Hypoxia-associated markers in the prognosis of oral canine melanoma

Canine oral malignant melanoma (COMM) is the most common neoplasm in the oral cavity characterized by local invasiveness and high metastatic potential. Hypoxia represents a crucial feature of the solid tumor microenvironment promoting cancer progression and drug resistance. Hypoxia-inducible factor-1α (HIF-1α) and its downstream effectors, vascular endothelial growth factor A (VEGF-A), glucose transporter isoform 1 (GLUT1), C-X-C chemokine receptor type 4 (CXCR4), and carbonic anhydrase IX (CAIX), are the main regulators of the adaptive response to low oxygen availability. The prognostic value of these markers was evaluated in 36 COMMs using immunohistochemistry. In addition, the effects of cobalt chloride-mediated hypoxia were evaluated in 1 primary COMM cell line. HIF-1α expression was observed in the nucleus, and this localization correlated with the presence or enhanced expression of HIF-1α-regulated genes at the protein level. Multivariate analysis revealed that in dogs given chondroitin sulfate proteoglycan-4 (CSPG4) DNA vaccine, COMMs expressing HIF-1α, VEGF-A, and CXCR4 were associated with shorter disease-free intervals (DFI) compared with tumors that were negative for these markers (P = .03), suggesting hypoxia can influence immunotherapy response. Western blotting showed that, under chemically induced hypoxia, COMM cells accumulate HIF-1α and smaller amounts of CAIX. HIF-1α induction and stabilization triggered by hypoxia was corroborated by immunofluorescence, showing its nuclear translocation. These findings reinforce the role of an hypoxic microenvironment in tumor progression and patient outcome in COMM, as previously established in several human and canine cancers. In addition, hypoxic markers may represent promising prognostic markers, highlighting opportunities for their use in therapeutic strategies for COMMs.

Animal models of Soft Tissue Sarcoma for alternative anticancer therapy studies: characterization of the A-72 Canine Cell Line

Canine Soft Tissue Sarcoma (STS) cell line A-72 has been largely employed for antiviral and antiproliferative studies. However, there are few information on their characteristics. Our aim was to evaluate A-72 expression level of genes and proteins involved in the innate immune response and cell cycle, their ability to respond to infective stressors and their possible use as a cellular model for anti-cancer studies in human and animal medicine. For this purpose, we evaluated the basal expression of immune-related, cell cycle and DNA repair genes on this cell line and tumoral tissues. A-72 ability to respond to a wild-type strain of Salmonella typhimurium was assessed. S. typhimurium showed ability to penetrate A-72 causing pro-inflammatory response accompanied by a decrease of cell viability. IL10 and IL18 genes were not expressed in A-72 while CXCL8, NOS2, CXCR4 and PTEN were highly expressed in all samples and TP53 was slightly expressed, as shown in human STS. Our results outline the ability of A-72 to respond to a bacterial agent by modifying the expression of important genes involved in innate immune response and provide a useful model for in vitro evaluation of new therapeutic approaches that could be translated into the human oncology.

Brucella ceti Infection in Striped Dolphins from Italian Seas: Associated Lesions and Epidemiological Data

Brucella ceti infections have been increasingly reported in cetaceans. In this study, we analyzed all cases of B. ceti infection detected in striped dolphins stranded along the Italian coastline between 2012 and 2021 (N = 24). We focused on the pathogenic role of B. ceti through detailed pathological studies, and ad hoc microbiological, biomolecular, and serological investigations, coupled with a comparative genomic analysis of the strains. Neurobrucellosis was observed in 20 animals. The primary histopathologic features included non-suppurative meningoencephalitis (N = 9), meningitis (N = 6), and meningoencephalomyelitis (N = 5), which was also associated with typical lesions in other tissues (N = 8). Co-infections were detected in more than half of the cases, mostly involving Cetacean Morbillivirus (CeMV). The 24 B. ceti isolates were assigned primarily to sequence type 26 (ST26) (N = 21) and, in a few cases, ST49 (N = 3). The multilocus sequence typing (cgMLST) based on whole genome sequencing (WGS) data showed that strains from Italy clustered into four genetically distinct clades. Plotting these clades onto a geographic map suggests a link between their phylogeny and the topographical distribution. These results support the role of B. ceti as a primary neurotropic pathogen for striped dolphins and highlight the utility of WGS data in understanding the evolution of this emerging pathogen.

Epidemiological and genetic analysis of Cetacean Morbillivirus circulating on the Italian coast between 2018 and 2021

Cetacean morbillivirus (CeMV) has caused several outbreaks, unusual mortality events, and interepidemic single-lethal disease episodes in the Mediterranean Sea. Since 2012, a new strain with a northeast (NE) Atlantic origin has been circulating among Mediterranean cetaceans, causing numerous deaths. The objective of this study was to determine the prevalence of CeMV in cetaceans stranded in Italy between 2018 and 2021 and characterize the strain of CeMV circulating. Out of the 354 stranded cetaceans along the Italian coastlines, 113 were CeMV-positive. This prevalence (31.9%) is one of the highest reported without an associated outbreak. All marine sectors along the Italian coastlines, except for the northern Adriatic coast, reported a positive molecular diagnosis of CeMV. In one-third of the CeMV-positive cetaceans submitted to a histological evaluation, a chronic form of the infection (detectable viral antigen, the absence of associated lesions, and concomitant coinfections) was suspected. Tissues from 24 animals were used to characterize the strain, obtaining 57 sequences from phosphoprotein, nucleocapsid, and fusion protein genes, which were submitted to GenBank. Our sequences showed the highest identity with NE-Atlantic strain sequences, and in the phylogenetic study, they clustered together with them. Regarding age and species, most of these individuals were adults (17/24, 70.83%) and striped dolphins (19/24, 79.16%). This study improves our understanding on the NE-Atlantic CeMV strain in the Italian waters, supporting the hypothesis of an endemic circulation of the virus in this area; however, additional studies are necessary to deeply comprehend the epidemiology of this strain in the Mediterranean Sea.

Interdisciplinary approach to solve unusual mortalities in the European common frog (Rana temporaria) in two high-mountain ponds affected by climate change

The global decline in amphibian populations is a major environmental issue. Chytridiomycosis, Ranaviruses and the red-leg syndrome have been identified in unusual mortality events. However, these infections do not account for all causes of declining amphibian populations. Moreover, several cases of amphibian mortality are difficult to solve without resorting to an interdisciplinary approach. Two cases of unusual mortality in Rana temporaria occurred at two high-mountain ponds (northwest Italy) in April and May 2021. Water and frog samples were analysed to understand the possible causes responsible for the unusual mortalities. Results of the main physicochemical (pH, conductivity, dissolved oxygen, chemical and biochemical oxygen demand) and nutrient (ammonia/ammonium, nitrite, nitrate, total phosphorus) parameters revealed a good condition of the water quality, with the absence of the main cyanotoxins (microcystins/nodularins). However, unseasonably high spring water temperatures were recorded in both ponds (12.73 °C and 14.21 °C for Frog Pond and Selleries Pond, respectively). Frogs (n = 50; snout-vent length: 7.0-9.8 cm; body mass: 85-123 g) collected from Frog Pond mainly presented bumps on the ventral cavity and dermal ulceration associated with the isolation of Carnobacterium maltaromaticum. On the other hand, frogs (n = 5; snout-vent length: 8.0-9.1 cm; body mass: 87-92 g) from Selleries Pond presented petechiae and dermal ulcerations on the rear limbs associated with the isolation of Aeromonas salmonicida and A. sobria. In both mortality events, the interdisciplinary approach revealed an association between frog mortalities and the isolation of bacteria. Isolated bacteria are considered opportunistic pathogens, and the high values of the water temperature has certainly led a stress on the frogs, favouring the spread of bacteria and the death of the frogs. Further studies are needed to assess the pathophysiological effects of the opportunistic bacteria here isolated, clarifying the interactions between emerging pathogens and climate change.

Safety and Effects of a Commercial Ozone Foam Preparation on Endometrial Environment and Fertility of Mares

Mares' subfertility represents a complex diagnostic and therapeutic challenge and both clinical and subclinical endometritis are considered major causes of impaired fertility. Thanks to its properties, ozone has a big potential as a treatment for equine endometritis. Therefore, the aim of this study is to describe the safety and the effects on endometrium and reproductive parameters of mares of a commercial ozone foam preparation (Riger Spray®). Twenty-four mares were treated during estrus: ozone group with an intrauterine instillation of ozone foam preparation (OG, n=16) and control group with 20 ml of lactated Ringer's solution (CG, n=8). Samples for endometrial cytology were collected before the ozone treatment (T0), after 24 h (T1), after one week (T2), two weeks (T3), and when the subsequent estrous phase was detected (T4). Furthermore, samples for histological examination and uterine swab for bacteriological examination were collected at T0 and T4. At T1, a statistically significant increase of endometrial inflammation in the OG mares compared to T0 (P<.05) and to CG at same time point (P<.05) was observed, but it was already resolved at T2. No differences in endometrial inflammation in CG, biopsy grade before and after the treatment in the two groups, number of mares pregnant at the end of the season and number of mares pregnant at the first cycle were observed. However, the number of inseminations required for pregnancy tended to be lower (P=.0711) in the OG (1.69±0.06) than in CG mares (2.60±0.89).

Renal carcinoma with metastatic spread in a tiger (Panthera tigris): morphological and immunohistochemical study

A 12‑year‑old intact male Panthera tigris presented with pain and weight loss was euthanatized. Necroscopical examination revealed a neoplastic mass expanding to the left renal pelvis with metastatic dissemination to local lymph node, adrenal gland, and lung. Immunohistochemical characterization was performed revealing co‑expression of both cytokeratin and vimentin and negativity for both PAX8 and c‑KIT. Considering histochemical and immunohistochemical results the tumour was classified as renal cell carcinoma with metastatic spread. This report provides insights into the morphological and immunohistochemical features of renal cell carcinoma in Panthera tigris.

Investigating a Prognostic Factor for Canine Hepatocellular Carcinoma: Analysis of Different Histological Grading Systems and the Role of PIVKA-II

BACKGROUND

Hepatocellular carcinoma (HCC) in dogs is uncommon and often associated with a good prognosis, although some cases prove to be aggressive. In human oncology HCC is often very aggressive and diagnostic methods and prognostic factors are widely used to predict its biological behaviour. These include the expression of PIVKA-II.

METHODS

in order to identify a prognostic factor for canine HCC, we applied different methods of histological grading and investigated PIVKA-II expression in 22 HCC of dogs treated surgically and followed clinically for at least 2 years.

RESULTS

Nineteen patients analysed have passed the observation period without tumour recurrence, while 3 died following the development of metastases. PIVKA-II was positive in 15/22 cases without correlation with prognosis or tumoural grading even if a trend of PIVKA-II negativity in low WHO grades as well as increased number of PIVKA-II positive cases in higher WHO grades weres observed.

CONCLUSIONS

This work showed that, PIVKA-II cannot be considered either as a marker of malignancy or as a prognostic marker for canine HCC. The poor prognosis depends usually on the clinical presentation. Thus prognostic parameters in canine HCC able to predict its aggressive behaviour through histological examination are still missing. The most promising method, limited to our study, seems to be the WHO histological grading.

Toxoplasma gondii Genetic Diversity in Mediterranean Dolphins

Toxoplasma gondii constitutes a major zoonotic agent but also has been frequently identified as an important cause of clinical disease (e.g., abortion, pneumonia, encephalitis) in wildlife; specifically, T. gondii has been associated with neurological disease in cetaceans. This study investigated the genetic diversity of T. gondii strains involved in infections in dolphins found stranded in the Mediterranean coastlines of Italy. Tissue samples from 16 dolphins (Stenella coeruleoalba and Tursiops truncatus species) positive for T. gondii-DNA presence by PCR were examined by histology and subjected to further genetic characterization of strains detected by PCR-RFLP and multilocus PCR-sequencing assays. According to fully genotyped samples, the genotypes ToxoDB#3 (67%) and #2 (22%) were detected, the latter being reported for the first time in cetaceans, along with a mixed infection (11%). Subtyping by PCR-seq procedures provided evidence of common point mutations in strains from southwestern Europe. Despite evidence of T. gondii as a cause of neurological disease in dolphins, sources of infections are difficult to identify since they are long-living animals and some species have vast migration areas with multiple chances of infection. Finally, the genetic diversity of T. gondii found in the dolphins studied in the Mediterranean coastlines of Italy reflects the main genotypes circulating inland in the European continent.

Multi-Level System to Assess Toxicity in Water Distribution Plants

The toxicity of water samples from water distribution plants needs to be investigated further. Indeed, studies on the pro-oxidant effects driven by tap water are very limited. In this study, the water quality, pro-oxidant effects, and potential health risks driven by exposure to groundwater samples from two water plants (sites A and B) located in Northwestern Italy were investigated in a multi-level system. Physicochemical parameters and the absence of pathogens, cyanotoxins, and endocrine active substances indicated a good water quality for both sites. The 25 metals analyzed were found under the limit of quantification or compliant with the maximum limits set by national legislation. Water samples were concentrated by the solid-phase extraction system in order to assess the aquatic toxicity on Epithelioma papulosum cyprini (EPC) cell line. Levels of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, and glutathione reductase were evaluated through the Integrated Biomarkers Response (IBRv2) index. EPC cell line was found a sensible model for assessing the antioxidant responses driven by both water concentrates. A similar antioxidant response was shown by plots and IBRv2 suggesting a muted risk for the two sampling sites.

Pulmonary fibrosis in a dog as a sequela of infection with Severe Acute Respiratory Syndrome Coronavirus 2? A case report

Background

Interstitial lung disease is a heterogeneous group of conditions characterized by severe radiographic changes and clinicopathological findings. However, in the vast majority of cases, the cause remains unknown.

Case description

In the present study, we reported the clinical case of a 3 years old female Bull Terrier presented in October 2020 to the Advanced Diagnostic Imaging Department of the Turin Veterinary Teaching Hospital with a progressive pulmonary illness characterized by dyspnea, exercise intolerance, and a diffuse and severe pulmonary interstitial pattern at imaging investigations.

Considering the clinical findings, the dog was included in a serological survey for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in companion animals, showing positive results. Due to the further clinical worsening, the owners opted for euthanasia. At necroscopy, dog showed severe and chronic bronchopneumonia compatible with a Canine Idiopathic Pulmonary Fibrosis and with serological features linked to a SARS-CoV-2 infection.

Conclusions

The comparison of these lesions with those reported in humans affected by Coronavirus Disease 2019 (COVID-19) supports the hypothesis that these findings may be attributable to the post-acute sequelae of SARS-CoV-2 infection in a dog with breed predisposition to Canine Idiopathic Pulmonary Fibrosis (CIPF), although direct evidence of SARS-CoV-2 by molecular or antigenic approaches remained unsolved.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03191-x.

Validation of suitable reference genes for quantitative expression analysis by qPCR in bovine terminal ileum and ileocecal valve

The use of reference genes is commonly accepted as the most reliable approach to normalize qRT-PCR and to reduce possible errors in the quantification of gene expression. The aim of this study was to identify a set of reference genes suitable for gene expression analysis in the distal portion of small intestine and ileocecal valve in cattle. These sites of intestine are of interest in veterinary science as they are the main sites of inflammation caused by Mycobacterium avium subsp. paratuberculosis, agent of paratuberculosis. We employed ten PCR assays for commonly used reference genes belonging to various functional classes and then determined their expression stability. The most stable genes were RPL13A and HMBS, followed by TFRC and B-ACT. NormFinder analysis provided similar results with B-ACT as the best reference gene, followed by RLP13A and TFRC. This validated gene panel may be useful for studies on paratuberculosis aiming to identify genes differentially expressed by qRT-PCR.

Investigation of Potential Reservoirs of Non-Tuberculous Mycobacteria in a European Sea Bass (Dicentrarchus labrax) Farm

Fish mycobacteriosis is a widespread global problem caused by species of non-tuberculous mycobacteria (NTM). Mycobacterium marinum is one of the species most often involved in disease episodes of aquarium and farmed fish. Since there is currently no available effective therapy or vaccine, a prompt search for routes of entry is key to limiting the damage induced by the disease. Here we report a case of mycobacteriosis follow up in a European sea bass (Dicentrarchus labrax) farm located in Northern Italy, in which environmental samples and newly added fish batches were analyzed. Samples from fish present on the farm, sediment, and periphyton all resulted positive for M. marinum, whereas the new fish batches and the water samples resulted negative. The environmental resistance of NTM (alcohol-acid resistance, biofilm formation) and the lack of prophylactic and therapeutic strategies make these diseases difficult to manage. Prompt identification of biotic and abiotic reservoirs, combined with good zootechnical hygiene practices, are the most effective measures to control fish mycobacteriosis in intensive farms.

Retrospective immunohistochemical investigation on dolphin morbillivirus infection by comparing the performance of heterologous monoclonal and polyclonal antibodies - Short communication

Dolphin morbillivirus (DMV) is a pathogen of great concern in free-ranging cetaceans. Confirmation and staging of morbillivirus infections rely on histology and immunohistochemistry (IHC), following molecular detection. As at the present time no specific antibodies (Abs) against DMV are available, two heterologous Abs have been used worldwide for the examinations of morbillivirus infections of cetaceans. One is a monoclonal Ab (MoAb) prepared against the N protein of canine distemper virus (CDV), whereas the other is a polyclonal Ab raised in rabbits against rinderpest virus (RPV). Both Abs are known to show cross-reactivity with DMV. In this study we compared the labelling quality and the neuroanatomical distribution of staining with these two Abs by means of IHC analysis. To this end, serial sections of the target organs from ten free-ranging stranded cetaceans, previously diagnosed as being infected with DMV by PCR and/or serology, were subjected to IHC. The brain, lungs and lymph nodes of one animal were found to be positive with both Abs. From two other animals, the brain and the spleen, respectively, tested positive only with the polyclonal Ab. In the positive brain tissues, multifocal immunostaining was observed, with similar staining location and extent, with the two antibodies tested. Our results suggest that the polyclonal anti-RPV Ab might have a stronger binding activity to DMV than the anti-CDV MoAb. Nevertheless, the elaboration and use of specific anti-DMV Abs might be essential to guarantee conclusive results in diagnostic and pathogenetic investigations.

Evidence for Unknown Sarcocystis-Like Infection in Stranded Striped Dolphins (Stenella coeruleoalba) from the Ligurian Sea, Italy

Simple Summary

Two stranded striped dolphins presented meningoenchepalitic lesions associated with the presence of unknown protozoan tissue cysts. The present study aimed at fully characterizing these previously undescribed parasites. Light microscopy re-examination of affected CNS areas showed high numbers of tissue cysts with morphological features resembling those of Sarcocystis species. Tissue cyst bradyzoites positively stained when labeled with polyclonal antisera but cross-reactivity could not be precluded. Sarcocystis sp. sequences with high homology to species infecting livestock were amplified by means of PCR from myocardial and muscle tissues. This is the first report of Sarcocystis-like tissue cysts in the cerebral tissue of stranded cetaceans with muscular sarcocystosis in Mediterranean dolphins. The obtained results may suggest a land-to-sea cycling of Apicomplexan parasites in this region and the need for further investigations in order to foster marine mammal conservation.

Abstract

Two striped dolphins (SD1, SD2), stranded along the Ligurian coast of Italy, were diagnosed with a nonsuppurative meningoencephalitis associated with previously undescribed protozoan tissue cysts. As tissue cysts were morphologically different from those of Toxoplasma gondii, additional histopathological, immunohistochemical, ultrastructural, and biomolecular investigations were performed, aiming to fully characterize the organism. Histopathology revealed the presence of large Sarcocystis-like tissue cysts, associated with limited inflammatory lesions in all CNS areas studied. IHC was inconclusive, as positive staining with polyclonal antisera did not preclude cross-reaction with other Sarcocystidae coccidia. Applied to each animal, 11 different PCR protocols precluded a neural infection by Sarcocystis neurona, Sarcocystis falcatula, Hammondia hammondi, and Neospora caninum. T. gondii coinfection was confirmed only in dolphin SD2. Sarcocystis sp. sequences, showing the highest homology to species infecting the Bovidae family, were amplified from SD1 myocardium and SD2 skeletal muscle. The present study represents the first report of Sarcocystis-like tissue cysts in the brain of stranded cetaceans along with the first description of Sarcocystis sp. infection in muscle tissue of dolphins from the Mediterranean basin.

White-Nose Syndrome Confirmed in Italy: A Preliminary Assessment of Its Occurrence in Bat Species

Although no mass mortality has been recorded so far, the precise demographic effect of white-nose syndrome (WNS) on European bats still remains to be ascertained. Following the first isolation of P. destructans in Italy, further surveys were performed to assess the distribution of the fungus in NW Italy and its effects on bats. Data were collected from March 2019 to April 2020 at sites used for hibernation (six sites) and/or for reproduction (four sites) in Piedmont and Aosta Valley. A total of 138 bats, belonging to 10 species, were examined to identify clinical features possibly related to the fungal presence. Culture from swabs and the molecular identification of isolates confirmed the presence of P. destructans in bats from five sites, including two maternal roosts. Dermal fungal infiltration, the criterion to assess the presence of WNS, was observed in biopsies of bats belonging to Myotis blythii, M. daubentonii, M. emarginatus and M. myotis. This is the first report of the disease in Italy. The results suggest a greater susceptibility to the infection of the genus Myotis and particularly of M. emarginatus, possibly due to the long length of its hibernation period. Other fungal dermatophytes were also observed.

The unusual isolation of carnobacteria in eyes of healthy salmonids in high-mountain lakes

Carnobacteria are common bacteria in cold and temperate environments; they are also reported during fish mortality events. In a previous study, carnobacteria were isolated from the eyes of healthy wild salmonids from a high-mountain lake. To better understand these findings, salmonids were captured from three high-mountain lakes (Lower and Upper Balma Lake, Rouen Lake; northwest Italy) during August 2019 and subjected to bacteriological and histological examination. Although all were healthy, 8.7% (Lower Balma Lake), 24% (Upper Balma Lake), and 32.6% (Rouen Lake) were positive for carnobacteria colonization of the eyes. A Trojan-horse effect was hypothesized to explain carnobacteria isolation in the eye. This immune-escaping macrophage-mediated mechanism has been identified in other Gram-positive bacteria. Biochemical, molecular, and phylogenetic analysis were carried out on isolated bacteria (Carnobacterium maltaromaticum and C. divergens). Based on previous references for carnobacteria isolated from fish, C. maltaromaticum strains were tested for the pisA precursor gene of the bacteriocin piscicolin 126. Carnobacterium maltaromaticum strains were found to display genotypic heterogeneity and a low percentage of pisA positive amplification. Features of geomorphology, geographic isolation, and microbiota common to the three lakes are thought to be possibly related to our findings. Moreover, terrestrial insects collected from the lake shoreline and the stomach contents were screened for the presence of carnobacteria. The salmonids in these high-mountain environments feed mainly on terrestrial insects, which are considered possible vectors for carnobacteria that might catabolize the exoskeleton chitin. All insects tested negative for carnobacteria, but as a small number of samples were analyzed, their role as possible vectors of infection cannot be excluded. Further studies are needed to corroborate our research hypothesis.

Polymorphisms associated to bovine paratuberculosis: investigation of their role in DNA-protein interactions and transcriptional regulation

Previous studies led to identify SNPs in putative regulatory regions of the SLC11A1 and CARD15 genes with association to paratuberculosis in cattle. Aim of this study was to investigate the role of these mutations at the regulatory level by DNA-protein interaction analyses and transcriptome comparison between wild-type and mutated animals. Gene regions carrying the SNPs of interest were analysed by bioinformatic tools to predict allele-dependent binding sites for transcription factors (TFBS). Putative TFBS were in vitro explored by Electrophoretic Mobility Shift Assays (EMSA). EMSA did not show specific gel shifts for any allele indicating that these SNPs may eventually influence gene transcription without altering TFBS. Whole transcriptome expression analysis was performed on intestinal tissues of wild-type and mutated cattle by RNA-Seq. Differential regulation of five genes involved in innate immune system was detected. Specifically, ULBP3 was down-regulated, while S100A8, S100A12, LOC510860, and IFI27 were up-regulated. In previous studies, ULBP3, S100A8, and S100A12 resulted differentially expressed in cattle affected by paratuberculosis, suggesting a possible implication in the pathogen response. Further investigations are needed to elucidate the functional role of these SNPs and to understand the gene network involved in the interactions between non-coding SNPs and other genome regions.

Occurrence of Brucella ceti in striped dolphins from Italian Seas

Brucella ceti infections have been increasingly reported in cetaceans, although a very limited characterization of Mediterranean Brucella spp. isolates has been previously reported and relatively few data exist about brucellosis among cetaceans in Italy. To address this gap, we studied 8 cases of B. ceti infection in striped dolphins (Stenella coeruleoalba) stranded along the Italian coastline from 2012 to 2018, investigated thanks to the Italian surveillance activity on stranded cetaceans. We focused on cases of stranding in eastern and western Italian seas, occurred along the Apulia (N = 6), Liguria (N = 1) and Calabria (N = 1) coastlines, through the analysis of gross and microscopic findings, the results of microbiological, biomolecular and serological investigations, as well as the detection of other relevant pathogens. The comparative genomic analysis used whole genome sequences of B. ceti from Italy paired with the publicly available complete genomes. Pathological changes consistent with B. ceti infection were detected in the central nervous system of 7 animals, showing non-suppurative meningoencephalitis. In 4 cases severe coinfections were detected, mostly involving Dolphin Morbillivirus (DMV). The severity of B. ceti-associated lesions supports the role of this microbial agent as a primary neurotropic pathogen for striped dolphins. We classified the 8 isolates into the common sequence type 26 (ST-26). Whole genome SNP analysis showed that the strains from Italy clustered into two genetically distinct clades. The first clade comprised exclusively the isolates from Ionian and Adriatic Seas, while the second one included the strain from the Ligurian Sea and those from the Catalonian coast. Plotting these clades onto the geographic map suggests a link between their phylogeny and topographical distribution. These results represent the first extensive characterization of B. ceti isolated from Italian waters reported to date and show the usefulness of WGS for understanding of the evolution of this emerging pathogen.

Intracranial squamous cell carcinoma in an Ovis aries

Squamous cell carcinoma (SCC) is a malignant mucoepithelial tumor that affects pets and farm animals. Common sites are dorsal areas and/or areas of poor skin pigmentation exposed to mutagenic ultraviolet (UV) radiation. Novel ovine papillomavirus (OaPV3) was recently described in SCC lesions in Sardinia breed ovines. In 2017, a 7‑year‑old half‑breed aries was presented with symptoms compatible with a vestibular syndrome. The animal was euthanized 1 month after the onset of clinical signs due to a lack of response to treatment and poor prognosis. A complete postmortem examination was performed. Necropsy revealed only a loss of incisors, associated with alveolar necrotic osteomyelitis, and left unilateral purulent nasal discharge. No other thoracic or abdominal lesions were observed. Opening of the skull revealed a cauliflower‑like space‑occupying mass. Histological examination showed trabecules and islands of squamous, neoplastic epithelial cells with the formation of concentric keratin layers. This raised the suspicion of SCC, which was confirmed with cytokeratin‑positive immunostaining. Simplex PCR on the frozen tissue mass was negative for OaPV1, OaPV2, and OaPV3. This case report suggests that SCC, although rare, should be included in the differential diagnosis of cases of vestibular disorder.

Equus caballus papillomavirus type 2 (EcPV2) in co-occurring vulvar and gastric lesions of a pony

In horses, squamous cell carcinomas (SCCs) are the most common malignant tumors developing on non-pigmented skin, muco-cutaneous areas, like external genitalia, and, less frequently, in the stomach. Growing evidence suggests Equus caballus papillomavirus type 2 (EcPV2) as causative agent of genital SCCs. Our case report describes a 20-year-old, female, mixed-breed pony with co-occurring vulvar papilloma and in situ carcinoma and gastric SCC. Both lesions were positive for the same EcPV2, as confirmed by DNA sequencing. E6 mRNA expression was observed both in vulvar lesions and gastric SCC, while L1 mRNA was expressed in the vulvar tumor. To the best of the Authors' knowledge, this is the first report of an association between EcPV2 and equine gastric squamous cell carcinoma, with co-occurring EcPV2-positive genital lesions. Further studies are required to assess the real prevalence and the possible role of this viral type in these equine tumors.

Microbiological and Histological Analysis for the Evaluation of Farmed Mussels (Mytilus galloprovincialis) Health Status, in Coastal Areas of Italy

Shellfish farming is a relevant economic activity in Italy. The Gulf of La Spezia is one of the major production areas for mussels: the area is characterized by the presence of numerous human activities that could harm the quality of seawater. Additionally, the presence of potentially pathogenic microorganisms may influence the health status of animals, which must be constantly monitored. To have a clear view of the health conditions of the mussels (Mytilus galloprovincialis) farmed in this area, microbiological, parasitological, and histological analyses were performed. The study was conducted from November 2016 to October 2017. Overall, despite the presence of potentially pathogenic microorganisms for mussels, abnormal mortality rates were not reported during the monitoring period and the histological examination revealed no significant lesions. Our study confirms that studying different aspects together is a useful tool for assessing the health conditions of mussels and points out the importance of adverse environmental conditions for the expression of the pathogenicity of microorganisms.

Distinguishing between Fresh and Frozen-Thawed Smoked Salmon: Histology To Detect Food Adulteration in High-Value Products

The issue of food safety has acquired increased importance, and fraud is a major concern for the food industry. Among different types of food adulteration, there is the sale of frozen-thawed smoked salmon product as fresh, which not only decreases the quality of products but also misleads consumers and may involve associated health risks. In response to this problem, we tested the performance of histology to identify smoked salmon as fresh or frozen-thawed as a valid analytical method, so food business operators and official controllers can reliably and correctly classify the storage state of the product. Three groups of samples were prepared: group A (n = 36), fresh samples; group B (n = 36), frozen at -18°C for 30 days; and group C (n = 36), stored at -3°C for 30 days after packaging. Two histopathologists examined all samples in blind evaluations and classified them as fresh or frozen-thawed. Sensitivity, specificity, and interrater agreement were calculated. Results show high performance with the test: 80.6% sensitivity (95% confidence intervals [CI]: 64 to 91.8%); 95.6% specificity (95% CI: 89.1 to 98.8%); and Cohen's kappa was 0.81 (95% CI: 0.64 to 0.98%). Histology is a reliable and highly accurate method to differentiate fresh from frozen-thawed smoked salmon and could be used by the industry and official controllers to verify the labeling of the commercial product.

First report of Salmonella 1,4,[5],12:i:- in free-ranging striped dolphins (Stenella coeruleoalba), Italy

Between 2015 and the beginning of 2018 (January-March), 30 cetaceans were found stranded along the Ligurian Sea coast of Italy. Necropsies were performed in 22 cases and infectious diseases resulted the most common cause of death. Three striped dolphins, showed a severe coinfection involving the monophasic variant of Salmonella Typhimurium (Salmonella 1,4,[5],12:i:-). The isolates were characterized based on antimicrobial resistance, Multiple-Locus Variable-number tandem-repeat Analysis (MLVA) and whole-genome sequencing (WGS). All isolates demonstrated the same multidrug resistant genotype (ASSuT isolates), showed three different MLVA profiles, two of which closely related, and were identified as Sequence Type 34. Moreover, Single nucleotide polymorphisms (SNP) analysis confirmed strong correlations between two out of the three isolates. To our knowledge, S. 1,4,[5],12:i:-, one of the most common serovars in cases of human infection and food sources worldwide, has not previously been described in marine mammals, and reports of Salmonella-associated disease in free-ranging cetaceans are rare. These results highlight the role of cetaceans as sentinel species for zoonotic and terrestrial pathogens in the marine environment, suggest a potential risk for cetaceans and public health along the North Western Italian coastline and indicate cetaceans as a novel potential reservoir for one of the most widespread Salmonella serovars.

Feline calicivirus infection in cats with virulent systemic disease, Italy

Feline calicivirus (FCV) is a contagious viral pathogen that usually causes a mild, self-limiting respiratory disease. More recently, highly virulent FCV strains have emerged and have been associated with severe systemic infection, referred to as virulent systemic disease (VSD). The objective of this study is to report VSD cases in Italian cats along with the molecular characterization of two detected FCV strains. Three client-owned cats showed clinical signs resembling to those described for VSD cases. The cats were subjected to molecular investigations for detection of FCV and other feline pathogens. Histopathology and immunohistochemistry were performed on internal organs of one cat; molecular characterization of two detected FCV strains was obtained through sequence and phylogenetic analyses. Putative VS-FCV strains were detected in all three cats, which were co-infected with feline panleukopenia virus. The cat submitted to histopathology and immunohistochemistry displayed severe histological changes and FCV antigens in internal organs. Two Italian FCV strains, for which amplification of ORF2 was successful, were strictly related and formed a unique phylogenetic cluster. These viruses did not show consistent changes in the amino acid sequences with respect to reference VS-FCVs. The results of our study confirm that VS-FCV strains are circulating in Italy and that VSD diagnosis is complicated since both genetic and clinical markers have not been identified so far.

Novel dolphin morbillivirus (DMV) outbreak among Mediterranean striped dolphins Stenella coeruleoalba in Italian waters

An unusual mortality event (UME) of striped dolphins Stenella coeruleoalba occurred in the period July to December 2016 along the Italian Ionian coastline. We conducted a complete postmortem examination on 28 specimens and detected dolphin morbillivirus (DMV), by means of biomolecular analyses, in the target tissues of 17 animals. Unlike previous outbreaks occurring in the Mediterranean Sea in 2011 and 2013, we observed typical pathological changes suggestive of morbilliviral infection in an acute/subacute phase and immunohistochemical reactivity. The same findings were observed in 13 other specimens beached along the Italian coastline during 2016 with no temporal and geographical relationship with the ongoing epidemic outbreak. Molecular characterization and phylogenetic analysis showed that DMV sequences detected in Italy in 2016 clustered with those identified in Portugal and Galicia (Spain), representing a novel DMV strain of Atlantic origin which entered the Mediterranean Sea and affected a naïve striped dolphin population. DMV sequences detected in the previous Mediterranean outbreaks exhibited a marked genetic relatedness and diverged from those detected in cetaceans stranded along the Galician and Portuguese coasts since 2007.

A novel divergent group of Ostreid herpesvirus 1 μVar variants associated with a mortality event in Pacific oyster spat in Normandy (France) in 2016

The acute course of disease in young oysters infected by OsHV-1 and the rapid tissue degradation often preclude histological examination of specimens collected during outbreaks in field. Herein, live spat originated from two geographical areas were sampled just at the onset of a mortality event that occurred in Normandy (France) in June 2016. The lesions, associated with high OsHV-1 DNA quantities, were characterized by severe and diffuse haemocytosis mainly involving blast-like cells, myocyte degeneration and large, irregularly shaped degenerate eosinophilic cells in the connective tissue. The herpesvirus was identified by negative staining TEM and real-time PCR. Sequencing of the C region and ORFs 42/43 confirmed that the variants met the definition of OsHV-1 μVar. We sequenced 30 other ORFs in twenty OsHV-1-positive individuals and compared them to the μVar specimens isolated between 2009 and 2011. The ORFs encoding putative membrane proteins showed the highest number of variations. Seven different genotypes were identified, confirming the presence of relevant genetic diversity. Phylogenetic analysis provided evidence for a well-separated μVar new group, with an evolutionary divergence estimated at 0.0013 from the other μVar variants. The geographical distribution of these newly described variants and their effective virulence should be investigated in future.

Sequential circulation of canine adenoviruses 1 and 2 in captive wild carnivores, France

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Two canine adenoviruses (CAdVs) were found to circulate sequentially in captive wild carnivores in France.

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CAdV-1 caused the death of a Eurasian wolf (Canis lupus lupus) with gross lesions and histopathological changes compatible with infectious canine hepatitis.

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CAdV-2 was subsequently found to circulate subclinically in other carnivores of the same zoological park.

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Analysis of the full-length genome of the wolf CAdV-1 strain showed a high genetic relatedness with an Italian strain detected in the same species.

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Future studies are needed to assess the CAdV ecology in endangered wild carnivores.

Scarce data are currently available about the ecology of canine adenoviruses (CAdVs) in wild carnivores. In this paper, the consecutive circulation of CAdV-1 and CAdV-2 in wild carnivores maintained in a French zoological park is reported. A fatal CAdV-1 infection was observed in a Eurasian wolf (Canis lupus lupus), which displayed gross lesions, histopathological changes and immunohistochemical findings suggestive of CAdV-1 infection. The virus was isolated on cell cultures and its genome was determined through next-generation sequencing, resulting genetically related to a recent Italian CAdV-1 strain detected in an Italian wolf. Subsequently, subclinical circulation of CAdV-2 was demonstrated by molecular methods in wild carnivores maintained in the same zoological park, some of which had been previously vaccinated with a CAdV-2 vaccine. Virus detection at a long distance from vaccination and by unvaccinated animals was suggestive of infection by a CAdV-2 field strain, although no data are available about the extent and duration of shedding of CAdV-2 modified-live virus in wild or domestic carnivores. The present paper provides new insights into the CAdV ecology in wildlife, although future studies are needed to fully understand the pathogenic potential of both CAdVs especially in endangered carnivore species.

First description of a mortality event in adult Pacific oysters in Italy associated with infection by a Tenacibaculum soleae strain

Summer mortality episodes in adult Pacific oysters have been described since the 1950s in various farming areas. Starting in 2012, a recrudescence of mortalities in commercial-sized oysters was first observed in France and then in Italy, with seasonality extension and translation later in the year. Moribund individuals collected during an event in Italy in December 2014 showed yellowish lesions of the mantle and adductor muscle. Histological examination revealed filamentous bacteria associated with necrotic areas. Quantitative PCRs targeting OsHV-1 and Vibrio aestuarianus detected only high loads of the pathogenic bacteria in tissues of symptomatic individuals. A lower diversity of the hemolymph microbiota was also evidenced in moribund individuals, with a predominance of Vibrio and Arcobacter species. A strain of Flavobacteriaceae was isolated from all the symptomatic individuals. Sequence analysis of the 16S rRNA gene identified the strain as Tenacibaculum soleae. When strain pathogenicity was tested by injection in adult individuals, it induced mortality rates of up to 45%, even in the absence of V. aestuarianus. As mortality occurred only 11 days post-infection, further investigation is needed to determine its effective virulence in natural conditions. This is the first description of a Tenacibaculum strain associated with bivalve mortalities.

Occlusive mycotic tracheobronchitis and systemic Alphaherpesvirus coinfection in a free-living striped dolphin Stenella coeruleoalba in Italy

A juvenile female striped dolphin Stenella coeruleoalba live stranded on 4 March 2016 at Alassio, western Ligurian Sea coast, Italy. The dolphin died shortly after stranding, and a complete postmortem examination was performed. Necropsy revealed severe tracheal occlusion and unilateral bronchial stenosis with luminal accumulation of abundant green-yellow mucous-gelatinous material. Histological features suggestive of tracheobronchial aspergillosis were observed. Cultures of lung tissue and tracheo-bronchial exudate isolated Aspergillus fumigatus, identified by a Microseq D2 LSUrDNA fungal sequencing kit. A pan-Herpesvirus nested-PCR assay on frozen samples obtained from multiple organs was positive. Phylogenetic analysis on the partial DNA polymerase gene revealed that the striped dolphin isolate was closely related to known cetacean Alphaherpesvirus sequences from the same host species. Attempted virus isolation was unsuccessful. The tissue levels of different persistent organic pollutants and the toxicological stress, evaluated using a theoretical model, showed a severely impaired immune response. This study reports the first case of occlusive mycotic tracheobronchitis in a free-living cetacean and the first molecular identification of an Alphaherpesvirus in a free-ranging striped dolphin stranded on the coast of Italy.

Canine adenovirus type 1 and Pasteurella pneumotropica co‑infection in a puppy

In 2008, a 2 months-old male German shepherd was presented with fever, depression, and evident organic wasting. The puppy died within 48 hours after the onset of clinical signs. A complete necropsy was performed. Bacteriological examination of samples from the brain, lung, liver, spleen, and bone marrow tested positive for Pasteurella pneumotropica. Histopathology demonstrated inflammatory and vascular lesions in the central nervous system and internal organs. Canine adenovirus type 1 nucleic acid was detected by polymerase chain reaction in the frozen brain but not in the formalin-fixed, paraffin-embedded liver and lung samples. The positive PCR was subsequently confirmed by indirect fluorescent antibody testing of the paraffin-embedded brain and liver sections. Although the liver is the primary site of viral damage, these laboratory findings suggest that Canine adenovirus type 1 infection should be included in the differential diagnosis of neuropathological diseases in dogs and that adenoviral infections could promote septicaemia caused by opportunistic pathogens.

A revisited hemolytic assay for palytoxin detection: Limitations for its quantitation in mussels

Palytoxin (PLTX) and its analogues have been detected as seafood contaminants associated with a series of human foodborne poisonings. Due to a number of fatalities ascribed to the ingestion of PLTX-contaminated marine organisms, the development of methods for its detection in seafood has been recommended by the European Food Safety Authority (EFSA). Due to its feasibility, the spectrophotometric hemolytic assay is widely used to detect PLTX in different matrices, even though a standardized protocol is still lacking. Thus, on the basis of available assay procedures, a new standardized protocol was set up using purified human erythrocytes exposed to PLTX (working range: 3.9 × 10(-10)-2.5 × 10(-8) M) in a K(+)-free phosphate buffered saline solution, employing a 5 h incubation at 41 °C. An intra-laboratory characterization demonstrated its sensitivity (limit of detection, LOD = 1.4 × 10(-10) M and quantitation, LOQ = 3.4 × 10(-10) M), accuracy (bias = -0.8%), repeatability (RSDr = 15% and 6% for intra- and inter-day repeatability, respectively) and specificity. However, the standardized method seems not to be suitable for PLTX quantitation in complex matrices, such as mussel (Mytilus galloprovincialis) extracts, at least below the limit suggested by EFSA (30 μg PLTXs/Kg shellfish meat). Thus, the hemolytic assay for PLTX quantitation in seafood should be used only after a careful evaluation of the specific matrix effects.

Meningoencephalitis and Listeria monocytogenes, Toxoplasma gondii and Brucella spp. coinfection in a dolphin in Italy

Listeria monocytogenes, Toxoplasma gondii and Brucella spp. can infect a wide range of species, including humans. In cetaceans, meningoencephalitis has been associated with T. gondii and Brucella spp. infection, whereas to our knowledge, L. monocytogenes infection has not previously been reported. Meningoencephalitis and L. monocytogenes, T. gondii and Brucella spp. were identified by means of both direct and indirect laboratory techniques in an adult female striped dolphin Stenella coeruleoalba found stranded in January 2015 on the Ligurian Sea coast, northwestern Italy. The animal was emaciated, and histopathology disclosed severe meningoencephalitis. The nature of the inflammatory response and intra-lesional protozoa were consistent with a mixed infection by L. monocytogenes, T. gondii and Brucella spp. We believe this is an unprecedented case of infection by 3 zoonotic pathogens and also the first bacteriologically confirmed case report of neurolisteriosis in cetaceans. Cerebral toxoplasmosis and neurobrucellosis may have led to the animal's disorientation and stranding, with L. monocytogenes having likely exacerbated the coinfection leading to the demise of this dolphin.

Confirmation of the progesterone receptor as an efficient marker of treatment with 17β-estradiol in veal calves

Under current European Union legislation the use of anabolic steroids in food-producing livestock is banned because of their long-term adverse effects on human health. We examined the expression profile of the immunohistochemical marker progesterone receptor in veal calves' sex accessory glands following experimental administration of anabolic compounds. The aim was to confirm the accuracy of the immunohistochemical approach in the detection of the over-expression of the progesterone receptor induced by the administration of sexual steroids at low levels (17β-estradiol and nandrolone alone or in combination). A total of 217 male veal calves were randomly divided into four groups: group A (104 calves) treated with 17β-estradiol (5 mg/head; 4 weekly injections); group B (20 calves) treated with nandrolone (50 mg/head; 4 weekly injections); group C (20 calves) treated with the association of the two steroids (5 mg estradiol + 50 mg nandrolone; 4 weekly injections); and group K (73 calves) kept as a control. All the sexual accessory glands were collected at the slaughterhouse (15 days after the last administration) and subjected to immunohistochemical staining with anti-progesterone receptor antibody. All the calves treated with 17β-estradiol alone or in association with nandrolone (groups A and C) showed strong positivity, while nandrolone-treated calves and controls (groups B and K) gave negative results to the immunohistochemical investigation. The statistical analysis showed that the progesterone receptor is a significant predictor of 17β-estradiol treatment alone or in association with nandrolone (p < 0.001): the immunohistochemical study resulted in 100% sensitivity (CI = 95%: 97.1-100%) and specificity (CI = 95%: 95.1-100%) for prostate and 99% sensitivity (CI = 95%: 95.6-100%) and 100% specificity (CI = 95%: 95.1-100%) for bulbo-urethral glands. The data confirm that this innovative biological approach offers a reliable tool to enhance the efficacy of the histological test to detect illegal treatments with estrogens alone or in association with androgens.

Molecular and histological characterization of bovine papillomavirus in North West Italy

Bovine papillomaviruses (BPVs) are group of worldwide-spread DNA virus that infect primarily cattle determining diseases of considerable economic relevance. Recently, research on BPVs, received a great impulse owing to the development of specific biomolecular analysis, mostly based on L1 gene sequencing, that resulted in the identification of new viral types. This work is aimed at the identification and molecular and histopathological characterization of BPVs circulating in North West Italy, one of the main national cattle breeding areas. In this study, 71 bioptic specimens were submitted both to histological examination and to PCR and sequencing analysis. Histopathology revealed various lesion types; however, no connections were demonstrated between involved viral types and histopathological findings. BPV DNA was demonstrated in all the analyzed samples and several viral types were detected. Particularly, molecular investigations revealed a broad diffusion of highly pathogenic BPV1 and 2 Deltapapillomavirus and presence of BPV3 and 9 Xipapillomavirus. Two cases of co-infection were also demonstrated. Phylogenetic analysis revealed presence of different clusters and therefore a noteworthy genetic variety among the analyzed viral types. This study provides information on the main BPVs types in North West Italy and our results demonstrate the complexity of viral epidemiology which is characterized by circulation of multiple viral types even inside single herds. Knowledge of the prevalence and of the variety of BPVs is a milestone for the development of appropriate prophylactic and therapeutic measures.

Sarcocystis Spp. Prevalence in Bovine Minced Meat: A Histological and Molecular Study

Sarcosporidiosis is caused by ingestion of contaminated raw or undercooked bovine meat and, although considered a minor zoonosis, it can represent a threath for immunocompromised people. Aim of this study was to determine the prevalence of Sarcocystis spp. in bovine minced meat intended for raw consumption collected from butcher shops and retail stores in Turin’s province (Piedmont region, Northwest Italy). Twenty-five samples were examined in parallel by histology and polymerase chain reaction (PCR). The prevalence of infestation of Sarcocystis spp. resulted to be 64% [confidence interval (CI) 95% 42-82] and 88% (CI 95% 69-97) respectively by histology and PCR. In detail, the prevalence resulted 80% for S. cruzi (CI 95% 59-93), 68% for S. hominis (CI 95% 46-85) and 4% for S. hirsuta (CI 95% 0.10-20). The high prevalence of S. hominis highlights that sarcosporidiosis may constitute a public health problem in Italy, particularly in regions like Piedmont, that has traditional dishes prepared from raw or undercooked bovine meat.

HoBi-like pestivirus experimental infection in pregnant ewes: Reproductive disorders and generation of persistently infected lambs

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HoBi-like pestivirus was administered to pregnant sheep.

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Infected animals displayed reproductive disorders.

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Persistently infected lambs were born that shed the virus through all body fluids.

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Sheep may serve as an alternative model for HoBi-like pestivirus vaccine studies.

In order to evaluate sheep as experimental model to test the efficacy of HoBi-like pestivirus vaccines for cattle, 10 sheep at different stages of pregnancy (30 or 50 days) were experimentally infected with the Italian prototype isolate Italy-1/10-1. Irrespective of the stage of pregnancy, virus inoculation resulted in reproductive failures, consisting of abortion, stillbirths or birth of weak or persistently infected (PI) lambs. Aborted fetuses, stillborn and dead lambs displayed extensive histopathological changes, consisting of hemorrhages, congestion and mononuclear infiltration in major organs. Pestiviral antigens were detected by immunohistochemistry in most tissues with remarkable signals in lungs and kidneys. PI lambs were constantly viremic, shed the virus through the nasal secretions and feces and, in all cases but one, did not have detectable HoBi-like pestivirus antibodies before the assumption of colostrum. The single seropositive infected lamb showed low-titer viremia and viral shedding that ceased only several weeks after the 3-month observation period. The study proves that sheep are susceptible to the reproduction failures caused by HoBi-like pestivirus infection and can serve as a suitable model for the evaluation of the fetal protection induced by homologous experimental vaccines.

First report of malignant catarrhal fever in a captive pudu (Pudu puda)

A male, six-year-old pudu (Pudu puda) from an Italian zoo was submitted for postmortem examination after sudden death. Necroscopy revealed non-suppurative bronchopneumonia and degeneration of the liver and haemorrhagic lesions of the thymus, pericardium and spleen. Microscopically, multifocal perivascular mononuclear cell infiltrates were observed in the kidneys, lungs, spleen, and the portal triads of the liver. Histological examination of the brain showed meningitis, vasculitis and perivascular cuffs of mononuclear inflammatory cells. A region of the DNA polymerase gene of malignant catarrhal fever viruses was amplified by real-time PCR and nested PCR. PCR products from the tissue samples were sequenced and analysed. The sequences showed 99% similarity with a portion of the caprine herpesvirus 2 DNA polymerase gene. This is the first report of malignant catarrhal fever in a captive pudu.

Granulomatous lesions in a wild mullet population from the eastern Ligurian Sea (Italy): mycobacteriosis vs. pseudotuberculosis

Mycobacterium spp. and Photobacterium damselae subsp. piscicida are recognized as the most frequent causative agents of granulomatous lesions in fish. Although frequent episodes of mycobacterial infections have been reported in wild fish worldwide, only sporadic cases have been documented to date in Italy. To investigate for the presence of lesions referable to mycobacteriosis and to identify the mycobacterial species involved, a total of 159 wild mullets were fished from the eastern coast of the Ligurian Sea, killed and necropsied. Liver and spleen samples were collected from all fish for histopathological and microbiological analyses. Molecular investigations for identification of Photobacterium damselae subsp. piscicida were performed. Gross examination revealed granulomatous lesions in one animal; microscopically, 42.14% of fish displayed granulomas with various histological features, 19.50% resulted positive at Ziehl-Neelsen staining, and were confirmed as mycobacterial lesions by culture. The identified colonies were characterized as M. fortuitum, M. abscessus, M. flavescens, M. chelonae, M. septicum and M. nonchromogenicum. In all, 35% of animals resulted positive for Photobacterium damselae subsp. piscicida. These data suggest widespread mycobacterial infection also by Photobacterium damselae subsp. piscicida infections in wild fish. Moreover, the pathogenicity of some mycobacterial species, previously considered as saprophytic, was demonstrated.

EU-approved rapid tests for bovine spongiform encephalopathy detect atypical forms: a study for their sensitivities

Since 2004 it become clear that atypical bovine spongiform encephalopthies (BSEs) exist in cattle. Whenever their detection has relied on active surveillance plans implemented in Europe since 2001 by rapid tests, the overall and inter-laboratory performance of these diagnostic systems in the detection of the atypical strains has not been studied thoroughly to date. To fill this gap, the present study reports on the analytical sensitivity of the EU-approved rapid tests for atypical L- and H-type and classical BSE in parallel. Each test was challenged with two dilution series, one created from a positive pool of the three BSE forms according to the EURL standard method of homogenate preparation (50% w/v) and the other as per the test kit manufacturer's instructions. Multilevel logistic models and simple logistic models with the rapid test as the only covariate were fitted for each BSE form analyzed as directed by the test manufacturer's dilution protocol. The same schemes, but excluding the BSE type, were then applied to compare test performance under the manufacturer's versus the water protocol. The IDEXX HerdChek ® BSE-scrapie short protocol test showed the highest sensitivity for all BSE forms. The IDEXX® HerdChek BSE-scrapie ultra short protocol, the Prionics®--Check WESTERN and the AJ Roboscreen® BetaPrion tests showed similar sensitivities, followed by the Roche® PrionScreen, the Bio-Rad® TeSeE™ SAP and the Prionics®--Check PrioSTRIP in descending order of analytical sensitivity. Despite these differences, the limit of detection of all seven rapid tests against the different classes of material set within a 2 log(10) range of the best-performing test, thus meeting the European Food Safety Authority requirement for BSE surveillance purposes. These findings indicate that not many atypical cases would have been missed surveillance since 2001 which is important for further epidemiological interpretations of the sporadic character of atypical forms.

Histology as a valid and reliable tool to differentiate fresh from frozen-thawed fish

Selling fish products as fresh when they have actually been frozen and thawed is a common fraudulent practice in seafood retailing. Unlike fish products frozen to protect them against degenerative changes during transportation and to extend the product's storage life, fish intended for raw consumption in European countries must be previously frozen at -20° C for at least 24 h to kill parasites. The aim of this study was to use histological analysis to distinguish between fresh and frozen-thawed fish and to evaluate this method for use as a routine screening technique in compliance with the requirements of European Commission Regulation No. 882/2004 on official food and feed controls. Method performance (i.e., accuracy and precision) was evaluated on tissue samples from three common Mediterranean fish species; the evaluation was subsequently extended to include samples from 35 fish species in a second experiment to test for method robustness. Method accuracy was tested by comparing histological results against a "gold standard" obtained from the analysis of frozen and unfrozen fish samples prepared for the study. Method precision was evaluated according to interrater agreement (i.e., three laboratories with expertise in histopathology in the first experiment and three expert analysts in the second experiment) by estimating Cohen's kappa (and corresponding 95 % confidence intervals) for each pair of laboratories and experts and the combined Cohen's kappa for all three experts and laboratories. The observed interrater agreement among the three laboratories and the three experts indicated high levels of method accuracy and precision (high sensitivity and specificity) and method reproducibility. Our results suggest that histology is a rapid, simple, and highly accurate method for distinguishing between fresh and frozen-thawed fish, regardless of the fish species analyzed.

A pantropic canine coronavirus genetically related to the prototype isolate CB/05

We report the genetic and biological characterisation of a novel pantropic canine coronavirus (CCoV), strain 450/07, which caused the death of a 60-day-old miniature pinscher. At the genetic level, this virus was strictly related to the prototype strain CB/05, but displayed some unique features. After experimental infection with the new pantropic isolate, most inoculated dogs showed diarrhoea and acute lymphopenia. Gross lesions and histological changes were mainly evident in the gut and lymphoid tissues, although some animals showed remarkable changed also in parenchymatous organs. The viral RNA was detected in the faeces and/or internal organs of most pups. These findings seem to indicate that strain 450/07 is able to spread to internal organs (mainly lymphoid tissues), causing lymphopenia but inducing a mild disease.