Canine mammary tumors (CMTs) share many features with human breast cancer (HBC), specifically concerning cancer-related pathways. Although the human epidermal growth factor receptor 2 (HER2) plays a significant role as a therapeutic and prognostic biomarker in HBC, its relevance in the pathogenesis and prognosis of CMT is still controversial. The aim of this study was to investigate HER2 expression in canine mammary hyperplasic and neoplastic tissues as well as to evaluate the specificity of the most commonly used polyclonal anti HER2 antibody by multiple molecular approaches. HER2 protein and RNA expression were determined by immunohistochemistry (IHC) and by quantitative real-time (qRT) PCR. A strong cell membrane associated with non-specific cytoplasmic staining was observed in 22% of carcinomas by IHC. Adenomas and carcinomas exhibited a significantly higher HER2 mRNA expression when compared to normal mammary glands, although no significant difference between benign and malignant tumors was noticed by qRT-PCR. The IHC results suggest a lack of specificity of the FDA-approved antibody in CMT samples as further demonstrated by Western immunoblotting (WB) and reverse phase protein arrays (RPPA). Furthemore, HER2 was not detected by mass spectrometry (MS) in a protein-expressing carcinoma at the IHC investigation. This study highlights that caution needs to be used when trying to translate from human to veterinary medicine information concerning cancer-related biomarkers and pathways. Further investigations are necessary to carefully assess the diagnostic and biological role specifically exerted by HER2 in CMTs and the use of canine mammary tumors as a model of HER2 over-expressing breast cancer.

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Canine mammary tumors (CMTs) represent a serious issue in worldwide veterinary practice and several risk factors are variably implicated in the biology of CMTs. The present study examines the relationship between risk factors and histological diagnosis of a large CMT dataset from three academic institutions by classical statistical analysis and supervised machine learning methods. Epidemiological, clinical, and histopathological data of 1866 CMTs were included. Dogs with malignant tumors were significantly older than dogs with benign tumors (9.6 versus 8.7 years, p < 0.001). Malignant tumors were significantly larger than benign counterparts (2.69 versus 1.7 cm, p < 0.001). Interestingly, 18% of malignant tumors were smaller than 1 cm in diameter, providing compelling evidence that the size of the tumor should be reconsidered during the assessment of the TNM-WHO clinical staging. The application of the logistic regression and the machine learning model identified the age and the tumor’s size as the best predictors with an overall diagnostic accuracy of 0.63, suggesting that these risk factors are sufficient but not exhaustive indicators of the malignancy of CMTs. This multicenter study increases the general knowledge of the main epidemiologica-clinical risk factors involved in the onset of CMTs and paves the way for further investigations of these factors in association with CMTs and in the application of machine learning technology.

Mycobacterium marinum is a slow-growing non-tuberculous mycobacterium, and it is considered the most common aetiologic agent of mycobacteriosis in wild and cultured fish. The diagnosis is principally made by histology when positive Ziehl-Neelsen stain granulomas are detected. The aim of this study was to investigate the occurrence of mycobacteriosis in extensively cultured Mugilidae of two lagoons (Cabras and San Teodoro) from Sardinia by the use of histology, microbiology, PCR and DNA sequencing. Nine of 106 mullets examined were affected by mycobacteriosis, and the spleen was the most affected organ. The histology detected higher rate (100%) of infection in spleen than the culture and PCR (75% and 62.5%, respectively). The sequencing of hsp65 gene identified M. marinum as the primary cause of mycobacteriosis in the mullets examined. Mullets affected by mycobacteriosis were mainly fished in the San Teodoro lagoon characterized by critical environmental conditions. Histology remains the most common method in detecting fish affected by mycobacteriosis, and PCR-based methods are essential for species identification. Our finding are worthy of attention because mycobacteriosis caused by M. marinum in reared mullets was evidenced for the first time in Sardinia, suggesting that this disease may be underestimated also in other cultured fish species.

The dusky grouper Epinephelus marginatus (Lowe) is an ecologically and commercially important fish species of the Atlantic and Mediterranean coastal rocky habitats. Despite records of didymozoid infections in several grouper species, the identification and pathogenesis of these parasites in E. marginatus are lacking. The aim of this study is to characterize the didymozoids of E. marginatus, particularly their mechanisms of infection and histopathological features. Dusky groupers (n = 205) were caught off Majorca Island (western Mediterranean Sea) and examined for parasites. Of the fish sampled, 45% were infected with white and yellow didymozoid capsules and brown nodules, found on the gills and pseudobranchs. Parasite abundance had a strong positive relationship with the fish length; only fish larger than 20 cm were infected, suggesting infection via consumption of an intermediate host, for which E. marginatus size was a limiting factor. The capsules contained two convoluted viable adult trematodes, identified as Didymodiclinus sp., in close contact with host capillary vessels, with no evidence of the tissue inflammatory response. Conversely, nodules containing degraded parasites were surrounded by an intense inflammatory infiltrate. The findings suggest that Didymodiclinus sp. have the potential to evade the host's immune system by inhibiting the inflammatory response.

The term intersex describes alterations in gonadal development with the simultaneous presence of male and female reproductive stages in the same gonad of a gonochoristic species. In coastal and estuarine environments, euryhaline fish living in polluted waters such as Mugilidae can frequently show these sexual anomalies. In this work, we analysed adult specimens of three species of euryhaline mullets (Chelon labrosus, Liza aurata and Mugil cephalus) from two Sardinian lagoons (Marcedd ı and San Teodoro) devoted to extensive aquacultural practices, in order to identify putative alterations in gonads and in gamete development. Overall, 13 of the 158 mullets examined (8.2%) were affected by gonadal disorders: four subjects (one C. labrosus, two L. aurata and one M. cephalus) exhibiting an intersex condition were found in the Marcedd ı lagoon and the other nine (five C. labrosus, two L. aurata and two M. cephalus) in the San Teodoro lagoon. Twelve of these gonads were classified as testis-ova (TOs) and one, belonging to a C. labrosus specimen, was a mixed gonadal tissue (MGT). Intersex condition was evaluated using an intersex index and all the recorded values showed a mild Ovotestis Severity Index (OSI). However, our findings suggest that fish gonadal disorders may be underestimated in extensive reared fish species, particularly in coastal brackish environments polluted by intensive agriculture and animal husbandry activities.

Canine leproid granuloma (CLG) is a mycobacterial cutaneous disease characterised by the presence of nodular skin lesions most commonly affecting the head and the dorsal aspect of the pinna (Malik and others 1998, Conceição and others 2011, Smits and others 2012). affected dogs appear otherwise healthy, and in the majority of cases the lesions tend to heal spontaneously over the course of weeks to months (Malik and others 1998). CLG has a wide distribution and was first reported in africa (Zimbabwe) in 1973. Since then, all published cases of CLG have originated in australia, new Zealand, Brazil or the USa (Malik and others 1998, Foley and others 2002, Conceição and others 2011, Smits and others 2012). To date, no case of this disease has been reported in europe.The mycobacterium responsible for CLG has not yet been isolated, but molecular investigations based either on 500 bp of the 16S rRna gene (Hughes and others 2000) or on the iTS1 region (Fyfe and others 2008) identified a mycobacterial species closely related to members of the Mycobacterium simiae clade in nodular skin lesions of dogs. This paper describes the clinical features of the first reported case of CLG in europe (to our knowledge), and the molecular investigation of the aetiological agent.a three-year-old female German shorthaired pointer was presented to the dermatology service of the internal Medicine Department at the University of Sassari for the evaluation of a skin nodule affecting the dorsal area of the right pinna. The skin lesion was previously treated with a topical therapy containing 1 per cent gentamycin (Gentalyn cream; Schering Plough Spa, Milan, italy) with no signs of improvement. The dog was housed with three other dogs and lived outside all year, received regular vaccination and treatment for parasites. The owner did not report any abnormalities regarding the general health and described an active dog that was performing perfectly during the hunting season. also, the animal never travelled outside Sardinia/italy.On general physical examination the dog did not show any abnormalities. On dermatological examination a 2 cm alopecic, slightly ulcerated cutaneous nodule was detected on the dorsal aspect of the right pinna (Fig 1a). as differential diagnoses the following were considered: neoplasia (histiocytoma and mast cell tumours), cutaneous leishmaniasis, an infectious (fungi, bacteria) granulomatous lesion and canine sterile pyogranuloma syndrome. Skin scrapings and hair plucks collected at the periphery of the lesion were negative for parasites and for fungal spores or hyphae.Cytological samples were obtained by fine needle aspiration of the skin nodule and stained with a modified Wright/Giemsa stain (Dip Quick Stain Kit; Dyaset S.r.l., Portomaggiore, italy). Microscopic examination revealed the presence of inflammatory cells composed mainly of macrophages, few degenerated neutrophils and small lymphocytes. The macrophages showed phagocytised, negatively staining, rod-shaped bacteria. Thus, a mycobacterial infection was suspected...

Consumer preference for healthy and sustainable food products has been steadily increasing in recent years. Bivalve mollusks satisfy these characteristics and have captured ever-increasing market shares. However, the expansion of molluscan culture in worldwide and global trade have favored the spread of pathogens around the world. Combined with environmental changes and intensive production systems this has contributed to the occurrence of mass mortality episodes, thus posing a threat to the production of different species, including the Pacific oyster Crassotrea gigas. In the San Teodoro lagoon, one of the most devoted lagoons to extensive Pacific oyster aquaculture in Sardinia, a mortality outbreak was observed with an estimated 80% final loss of animal production. A study combining cultural, biomolecular and histopathological methods was conducted: (1) to investigate the presence of different Vibrio species and OsHV-1 in selected oyster tissues (digestive gland, gills, and mantle); (2) to quantify Vibrio aestuarianus and to evaluate the severity of hemocyte infiltration in infected tissues; (3) to produce post-amplification data and evaluating ToxR gene as a target for phylogenetic analyses. Results provide new insights into V. aestuarianus infection related to oyster mortality outbreaks and pave the way to the development of tools for oyster management.