In recent decades, nanotechnology has been rapidly advancing in various fields of human activity, including veterinary medicine. The review presents up-to-date information on recent advancements in nanotechnology in the field and an overview of the types of nanoparticles used in veterinary medicine and animal husbandry, their characteristics, and their areas of application. Currently, a wide range of nanomaterials has been implemented into veterinary practice, including pharmaceuticals, diagnostic devices, feed additives, and vaccines. The application of nanoformulations gave rise to innovative strategies in the treatment of animal diseases. For example, antibiotics delivered on nanoplatforms demonstrated higher efficacy and lower toxicity and dosage requirements when compared to conventional pharmaceuticals, providing a possibility to solve antibiotic resistance issues. Nanoparticle-based drugs showed promising results in the treatment of animal parasitoses and neoplastic diseases. However, the latter area is currently more developed in human medicine. Owing to the size compatibility, nanomaterials have been applied as gene delivery vectors in veterinary gene therapy. Veterinary medicine is at the forefront of the development of innovative nanovaccines inducing both humoral and cellular immune responses. The paper provides a brief overview of current topics in nanomaterial safety, potential risks associated with the use of nanomaterials, and relevant regulatory aspects.
16 June 2023 in Acta Microbiologica Et Immunologica Hungarica
Objectives: Methicillin-resistant Staphylococcus (MRS) has originated, spread extensively, and become a prominent source of bacterial infections in both human and animal.Methods: We report the prevalence, genetic diversity, and antimicrobial resistance pattern of Staphylococcus pseudintermedius and Staphylococcus aureus strains isolated from dogs and cats with eye discharges.Results: A total of 12 (6.0%) coagulase-positives staphylococci were identified as (6/200, 3%) S. aureus and (6/200, 3%) S. pseudintermedius. The phenotypic methicillin resistance of S. aureus and S. pseudintermedius were 50.0% (3/6) and 16.7% (1/6), respectively. None of the isolates showed biofilm formation in the microtiter plate assay. The highest resistance (50.0%) for S. pseudintermedius strains was detected against clindamycin and tetracycline. 67.0% of S. aureus isolates were resistant to penicillin-G. The PCR analysis conducted for detection of mecA gene indicated that only one S. aureus isolated from a cat was mecA gene positive. Phylogenetic analysis based on repetitive sequence-based PCR (rep-PCR) showed that all strains were typable and generated PCR products ranging from 800 bp to 4,400 bp. The lineages ST241 and the novel ST2361 in multi-locus sequence typing (MLST) analysis were detected in one methicillin-susceptible S. pseudintermedius and methicillin-resistant S. pseudintermedius of dogs, respectively. In addition, the lineages ST4155 and ST7217 of two methicillin-resistant S. aureus strains of cats were connected epidemiologically to previously reported cases.Conclusions: These results indicate epidemiologically related strains (ST241, ST4155, and ST7217) transferring between animals and humans. Therefore, the strategies to combat the widespread MRS should be based on collaboration between human and veterinary medicine under the One Health concept.
1 September 2020 in Ankara Üniversitesi Veteriner Fakültesi Dergisi
Microorganisms have a primary role in the formation of calf diarrhea. Escherichia coli pose an environmental risk to young animals caused by fecal excretion. In this study, rectal swab samples (n= 133) were collected from calves with diarrhea aged from 1 day to 3 months, between August 2017 and August 2018. The samples were cultured on MacConkey agar, and then antimicrobial susceptibility and virulence genes for Escherichia coli isolates (n= 133) were investigated by disk diffusion method according to clinical and laboratory standards institute standards and multiplex polymerase chain reaction, respectively. The isolates were found to be highly resistant to oxytetracycline (78.9%), trimethoprim-sulfamethoxazole (69.2%), neomycin (60.9%), and erythromycin (58.6%). Besides, multidrug resistance was determined in 71.4% of isolates. Thirty-three of 133 (24.81%) isolates were positive for at least one virulence factor. The pathotypes of enterotoxigenic Escherichia coli (F5 and/or F41 fimbria and STa), enterohemorrhagic Escherichia coli (Stx and eae), enteropathogenic Escherichia coli (eae) and Shiga toxin-producing Escherichia coli (Stx-eae) were found in 51.5%, 6.1%, 15.2%, and 12.1%, respectively. However, the virulence properties were detected as; Stx1 (3.03%), Stx2 (9.09%), STa (21.21%), and eae (15.15%); the F41 and F5 were not detected. Also, the fifteen-point two percent of strains (5/33) were the hybrid type that carried both Stx (either Stx1 or Stx2) and enterotoxigenic Escherichia coli specific enterotoxin gene STa. The existence of different virulence factors found in this study supports the statement that calves are possible bearers of pathogens that are dangerous to public health.
30 March 2017 in Journal of the South African Veterinary Association
Bedding material, which is a significant part of rodent housing, affects the health and well-being of laboratory animals. The aim of this study was to evaluate perlite as a bedding material for rodents and to compare it with wood shavings, expanded perlite and corncobs. The animals used in this experiment were 48 male and 48 female Sprague-Dawley rats. The bedding materials collected from experimental groups were analysed microbiologically. Blood samples from rats were subjected to biochemical analysis for catalase, glutathione, glutathione peroxidase, malondialdehyde, superoxide and dismutase, and foot pad skins of rats were subjected to histopathological examination. Body weight was determined at the end of the 30-day period. Perlite as the only bedding material had no effect on body weight, and it resulted in less microbial activity compared with the wood shavings, expanded perlite and corncobs. However, using perlite alone had negative effects on the skin, the moisture percentage of bedding and stress parameters. A wood shavingsperlite combination gave better results than perlite alone and appropriate perlite and other bedding material mixtures may result in bedding materials conducive to animal health and welfare. The frequency of changing the bedding material should be limited to once weekly.
To aid development of phage therapy against Campylobacter, we investigated the distribution of the clustered regularly interspaced short palindromic repeats (CRISPR) systems in fluoroquinolone (FQ)-resistant Campylobacter jejuni. A total of 100 FQ-resistant C. jejuni strains from different sources were analyzed by PCR and DNA sequencing to determine resistance-conferring mutation in the gyrA gene and the presence of various CRISPR systems. All but one isolate harbored 1–5 point mutations in gyrA, and the most common mutation was the Thr86Ile change. Ninety-five isolates were positive with the CRISPR PCR, and spacer sequences were found in 86 of them. Among the 292 spacer sequences identified in this study, 204 shared 93–100% nucleotide homology to Campylobacter phage D10, 44 showed 100% homology to Campylobacter phage CP39, and 3 had 100% homology with Campylobacter phage CJIE4-5. The remaining 41 spacer sequences did not match with any phages in the database. Based on the results, it was inferred that the FQ-resistant C. jejuni isolates analyzed in this study were potentially resistant to Campylobacter phages D10, CP39, and CJIE4-5 as well as some unidentified phages. These phages should be excluded from cocktails of phages that may be utilized to treat FQ-resistant Campylobacter.
Milk is commonly screened both for indicators of animal disease and health, but also for foodborne hazards. Included in these analyses is the detection of Staphylococcus aureus, that can produce an enterotoxin, causing staphylococcal food poisoning (SFP), which often leads to sudden onset of significant gastrointestinal symptoms in humans. Epidemiological data on SFP are limited, particularly in low- and middle-income countries. Many conventional assays for the detection of staphylococcal enterotoxins rely on the detection of the genes coding for them, either directly in food samples or after bacterial culture. Currently, many of the nucleic acid-based methods used require specific expertise and equipment, whilst bacterial culture takes 24–48 hours; both are contributory factors that limit efforts either during food safety emergencies or routine screening. Here we present the development of a “sample-to-answer” isothermal nucleic acid loop-mediated amplification (LAMP) assay in a microfluidic device for the detection of Staphylococcus aureus enterotoxin genes in ruminant milk. A multiplex LAMP assay targeting two of the most prevalent S. aureus enterotoxin-encoding genes (A and B) was integrated into a microfluidic device combining simple 1 : 10 dilution for sample preparation and a lateral flow assay for easy readout. We achieved a limit of detection of 104 colony forming units per ml in spiked cow and goat milk samples, an order of magnitude more sensitive than the European recommendation for the maximum allowable presence of coagulase-positive staphylococci in raw milk. The assay showed no cross-reactivity in detecting other tested non-enterotoxigenic S. aureus strains or associated foodborne pathogens. The test integrated the simplicity of use of microfluidic devices with the sensitivity, specificity and rapidity of a nucleic acid-based assay, and a simple lateral flow readout to provide an appropriate device to ensure the safety of milk for human consumption. To illustrate its potential for point-of-need practical applications, the test was performed in agricultural settings in rural Turkey in a limited feasibility exercise.