The palatine tonsils play a pivotal role in porcine upper respiratory tract immunity by acting as an interface between the host and the external environment. As such, the tonsillar microbiota represents a critical yet insufficiently characterized microbial ecosystem. This review provides an overview of current knowledge on the porcine tonsillar microbiota, beginning with a description of sampling strategies and laboratory approaches, including metabarcoding, shotgun metagenomics, and culturomics. The development of the tonsillar microbiota over time and the main environmental, host-related, and management factors shaping its composition are examined. Particular emphasis is placed on the core bacterial communities commonly identified in the palatine tonsils, which are largely dominated by members of the Pasteurellaceae, Streptococcaceae, and Moraxellaceae families. The review further discusses how infectious and non-infectious diseases can disrupt tonsillar microbial homeostasis, as well as the effects of antimicrobial treatments, vaccination, and other prophylactic interventions on microbial structure and function. Finally, methodological biases inherent to current studies are highlighted, key knowledge gaps are identified, and future research directions are proposed to advance metagenomic investigations and better elucidate the role of the tonsillar microbiota in swine health and disease.
β-defensin 130 is a potential antimicrobial peptide candidate against enterotoxigenic Escherichia coli (ETEC)-K88 infection, but its in vivo mechanism remains unclear. In this study, the antibacterial activity of β-defensin 130 against ETEC-K88 was first evaluated in vitro, and membrane damage was observed by morphological disruption and PI uptake. Then, an ETEC-K88-infected mouse model was established and treated with β-defensin 130. Based on 16 S rDNA sequencing and LC-MS metabolomics, ETEC-K88 infection was shown to reduce gut microbial diversity and alter community structure. Correlation analysis revealed significant microbiota-metabolite interactions, β-defensin 130 treatment was associated with increased gut microbial diversity and partial recovery of the gut microbial community, increased beneficial Bacteroidota/Firmicutes, decreased pathogenic Proteobacteria, and partial reversal of infection-associated metabolic disturbances (e.g., upregulating L-tryptophan and linoleic acid). Collectively, these findings suggest that β-defensin 130 may alleviate ETEC-K88 infection by disrupting bacterial membranes, modulating gut microbiota, and partially restoring metabolic homeostasis, supporting its further development as a potential antimicrobial agent.
Postbiotics, the bioactive molecules of probiotics and inactive microbial cells, have emerged as promising supplementary method in dental health treatment, specifically targeting disorders such as periodontitis. The definition, mechanisms of action and therapeutic potential of postbiotics in periodontitis are discussed in detail in this review. The capacity of postbiotics to control pathogenic bacteria development, increase immune responses and restore microbial balance, demonstrates the many roles of postbiotics in antimicrobial activity and anti-inflammatory effects in controlling the oral microbiome. Importantly, postbiotics have potential advantages over live probiotics such as greater stability and safety, without the need for microbial colonization. Postbiotics have shown potential in reducing gingival inflammation, as evidenced by clinical studies, thus offering a promising adjunct to conventional periodontal therapies. Current data, however, are limited, heterogeneous, and insufficient to support strong therapeutic claims. As research advances, the standardized addition of postbiotics to common dental care and hygiene products needs to be rigorously validated by large-scale clinical trials.
Newcastle disease virus (NDV) causes substantial losses in poultry, and nonchemical approaches for reducing viral infectivity warrant investigation. Ultrafast femtosecond (fs) lasers offer a novel, non-thermal, and photosensitizer-free approach to pathogen inactivation. The primary aim of this study was to evaluate the wavelength-dependent efficacy of femtosecond laser irradiation (370–420 nm) in inactivating NDV, establishing a proof-of-concept for non-chemical viral attenuation using embryonated chicken eggs (ECEs) as a biological model. NDV suspensions were irradiated with 100 fs laser pulses at 370, 385, 400, and 420 nm for 60 min. The treated virus samples (100 µl) were inoculated into specific-pathogen-free (SPF) embryonated chicken eggs at dilutions of 10⁵, 10⁷ and 10⁹ and the viability of the embryo was monitored. Viral infectivity was assessed by embryo mortality and hemagglutination (HA) assays over 168 h. Exposure to 370 nm laser light resulted in > 99.99
