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Frontiers in Veterinary Science 2022A few decades ago, porcine respiratory disease complex (PRDC) exerted a major economic impact on the global swine industry, particularly due to the adoption of intensive... (Review)
Review
A few decades ago, porcine respiratory disease complex (PRDC) exerted a major economic impact on the global swine industry, particularly due to the adoption of intensive farming by the latter during the 1980's. Since then, the emerging of porcine reproductive and respiratory syndrome virus (PRRSV) and of porcine circovirus type 2 (PCV2) as major immunosuppressive viruses led to an interaction with other endemic pathogens (e.g., .) in swine farms, thereby exacerbating the endemic clinical diseases. We herein, review and discuss various dynamic polymicrobial infections among selected swine pathogens. Traditional biosecurity management strategies through multisite production, parity segregation, batch production, the adoption of all-in all-out production systems, specific vaccination and medication protocols for the prevention and control (or even eradication) of swine diseases are also recommended. After the introduction of the African swine fever (ASF), particularly in Asian countries, new normal management strategies minimizing pig contact by employing automatic feeding systems, artificial intelligence, and robotic farming and reducing the numbers of vaccines are suggested. Re-emergence of existing swine pathogens such as PRRSV or PCV2, or elimination of some pathogens may occur after the ASF-induced depopulation. ASF-associated repopulating strategies are, therefore, essential for the establishment of food security. The "repopulate swine farm" policy and the strict biosecurity management (without the use of ASF vaccines) are, herein, discussed for the sustainable management of small-to-medium pig farms, as these happen to be the most potential sources of an ASF re-occurrence. Finally, the ASF disruption has caused the swine industry to rapidly transform itself. Artificial intelligence and smart farming have gained tremendous attention as promising tools capable of resolving challenges in intensive swine farming and enhancing the farms' productivity and efficiency without compromising the strict biosecurity required during the ongoing ASF era.
PubMed: 36504860
DOI: 10.3389/fvets.2022.1048861 -
Veterinary Record Open Dec 2022The Gram-negative bacterium is an agent of global importance to the swine industry and the cause of lethal respiratory or septicaemic disease in pigs of different ages....
OBJECTIVE
The Gram-negative bacterium is an agent of global importance to the swine industry and the cause of lethal respiratory or septicaemic disease in pigs of different ages. Between 2018 and 2019, seven commercial farms in western Canada experienced episodes of increased mortality due to infection in grower pigs. The goal of this work was to profile, with molecular methods, isolated from diseased pigs and to compare them to other isolates.
DESIGN
This inferential observational study used nine western Canadian strains obtained from diseased lungs ( = 6), heart ( = 2) and brain ( = 1) and whole genome sequencing was performed. Comparative genomic analyses were performed to characterise the genetic variability, antimicrobial resistance and the virulence genes present.
RESULTS
Compared to the reference strain (ATCC 33415), an increased number of RTX (repeats in the structural toxin) gene copies were identified in strains isolated from organs without a mucosal surface, thus theoretically harder to invade. Western Canadian strains did not harbour genes associated with resistance to antimicrobial agents used in swine production. Novel regions were also identified in the genomes of five of nine strains demonstrating recombination and emergence of novel strains.
CONCLUSIONS
The results obtained in this study were associated with the emergence of new lineages. An increased number of RTX toxin gene copies is suggested to be associated with increased virulence. This study will contribute to improve our understanding regarding and may help guide vaccine development and agent control measures.
PubMed: 36213600
DOI: 10.1002/vro2.45 -
International Journal of Molecular... Aug 2022(, Gram negative) and (.) (Gram positive) can cause severe diseases in pigs. During infection, neutrophils infiltrate to counteract these pathogens with phagocytosis...
(, Gram negative) and (.) (Gram positive) can cause severe diseases in pigs. During infection, neutrophils infiltrate to counteract these pathogens with phagocytosis and/or neutrophil extracellular traps (NETs). NETs consist of a DNA-backbone spiked with antimicrobial components. The NET formation mechanisms in porcine neutrophils as a response to both of the pathogens are not entirely clear. The aim of this study was to investigate whether (serotype 2, C3656/0271/11) and (serotype 2, strain 10) induce NETs by NADPH oxidase- or CD18-dependent mechanisms and to characterize phenotypes of NETs in porcine neutrophils. Therefore, we investigated NET induction in porcine neutrophils in the presence and absence of NET inhibitors and quantified NETs after 3 h. Furthermore, NETosis and phagocytosis were investigated by transmission electron microscopy after 30 min to characterize different phenotypes. and induce NETs that are mainly ROS-dependent. induces NETs that are partially CD18-dependent. Thirty minutes after infection, both of the pathogens induced a vesicular NET formation with only slight differences. Interestingly, some neutrophils showed only NET-marker positive phagolysosomes, but no NET-marker positive vesicles. Other neutrophils showed vesicular NETs and only NET-marker negative phagolysosomes. In conclusion, both of the pathogens induce ROS-dependent NETs. Vesicular NETosis and phagocytosis occur in parallel in porcine neutrophils in response to serotype 2 and serotype 2.
Topics: Animals; Bacterial Infections; Extracellular Traps; Neutrophils; Reactive Oxygen Species; Streptococcus suis; Swine
PubMed: 36012224
DOI: 10.3390/ijms23168953 -
Frontiers in Cellular and Infection... 2022Respiratory infections seriously affect the swine industry worldwide. Co-infections of two vital pathogenic bacteria () and (), colonizing the respiratory tract often...
Respiratory infections seriously affect the swine industry worldwide. Co-infections of two vital pathogenic bacteria () and (), colonizing the respiratory tract often occurs in veterinary clinical practice. Moreover, our previous research found that and can form biofilm . The formation of a mixed biofilm not only causes persistent infections, but also increases the multiple drug resistance of bacteria, which brings difficulties to disease prevention and control. However, the methods for detecting and in co-infection and biofilm are immature. Therefore, in this study, primers and probes were designed based on the conservative sequence of gene and IVA gene. Then, a TaqMan duplex real-time PCR method for simultaneous detection of and was successfully established optimizing the reaction system and conditions. The specificity analysis results showed that this TaqMan real-time PCR method had strong specificity and high reliability. The sensitivity test results showed that the minimum detection concentration of and recombinant plasmid was 10 copies/μL, which is 100 times more sensitive than conventional PCR methods. The amplification efficiencies of and were 95.9% and 104.4% with R value greater than 0.995, respectively. The slopes of the calibration curves of absolute cell abundance of and were 1.02 and 1.09, respectively. The assays were applied to cultivated mixed biofilms and approximately 10 CFUs per biofilm were quantified when 10 CFUs planktonic bacteria of either or were added to biofilms. In summary, this study developed a TaqMan real-time PCR assay for specific, accurate quantification of or in mixed biofilms, which may help for the detection, prevention and control of diseases caused by a bacterial mixed infection involving and .
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Biofilms; Coinfection; Reproducibility of Results; Streptococcus suis; Swine; Swine Diseases
PubMed: 35992166
DOI: 10.3389/fcimb.2022.898412 -
Antibiotics (Basel, Switzerland) May 2022Antimicrobial susceptibility testing is necessary to carry out antimicrobial stewardship but a limited number of drugs belonging to each antimicrobial family has to be...
Antimicrobial susceptibility testing is necessary to carry out antimicrobial stewardship but a limited number of drugs belonging to each antimicrobial family has to be tested for technical limitations and economic resources. In this study, we have determined the minimal inhibitory concentration, using microdilution following international standards (CLSI), for 490 Actinobacillus pleuropneumoniae, 285 Pasteurella multocida, 73 Bordetella bronchiseptica, 398 Streptococcus suis and 1571 Escherichia coli strains from clinical cases collected in Spain between 2018 and 2020. The antimicrobial susceptibility pattern was deciphered using a principal component analysis for each bacterium and a matrix correlation (high > 0.8, medium 0.5−0.8 and low < 0.5) was obtained for each pair of antimicrobials. No significant associations were observed between MIC patterns for different antimicrobial families, suggesting that co-selection mechanisms are not generally present in these porcine pathogens. However, a high correlation was observed between the fluroquinolones (marbofloxacin and enrofloxacin) for all mentioned pathogens and for ceftiofur and cefquinome for E. coli and S. suis. Moreover, a significant association was also observed for tetracyclines (doxycycline and oxytetracycline) and B. bronchiseptica and tildipirosin/tulathromycin for P. multocida. These results suggest that generally, a representative drug per antimicrobial class cannot be selected, however, for some drug−bug combinations, MIC values from one representative drug could be extrapolated to the whole antimicrobial family.
PubMed: 35625283
DOI: 10.3390/antibiotics11050638 -
Frontiers in Genetics 2022The United Kingdom and European Union have banned crates for pregnant sows. However, animals are kept in a restrictive environment for up to four weeks after mating,...
The United Kingdom and European Union have banned crates for pregnant sows. However, animals are kept in a restrictive environment for up to four weeks after mating, leading to stress and different responses of the animals' immune system. Here, we used vaginal flushing of gilts to investigate whether housing systems or an experimental inflammatory challenge with lipopolysaccharide (LPS) can modify the gilt vaginal microbiome. Alpha-diversity indices showed differences in the microbiota of gilts housed under different systems ( = 0.04). Shannon alpha-diversity richness was higher in gilts group-housed in pens than in gilts housed in crates ( = 0.035), but not higher than in other groups. The relative abundance of the operational taxonomic unit (OTU) ( < 0.05) revealed specific differences in housing systems before a LPS or saline (SAL control) challenge. We found different abundances in taxa of , , , , and in gilts housed in the different systems before challenge. After the LPS challenge, significant differences were detected in the relative abundance of OTUs ( < 0.05) for the LPS-challenged group compared with SAL animals for each housing system. The phylum showed higher abundance among the LPS-challenged gilts than in SAL-challenged animals. Furthermore, was more abundant in the LPS-challenged gilts housed in crates than in SAL-challenged gilts housed in crates. and were more abundant in LPS-challenged gilts in indoor group housing than in SAL gilts in the same housing system. Gilts kept outdoors did not show changes in vaginal microbiota after an LPS challenge. Gilts housed in crates showed clinical signs of urogenital infection, whereas gilts housed outdoors and in indoor group housing did not. The relationship between environment, immune response, and microbiota suggested that animals in a poor environments experience difficulties responding to a challenge and their vaginal microbiota is altered as a consequence, with decreased richness of normal vaginal microbiota, and increased opportunistic bacteria. Welfare indicators measured by gilts' responses to housing systems however, do not fully explain mechanisms associated with the unique signature in vaginal microbiota encountered in the different housing systems.
PubMed: 35464863
DOI: 10.3389/fgene.2022.836962 -
The Journal of Veterinary Medical... May 2022The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely...
The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely isolated from ruminants. We describe here the isolation of A. suis sensu stricto from a newborn calf that died on a dairy farm in Japan. Identification of the isolate was performed by phenotypic and genotypic characterization, with the latter consisting of nucleotide sequence analyses of the 16S rRNA gene plus three housekeeping genes, rpoB, infB and recN.
Topics: Actinobacillus; Actinobacillus Infections; Actinobacillus suis; Animals; Phylogeny; RNA, Ribosomal, 16S; Swine; Swine Diseases
PubMed: 35387957
DOI: 10.1292/jvms.22-0044 -
Frontiers in Veterinary Science 2021() is one major bacterial porcine respiratory tract pathogen causing disease outbreaks worldwide, although effective commercial vaccines are available. Due to frequent...
Coinfections and Phenotypic Antimicrobial Resistance in Strains Isolated From Diseased Swine in North Western Germany-Temporal Patterns in Samples From Routine Laboratory Practice From 2006 to 2020.
() is one major bacterial porcine respiratory tract pathogen causing disease outbreaks worldwide, although effective commercial vaccines are available. Due to frequent failure of this preventive measure, treatment with antimicrobials is indispensable to prevent animal losses within an outbreak situation. To preserve the effectivity of antimicrobial substances to fight should therefore be the primary aim of any interventions. In this study, the temporal development of antimicrobial resistance in was analyzed retrospectively in the time period 2006-2020 from a routine diagnostic database. In parallel, frequent coinfections were evaluated to identify most important biotic cofactors as important triggers for disease outbreaks in endemically infected herds. The proportion of serotype 2 decreased over time but was isolated most often from diseased swine (57% in 2020). In ~1% of the cases, was isolated from body sites outside the respiratory tract as brain and joints. The lowest frequencies of resistant isolates were found for cephalothin and ceftiofur (0.18%), florfenicol (0.24%), tilmicosin (2.4%), tiamulin (2.4%), enrofloxacin (2.7%), and spectinomycin (3.6%), while the highest frequencies of resistant isolates were found for gentamicin (30.9%), penicillin (51.5%), and tetracycline (78.2%). For enrofloxacin, tiamulin, tilmicosin, and tetracycline, significantly lower frequencies of resistant isolates were found in the time period 2015-2020 compared to 2006-2014, while gentamicin-resistant isolates increased. In summary, there is only a low risk of treatment failure due to resistant isolates. In maximum, up to six coinfecting pathogens were identified in pigs positive for . Most often pigs were coinfected with Porcine Circovirus 2 (56%), (24.8%), or the Porcine Reproductive and Respiratory Syndrome Virus (23.3%). Potential synergistic effects between these pathogens published from experimental findings can be hypothesized by these field data as well. To prevent disease outbreaks in endemically infected herds more efficiently in the future, next to environmental trigger factors, preventive measures must also address the coinfecting agents.
PubMed: 35155648
DOI: 10.3389/fvets.2021.802570 -
The Journal of Antimicrobial... Feb 2022Building the European Antimicrobial Resistance Surveillance network in Veterinary medicine (EARS-Vet) was proposed to strengthen the European One Health antimicrobial...
BACKGROUND
Building the European Antimicrobial Resistance Surveillance network in Veterinary medicine (EARS-Vet) was proposed to strengthen the European One Health antimicrobial resistance (AMR) surveillance approach.
OBJECTIVES
To define the combinations of animal species/production types/age categories/bacterial species/specimens/antimicrobials to be monitored in EARS-Vet.
METHODS
The EARS-Vet scope was defined by consensus between 26 European experts. Decisions were guided by a survey of the combinations that are relevant and feasible to monitor in diseased animals in 13 European countries (bottom-up approach). Experts also considered the One Health approach and the need for EARS-Vet to complement existing European AMR monitoring systems coordinated by the ECDC and the European Food Safety Authority (EFSA).
RESULTS
EARS-Vet plans to monitor AMR in six animal species [cattle, swine, chickens (broilers and laying hens), turkeys, cats and dogs], for 11 bacterial species (Escherichia coli, Klebsiella pneumoniae, Mannheimia haemolytica, Pasteurella multocida, Actinobacillus pleuropneumoniae, Staphylococcus aureus, Staphylococcus pseudintermedius, Staphylococcus hyicus, Streptococcus uberis, Streptococcus dysgalactiae and Streptococcus suis). Relevant antimicrobials for their treatment were selected (e.g. tetracyclines) and complemented with antimicrobials of more specific public health interest (e.g. carbapenems). Molecular data detecting the presence of ESBLs, AmpC cephalosporinases and methicillin resistance shall be collected too.
CONCLUSIONS
A preliminary EARS-Vet scope was defined, with the potential to fill important AMR monitoring gaps in the animal sector in Europe. It should be reviewed and expanded as the epidemiology of AMR changes, more countries participate and national monitoring capacities improve.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Cats; Cattle; Chickens; Dogs; Drug Resistance, Bacterial; Female; One Health; Swine
PubMed: 35022739
DOI: 10.1093/jac/dkab462 -
EFSA Journal. European Food Safety... Dec 2021In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of pigs have been assessed. The...
In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of pigs have been assessed. The assessment has been performed following a methodology based on information collected by an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial resistant , , , , , , , , , , , , , , and has been provided. Among those bacteria, EFSA identified and with > 66% certainty as being the most relevant antimicrobial resistant bacteria in the EU based on the available evidence. The animal health impact of these most relevant bacteria, as well as their eligibility for being listed and categorised within the animal health law framework will be assessed in separate scientific opinions.
PubMed: 34987628
DOI: 10.2903/j.efsa.2021.7113