Detection and Genomic Characterization of Senecavirus from Indian Pigs

Background: Senecavirus A (SVA), is a positive sense small non-enveloped RNA virus which belongs to Picornaviridae family and is responsible for porcine vesicular disease. The disease has been reported in many countries since late 2014, 2015 and 2016 like USA, Canada, Brazil, China and Thailand. Methods: In this study, the metagenomic study was performed on faecal samples of pigs/piglets suffering from diarrhea in Haryana, India with the help of next generation sequencing. The cDNA library was prepared from the faecal samples and run on the Illumina MiSeq instrument followed by identification and genomic characterization. Result: This study revealed the presence of SVA in the samples. The characterization of complete genome sequence of this strain showed complete nucleotide identity (100%) with SVA genomes reported from Canada, however, the polyprotein shares 98-99% amino acid sequence similarity with the genomes currently available in the GenBank. To the best of our knowledge this is the first report of SVA infection in pigs/piglets of Haryana, India. It demonstrates that an active and urgent surveillance of the swine population is required in the region. Additionally, the veterinarians must pay immediate attention to this vesicular disease and adopt preventive measures for its control.

Brucellosis Initially Misidentified as Ochrobactrum anthropi Bacteremia: A Case Report and Review of the Literature

Automated identification systems may misidentify Brucella, the causative agent of brucellosis, which may be re-emerging in the United States as the result of an expanding feral swine population. We present a case of Brucella suis likely associated with feral swine exposure that was misidentified as Ochrobactrum anthropi, a phylogenetic relative.

Diversity of the Swine Leukocyte Antigen Class I and II in Commercial Pig Populations

Among swine genetic markers, the highly polymorphic swine leukocyte antigen (SLA) is one of the key determinants, associated with not only immune responses but also reproductive performance and meat quality. The objective of this study was to characterize the SLA class I and II diversities in the commercial pig populations. In this study, a total number of 158 pigs (126 gilts and 32 boars) were randomly selected from different breeding herds of five major pig-producing companies, which covered ~70% of Thai swine production. The results indicate that a moderate level of SLA diversity was maintained in the Thai swine population, despite the performance-oriented breeding scheme. The highly common SLA class I alleles were SLA-1*08:XX, SLA-2*02:XX, and SLA-3*04:XX at a combined frequency of 30.1, 18.4, and 34.5%, respectively, whereas DRB1*04:XX, DQB1*02:XX and DQA*02:XX were the common class II alleles at 22.8, 33.3, and 38.6%, respectively. The haplotype Lr-32.0 (SLA-1*07:XX, SLA-2*02:XX, and SLA-3*04:XX) and Lr-0.23 (DRB1*10:XX, DQB1*06:XX, DQA* 01:XX) was the most common SLA class I and II haplotype, at 15.5 and 14.6%, respectively. Common class I and II haplotypes were also observed, which Lr-22.15 was the most predominant at 11.1%, followed by Lr-32.12 and Lr-4.2 at 10.8 and 7.9%, respectively. To our knowledge, this is the first report of SLA class I and II diversities in the commercial pigs in Southeast Asia. The information of the common SLA allele(s) in the population could facilitate swine genetic improvement and future vaccine design.

Porcine Gammaherpesviruses in Italian Commercial Swine Population: Frequent but Harmless

Differently from alpha- and betaherpesviruses affecting swine, interest in the recently discovered Suid gammaherpesvirus 3, Suid gammaherpesvirus 4, and Suid gammaherpesvirus 5, also known as porcine lymphotropic herpesviruses (PLHV-1, PLHV-2, and PLHV-3), has largely focused on their role as potential zoonotic agents in cases of xenotransplantation. However, their role as primary pathogens of swine or as co-factors for other lymphotropic infections has essentially been neglected. The present study aims at filling this gap, evaluating the association between PLHVs infection and different clinical conditions and/or porcine circovirus (PCV) co-infection. One hundred seventy-six samples were obtained from different animals located in a high-density pig area of Northern Italy in the period 2017–2020. The presence of PLHVs and PCVs was tested and quantified by specific real-time PCR: PLHVs were widespread among pigs (PLHV-1, PLHV-2, and PLHV-3 prevalence was 28.97%, 10.79%, and 4.54%, respectively) and detected in all considered tissues and clinical conditions. Frequent co-infections were also observed among PLHVs and with PCVs, although a significant association was not detected with the exception of a positive interaction between PLHV-1 and PLHV-3, and a negative one between PLHV-2 and PCV-2. Significantly, no association between PLHVs, alone or in co-infection, emerged with any of the considered clinical signs, their frequency being comparable between healthy and diseased animals. Based on these pieces of evidence and despite their high prevalence, PLHVs’ relevance for the swine industry appears negligible, either as primary pathogens or as predisposing factors for circovirus-induced diseases.

Silver nanoparticles in disinfection

Infectious diseases, now especially African swine fever (ASF), represent a major challenge for swine production in Central and Eastern Europe. In the absence of other methods, biosecurity plays the most important role in control of infectious diseases in swine population. Among biosecurity methods, disinfection proved to be one of the most effective and economically viable tools. Nanotechnology is an important, rapidly evolving multidisciplinary field. Achievements of nanotechnology are being used in many areas of science, such as biology, chemistry, physics, etc. Nanoproducts have been widely adopted for practical use in everyday life. For example, silver nanoparticles (AgNPs), thanks to their intrinsic antipathogenic properties and their ability to inactivate bacteria, viruses and fungi either photothermally or by photo catalysis (induced reactive oxygen generation), can offer methods alternative to classical disinfection protocols. It has been proved, both under laboratory conditions and in field veterinary practice, that AgNPs are very useful and efficient as a disinfectant of farm facilities.

Genetic Determinants of Resistance to Extended-Spectrum Cephalosporin and Fluoroquinolone in Escherichia coli Isolated from Diseased Pigs in the United States

ABSTRACT Fluoroquinolones and cephalosporins are critically important antimicrobial classes for both human and veterinary medicine. We previously found a drastic increase in enrofloxacin resistance in clinical Escherichia coli isolates collected from diseased pigs from the United States over 10 years (2006 to 2016). However, the genetic determinants responsible for this increase have yet to be determined. The aim of the present study was to identify and characterize the genetic basis of resistance against fluoroquinolones (enrofloxacin) and extended-spectrum cephalosporins (ceftiofur) in swine E. coli isolates using whole-genome sequencing (WGS). blaCMY-2 (carried by IncA/C2, IncI1, and IncI2 plasmids), blaCTX-M (carried by IncF, IncHI2, and IncN plasmids), and blaSHV-12 (carried by IncHI2 plasmids) genes were present in 87 (82.1%), 19 (17.9%), and 3 (2.83%) of the 106 ceftiofur-resistant isolates, respectively. Of the 110 enrofloxacin-resistant isolates, 90 (81.8%) had chromosomal mutations in gyrA, gyrB, parA, and parC genes. Plasmid-mediated quinolone resistance genes [qnrB77, qnrB2, qnrS1, qnrS2, and aac-(6)-lb′-cr] borne on ColE, IncQ2, IncN, IncF, and IncHI2 plasmids were present in 24 (21.8%) of the enrofloxacin-resistant isolates. Virulent IncF plasmids present in swine E. coli isolates were highly similar to epidemic plasmids identified globally. High-risk E. coli clones, such as ST744, ST457, ST131, ST69, ST10, ST73, ST410, ST12, ST127, ST167, ST58, ST88, ST617, ST23, etc., were also found in the U.S. swine population. Additionally, the colistin resistance gene (mcr-9) was present in several isolates. This study adds valuable information regarding resistance to critical antimicrobials with implications for both animal and human health. IMPORTANCE Understanding the genetic mechanisms conferring resistance is critical to design informed control and preventive measures, particularly when involving critically important antimicrobial classes such as extended-spectrum cephalosporins and fluoroquinolones. The genetic determinants of extended-spectrum cephalosporin and fluoroquinolone resistance were highly diverse, with multiple plasmids, insertion sequences, and genes playing key roles in mediating resistance in swine Escherichia coli. Plasmids assembled in this study are known to be disseminated globally in both human and animal populations and environmental samples, and E. coli in pigs might be part of a global reservoir of key antimicrobial resistance (AMR) elements. Virulent plasmids found in this study have been shown to confer fitness advantages to pathogenic E. coli strains. The presence of international, high-risk zoonotic clones provides worrisome evidence that resistance in swine isolates may have indirect public health implications, and the swine population as a reservoir for these high-risk clones should be continuously monitored.