Prevalence of enteric pathogens in diarrheic and non-diarrheic samples from pig farms with neonatal diarrhea in the North East of Spain

Diarrhea is one of the major causes of neonatal mortality in pigs. In the present study, 31 pig farms with outbreaks of neonatal diarrhea were investigated in Catalonia (NE Spain) from February 2017 until June 2018. Two hundred and fifteen diarrheic samples from 1 to 7 days old piglets were tested for a panel of enteric pathogens. In 19 of the studied farms additional fecal samples from apparently healthy pen-mates were collected and tested for the same panel of infectious agents. Samples were bacteriologically cultured and tested by PCR for E. coli virulence factors genes, C. perfringens types A and C toxins (Cpα, Cpβ, Cpβ2) and C. difficile toxins (TcdA, TcdB). Moreover, Rotavirus A (RVA), Rotavirus B (RVB), Rotavirus C (RVC), porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) were also determined by RT-qPCR. More than one pathogen could be detected in all of the outbreaks. Nevertheless, RVA was the only agent that could be statistically correlated with the outcome of diarrhea. For the other viruses and bacteria analyzed significant differences between the diseased pigs and the controls were not found. In spite of this, the individual analysis of each of the studied farms indicated that other agents such as RVB, RVC, toxigenic C. difficile or pathogenic E. coli could play a relevant role in the outbreak of diarrhea. In conclusion, the large diversity of agent combinations and disease situations detected in neonatal diarrhea outbreaks of this study stand for a more personalized diagnosis and management advice at a farm level.info:eu-repo/semantics/acceptedVersio

Analysis of ORF5 and Full-Length Genome Sequences of Porcine Reproductive and Respiratory Syndrome Virus Isolates of Genotypes 1 and 2 Retrieved Worldwide Provides Evidence that Recombination Is a Common Phenomenon and May Produce Mosaic Isolates

Recombination is currently recognized as a factor for high genetic diversity, but the frequency of such recombination events and the genome segments involved are not well known. In the present study, we initially focused on the detection of recombinant porcine reproductive and respiratory syndrome virus (PRRSV) isolates by examining previously published data sets of ORF5 sequences (genotypes 1 and 2) obtained worldwide. We then examined full-length genome sequences in order to determine potential recombination breakpoints along the viral genome. For ORF5, 11 sets of genotype 1 sequences from different geographical areas, including 2 Asian, 1 American, and 7 European regions, and three sets of genotype 2, including sets from China, Mexico, and the United States, were analyzed separately. Potential recombination breakpoints were detected in 10/11 genotype 1 sets, including 9 cases in which the clustering of at least one isolate was different before and after the breakpoints. In genotype 2, potential breakpoints and different tree clustering of at least one strain before and after the breakpoint were observed in 2 out of 3 sets. The results indicated that most of the ORF5 data sets contained at least one recombinant sequence. When the full-length genome sequences were examined, both genotype 1 and 2 sets presented breakpoints (10 and 9, respectively), resulting in significantly different topologies before and after the breakpoints. Mosaic genomes were detected in genotype 1 sequences. These results may have significant implications for the understanding of the molecular epidemiology of PRRSV. IMPORTANCE PRRSV is one of the most important viruses affecting swine production worldwide, causing big economic losses and sanitary problems. One of the key questions on PRRSV arises from its genetic diversity, which is thought to have a direct impact on immunobiology, epidemiology, diagnosis, and vaccine efficacy. One of the causes of this genetic diversity is recombination among strains. This study provides evidence that recombinant PRRSV isolates are common in most of the countries with significant swine production, especially PRRSV genotype 1. This observation has implications in the proper characterization of PRRSV strains, in the future development of phylogenetic studies, and in the development of new PRRSV control strategies. Moreover, the present paper emphasizes the need for a deeper understanding of the mechanisms and circumstances involved in the generation of genetic diversity of PRRSV

A pilot RNA-seq study in 40 pietrain ejaculates to characterize the porcine sperm microbiome

The microbiome plays a key role in homeostasis and health and it has been also linked to fertility and semen quality in several animal species including swine. Despite the more than likely importance of sperm bacteria on the boar's reproductive ability and the dissemination of pathogens and antimicrobial resistance genes, the high throughput characterization of the swine sperm microbiome remains scarce. We carried RNA-seq on 40 ejaculates each from a different Pietrain boar and found that a proportion of the sequencing reads did not map to the Sus scrofa genome. The current study aimed at using these reads not belonging to pig to carry a pilot study to profile the boar sperm bacterial population and its relation with 7 semen quality traits. We found that the boar sperm contains a broad population of bacteria. The most abundant phyla were Proteobacteria (39.1%), Firmicutes (27.5%), Actinobacteria (14.9%) and Bacteroidetes (5.7%). The predominant species contaminated sperm after ejaculation from soil, faeces and water sources (Bacillus megaterium, Brachybacterium faecium, Bacillus coagulans). Some potential pathogens were also found but at relatively low levels (Escherichia coli, Clostridioides difficile, Clostridium perfringens, Clostridium botulinum and Mycobacterium tuberculosis). We also identified 3 potential antibiotic resistant genes from E. coli against chloramphenicol, Neisseria meningitidis against spectinomycin and Staphylococcus aureus against linezolid. None of these genes were highly abundant. Finally, we classified the ejaculates into categories according to their bacterial features and semen quality parameters and identified two categories that significantly differed for 5 semen quality traits and 13 bacterial features including the genera Acinetobacter, Stenotrophomonas and Rhodobacter. Our results show that boar semen contains a bacterial community, including potential pathogens and putative antibiotic resistance genes, and that these bacteria may affect its reproductive performance.info:eu-repo/semantics/acceptedVersio

Antimicrobial susceptibility profiles of Salmonella strains isolated from pigs in Spain

This study deals with the antimicrobial susceptibility profiles of Salmonella strains isolated from healthy or diseased pigs in Spain. Salmonella Typhimurium was the most frequent serotype (46/139) being the phagetype DTI04b the commonest among them. Strains belonging to the serotype 4,5,12:i:- (also called monophasic strains) were often isolated (23/139). A great proportion of them (13/23) were characterised as phagetype U302. Other frequent serotypes were Anatum (17/139), Tilburg (13/139) and Virchow (7/139). Antimicrobial susceptibility tests showed that most strains were resistant to tetracycline (T) 82%, sulphonamides (Su) 81%, ampicillin (A) 74%, chloramphenicol (C) 58% and trimethoprim (Tm) 53%. Regarding the determination of minimal inhibitory concentration (MIC) for enrofloxacin, 4/139 strains were resistant( 4Jlg/ml) while 37 showed decreased susceptibility (~0.5J.1glml). The most common pattern of antibiotic resistance was ACSuTTm, found predominantly in serotype Typhimurium and in monophasic strains

Photopolymerized micelles of diacetylene amphiphile: physical characterization and cell delivery properties:

A series of polydiacetylene (PDA) - based micelles were prepared from diacetylenic surfactant bearing polyethylene glycol, by increasing UV-irradiation times. These polymeric lipid micelles were analyzed by physicochemical methods, electron microscopy and NMR analysis. Cellular delivery of fluorescent dye suggests that adjusting the polymerization state is vital to reach the full in vitro potential of PDA-based delivery system

On the rotational evolution of solar- and late-type stars, its magnetic origins, and the possibility of stellar gyrochronology

We propose a simple interpretation of the rotation period data for solar- and late-type stars. The open cluster and Mt. Wilson star observations suggest that rotating stars lie primarily on two sequences, initially called I and C. Some stars lie in the intervening gap. These sequences, and the fractional numbers of stars on each sequence evolve systematically with cluster age, enabling us to construct crude rotational isochrones allowing `stellar gyrochronology', a procedure, upon improvement, likely to yield ages for individual field stars. The age and color dependences of the sequences allow the identification of the underlying mechanism, which appears to be primarily magnetic. The majority of solar- and late-type stars possess a dominant Sun-like, or Interface magnetic field, which connects the convective envelope both to the radiative interior of the star and to the exterior where winds can drain off angular momentum. These stars spin down Skumanich-style. An age-decreasing fraction of young G, K, and M stars, which are rapid rotators, possess only a Convective field which is not only inefficient in depleting angular momentum, but also incapable of coupling the surface convection zone to the inner radiative zone, so that only the outer zone is spun down, and on an exponential timescale. These stars do not yet possess large-scale dynamos. The large-scale magnetic field associated with the dynamo, apparently created by the shear between the decoupled radiative and convective zones, (re)couples the convective and radiative zones and drives a star from the Convective to the Interface sequence through the gap on a timescale that increases as stellar mass decreases. (Abstract is truncated here.)Comment: 32 pages, 6 figures (4 in color), accepted by Ap

Hydrophilic microporous membranes for selective ion separation and flow-battery energy storage

Membranes with fast and selective ion transport are widely used for water purification and devices for energy conversion and storage including fuel cells, redox flow batteries and electrochemical reactors. However, it remains challenging to design cost-effective, easily processed ion-conductive membranes with well-defined pore architectures. Here, we report a new approach to designing membranes with narrow molecular-sized channels and hydrophilic functionality that enable fast transport of salt ions and high size-exclusion selectivity towards small organic molecules. These membranes, based on polymers of intrinsic microporosity containing Tröger’s base or amidoxime groups, demonstrate that exquisite control over subnanometre pore structure, the introduction of hydrophilic functional groups and thickness control all play important roles in achieving fast ion transport combined with high molecular selectivity. These membranes enable aqueous organic flow batteries with high energy efficiency and high capacity retention, suggesting their utility for a variety of energy-related devices and water purification processes

Chemical Abundances and Rotation Velocities of Blue Horizontal-Branch Stars in Six Globular Clusters

High-resolution spectroscopic measurements of blue horizontal-branch stars in six metal-poor globular clusters -- M3, M13, M15, M68, M92, and NGC 288 -- reveal remarkable variations in photospheric composition and rotation velocity as a function of a star's position along the horizontal branch. For the cooler stars (Teff < 11200 K), the derived abundances are in good agreement with the canonical cluster metallicities, and we find a wide range of v sin i rotation velocities, some as high as 40 km/s. In the hotter stars, however, most metal species are strongly enhanced, by as much as 3 dex, relative to the expected cluster metallicity, while helium is depleted by 2 dex or more. In addition, the hot stars all rotate slowly, with v sin i < 8 km/s. The anomalous abundances appear to be due to atomic diffusion mechanisms -- gravitational settling of helium, and radiative levitation of metals -- in the non-convective atmospheres of these hot stars. We discuss the influence of these photospheric metal enhancements on the stars' photometric properties, and explore possible explanations for the observed distribution of rotation velocities.Comment: 77 pages, 27 figures, accepted for November 2003 publication in ApJ

Genetic and antigenic characterization of complete genomes of Type 1 Porcine Reproductive and Respiratory Syndrome viruses (PRRSV) isolated in Denmark over a period of 10 years

AbstractPorcine Reproductive and Respiratory Syndrome (PRRS) caused by the PRRS virus (PRRSV) is considered one of the most devastating swine diseases worldwide. PRRS viruses are divided into two major genotypes, Type 1 and Type 2, with pronounced diversity between and within the genotypes. In Denmark more than 50% of the herds are infected with Type 1 and/or Type 2 PRRSV. The main objective of this study was to examine the genetic diversity and drift of Type 1 viruses in a population with limited introduction of new animals and semen. A total of 43 ORF5 and 42 ORF7 nucleotide sequences were obtained from viruses collected from 2003 to February 2013. Phylogenetic analysis of ORF5 nucleotide sequences showed that the Danish isolates formed two major clusters within the subtype 1. The nucleotide identity to the subtype 1 protogenotype Lelystad virus (LV) spanned 84.9–98.8% for ORF5 and 90.7–100% for ORF7. Among the Danish viruses the pairwise nucleotide identities in ORF5 and ORF7 were 81.2–100% and 88.9–100%, respectively. Sequencing of the complete genomes, including the 5′- and 3′-end nucleotides, of 8 Danish PRRSV Type 1 showed that the genome lengths differed from 14,876 to 15,098 nucleotides and the pairwise nucleotide identity among the Danish viruses was 86.5–97.3% and the identity to LV was 88.7–97.9%. The study strongly indicated that there have been at least two independent introductions of Type 1 PRRSV in Denmark and analysis of the full genomes revealed a significant drift in several regions of the virus

Comparative analysis of the impact of geological activity on astronomical sites of the Canary Islands, Hawaii and Chile

An analysis of the impact of seismic and volcanic activity was carried out at selected astronomical sites, namely the observatories of El Teide (Tenerife, Canary Islands), Roque de los Muchachos (La Palma, Canary Islands), Mauna Kea (Hawaii) and Paranal (Chile) and the candidate site of Cerro Ventarrones (Chile). Hazard associated to volcanic activity is low or negligible at all sites, whereas seismic hazard is very high in Chile and Hawaii. The lowest geological hazard in both seismic and volcanic activity was found at Roque de los Muchachos observatory, in the island of La Palma.Comment: 12 pages and 11 figure