Outbreaks of rabbit hemorrhagic disease have occurred recently in young rabbits on farms on the Iberian Peninsula where rabbits were previously vaccinated. Investigation identified a rabbit hemorrhagic disease virus variant genetically related to apathogenic rabbit caliciviruses. Improved antivirus strategies are needed to slow the spread of this pathogen.

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BackgroundInfections with Mycobacterium bovis and closely related members of the Mycobacterium tuberculosis complex (MTC) are shared between livestock, wildlife and sporadically human beings. Wildlife reservoirs exist worldwide and can interfere with bovine tuberculosis (TB) eradication efforts. The Eurasian wild boar (Sus scrofa) is a MTC maintenance host in Mediterranean Iberia (Spain and Portugal). However, few systematic studies in wild boar have been carried out in Atlantic regions. We describe the prevalence, distribution, pathology and epidemiology of MTC and other mycobacteria from wild boar in Atlantic Spain. A total of 2,067 wild boar were sampled between 2008 and 2012.ResultsThe results provide insight into the current status of wild boar as MTC and Mycobacterium avium complex (MAC) hosts in temperate regions of continental Europe. The main findings were a low TB prevalence (2.6%), a low proportion of MTC infected wild boar displaying generalized TB lesions (16.7%), and a higher proportion of MAC infections (4.5%). Molecular typing revealed epidemiological links between wild boar and domestic – cattle, sheep and goat – and other wildlife – Eurasian badger (Meles meles) and red fox (Vulpes vulpes) – hosts.ConclusionsThis study shows that the likelihood of MTC excretion by wild boar in Atlantic habitats is much lower than in Mediterranean areas. However, wild boar provide a good indicator of MTC circulation and, given the current re-emergence of animal TB, similar large-scale surveys would be advisable in other Atlantic regions of continental Europe.

Bovine tuberculosis (TB) infection is infrequently diagnosed in sheep. Most reports are from single individual cases or flock outbreaks. However, in Spain several outbreaks have been reported recently, all of which had epidemiological links with TB-infected cattle herds. A total of 897 sheep suspected of being infected with TB and belonging to 23 flocks cohabiting with TB-infected cattle herds and/or goats were tested between 2009 and 2013 in Galicia (north-western Spain), using pathological, immunological and molecular techniques. Of these, 50.44% were positive by culture, 83.23% by histopathology and 24.92%, 4.86% and 59.42% by single intradermal tuberculin test (SITT), interferon-γ and ELISA, respectively. Results suggest that in circumstances akin to those in our study, sheep may be considered as a potential source of TB. We conclude that under similar conditions, serious consideration should be given to TB testing sheep, as they may represent a potential risk to other susceptible co-habiting species. The SITT and ELISA are recommended as the simplest and most cost-effective initial approaches for the diagnosis of TB in sheep under field conditions. However, when possible, interferon-γ should be applied to increase sensitivity.

Paratuberculosis is chronic granulomatous enteritis of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). Whole RNA-sequencing (RNA-Seq) is a promising source of novel biomarkers for early MAP infection and disease progression in cattle. Since the blood transcriptome is widely used as a source of biomarkers, we analyzed whether it recapitulates, at least in part, the transcriptome of the ileocecal valve (ICV), the primary site of MAP colonization. Total RNA was prepared from peripheral blood (PB) and ICV samples, and RNA-Seq was used to compare gene expression between animals with focal or diffuse histopathological lesions in gut tissues versus control animals with no detectable signs of infection. Our results demonstrated both shared, and PB and ICV-specific gene expression in response to a natural MAP infection. As expected, the number of differentially expressed (DE) genes was larger in the ICV than in the PB samples. Among the DE genes in the PB and ICV samples, there were some common genes irrespective of the type of lesion including the C-X-C motif chemokine ligand 8 (CXCL8/IL8), apolipoprotein L (APOLD1), and the interferon inducible protein 27 (IFI27). The biological processes (BP) enriched in the PB gene expression profiles from the cows with diffuse lesions included the killing of cells of other organism, defense response, immune response and the regulation of neutrophil chemotaxis. Two of these BP, the defense and immune response, were also enriched in the ICV from the cows with diffuse lesions. Metabolic analysis of the DE genes revealed that the N-glycan biosynthesis, bile secretion, one-carbon pool by folate and purine metabolism were significantly enriched in the ICV from the cows with focal lesions. In the ICV from cows with diffuse lesions; the valine, leucine and isoleucine degradation route, purine metabolism, vitamin digestion and absorption and the cholesterol routes were enriched. Some of the identified DE genes, BP and metabolic pathways will be studied further to develop novel diagnostic tools, vaccines and immunotherapeutics.