The study of histopathological changes caused by influenza A (H5N8) viral infection in bird species is essential for the understanding of their role in the spread of this highly infectious virus. However, there are few such studies under natural conditions in minor gallinaceous species. This article describes the pathomorphological findings in Colchis pheasants infected naturally with H5N8 during an epizootic outbreak in Bulgaria. Samples of internal organs of 10 carcasses were collected for histopathological and immunohistochemical evaluation, virus isolation and identification, and nucleic acid detection. Consistent macroscopic findings were lesions affecting the intestine, heart, lung, and pancreas. Congestion and mononuclear infiltrate were common findings in the small intestine, as were necrosis and lymphoid clusters in the lamina propria of the caeca. Congestion with small focal necrosis and gliosis with multifocal nonpurulent encephalitis were observed in the brain. Myocardial interstitial oedema and degenerative necrobiotic processes were also detected. Immunohistological analysis confirmed systemic infection and revealed influenza virus nucleoprotein in all analysed organs. Variable necrosis was observed in the brain, liver, trachea, heart, small intestine, and caeca. Viral antigen was commonly found in the brain, heart, lung and trachea. Contact with migrating waterfowls was suspected as a reason for the outbreak.

The aim of the study was to describe the process of neuron death in the cerebral cortex caused by embryonic carbofuran exposure. 81 mouse foetuses from 27 breeding mice were used in the study. Carbofuran was administered by gavage from the 6ᵗʰ to the 15ᵗʰ day of gestation to two groups: one at 0.0208 and the other at 0.0417 mg/kg b.w. On the 17ᵗʰ day, the mice were sacrificed and the foetuses were taken to measure the ROS (malondialdehyde/MDA and superoxide dismutase/SOD) activity in brain tissue, the number of apoptotic embryonic cerebral cortex neurons using a TUNEL assay, and necrotic cells using HE staining. Examination of p53 and caspase 3 expression was done by immunohistochemistry. Data were analysed using analysis of variance (ANOVA) and Duncan’s test. Increased activity of cerebral ROS characterised by significant elevation of the MDA level (P < 0.05), decreased SOD (P < 0.01), increased p53 and caspase 3 expression, and cerebral cortical neuron death either by necrosis or apoptosis (P < 0.05) were found. At the low dose carbofuran increased expression of p53, caspase 3, and apoptosis. At the high dose it increased levels of MDA and necrosis. Increased expression of p53 and caspase 3 and apoptosis indicated that carbofuran may cause apoptosis through the intrinsic pathway. The increased apoptosis grants an opportunity to prevent and treat the effect of ROS due to gestational carbofuran exposure.

In veterinary medicine, sensitive and specific markers of the early stages of renal failure still remain to be established. Podocytes could be a promising diagnostic tool in veterinary nephrology, especially in the differentiation of active pathological disease and glomerulopathies. Podocin is one of the robust proteins exploitable in detection of podocyturia. This article presents podocyte detection in urine for diagnostic purposes in veterinary medicine using a variety of methods. We describe the advantages and disadvantages of the immunohistochemical technique currently used, and of scanning microscopy, chromatography, and immunostaining. The identification of podocin-positive cells is a promising diagnostic tool in the detection of the early stages of glomerular basement membrane damage. The detection of renal failure prior to the occurrence of azotaemia is of high clinical importance from the clinical and scientific points of view.

OBJECTIVE To establish reference limits for hepatic bile duct-to-arteriole ratio (BD:A) and bile duct-to-portal tract ratio (BD:PT) in healthy cats and assess whether these parameters could be used to support a diagnosis of biliary ductopenia in cats. SAMPLE Hepatic biopsy samples from healthy cats (n = 20) and cats with ductopenia (2). PROCEDURES Hepatic biopsy samples from healthy cats were used to count the number of bile ducts and hepatic arterioles in 20 portal tracts for each cat. Mean BD:A and mean BD:PT for each cat were calculated, and these values were used to determine reference limits for mean BD:A and mean BD:PT. Results of histologic evaluation, including immunohistochemical staining in some instances, were compared for healthy cats versus cats with ductopenia. RESULTS Of the 400 portal tracts from healthy cats, 382 (95.5%) and 396 (99.0%) had BD:A and BD:PT, respectively, ≥ 1.0, with less variability in BD:A. Mean BD:A and BD:PT were markedly lower in both cats with ductopenia, compared with values for healthy cats. However, only mean BD:A for cats with ductopenia was below the reference limit of 0.59. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that systematic evaluation of BD:A, with a lower reference limit of 0.59 to define biliary ductopenia in cats, may be a discrete and easily applied morphometric tool to enhance detection of ductopenia in cats. However, application of this ratio required evaluation of ≥ 20 portal tracts with cross-sectioned portal elements to determine a mean BD:A value.

OBJECTIVE To investigate luteinizing hormone (LH) receptor expression in canine nonneoplastic and neoplastic lymph nodes, circulating nonneoplastic lymphocytes, and T-cell lymphoma (TCL) cell lines. SAMPLE Formalin-fixed, paraffin-embedded lymph nodes (5 neoplastic and 3 nonneoplastic) from 6 dogs, circulating lymphocytes from venous blood specimens obtained from 12 healthy dogs, and 3 TCL cell lines derived from 3 dogs with primary lymphoma. PROCEDURES Lymph node specimens were immunohistochemically stained for determination of LH receptor expression. Circulating nonneoplastic lymphocytes and TCL cell lines were evaluated for LH receptor expression by use of flow cytometry; circulating lymphocytes were also immunophenotyped. The mean percentage of cells positive for LH receptors was determined for each type of specimen. For the healthy dogs, percentages of circulating B and T lymphocytes that expressed LH receptors were assessed on the basis of sex and reproductive status. RESULTS The mean percentage of LH receptor-positive cells in canine neoplastic and nonneoplastic lymph nodes was 12.4% and 4.1%, respectively. For the healthy dogs, the mean percentage of circulating LH receptor-positive T lymphocytes was significantly higher in gonadectomized dogs (16.6%) than in sexually intact dogs (10.5%); the percentages of circulating LH receptor-positive B lymphocytes did not significantly differ by reproductive status. Among the 3 canine TCL cell lines, LH receptor expression ranged from 10% to 45%. CONCLUSIONS AND CLINICAL RELEVANCE In this study, LH receptor expression by canine neoplastic and nonneoplastic lymphocytes was detected. Research into the effects of downregulation of LH receptor activation in dogs with lymphoma is warranted.