SummaryThe present report describes a case of cutaneous papillomatosis related to equine papillomavirus type 2 (EcPV2) with concomitant cutaneous habronemiasis. A 2‐year‐old female Pura Raza Española horse was referred for a dermatological evaluation because of the onset of cutaneous multifocal, nodular lesions on the face characterised by a warty and partially ulcerated overlying epidermis. Multiple biopsies were taken from these lesions, and cutaneous viral papillomas with a concomitant severe focal eosinophilic dermatitis with intralesional Habronematidae nematode larvae were diagnosed. Immunohistochemistry revealed papillomaviral capsid protein L1 in the epidermal proliferative lesion, confirming the presence of a productive infection. Rt‐qPCR confirmed the presence of EcPV type 2. To the authors’ knowledge, this is the first report of EcPV2‐related papillomas with concurrent habronemiasis.

The study of the immune response in several types of tumors has been rapidly increasing in recent years with the dual aim of understanding the relationship between neoplastic and immune cells as well as identifying targets for cancer immunotherapy. Despite being considered one of the most immunogenic tumor types, melanoma can progress in the presence of abundant lymphocytic infiltration, therefore suggesting that the immune response is not able to efficiently control tumor growth. The purpose of this study was to investigate whether the density, distribution and grade of tumor-infiltrating lymphocytes (TILs) in 97 canine melanocytic tumors is associated with histologic indicators of malignancy and can be considered a prognostic factor in the dog. As a further step in the characterization of the immune response in melanocytic tumors, an immunohistochemical investigation was performed to evaluate the two main populations of TILs, T-lymphocytes (CD3 + ) and B-lymphocytes (CD20 + ). The results of our study show that TILs are present in a large proportion of canine melanocytic tumors, especially in oral melanomas, and that, differently from humans, the infiltrate is usually mild. The quantity of CD20 + TILs was significantly associated with some histologic prognostic factors, such as the mitotic count, the cellular pleomorphism and the percentage of pigmented cells. Remarkably, a high infiltration of CD20 + TILs was associated with tumor-related death, presence of metastasis/recurrence, shorter overall and disease-free survival, increased hazard of death and of developing recurrence/metastasis, hence representing a potential new negative prognostic factor in canine melanocytic tumors. a commercially available rabbit antibody against CD20 and a rabbit polyclonal antibody against CD3 (1:200; 0452; were used. Antigen retrieval was achieved in a preheated Tris-EDTA buffer solution (pH 9.0) for the CD3 antibody, while no antigen retrieval was performed for the CD20 antibody. Endogenous peroxidases were blocked using 3% H 2 O 2 for 5 minutes at room temperature and protein block performed with a commercially available kit (ab93677; Abcam, Cambridge, UK). Slides were incubated with primary antibodies for 1 hour in a humidified chamber at room temperature. Afterwards they were incubated with an ABC ready-to-use kit (ab93677; Abcam, Cambridge, UK) following the manufacturer’s instructions. Positive reaction was revealed with 3-amino-9-ethilcarbazole (Dako, Glostrup, Denmark). Carazzi’s hematoxylin was used as a counterstain. Coverslips were mounted with Faramount Mounting Medium (Dako, Glostrup, Denmark). Normal canine lymph node was used as positive control. Negative controls were performed omitting the primary antibody and incubating tissue sections with Tris–phosphate-buffered saline buffer. Only TILs defined according to Clark et al. and Clemente et al. this study (CD3 + or CD20 + TILs).

An abortion outbreak occurred in a goat herd of Murciano-Granadina breed in Almeria Region in Spain where 80 pregnant females aborted. All bacteriological and parasitological examinations resulted negative, whereas virological investigations and real-time PCR assay showed the presence of Caprine alphaherpesvirus 1 DNA in the pathological specimens from aborted foetuses. Nucleotide sequence analysis revealed that the DNA was highly close related to the Swiss strain E-CH (99.7%) and a little less extent to the Italian BA.1 strain (99.4%). Histopathological examination revealed multifocal, well-circumscribed, 50- to 200-μm-diameter foci of coagulative necrosis in the liver, lungs and kidneys of three foetuses. In the periphery of the necrosis, there were frequently epithelial cells with the chromatin emarginated by large, round, amphophilic intranuclear viral inclusion bodies. The source of the infection in the herd could not clearly find out even some hypothesis were formulated. This seems to be the first report of an abortion outbreak due to Caprine alphaherpesvirus 1 in a goat herd in Spain.

A 14-year-old female spayed Dachshund was presented with generalized scaling, erythema, pruritus, poor quality of hair coat, and progressive weight loss. Cutaneous epitheliotropic T-cell lymphoma (CETCL) was suspected. Skin biopsies were suggestive of CETCL. However, immunohistochemistry revealed the presence of numerous CD20+ and CD3+ cells. Clonality assay demonstrated a clonal T-cell receptor gamma rearrangement and a polyclonal IgH gene rearrangement. Double-label immunofluorescence confirmed coexpression of CD3 and CD20 by neoplastic cells. By double immunohistochemistry, neoplastic cells were CD3+ and PAX5-. The results are compatible with a CD3+, CD20+ CETCL. Coexpression of CD20 and CD3 has been recognized in peripheral T-cell lymphomas. Although documented in human CETCL, it has not been reported in canine CETCL. The pathogenetic basis of CD20 expression in mycosis fungoides is explored.

Feline injection-site sarcoma (FISS) is an aggressive tumor believed to arise from the proliferation of fibroblasts and myofibroblasts in areas of chronic inflammation, particularly at sites of injection. Local recurrence is frequent after surgical excision. Gelatinases (MMP-2 and MMP-9) and their inhibitor (TIMP-2) are endopeptidases pivotal in extracellular matrix remodeling and therefore in tumor invasiveness. The aim of this study was to investigate the immunohistochemical expression of MMP-2, MMP-9, and TIMP-2 in FISS to assess their usefulness as prognostic factors. Size, soft tissue sarcoma (STS) grading system, depth of infiltration, surgical margins, and Ki-67 index were evaluated as additional prognostic markers. Twenty-four cases of primary FISS were classified according to clinical follow-up as nonrecurrent (NR, n = 14; 58.3%) and recurrent (R, n = 10; 41.7%). MMP-2, MMP-9, and TIMP-2 were variably expressed in the FISS examined, confirming their role in tumor invasiveness, yet they did not show significant differences between the R and NR groups. These results could be due to different tumor stages or to the multiple activities of these enzymes, not limited to ECM remodeling. The immunohistochemical expression of these enzymes considered alone does not seem to be useful as a prognostic marker. STS grading system, depth of infiltration, surgical margins, and Ki-67 index did not relate to recurrence. Instead, the size of the tumor, measured after formalin fixation, with an optimal cutoff of 3.75 cm (accuracy = 86%; P < .05), and the mitotic count, with an optimal cutoff of 20 mitoses/10 HPF (accuracy = 80%; P < .05), could be evaluated as useful prognostic markers.

This report describes a case of spontaneous fibroblastic osteosarcoma in the humerus of a lion from a private park in Perugia, Italy. The tumor had an irregular, smooth, brown surface and a generally firm, rubbery consistence with gritty to hard areas interspersed. The mass was poorly vascularized with areas of necrosis at the periphery. The cut surface showed a multilobulated mass that had breached the humeral cortex, with periosteal production of reactive bone. The mass invaded the epiphysis, the synovial membrane, the joint capsule and ligaments. A mild hemorrhagic effusion appeared in the joint space. Clinical signs, gross and histopathologic findings are described in this rare case of a malignant bone tumor.

The benefits of linseed administration on acidic composition of animal products are well known. The aim of this work was to study the effects on liver morphology induced by a prolonged administration of linseed enriched diets. Sixty multiparous ewes were divided into 3 groups of 20 animals each. Groups received alfalfa hay as forage and three different concentrate diets: a control diet (CTR) without linseed and two diets supplemented with different levels (10 and 20% as fed, LE-10 and LE-20, respectively) of ground and extruded linseed. Liver samples were collected 80 days post-partum from 9 animals per group. The placement of biopsy needle was monitored by ultrasound visualization. The liver specimens were fixed and embedded with paraffin; serial sections were cut and stained with haematoxylin-eosin. The most characteristic finding observed in all but one biopsies coming from group CTR and LE-10 was represented by a diffuse and severe hydropic-vacuolar cell degeneration (no differences were observed amongst the two groups); cell damage in group LE-20 appeared to be lower. No lipid degeneration was virtually detectable in any of the samples; only in one animal from group CTR a moderate steatosis was observed. Our results suggested that prolonged administration of extruded linseed diets during the peripartum period does not adversely affect liver function in lactating ewes.