Relationship between chicken proventricular necrosis virus prevalence and transmissible viral proventriculitis in broiler chickens in Poland.

Transmissible Viral Proventriculitis (TVP) is a disease of chickens which contributes to significant production losses. Recent reports indicate the role of chicken proventricular necrosis virus (CPNV) in the development of TVP. However, the relationship between CPNV and TVP is inconclusive and it has been addressed in just a few reports. Given the above, a study was conducted to identify the relationship between TVP and CPNV prevalence in broiler chickens in Poland. The study was carried out on 35 proventriculi samples sent for histopathological (HP) examination to the Faculty of Veterinary Medicine in Olsztyn between 2017 and 2019. After HP examination, TVP positive samples were processed for CPNV identification by RT-PCR. TVP was the most common pathological condition of proventriculi (23 cases). CPNV was identified in 10 out of those 23 cases. The average HP score, and the average necrosis and infiltration score for CPNV-positive samples was significantly higher than in CPNV-negative ones. The average age of the CPNV-positive chickens was significantly lower than in CPNV-negative birds. Our study confirms the role of CPNV in TVP pathogenesis and it seems that preservation of the proventriculi in the early stages of the disease, when the lesions are more pronounced, should result in a greater probability of CPNV detection.

Intraocular Chondrosarcoma in a Rabbit.

Post-traumatic intraocular sarcomas are rarely reported in domestic animals and are most common in cats. An 8-year-old rabbit (Oryctolagus cuniculus) was referred to a veterinary clinic due to ocular discharge, uveitis and protein precipitate in the anterior chamber of the right eye. The eye was enucleated and histopathological examination revealed a poorly demarcated tumour within the ciliary body with invasion to adjacent eye structures. Neoplastic cells formed chaotic cartilage lacunae and were immunopositive for vimentin but immunonegative for pancytokeratin. On this basis, the neoplasm was diagnosed as a chondrosarcoma. To the best of our knowledge, this is the first report of intraocular chondrosarcoma in a rabbit. There was no history of previous ocular trauma but as there was serological evidence of Encephalitozoon cuniculi infection, inflammation could have been a predisposing factor to development of the neoplasm.

Canine and Feline Oral Cavity Tumours and Tumour-like Lesions: a Retrospective Study of 486 Cases (2015-2017).

Oral cavity tumours and tumour-like lesions are common in dogs and cats, and their diagnosis and classification requires histopathological examination. The aim of this study was to analyse retrospectively oral cavity lesions in dogs and cats in order to evaluate the distribution of inflammatory, hyperplastic and neoplastic lesions manifested as tumours. A total of 486 oral cavity tumours and tumour-like lesions (340 canine; 146 feline), diagnosed routinely from 2015 to 2017, were included. The lesions were classified as inflammatory, hyperplastic or neoplastic (benign and malignant). Histopathological diagnosis was based on haematoxylin and eosin staining and, when necessary, May-Grünwald-Giemsa (for mast cell tumours) or Masson's Fontana (for melanomas) stains or immunohistochemistry (for CD3, CD79α and S100 markers). For dogs, 29.11% (99/340) of the lesions were benign tumours, 24.12% (82/340) were hyperplastic lesions and 14.7% (50/340) were inflammatory lesions. For cats, 4.79% (7/146) were benign tumours, 15.07% (22/146) were hyperplastic lesions and 57.53% (84/146) were inflammatory lesions. Furthermore, 23.24% (79/340) of canine cases were diagnosed with gingival hyperplasia and 19.12% (65/340) were diagnosed with peripheral odontogenic fibroma, while 43.84% (64/146) of feline cases were diagnosed with chronic lymphoplasmacytic stomatitis. Malignant tumours in dogs and cats constituted 32.06% (109/340) and 21.91% (32/146) of the lesions, respectively, with high-grade melanoma in dogs and squamous cell carcinoma in cats being the most common.

Identification of Transmissible Viral Proventriculitis (TVP) in broiler chickens in Poland.

The aim of the study was to investigate the possibility of Transmissible Viral Proventriculitis (TVP) occurrence in broiler chickens in Poland. In march 2016 proventriculi samples were collected from broiler chickens showing poor uniformity and decreased body weight, accompanied by enlarged proventriculi. Histopathological examination of affected proventriculi revealed typical lesions associated with TVP (vacuolar degeneration and necrosis of glandular epithelium, replacement of glandular epithelium by hyperplastic ductal epithelium and moderate to severe lymphocytic infiltration). To our best knowledge, up to date there is no report indicating the presence of TVP in Poland nor in Central and Eastern Europe.

Morphology and immunoreactivity of canine and feline extramedullary plasmacytomas.

The aim of the study was the evaluation of morphology and immunophenotype of canine (19 cases) and feline (7 cases) extramedullary plasmacytomas. Tumours, located in skin, oral cavity and spleen were surgically excised, fixed and processed for histopathology and immunohistochemistry (CD79α, CD18, proliferating cell nuclear antigen, metallothionein). Histologically, tumours were classified into mature, cleaved, asynchronous, polymorphous blastic, hyalin, or monomorphous blastic type. All evaluated tumours showed cytoplasmic expression of CD79α antigen. The expression of CD18 was observed in canine cutaneous and splenic tumours. In canine tumours expression of metallothionein was low to moderate, while in feline plasmacytomas - absent or low. In canine tumours, the mitotic index and proliferating cell nuclear antigen index were positively correlated with the expression of metallothionein. In feline tumours no correlation between mitotic index, proliferating cell nuclear antigen and metallothionein was found. This is the first study describing expression of metallothionein in canine and feline extramedullary plasmacytoma.

Effect of low-energy laser irradiation and antioxidant supplementation on cell apoptosis during skeletal muscle post-injury regeneration in pigs.

The aim of this study was to evaluate the effect of low-energy laser irradiation, coenzyme Q10 and vitamin E supplementation on the apoptosis of macrophages and muscle precursor cells during skeletal muscle regeneration after bupivacaine-induced injury. The experiment was conducted on 75 gilts, divided into 5 experimental groups: I--control, II--low-energy laser irradiation, III--coenzyme Q10, IV--coenzyme Q10 and vitamin E, V--vitamin E. Muscle necrosis was induced by injection of 0.5% bupivacaine hydrochloride. The animals were euthanized on subsequent days after injury. Samples were formalin fixed and processed routinely for histopathology. Apoptosis was detected using the TUNEL method. The obtained results indicate that low-energy laser irradiation has a beneficial effect on macrophages and muscle precursor cell activity during muscle post-injury regeneration and protects these cells against apoptosis. Vitamin E has a slightly lower protective effect, limited mainly to the macrophages. Coenzyme Q10 co-supplemented with vitamin E increases the activity of macrophages and muscle precursor cells, myotube and young muscle formation. Importantly, muscle precursor cells seem to be more sensitive to apoptosis than macrophages in the environment of regenerating damaged muscle.

Aggressive, solid variant of alveolar rhabdomyosarcoma with cutaneous involvement in a juvenile labrador retriever.

An 8.5-month-old male Labrador retriever presented with a cutaneous mass in the right maxillofacial region and swelling of the gingiva. The dog received antibiotic and anti-inflammatory treatment. After 3 weeks the dog returned, presenting with disseminated cutaneous tumours on the neck, trunk and groin. One of the nodules was resected and a cutaneous round cell tumour was diagnosed on microscopical examination. The dog was humanely destroyed. Necropsy examination revealed disseminated tumours in the skin, internal organs and skeletal muscles. Microscopically, all of the tumours were composed of small round cells, arranged in nests. Immunohistochemically, the neoplastic cells expressed vimentin, desmin, MyoD1, myogenin and smooth muscle actin, but were negative for CD3, CD18, CD79αcy, cytokeratin AE1/AE3, chromogranin A, class II molecules of the major histocompatibility complex, neuron-specific enolase and S100. The average Ki67 index was 89.5%. The final diagnosis was a solid variant of alveolar rhabdomyosarcoma (ARMS). This is the first report of the cutaneous multifocal form of ARMS in veterinary oncology.

Cytomorphometry of canine cutaneous histiocytoma.

A morphometric analysis of tumoral Langerhans cells and activated macrophages was conducted using canine cutaneous tumors (65 cases of canine cutaneous histiocytoma and 7 cases of pyogranuloma). The histiocytic origin of the tumor cells was confirmed using immunohistochemistry. The parameters of the morphometric analysis included cellular and nuclear size and shape and the nuclear:cytoplasmic ratio; the variability of these features was calculated separately for each tumor. The canine cutaneous histiocytoma group was divided into four stages of regression depending on the intensity of the lymphocytic infiltration. Statistical analysis revealed that the anisocytosis, anisokaryosis and cellular pleomorphism of tumoral Langerhans cells increased, while the cellular circularity and nuclear:cytoplasmic ratio decreased with tumor regression. Activated macrophages of the pyogranuloma were significantly larger, and had larger nuclei, than tumoral Langerhans cells. Furthermore, these activated macrophages showed greater anisocytosis and anisokaryosis and a lower nuclear:cytoplasmic ratio than tumoral Langerhans cells in the first stages of tumor regression. These results indicate that tumoral Langerhans cells undergo morphologic changes during the regression of canine cutaneous histiocytoma, reflecting their maturation and differentiation. Morphometry can be a useful method for distinguishing activated macrophages from tumoral Langerhans cells.

Fibromuscular dysplasia in arteries and in a vein in broiler chickens.

Fibromuscular dysplasia (FMD) is a group of nonatherosclerotic, noninflammatory diseases of blood vessels with unknown aetiology. In our study, FMD was diagnosed in blood vessels in samples taken from kidneys, liver and lung of broiler chickens. The FMD occurred during rearing in 8 of 108 broiler chickens examined for the effects of intensive rearing on the.internal organs. Histopathological and immunohistochemical examinations revealed medial subtypes of FMD, medial fibromuscular dysplasia and medial fibromuscular stenosis. The first subtype presented as plugs in vessel lumens consisting of smooth muscle and fibrous connective tissue originating from the tunica media. The second subtype presented as a proliferation of smooth muscle cells and fibroblasts originating from the media and leading to lumen stenosis. The aetiology of FMD is still unknown. Thus, genetic factors are suspected as a cause of the disease. This is the first report of FMD in a vein of an animal species.

Veterinary pathology in Europe in the light of the congresses of the European Society of Veterinary Pathology in the last decade.

This paper presents the main trends in the activity of European veterinary pathologists in the context of their oral presentations (plenary lectures and short presentations) and posters provided during annual meetings of the European Society of Veterinary Pathology (ESVP), in the decade 1997-2006. It was found that the issue that was most often brought up in the meetings was organ pathology (566 presentations). Infectious and parasitical diseases were only slightly less frequent (548 presentations). Oncology was another common issue (404 presentations). During this decade, 52 plenary lectures were presented, 765 oral presentations and 1 072 posters. Altogether, 1 889 presentations were made, which is between 127 and 238 per year. Research by Polish scientists accounted for 3.16% of all presentations. Additionally, the subject matter discussed at the annual meetings is analysed, and the trends in the development of veterinary diagnostic pathology and broad pathology education are indicated. It is shown that veterinary pathology enhances knowledge in the field of veterinary medicine by fulfilling a cognitive and diagnostic role.