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Little is known about how co-infections and genotype dynamics affect Mycoplasma hyopneumoniae infection in fattening pigs. This study was aimed at assessing the role of co-infections in M. hyopneumoniae outbreaks, their influence on the presence of M. hyopneumoniae genotypes and their impact on consequent lung lesions. Tracheobronchial swabs (TBS) from 300 finishers were collected from 10 farms at the onset of enzootic pneumonia outbreaks and 1 month later, sampling of 3 groups per farm: Group A showed clinical signs first, Group B was housed near Group A, and Group C was located in a different building. Pigs’ lungs were scored at the slaughterhouse. TBS were tested for the main pathogens involved in respiratory diseases, and samples positive for M. hyopneumoniae were genotyped by multiple-locus variable-number tandem repeat analysis (MLVA). Pigs in Group A showed the highest prevalence and load of M. hyopneumoniae. A positive association was detected between M. hyopneumoniae and Mycoplasma hyorhinis, whereas Actinobacillus pleuropneumoniae was more frequent when the M. hyopneumoniae load was higher. Nevertheless, co-infection had no effect on lung lesion scores. The presence of multiple MLVA types (mixed infections) increased in time only in pigs from Group C and was positively associated with porcine reproductive and respiratory syndrome virus infection. Lung lesions were more severe in pigs with at least one TBS positive for M. hyopneumoniae and in pigs with a history of mixed infections. The central role of M. hyopneumoniae and relevance of mixed infections suggest that increased biosecurity might be beneficial for lung lesion sequelae.

Additional file 1: Table 1. Allele calling table. Each VNTR type is identified as a combination of different VNTR locus. The number of repeats of each locus is determinate by the number of base pair (bp) for that locus.

In 2011, a group A rotavirus was isolated from the brain of a fox with encephalitis and neurologic signs, detected by rabies surveillance in Italy. Intracerebral inoculation of fox brain homogenates into mice was fatal. Genome sequencing revealed a heterologous rotavirus of avian origin, which could provide a model for investigating rotavirus neurovirulence.

There is currently an increased interest in the use of serological approaches in combination with traditional cell-mediated immunity-based techniques to improve the detection of tuberculosis (TB)-infected animals. In the present study, we developed and validated two different serological TB-detection assays using four antigens, MPB70, MPB83, ESAT6 and CFP10, and the tuberculin PPDb. A conventional multi-antigen TB-ELISA method and a novel TB multiplex test, based on Luminex technology, were developed to detect antibodies to multiple antigen targets. The performance levels of the two tests were evaluated and compared using selected panels of samples having known TB states. The TB-ELISA test (containing five antigens, including PPDb) had a sensitivity (Se) of 74.2% and a specificity (Sp) of 94.9%, while the TB-Luminex test had higher Se (79.0%) and Sp (99.1%) rates even when only one reactive antigen was used to classify the test as positive. If a more restrictive criterion, requiring two positive antigens to classify the test as positive, was used, then the TB-ELISA's Sp rate increased to 99.8% but the Se decreased to 61.3%, while the TB-Luminex test's Sp rate increased to 100% but the Se decreased to 51.2%. TB-ELISA and TB-Luminex were applied to a panel of 257 sera collected from bTB-positive herds, as determined by a post-mortem inspection. They showed good performance levels, identifying 49 (80.3%) and 48 (78.7%), respectively, of 61 samples that had tested positive by the intradermal tuberculin (IDT) test and/or interferon-gamma assay. In addition, TB-ELISA and TB-Luminex were able to identify 60 and 42 samples as positive, respectively, out of the 196 samples that tested negative to IDT and interferon-gamma at the time of serum collection. Subsequent IDT tests performed after 1-2 months, confirmed the positivity of 18 samples, indicating the strategic value of having two serological assays to detect TB-infected herds that were not reactive to initial IDT testing, thereby allowing for the rapid control of outbreaks and eradication of the disease.

Contains fulltext : 107786.pdf (Publisher’s version ) (Closed access) Mycobacterium bovis isolates from the Iberian Peninsula are dominated by strains with spoligotype patterns deleted for spacer 21. Whole-genome sequencing of three Spanish strains with spacer 21 missing in their spoligotype pattern revealed a series of SNPs and subsequent screening of a selection of these SNPs identified one in gene guaA that is specific to these strains. This group of strains from the Iberian Peninsula missing spoligotype spacer 21 represents a new clonal complex of M. bovis, defined by the SNP profile with a distinct spoligotype signature. We have named this clonal complex European 2 (Eu2) and found that it was present at low frequency in both France and Italy and absent from the British Isles. 01 juni 2012

We have identified a clonal complex of Mycobacterium bovis isolated at high frequency from cattle in Uganda, Burundi, Tanzania, and Ethiopia. We have named this related group of M. bovis strains the African 2 (Af2) clonal complex of M. bovis. Af2 strains are defined by a specific chromosomal deletion (RDAf2) and can be identified by the absence of spacers 3 to 7 in their spoligotype patterns. Deletion analysis of M. bovis isolates from Algeria, Mali, Chad, Nigeria, Cameroon, South Africa, and Mozambique did not identify any strains of the Af2 clonal complex, suggesting that this clonal complex of M. bovis is localized in East Africa. The specific spoligotype pattern of the Af2 clonal complex was rarely identified among isolates from outside Africa, and the few isolates that were found and tested were intact at the RDAf2 locus. We conclude that the Af2 clonal complex is localized to cattle in East Africa. We found that strains of the Af2 clonal complex of M. bovis have, in general, four or more copies of the insertion sequence IS 6110 , in contrast to the majority of M. bovis strains isolated from cattle, which are thought to carry only one or a few copies.

Spoligotyping and exact tandem repeat (ETR) analysis of Mycobacterium bovis and M. caprae isolated strains has been routinely carried out in Italy since 2000 to obtain a database of genetic profiles and support traditional epidemiological investigations. In this study, we characterized 1,503 M. bovis and 57 M. caprae isolates obtained from 2000 to 2006 in 747 cattle herds mainly located in northern Italy. We identified 81 spoligotypes and 113 ETR profiles, while the combination of spoligotyping/ETR analysis differentiated 228 genotypes, with genotypic diversity indices of 0.70 (spoligotyping), 0.94 (ETR-A to -E typing), and 0.97 (spoligotyping/ETR-A to -E typing), respectively. Despite the high degree of resolution obtained, the spoligotyping/ETR methods were not discriminative enough in the case of genotypes characterized by the combination of SB0120, the predominant spoligotype in Italy, with the most common ETR profiles. To obtain a more informative subset of typing loci, 24 mycobacterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR) markers were evaluated by analyzing a panel of 100 epidemiologically unrelated SB0120 isolates. The panel was differentiated into 89 profiles with an overall genotypic diversity of 0.987 that could be also achieved by using a minimal group of 13 loci: ETR-A, -B, and -E; MIRU 26 and 40; and VNTR 2163a, 2163b, 3155, 1612, 4052, 1895, 3232, and 3336. The allelic diversity index and the stability of single loci was evaluated to provide the most discriminative genotyping method for locally prevalent strains.

Porcine epidemic diarrhea virus (PEDV) has been detected sporadically in Italy since the 1990s. We report the phylogenetic relationship of swine enteric coronaviruses collected in Italy during 2007-2014 and identify a drastic shift in PEDV strain variability and a new swine enteric coronavirus generated by recombination of transmissible gastroenteritis virus and PEDV.

In mammalian cells the product of the human retinoblastoma tumour suppressor gene (pRb) can recruit Rpd3-like histone deacetylases to repress transcription. In this study, we investigated whether this mechanism might also be relevant in plants and found both conserved and distinct features. The expression profiles of the Zea mays Rpd3-type histone deacetylase (ZmRpd3I) and the retinoblastoma-related (ZmRBR1) homologues were analysed during endosperm development. GST pull-down and immunoprecipitation experiments showed a physical interaction between ZmRBR1 and ZmRpd3I. Because ZmRpd3I lacks a LXCXE motif, conserved in several pRb-interacting proteins, we have mapped the amino acid domains involved in the ZmRBR1/ZmRpd3I interaction. Furthermore, we observed that ZmRbAp1, a maize member of the MSI/RbAp family, facilitated this protein interaction. Co-transformations of tobacco protoplasts with plasmids expressing ZmRBR1 and ZmRpd3I showed that the two proteins cooperate in repressing gene transcription. Our findings represent the first indication that in plants a regulator of important biological processes, ZmRBR1, can recruit a histone deacetylase, ZmRpd3I, to control gene transcription.

In mammalian cells the product of the human retinoblastoma tumour suppressor gene (pRb) can recruit Rpd3-like histone deacetylases to repress transcription. In this study, we investigated whether this mechanism might also be relevant in plants and found both conserved and distinct features. The expression profiles of the Zea mays Rpd3-type histone deacetylase (ZmRpd3I) and the retinoblastoma-related (ZmRBR1) homologues were analysed during endosperm development. GST pull-down and immunoprecipitation experiments showed a physical interaction between ZmRBRI and ZmRpd3I. Because ZmRpd3I lacks a LXCXE motif, conserved in several pRb-interacting proteins, we have mapped the amino acid domains involved in the ZmRBR1/ZmRpd3I interaction. Furthermore, we observed that ZmRbAp1, a maize member of the MSI/RbAp family, facilitated this protein interaction. Co-transformations of tobacco protoplasts with plasmids expressing ZmRBRI and ZmRpd3I showed that the two proteins cooperate in repressing gene transcription. Our findings represent the first indication that in plants a regulator of important biological processes, ZmRBRI, can recruit a histone deacetylase, ZmRpd3I, to control gene transcription.