), IgA and anti-inflammatory interleukin 10 (IL-10), reduced the levels of proinflammatory IL-1β, tumor necrosis factor α (TNF-α) and IL-2 in the serum at 70 d in a concentration-dependent manner. Besides, BL addition significantly increased the levels of series antioxidant enzymes including total antioxidant capacity (T-AOC), glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase (CAT), and decreased the level of malondialdehyde (MDA) in the serum. Moreover, BL groups showed an obvious increase of isobutyric acid markedly and BL500 group significantly promoted the level of isovaleric acid in cecal contents of broilers. Finally, microbial analysis showed that BL supplementation presented visual separations of microbial composition and increased the relative abundance of p_Proteobacteria, g_Elusimicrobium, and g_Parasutterella comparing with the CON group. Together, this study inferred that dietary BL supplementation improved the growth performance, immune and antioxidant functions, changed the intestinal microflora structure and metabolites of yellow-feathered broilers, which laid a good basis for the application of probiotics in the future.