BACKGROUND: Bovine mastitis is one of the main causes of reduced production in dairy cows. The infection of the mammary gland is mainly caused by the bacterium Staphylococcus aureus, whose resistant strains make the treatment of mastitis with conventional antibiotics very difficult and result in high losses. Therefore, it is important to develop novel therapeutic agents to overcome the resistance of mastitis-causing strains. In this study, novel selenium-tellurium based nanoparticles (SeTeNPs) were synthesized and characterized. Their antibacterial activity and biocompatibility were evaluated both in vitro and in vivo using a bovine model. A total of 10 heifers were divided into experimental and control groups (5 animals each). After intramammary infection with methicillin resistant S. aureus (MRSA) and the development of clinical signs of mastitis, a dose of SeTeNPs was administered to all quarters in the experimental group. RESULTS: Based on in vitro tests, the concentration of 149.70 mg/L and 263.95 mg/L of Se and Te, respectively, was used for application into the mammary gland. Three days after SeTeNPs administration, MRSA counts in the experimental group showed a significant reduction (P < 0.01) compared to the control group. The inhibitory effect observed within the in vitro experiments was thus confirmed, resulting in the suppression of infection in animals. Moreover, the superior biocompatibility of SeTeNPs in the organism was demonstrated, as the nanoparticles did not significantly alter the inflammatory response or histopathology at the site of application, i.e., mammary gland, compared to the control group (P > 0.05). Additionally, the metabolic profile of the blood plasma as well as the histology of the main organs remained unaffected, indicating that the nanoparticles had no adverse effects on the organism. CONCLUSIONS: Our findings suggest that SeTeNPs can be used as a promising treatment for bovine mastitis in the presence of resistant bacteria. However, the current study is limited by its small sample size, making it primarily a proof of the concept for the efficacy of intramammary-applied SeTeNPs. Therefore, further research with a larger sample size is needed to validate these results.

• Keywords
• Antibacterial, Biocompatibility, Heifer, Intramammary, MRSA, Mammary gland, Nanomaterial, Resistance, SeTe,
• Publication type
• Journal Article MeSH

Balanced bacterial metabolism is essential for cell homeostasis and growth and can be impacted by various stress factors. In particular, bacteria exposed to metals, including the nanoparticle form, can significantly alter their metabolic processes. It is known that the extensive and intensive use of food and feed supplements, including zinc, in human and animal nutrition alters the intestinal microbiota and this may negatively impact the health of the host. This study examines the effects of zinc (zinc oxide and zinc oxide nanoparticles) on key metabolic pathways of Escherichia coli. Transcriptomic and proteomic analyses along with quantification of intermediates of tricarboxylic acid (TCA) were employed to monitor and study the bacterial responses. Multi-omics analysis revealed that extended zinc exposure induced mainly oxidative stress and elevated expression/production of enzymes of carbohydrate metabolism, especially enzymes for synthesis of trehalose. After the zinc withdrawal, E. coli metabolism returned to a baseline state. These findings shed light on the alteration of TCA and on importance of trehalose synthesis in metal-induced stress and its broader implications for bacterial metabolism and defense and consequently for the balance and health of the human and animal microbiome.

• Keywords
• Carbohydrate metabolism, Nanoparticles, Proteome, Transcriptome, Trehalose synthesis, Tricarboxylic acid cycle, Virulence, Zinc, Zinc oxide,
• MeSH
• Citric Acid Cycle * drug effects   MeSH
• Escherichia coli * metabolism   genetics   drug effects   MeSH
• Adaptation, Physiological MeSH
• Metabolic Networks and Pathways drug effects   MeSH
• Zinc Oxide metabolism   pharmacology   MeSH
• Oxidative Stress MeSH
• Escherichia coli Proteins metabolism   genetics   MeSH
• Proteomics MeSH
• Gene Expression Regulation, Bacterial drug effects   MeSH
• Gene Expression Profiling MeSH
• Transcriptome MeSH
• Trehalose * metabolism   MeSH
• Zinc * metabolism   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Zinc Oxide MeSH
• Escherichia coli Proteins MeSH
• Trehalose * MeSH
• Zinc * MeSH

A long-term exposure of bacteria to zinc oxide and zinc oxide nanoparticles leads to major alterations in bacterial morphology and physiology. These included biochemical and physiological processes promoting the emergence of strains with multi-drug resistance and virulence traits. After the removal of zinc pressure, bacterial phenotype reversed back to the original state; however, certain changes at the genomic, transcriptomic, and proteomic level remained. Why is this important? The extensive and intensive use of supplements in animal feed effects the intestinal microbiota of livestock and this may negatively impact the health of animals and people. Therefore, it is crucial to understand and monitor the impact of feed supplements on intestinal microorganisms in order to adequately assess and prevent potential health risks.

• Keywords
• antimicrobial resistance, genome, nanoparticles, phenotype, proteome, transcriptome, virulence, zinc, zinc oxide,
• MeSH
• Escherichia coli genetics   MeSH
• Humans MeSH
• Multiomics MeSH
• Zinc Oxide * chemistry   MeSH
• Proteomics MeSH
• Zinc * pharmacology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Zinc Oxide * MeSH
• Zinc * MeSH

BACKGROUND: Bentonites, as a clay mineral, serve in pig farms as adsorbents of toxic substances. They are mainly used to reduce the negative impact of mycotoxins to maintain the performance and health status of animals. The new genotypes of pigs are highly sensitive to a range of antinutrients, including mycotoxins. Currently, attention is focused on more effective adsorbents of mycotoxins with a higher adsorption capacity. Such materials are in great demand among feed manufacturers. However, there is a concern that these new materials may also adsorb too many essential nutrients and decrease animal performance. The aim of the experiment was to evaluate the effect of the new generation of purified bentonites on the efficiency and health status of the pigs. RESULTS: Forty-eight slaughtered pigs with an average weight of 31.2 ± 2.6 kg were included in the experiment. The pigs were divided into two groups (2 × 24 pigs). Pigs were slaughtered at an average weight of 66.3 ± 5.2. The first group had a diet without clay (control-C). The second group (treatment-T) was fed a diet with a clay additive (purified bentonite) of 1.5 kg/t. Animals were fed the experimental diet for 35 days. In group T, a higher daily weight gain (by 4.8%) and feed intake (by 2.9%) was observed while the feed conversion decreased by 1.9%. There were no significant differences between the groups of pigs during observation in the evaluation of hematological, biochemical parameters of the blood. Morpho-pathological analysis of the jejunum showed similar signs of moderate lymphoplasmacytic infiltrate in the mucosa in the groups C and T, contained similar number of goblet cells. CONCLUSION: Taken together, the addition of the new generation of bentonite clays did not negatively influence the health status and the performance of pigs.

• Keywords
• Bentonite, Growth performance, Health status, Histopathology,
• Publication type
• Journal Article MeSH

The scientific community is closely monitoring the replacement of antibiotics with doses of ZnO in weaned piglets. Since 2022, the use of zinc in medical doses has been banned in the European Union. Therefore, pig farmers are looking for other solutions. Some studies have suggested that zinc nanoparticles might replace ZnO for the prevention of diarrhea in weaning piglets. Like ZnO, zinc nanoparticles are effective against pathogenic microorganisms, e.g., Enterobacteriaceae family in vitro and in vivo. However, the effect on probiotic Lactobacillaceae appears to differ for ZnO and zinc nanoparticles. While ZnO increases their numbers, zinc nanoparticles act in the opposite way. These phenomena have been also confirmed by in vitro studies that reported a strong antimicrobial effect of zinc nanoparticles against Lactobacillales order. Contradictory evidence makes this topic still controversial, however. In addition, zinc nanoparticles vary in their morphology and properties based on the method of their synthesis. This makes it difficult to understand the effect of zinc nanoparticles on the intestinal microbiome. This review is aimed at clarifying many circumstances that may affect the action of nanoparticles on the weaning piglets' microbiome, including a comprehensive overview of the zinc nanoparticles in vitro effects on bacterial species occurring in the digestive tract of weaned piglets.

• Keywords
• antibiotic replacement, antimicrobial effects, diarrhea, gastro-intestinal tract, microbiome, nanotechnology, piglets' weaning, zinc oxide,
• Publication type
• Journal Article MeSH
• Review MeSH

The study aimed to investigate the efficacy of new mycotoxin adsorbents based on purified and activated bentonites combined with yeast and phytogenic compounds in fattening pigs. The experiment involved 96 pigs (31.2±2.4 kg). Control (C) group was fed a diet naturally contaminated with mycotoxins (5 mg/kg deoxynivalenol, DON) without an adsorbent. Treated groups received the feed with mycotoxin adsorbents: purified and activated bentonite (T1), purified and activated bentonite, yeast derivatives, phytogenic substances (T2), and purified, activated, and sulphurated bentonite with phytogenic substances (T3). Evaluated parameters involved growth performance, organ weight, small intestine and liver histopathology, complete blood count, serum biochemistry, antioxidant status of the organism and total and free DON content in urine. In all treated groups, an significant increase in intestinal GSH and GSH/GSSG ratio was observed when compared to C. No significant effects on liver and kidney weight, complete blood count, serum or intestinal malondialdehyde concentration, or total/free DON content in urine were observed. All adsorbents improved histopathological findings in the liver when compared to C. Moreover, T1, and T2 groups showed no presence of inflammatory reaction or necrotic changes in the livers. Although, mycotoxin adsorbents investigated in this study had no significant impact on pig growth performance, they reduced the oxidative stress, and on the tissue level they protected the jejunal tissue and liver parenchyma under deoxynivalenol challenge.

• MeSH
• Antidotes * administration & dosage   pharmacology   MeSH
• Bentonite * administration & dosage   pharmacology   MeSH
• Food Contamination analysis   MeSH
• Animal Feed * analysis   microbiology   MeSH
• Mycotoxins adverse effects   MeSH
• Swine MeSH
• Intestine, Small drug effects   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Antidotes * MeSH
• Bentonite * MeSH
• Mycotoxins MeSH