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Rotaviruses (RVs) are classified into nine species or groups (RVA-RVD and RVF-RVJ). RVA, RVB and RVC are well-recognized as etiological agents of enteric disease on swine farms and have been identified in all countries with a relevant pork production. Contrarily, RVH has only been identified on swine farms from Japan and more recently from Brazil, USA, South Africa and Vietnam but not yet in Europe. The occurrence of RVH was investigated in 103 Spanish pig herds. Nine farms were positive and we achieved a complete nucleotide sequences in three isolates while another RVH isolate was partially sequenced. Mean nucleotide identities with the RVH sequences available in GenBank ranged between 69.4 and 93.7 %. Phylogenetically, all genomic segments of Spanish RVH isolates clustered closely with other porcine RVH strains but were distantly related to human RVH as well as bat RVH strain. To the best of our knowledge this is the first report of RVH on swine farms in Europe including its characterization by means of complete genome sequencing. info:eu-repo/semantics/acceptedVersion

Rotaviruses (RVs) are a major cause of viral gastroenteritis in both animals and humans worldwide. According to the molecular and serological properties of Viral Protein 6 (VP6), RVs are classified into nine species or groups (RVA-RVD and RVF-RVJ). RVA, RVB and RVC are well-recognized as etiological agents of enteric disease on swine farms and have been identified in all countries with a relevant pork production. Contrarily, RVH has only been identified on swine farms from Japan and more recently from Brazil, USA, South Africa and Vietnam but not yet in Europe. The occurrence of RVH was investigated in 103 Spanish pig herds. Nine farms were positive and the complete nucleotide sequences were achieved for four RVH isolates. Mean nucleotide identities with the RVH sequences available in GenBak ranged between 69.4 and 93.7 %. Phylogenetically, all genomic segments of Spanish RVH isolates clustered closely with other porcine RVH strains but were distantly related to human RVH as well as bat RVH strain. Moreover, based on the available tentative genotyping system for RVH, a new genotype for VP7 was proposed. To the best of our knowledge this is the first report of RVH on swine farms in Europe including its characterization by means of complete genome sequencing.

Background Diarrhoea is a major cause of death in neonate pigs and most of the viruses that cause it are RNA viruses. Next Generation Sequencing (NGS) deeply characterize the genetic diversity among rapidly mutating virus populations at the interspecific as well as the intraspecific level. The diversity of RNA viruses present in faeces of neonatal piglets suffering from diarrhoea in 47 farms, plus 4 samples from non-diarrhoeic piglets has been evaluated by NGS. Samples were selected among the cases submitted to the Veterinary Diagnostic Laboratories of Infectious Diseases of the Universitat Autònoma de Barcelona (Barcelona, Spain) and Universidad de León (León, Spain). Results The analyses identified the presence of 12 virus species corresponding to 8 genera of RNA viruses. Most samples were co-infected by several viruses. Kobuvirus and Rotavirus were more commonly reported, with Sapovirus, Astrovirus 3, 4 and 5, Enterovirus G, Porcine epidemic diarrhoea virus, Pasivirus and Posavirus being less frequently detected. Most sequences showed a low identity with the sequences deposited in GenBank, allowing us to propose several new VP4 and VP7 genotypes for Rotavirus B and Rotavirus C. Conclusions Among the cases analysed, Rotaviruses were the main aetiological agents of diarrhoea in neonate pigs. Besides, in a small number of cases Kobuvirus and Sapovirus may also have an aetiological role. Even most animals were co-infected in early life, the association with enteric disease among the other examined viruses was unclear. The NGS method applied successfully characterized the RNA virome present in faeces and detected a high level of unreported intraspecific diversity.

Background Accurate screening of new alternative antimicrobial compounds is essential for their use to control pathogens in swine production due to the replacement of antibiotics and zinc oxide. Most in vitro studies have separately reported the antimicrobial activity of organic acids and essential oils (EOs) using diverse methods for susceptibility testing. In addition, in vitro outcomes can help in the selection of the suitable antimicrobial compound and effective combinations of these compounds in the control of pathogens of interest in pork production. Therefore, the aim of this study is to determinate the antibacterial activity of six organic acids and six EOs against Escherichia coli, Salmonella spp. and Clostridium perfringens isolates, some of them multi-resistant to antibiotics, from swine origin. The synergistic effects between the products with higher activity for each bacteria were also calculated. Results All products tested showed activity against at least one bacterial species, except for black pepper EO. The results showed that formic acid with the shortest chain length was the most effective against E. coli and Salmonella spp., while the sodium salt of coconut fatty acid distillates with long chain acids was the most effective against C. perfringens. The susceptibility of isolates tested to EOs was similar, a result that demonstrates a similar activity of these products against phylogenetically unrelated pathogens. In addition, an additive effect was shown for carvacrol-oregano EO for E. coli, formic acid-carvacrol and formic acid-thymol for Salmonella spp. and carvacrol-cinamaldehyde for C. perfringens. Conclusions The susceptibility of isolates to EOs was similar, a result that demonstrates a similar activity of these products against phylogenetically unrelated pathogens in contrast to organic acids. In addition, an additive effect was shown for several combinations of these compounds.

Brachyspira hyodysenteriae is the main etiological agent of swine dysentery (SD). Nowadays, treatment and control of SD is increasingly difficult due to the emergence of antimicrobial resistance together with the restrictions on the use of antibiotics in veterinary practice. The aim of this study was to evaluate, as an alternative in the control of this disease, the antimicrobial activity and the main mechanism of action of BIOCITRO, a citrus extract commercialized as raw material and used as feed additive, against B. hyodysenteriae. Ten isolates of B. hyodysenteriae were used to assess the minimum inhibitory and minimum bactericidal concentrations (MIC and MBC) of BIOCITRO by broth microdilution method. Moreover, stationary phase cultures of two B. hyodysenteriae strains were subjected for 90min to four different concentrations of BIOCITRO and compared with the untreated controls by flow cytometry (FC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results showed that BIOCITRO has a relevant bacteriostatic and bactericidal effect against B. hyodysenteriae with MIC and MBC values ranging from 32 to 128partspermillion (ppm). It induces damage in at least 35% and 76% of the bacterial cells when exposed to 128 and 256ppm of BIOCITRO respectively as revealed by the intake of propidium iodide by FC. Relevant changes in the structure of the bacterial cells were observed by SEM and confirmed by FTIR. According to these results, BIOCITRO seems to be a satisfactory alternative to the use of antibiotics in the control of SD.

The Pleistocene climatic oscillations promoted the diversification in avian species during the last glacial period. The red-legged partridge (Alectoris rufa, Family Phasianidae) has a large natural distribution extending from the Mediterranean to humid temperate zones. However, the genetic structure for this species is unknown. The present study investigates the phylogeography, genetic structure and demographic history of A. rufa across its distribution, employing both mitochondrial DNA control region sequences and nuclear microsatellite loci. Our results propose that this species was greatly affected by Pleistocene glaciations. The mismatch analyses suggest that the current populations resulted from post-glacial expansion and subsequent differentiation resulting in five diagnosable genetic clusters: Southwestern, Central-eastern, Northwestern, Balearic and French and Italian. Further, we found evidence of three glacial refugia within the currently recognized Iberian glacial refugium. The intraspecific structure revealed by both maternal and biparental phylogeographic analyses was not resolved in the phylogenetic analyses. Based on all considerations, we recommended that five management units be recognized.

Porcine epidemic diarrhea (PED) is an enteric disease in swine caused by an alphacoronavirus. It affects swine of all ages causing acute diarrhoea and can lead to severe dehydration and death in suckling piglets. Being recognized for the first time in Europe and Asia during the seventies and the eighties, respectively, it has remained a relevant cause of diarrhea outbreaks in Asia for years and to the present. It has become a major concern in swine production since 2013 when the virus was detected for first time in the USA and in other American countries causing a high number of pig deaths and significant economic losses. The present review aims at approaching the reader to the state of the art of PED giving answer to some of the most recent questions which have arisen related to this disease.

The Pleistocene climatic oscillations promoted the diversification in avian species during the last glacial period. The red-legged partridge (Alectoris rufa, Family Phasianidae) has a large natural distribution extending from the Mediterranean to humid temperate zones. However, the genetic structure for this species is unknown. The present study investigates the phylogeography, genetic structure and demographic history of A. rufa across its distribution, employing both mitochondrial DNA control region sequences and nuclear microsatellite loci. Our results propose that this species was greatly affected by Pleistocene glaciations. The mismatch analyses suggest that the current populations resulted from post-glacial expansion and subsequent differentiation resulting in five diagnosable genetic clusters: Southwestern, Central-eastern, Northwestern, Balearic and French and Italian. Further, we found evidence of three glacial refugia within the currently recognized Iberian glacial refugium. The intraspecific structure revealed by both maternal and biparental phylogeographic analyses was not resolved in the phylogenetic analyses. Based on all considerations, we recommended that five management units be recognized.

In the last few years the presence in thylakoid membranes of chloroplasts of a NAD(P)H-plastoquinone oxidoreductase complex (Ndh complex) homologous to mitochondrial complex I has been well established. Herein, we report the identification of the Ndh complex in barley etioplast membranes. Two plastid DNA-encoded poly peptides of the Ndh complex (NDH-A and NDH-F) were relatively more abundant in etioplast membranes than in thylakoids from greening chloroplasts. Conversion of etioplast into chloroplast, after light exposure of barley seedlings grown in the dark, was accompanied by a decrease in the NADH dehydrogenase activity associated to plastid membranes. Using native-PAGE and immunolabelling techniques we have determined that a NADH specific dehydrogenase activity associated with plastid membranes, which was more active in etioplasts than in greening chloroplasts, contained the NDH-A and NDH-F polypeptides. These results complemented by those obtained through blue-native-PAGE indicated that NDH-A and NDH-F polypeptides are part of a 580 kDa NADH dependent dehydrogenase complex present in etioplast membranes. This finding proves that accumulation of the Ndh complex is independent of light. The decrease in the relative levels and specific activity of this complex during the transition from etioplast to chloroplasts was accompanied by a parallel decrease in the specific activity of peroxidase associated to plastid membranes. Based on the mentioned observations it is proposed that an electron transport chain from NADH to H 2O2 could be active in barley etioplasts.