The C. perfringens species is associated with various environments, such as soils, sewage, and food. However, it is also a component of the gastrointestinal (GI) microflora (i.e., microbiota) of sick and healthy humans and animals. C. perfringens is linked with different systemic and enteric diseases in livestock and humans, such as gas gangrene, food poisoning, non-foodborne diarrhoea, and enterocolitis. The strains of this opportunistic pathogen are known to secrete over 20 identified toxins that are considered its principal virulence factors. C. perfringens belongs to the anaerobic bacteria community but can also survive in the presence of oxygen. The short time between generations, the multi-production capability of toxins and heat-resistant spores, the location of many virulence genes on mobile genetic elements, and the inhabitance of this opportunistic pathogen in different ecological niches make C. perfringens a very important microorganism for public health protection. The epidemiological evidence for the association of these strains with C. perfringens–meditated food poisoning and some cases of non-foodborne diseases is very clear and well-documented. However, the genetic diversity and physiology of C. perfringens should still be studied in order to confirm the importance of suspected novel virulence traits. A very significant problem is the growing antibiotic resistance of C. perfringens strains. The aim of this review is to show the current basic information about the toxins, epidemiology, and genetic and molecular diversity of this opportunistic pathogen.

The diversity of BoNT-producing Clostridia is still a worrying problem for specialists who explore the evolutionary and taxonomic diversity of C. botulinum. It is also a problem for epidemiologists and laboratory staff conducting investigations into foodborne botulism in humans and animals, because their genetic and phenotypic heterogeneity cause complications in choosing the proper analytical tools and in reliably interpreting results. Botulinum neurotoxins (BoNTs) are produced by several bacterial groups that meet all the criteria of distinct species. Despite this, the historical designation of C. botulinum as the one species that produces botulinum toxins is still exploited. New genetic tools such as whole-genome sequencing (WGS) indicate horizontal gene transfer and the occurrence of botulinum gene clusters that are not limited only to Clostridium spp., but also to Gram-negative aerobic species. The literature data regarding the mentioned heterogeneity of BoNT-producing Clostridia indicate the requirement to reclassify C. botulinum species and other microorganisms able to produce BoNTs or possessing botulinum-like gene clusters. The aim of this study was to present the problem of the diversity of BoNT-producing Clostridia over time and new trends toward obtaining a reliable classification of these microorganisms, based on a complex review of the literature.

Introduction: Heat treatment is indispensable in fish canning to provide an acceptable shelf life. Its optimisation reduces the risk of the presence of Clostridium botulinum spores, which could potentially cause botulism cases. This study evaluated canned fish samples for botulism neurotoxin (BoNT)-producing clostridia contamination and can bulging through microbiological contaminant growth. A new analytical approach was developed for detection of such clostridia and phenotypically similar species. Material and Methods: A total of 70 canned fish samples suspected of exhibiting bulging features were analysed. Culture methods were used to detect clostridia. The isolates obtained were evaluated on the basis of the exhibited phenotypic characteristics. Also, PCRs were used for the detection of genes determining BoNT production (non-toxic non-haemagglutinin (ntnh) genes) and the amplification of conservative 16S rDNA genes, which were Sanger sequenced. The obtained sequences were analysed using the Basic Local Alignment Search Tool. Results: Clostridium genus species were isolated from 17 (24%) bulging and organoleptically changed samples. No ntnh genes were present in these isolates; however, sequencing confirmed the presence of C. sporogenes, a species with close affinity to C. botulinum. Conclusion: To eliminate the threat of foodborne botulism, laboratory diagnostic techniques must detect species of the Clostridium genus and elucidate their ability to produce BoNTs. Although Clostridium botulinum is the most common cause of botulism, the possibility may not be ignored that non-pathogenic Clostridium species may acquire botulinum toxigenicity. The similarity between the isolated strains of C. sporogenes and C. botulinum should be incorporated in the optimisation of heat treatment to guarantee a sterilised, microbiologically safe product.

Allicin is a chemically complex bioactive compound synthesized in many varieties of garlic. The wide range of biological properties of allicin provides the basis for its potential use as an alternative to antibiotic growth promoters that are currently prohibited in farm animal breeding. Among the many benefits resulting from the use of allicin in animal breeding, especially poultry, its modulating effect on intestinal microbiota, which includes the anaerobic spore-forming bacteria of the genus Clostridium spp., seems to be important. The material for this study consists of intestinal content collected from the caecums of Japanese quails (Coturnix japonica). Culture methods were used to isolate the strains, and the obtained isolates were identified based on their phenotypic characteristics. In addition, PCR methods were used for the detection of the ntnh gene-encoding non-haemagglutinin component of botulinum neurotoxins (BoNTs), the detection of individual genes responsible for the production of major toxins by Clostridium perfringens, and the amplification of conservative 16S rDNA genes. The 16S rDNA amplicons were subsequently submitted to Sanger sequencing. The obtained sequences were analyzed using the Basic Local Alignment Search Tool (BLAST). The ntnh gene was not found in the genetic material of the isolated strains. Among the isolates suspected of belonging to the Clostridium perfringens species, the plc gene determining the production of the alpha toxin was detected, which justifies the classification of the strains into toxotype A. The Sanger sequencing results confirm the presence of mainly saprophytic species in the studied material. The statistical analysis indicated a statistically significant reduction in the level of Clostridium spp., obtained by the use of an appropriate dose of allicin. The presented research results indicate the significant impact of an appropriate dose of allicin on reducing the occurrence of anaerobic intestinal microbiota, while providing important information on the potential application of this compound in animal production in the future.

Allicin is a sulphur-containing bioactive compound naturally synthesised in several Allium species, including white garlic ( Allium sativum L.), bear garlic ( Allium ursinum L.) and field garlic ( Allium vineale L.). Current literature indicates that allicin exhibits a wide range of therapeutic activities, most notably antimicrobial, antiparasitic, antioxidant, antiviral and antifungal effects. Its biological action is primarily driven by two key mechanisms: rapid penetration into pathogenic cells and the induction of lethal intracellular alterations. The breadth of allicin’s biological properties has prompted growing interest in its potential applications in the livestock industry. Dietary supplementation with allicin has been associated with improved growth performance, enhanced immune function, better quality of animal-derived products and favourable modulation of the intestinal microbiota – an aspect of particular relevance because of the central role of gut microorganisms in animal health. The aim of this review is to summarise current knowledge on the biological properties of allicin, and to particularly consider its effects on intestinal microbial modulation and its potential to improve the production efficiency of livestock.

Botulism is a neuroparalytic disease caused by exposure to botulinum neurotoxins produced by anaerobic spore-forming bacteria of the genus Clostridium. This disease occurs in both humans and wild and domestic animals, and is currently becoming an increasingly serious problem worldwide due to high animal mortality and economic losses. The clinical signs observed during the progression of botulism are nonspecific and difficult to unequivocally associate with this disease entity. The aim of this study is to present laboratory diagnostics of suspected botulism cases reported in Poland in 2022–2024, as well as to present the challenges encountered during laboratory investigations. The material for the study consisted of samples of liver, serum, digestive tract, feed, feces, straw, and water from drinking lines, sent to the National Veterinary Research Institute (NVRI) in relation to thirteen suspected cases of botulism, predominantly reported in poultry, but also in mink and cattle farms. The samples were analyzed using a mouse bioassay and conventional culture methods, as well as real-time PCR methods aimed at detecting the ntnh and bont genes, which determine the production of botulinum neurotoxins. Of the thirteen suspected cases analyzed, ten were confirmed by the detection of botulinum toxin (BoNTs) and/or the presence of the ntnh and bont genes in the tested material. Based on the results obtained, it was concluded that botulinum toxin type C was the etiological factor of botulism poisoning in most of the analyzed cases. In one case reported in cattle, poisoning occurred as a result of the mosaic variant of BoNT D/C. Due to the nonspecific signs of botulism and the time required for them to appear, laboratory diagnostics play a key role in detecting the disease. However, this process is complicated due to the high heterogeneity observed among Clostridium spp. strains, as well as difficulties encountered during the isolation of the microorganism and the possibility of loss of toxin-producing capacity at later stages of analysis.