Equine acquired multiple acyl-CoA dehydrogenase deficiency (MADD) in 14 horses associated with ingestion of Maple leaves (Acer pseudoplatanus) covered with European tar spot (Rhytisma acerinum).

This case-series describes fourteen horses suspected of equine acquired multiple acyl-CoA dehydrogenase deficiency (MADD) also known as atypical myopathy of which seven cases were confirmed biochemically with all horses having had access to leaves of the Maple tree (Acer pseudoplatanus) covered with European tar spot (Rhytisma acerinum). Assessment of organic acids, glycine conjugates, and acylcarnitines in urine was regarded as gold standard in the biochemical diagnosis of equine acquired multiple acyl-CoA dehydrogenase deficiency.

Evaluation of goose serum amyloid a acute phase response by enzyme-linked immunosorbent assay.

Serum amyloid A (SAA) is of interest as the circulating precursor of amyloid A protein, the fibrillar component of AA (secondary) amyloid deposits, and also as an extremely sensitive and rapid major acute phase protein. Serum concentrations of acute phase proteins (APPs) provide valuable information about the diagnosis and prognosis of various diseases, and thus the relevance of APPs for monitoring the health status of domestic animals is widely accepted. More importantly, the measurement of SAA concentration assists in assessing the prognosis in secondary amyloidosis, which is a common disease of geese, affecting an increasing number of animals. In the present study we introduce a highly sensitive goose-specific ELISA method for measuring SAA concentration in goose serum or plasma samples. Samples were taken from geese of the Landes Grey and Hungarian White breeds, which were stimulated for an acute phase reaction by administration of a commercially available fowl cholera vaccine containing inactivated Pasteurella multocida. Strong and characteristically rapid acute phase responses were measured in both breeds, peaking at approximately 24 h after inoculation. The maximum SAA concentration was 1200 microg/ml. At 72 h postinoculation, the concentrations returned to pre-inoculation values. There was significantly (p = 0.004) less intense response in the control groups; however, a very mild increase of SAA levels was detected due to the stress inevitably caused by the sampling procedure.

Necrotizing granulomatous hepatitis in slaughtered broilers.

The present study describes a subclinical necrotizing granulomatous hepatitis in normal broilers routinely slaughtered in a medium-sized (72,000 birds per day) abattoir in the Netherlands. An exploratory investigation was scheduled on line during 20-min periods for 82 flocks (3000 birds examined per period). Liver and duodenum samples were collected for histopathology from 365 birds with liver pathology. Bacteriology was performed from 240 livers with lesions and 80 control livers. In addition to the hepatic pathology, other gross lesions of the carcasses, such as footpad dermatitis and broken legs/wings, were noted. The average prevalence for gross liver lesions was 0.16% (ranging from 0% to 0.63% per flock); 89.59% of the livers were enlarged, had a firm consistency, and revealed multifocal necrotic spots. Microscopically, 51.66% showed a granulomatous reaction in addition to the necrosis. There was no consistent anaerobic or aerobic bacterial growth in comparison to normal livers. A large proportion of the livers revealed growth of Escherichia coli, Bacteroides spp., Lactobacillus spp., Staphylococcus spp., and Streptococcus spp., and this was often with more than one type of bacterial colony. The duodenum mucosa grossly showed some redness with a mucous mass on its surface. Microscopically (n = 176) in 5.70% there were no changes in anatomy and cellular activities; 64.20% had a mildly increased number of lymphoid cells and heterophils in the lamina propria and between villus epithelial cells. The remaining 30.10% had moderate degenerative changes of villus epithelium with a mixed cellular infiltration in the lamina propria; 23.29% of the duodenum samples contained coccidia (infestation stage: mild to moderate). Signs of overgrowth with Clostridium spp. were not observed. There was a small, but significant correlation (rs = 0.30; P = 0.006) between prevalence of liver pathology and footpad dermatitis.

Immunohistochemical expression of tenascin in melanocytic tumours of dogs.

The aim of this study was to investigate tenascin-C (TN) immunolabelling and labelling for endothelium by von Willebrand Factor (vWF) in melanocytic tumours of dogs as compared with normal tissues, to evaluate the TN distribution in these types of tumours and to investigate whether a relation could be established between TN and angiogenesis in different types of tumour. Samples of normal dog skin (n=8), benign skin melanocytomas (n=10), malignant oral melanomas (n=9) and malignant toe melanomas (n=5) were studied. The percentages of TN and vWF immunolabelling per total microscopical area were analysed by morphometric methods. In normal skin, TN was found at dermo-epidermal junctions, around hair follicles, in the smooth muscles of hair follicles, and in the walls of blood vessels. TN immunolabelling (distribution and intensity) in melanocytomas was comparable with that found in normal skin. In melanomas, TN expression was considerably increased, its intensity in toe melanomas being twice that observed in oral melanomas. The degree of TN immunolabelling was not related to the histological malignancy of the melanomas. In melanomas, TN was found in the connective tissue surrounding the tumour cell nests and in narrow stromal strands inside the tumour. Regions infiltrated with lymphocytes were devoid of TN. The presence of TN around capillaries in melanocytomas and melanomas was investigated by double-immunolabelling (for TN and vWF). The intensity of vWF and TN immunolabelling was higher in melanomas than in melanocytomas, and higher in toe melanomas than in oral melanomas; however, no clear relation between TN expression and immunolabelling for vWF was found.

Avian hepatic granuloma. A review.

Hepatic granuloma is a chronic inflammatory disease characterized by a granulomatous reaction with accumulation of macrophages and/or epithelioid cells, which may fuse to form multinucleated giant cells. The hepatic granulomas typically have a surrounding rim of lymphocytes and fibrous tissues. The etiology of some hepatic granulomas in birds is well known. It could be due to viral, bacterial, fungal, protozoal, or helminthic infection. The presence of these pathogens in the liver is usually through systemic infections that might preferentially colonize the liver or be opportunistic invaders. Persistence of these pathogens infecting the liver can lead to granulomatous inflammation with different gross lesions and histopathologic patterns depending on the causative agent. This review describes the etiology, clinical signs, pathological changes, and diagnosis in a wide variety of diseases associated with hepatic granulomas in birds in which the detection of granulomatous inflammation is an aid in the differential diagnosis.

Relationship of plasma nonesterified fatty acids and walking activity in postpartum dairy cows.

To survive and produce milk, postpartum dairy cows use their reserves through lipolysis. If the negative energy balance is severe, nonesterified fatty acids (NEFA) are formed that can impair several physiological processes. A pilot study suggested that increased walking activity after calving may be related to a reduced serum concentration of NEFA. The objective of this study was to determine the relationship between plasma concentrations of NEFA and walking activity in dairy cattle during the postpartum period. Data were collected from 33 multiparous Holstein-Friesian dairy cows. Walking activities were quantified using pedometry, and blood samples were collected for determination of NEFA. Results of this study indicated that a negative relationship existed between walking activity and plasma NEFA concentrations in postpartum dairy cows.

An overview of swine influenza.

Swine influenza is a highly infectious viral disease of pigs, causing considerable economic impact. The causative agent is known as a type A orthomyxovirus with a segmented RNA genome. Influenza type A virus is a highly contagious pathogen among a limited number of birds and mammals. The objective of this review is to summarize the current knowledge in swine influenza infection in pigs with emphasizing on epidemiology, pathogenesis, diagnostic techniques and control measures.

Glycosaminoglycans are part of amyloid fibrils: ultrastructural evidence in avian AA amyloid stained with cuprolinic blue and labeled with immunogold.

In domestic brown layer fowl, reactive amyloidosis of internal organs, such as liver and spleen, and of the joints is a common disorder. In a variety of amyloid types including the AA-amyloid of the chicken, in addition to amyloid fibrils, proteoglycans and glycosaminoglycans (GAGs) are found on immunohistochemistry or after extraction. The aim of the present report is to study amyloid fibrils for the ultrastructural location of GAGs by cuprolinic blue staining and immunogold labeling. Rabbit antichicken AA antiserum was used for the immunogold labeling on conventionally embedded and cryoembedded liver tissue and revealed similar results. Therefore conventional blocks could be used for further analysis. Cuprolinic blue staining was performed on blocks of joint tissue in which clearly discernable rod-shaped glycoproteins were encountered in between collagen fibrils. Moreover, it appeared to stain larger deposits which might represent amyloid. Postlabeling with the immunogold method of the cuprolinic blue-stained tissue proved that cuprolinic blue positive fibrils represented AA-amyloid fibrils. Therefore, it was concluded that the GAGs which appeared to colocalize with the fibrillar microanatomy of amyloid, represent a structural part of the amyloid fibrils and that the avian amyloid fibrils may be considered as a pathological proteoglycan.

Cognitive disturbances in old dogs suffering from the canine counterpart of Alzheimer's disease.

In geriatric dogs, Alzheimer-like behavior is frequently observed. This behavior has been classified by several authors using questionnaires and a correlation has been described between cognitive dysfunctions and Alzheimer-like pathology. In the present study, cognitive performance was correlated with brain pathology for 30 dogs of varying ages. Within these animals, two age-matched groups of old dogs with and without behavioral changes were compared. The behavioral changes were analyzed and scored with questionnaires and necropsy was performed to rule out any other cause for changed behavior. Measurements, (immuno)-histochemical staining and fluorescence microscopy were used to detect cortex atrophy, amyloid, rest-products of oxidative damage, demyelination and accumulations of macrophages in the brains of these dogs. Spearman rank correlation coefficients (r) were calculated and adjusted according to Bonferonni. In the whole group (young to very old dogs), the age of the animal showed a significant correlation with various behavioral changes (r = 0.7 to 0.9, P < 0.01). The dementia score correlated significantly (r = 0.6 to 0.8, P < 0.01) with all the brain lesions studied, except one, i.e. demyelination (r = -0.4, P > 0.05). These results suggest that a questionnaire can be used to diagnose Alzheimer-like changes in canine practice. Oxidative damage on a cellular and a nuclear level plays an important role in behavior changes.

Acute phase reaction and acute phase proteins.

A review of the systemic acute phase reaction with major cytokines involved, and the hepatic metabolic changes, negative and positive acute phase proteins (APPs) with function and associated pathology is given. It appears that APPs represent appropriate analytes for assessment of animal health. Whereas they represent non-specific markers as biological effect reactants, they can be used for assessing nutritional deficits and reactive processes, especially when positive and negative acute phase variables are combined in an index. When such acute phase index is applied to separate healthy animals from animals with some disease, much better results are obtained than with single analytes and statistically acceptable results for culling individual animals may be reached. Unfortunately at present no cheap, comprehensive and easy to use system is available for assessing various acute phase proteins in serum or blood samples at the same time. Protein microarray or fluid phase microchip technology may satisfy this need; and permit simultaneous analysis of numerous analytes in the same small volume sample and enable integration of information derived from systemic reactivity and nutrition with disease specific variables. Applying such technology may help to solve health problems in various countries not only in animal husbandry but also in human populations.

Constitutive expression of functional CD40 on mouse renal cancer cells: induction of Fas and Fas-mediated killing by CD40L.

CD40, a member of the TNF receptor superfamily, is expressed on B cells, dendritic cells, and some tumor cells, including melanoma and bladder carcinoma. In this study, we report that both mouse and human renal carcinoma cells (RCC) also constitutively express functional CD40. Treatment of mouse RCC with CD40L induced strong expression of genes and proteins for ICAM-1 and Fas, and this expression was further enhanced by combining CD40L with IFN-gamma. Similar effects were demonstrated using an agonist anti-CD40 antibody. The increased levels of Fas expression on RCC after treatment with CD40L plus IFN-gamma resulted in potent killing by either FasL-positive effector cells or agonistic anti-Fas antibody. The combination of CD40L plus IFN-gamma also significantly enhanced killing of RCC by tumor-specific CTL lines. Our results demonstrate that constitutively expressed CD40 is functionally active and may provide a molecular target for the development of new approaches to the treatment of RCC.

Postweaning multisystemic wasting syndrome (PMWS) in pigs with particular emphasis on the causative agent, the mode of transmission, the diagnostic tools and the control measures. A review.

Postweaning multisystemic wasting syndrome (PMWS) is a worldwide emerging disease of weaned piglets. The objective of this review is to summarize the current knowledge regarding PMWS, its causative agent, mode of transmission, diagnostic techniques to detect PCV-2, the possible control measures, and the association of PMWS and PCV-2 with porcine dermatitis and nephropathy syndrome (PDNS). The causative agent of PMWS is porcine circovirus type 2 (PCV-2), however, not all pigs infected with PCV-2 develop the syndrome. PCV-2 is consistently associated with PMWS and PMWS is considered not to occur without it. Both the syndrome and the virus are not regarded as new. Co-factors that could activate PCV-2 to cause PMWS are considered. This enigmatic nature of both the syndrome and the virus is triggering a concern towards uncertainties of the viral transmission, its introduction in to the herd, effective tools of diagnosis, and control strategies.

Non esterified fatty acids (NEFA) in dairy cattle. A review.

The objective of this report is to review the literature on elevated blood concentrations of nonesterified fatty acids (NEFA) before and after parturition in high-yielding dairy cows. It highlights the factors that influence serum NEFA production and their circulation before and after parturition, such as adaptation for nutrient partitioning for fetal needs, onset of lactogenesis, stress of calving and numerous changes in physiological, metabolic, and endocrine status to accommodate parturition and lactogenesis. The role of NEFA in the liver and peripheral tissues and its toxic effects when in excess are discussed. The cow's adaptive physiologic mechanisms to prevent or decrease excessive values of serum NEFA and preventive and therapeutic interventions to enhance these mechanisms are categorized as natural and artificial antidotes respectively. Feeding systems during the dry period and daily exercise or walking activity which may burn excessive NEFA through beta-oxidation in the muscles are considered as more useful antidotes to managing the NEFA metabolism. This will minimize accumulation of lipids in the liver during early lactation and alleviate the negative effects of plasma NEFA leading to more optimal metabolic health and productivity of dairy cows.

Microcomputed tomography and histology of a fragmented medial coronoid process in a 20-week-old golden retriever.

A 20-week-old male golden retriever, which was not lame and showed no clinical signs of a fragmented medial coronoid process (FCP), was euthanased for another study and perfused intravenously with formaldehyde. Gross dissection revealed no abnormalities within the right elbow joint. The medial coronoid process was excised, embedded in methylmethacrylate, scanned in a microcomputed tomography (microCT) scanner and sectioned for histology. The microCT scans revealed a dense trabecular bone structure, much denser than in other dogs of similar age, which was considered to be responsible for the sclerosis visible at the base of the coronoid process in radiographs. Three-dimensional reconstructions indicated that there was a small step within the subchondral bone, extending from the apex towards the radial notch. Histology revealed a necrotic lesion between locally thickened articular cartilage and the subchondral bone, characteristic of osteochondrosis.

Extrahepatic production of acute phase serum amyloid A.

Amyloidosis is a group of diseases characterized by the extracellular deposition of protein that contains non-branching, straight fibrils on electron microscopy (amyloid fibrils) that have a high content of beta-pleated sheet conformation. Various biochemically distinct proteins can undergo transformation into amyloid fibrils. The precursor protein of amyloid protein A (AA) is the acute phase protein serum amyloid A (SAA). The concentration of SAA in plasma increases up to 1000-fold within 24 to 48 h after trauma, inflammation or infection. Individuals with chronically increased SAA levels may develop AA amyloidosis. SAA has been divided into two groups according to the encoding genes and the source of protein production. These two groups are acute phase SAA (A-SAA) and constitutive SAA (C-SAA). Although the liver is the primary site of the synthesis of A-SAA and C-SAA, extrahepatic production of both SAAs has been observed in animal models and cell culture experiments of several mammalian species and chicken. The functions of A-SAA are thought to involve lipid metabolism, lipid transport, chemotaxis and regulation of the inflammatory process. There is growing evidence that extrahepatic A-SAA formation may play a crucial role in amyloidogenesis and enhances amyloid formation at the site of SAA production.

Acute phase reactants, challenge in the near future of animal production and veterinary medicine.

The future of acute phase proteins (APPs) in science is discussed in this paper. Many functions and associated pathological processes of APPs are unknown. Extrahepatic formation in local tissues needs attention. Local serum amyloid A (SAA) formation may be involved in deposition of AA-amyloid induced by conformational change of SAA resulting in amyloid formation, having tremendous food safety implications. Amyloidogenesis is enhanced in mouse fed beta pleated sheet-rich proteins. The local amyloid in joints of chicken and mammary corpora amylacea is discussed. Differences in glycosylation of glycoproteins among the APPs, as has been shown for alpha1-acid glycoprotein, have to be considered. More knowledge on the reactivity patterns may lead to implication of APPs in the diagnostics and staging of a disease. Calculation of an index from values of several acute phase variables increases the power of APPs in monitoring unhealthy individuals in animal populations. Vaccinations, just as infections in eliciting acute phase response seem to limit the profitability of vaccines because acute phase reactions are contra-productive in view of muscle anabolism. Interest is focused on amino acid patterns and vitamins in view of dietary nutrition effect on sick and convalescing animals. When inexpensive methodology such as liquid phase methods (nephelometry, turbidimetry) or protein array technology for rapid APP measurement is available, APPs have a future in routine diagnostics. Specific groups of patients may be screened or populations monitored by using APP.

A study of seven different types of grafts for jugular vein transplantation in the horse.

The aim of this study was to investigate the biological behaviour of vascular grafts replacing a section of the jugular vein in order to improve the results of the surgical treatment of complete thrombosis of the jugular vein in the horse. Seven graft types: fresh allograft, home frozen allograft, glutaraldehyde-fixed allograft, cryo-preserved allograft, PTFE-graft (Gore), small intestinal submucosa preparation (Cook) and fresh autograft, were randomly implanted in ponies. The grafts were removed after one month and examined histologically for: preservation of the graft structures, acceptance by the host, intima proliferation, presence of endothelium and patency. The glutaraldehyde- and cryopreserved grafts show reasonable results and the PTFE and autograft had the best results especially with respect to host acceptance, endothelium presence and patency. Further research is necessary to improve graft behaviour, especially to the aspect of endothelisation. Obstruction of the jugular vein in horses can be treated surgically.