Ovine and Bovine Congenital Abnormalities Associated With Intrauterine Infection With Schmallenberg Virus

In December 2011, a previously unknown congenital syndrome of arthrogryposis and hydranencephaly in sheep and cattle appeared in the Netherlands as an emerging epizootic due to Schmallenberg virus (SBV). Gross lesions in 102 lambs and 204 calves included porencephaly, hydranencephaly, cerebellar dysplasia and dysplasia of the brainstem and spinal cord, a flattened skull with brachygnathia inferior, arthrogryposis, and vertebral column malformations. Microscopic lesions in the central nervous system showed rarefaction and cavitation in the white matter, as well as degeneration, necrosis, and loss of neurons in the gray matter. Brain and spinal cord lesions were more severe in lambs than in calves. Ovine and bovine cases examined early in the outbreak showed encephalomyelitis. SBV infection was confirmed by real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) in brain samples in 46 of 102 lambs (45%) and in 32 of 204 calves (16%). Immunohistochemistry, performed on tissue samples from 18 RT-qPCR-positive lambs, confirmed the presence of bunyaviral antigen in neurons of the brain in 16 cases. SBV antibodies were detected by enzyme-linked immunosorbent assay in fetal blood in 56 of 61 sampled ovine cases (92%). In a virus neutralization test, all tested dams of affected newborns, 46 ewes and 190 cows, were seropositive. Compared with other teratogenic viral infections, the pathogenesis and lesions of SBV in sheep and cattle fetuses are similar to those of other ruminant orthobunyaviruses. However, the loss of spinal ventral motor neurons and their tracts, resulting in micromyelia, distinguishes SBV infection from other viral central nervous system lesions in newborn ruminants.

[Postvaccinal fatal Streptococcus zooepidemicus necrotizing fasciitis in a young dog: a case report]

A 2.5-years-old female mongrel dog was routinely subcutaneously vaccinated. A few hours later mental dullness was noticed by the owner progressing into stupor the next day and resulting in a comatose state and death within 48 hours after vaccination. At post mortem examination, which was extended with histology and bacteriology, a necrotizing fasciitis and bacteremia caused by Streptococcus equi subsp. zooepidemicus were established. In the isolated Streptococcus strain four different superantigens were demonstrated that appeared to be able to produce exotoxins in vitro. Therefore, it is concluded that the minor skin trauma caused by vaccination enabled this strain to gain access to the subcutaneous tissue and to induce a necrotizing fasciitis. This process was complicated with a bacterial septicemia leading to death of the dog within 48 hours.

Severe combined immunodeficiency in Frisian Water Dogs caused by a RAG1 mutation

Mortality of pups at 8-12 weeks of age was frequently observed in Frisian Water Dogs. Blood parameters and clinical signs of newborns from three litters were monitored. Three pups from two litters showed strongly reduced levels of immunoglobulins and lymphocytes. These dogs were euthanized after first display of disease. Concurrent clinical and pathological features were consistent with a diagnosis of severe combined immunodeficiency (SCID). Defective V(D)J recombination is one of the causes of SCID in humans and animals. Eight genes involved in V(D)J recombination were investigated by segregation analysis of closely located microsatellite markers and by DNA sequence analysis. A nonsense mutation in the gene coding for V(D)J recombination factor RAG1 was identified in DNA from the cases at a position similar to that of nonsense mutations found in human SCID. It was concluded that SCID due to a mutation of RAG1 led to the high mortality.

[Botulism in dairy cattle in 2008: symptoms, diagnosis, pathogenesis, therapy, and prevention]

Botulism affects about 20 dairy herds a year in the Netherlands. This article describes the dramatic outcome of botulism in a dairy herd. The main clinical symptoms in this herd were increased lying down, slight ataxia of the hind legs, and a high mortality (98%). The diagnosis is difficult to establish in adult cattle, and for this reason the clinical and laboratory findings, differential diagnosis, therapy, and preventive measures are discussed. On the basis of this outbreak, previous experience with botulism, and cases described in literature, it is suggested that presence of 'free-range" poultry could contaminate grazing pastures with botulism neurotoxins, causing clinical problems in cattle. If there is an increased risk of contamination of the pasture and/or silage with botulinum neurotoxins, vaccination should be considered to prevent substantial economic and emotional damage.

[Claw health in Dutch dairy herds, an update of some recent disorders]

The dairy practitioner can make an important contribution to animal welfare by preventing and treating painful claw disorders. Two relatively new claw disorders have been observed in Dutch dairy herds, namely, toe ulceration and non-healing white line disorder. This article provides an update of knowledge on these two disorders, the aetiology of which is not known yet.

Comparison of clinical and pathological diagnoses in dogs

Clinical and pathological diagnoses were compared in a prospective study of 145 dogs. A diagnostic work up had been performed on all dogs of which 36 (24.8%) died and 109 (75.2%) were euthanatized. In 119 dogs (82.1%) both a clinical and patholical diagnosis was made, in 20 dogs (13.8%) no pathological diagnosis could be made and in 6 dogs (4.1%) no clinical diagnosis was established. In the 119 dogs the agreement level between clinical and pathological diagnosis was scored by the referring veterinarian together with a pathologist. Total agreement was found in 61 cases (51.3%) and disagreement in 31 cases (26.0%). In the remaining cases (27=22.7%) the pathological diagnosis further specified the clinical diagnosis. Consecutive submission appeared difficult to achieve by the participating veterinarians. However, no major differences in agreement level was present between the veterinarian which succeeded in almost consecutive submissions and the other veterinarians. At necropsy 42 cases were diagnosed as neoplasia, of which 52.4% had been diagnosed clinically. As to infectious diseases 55.0% of these diseases diagnosed at necropsy had been diagnosed clinically. In about 20% of the cases the differences were of clinical significance according to the referring veterinarians. In addition, it was indicated by the clinicians that about 50% of the necropsies revealed findings which could amend future patient care. The results of the study stress the relevance of postmortem examination as crucial part of continuing education and of quality monitoring and assurance in veterinary medicine.

Ability of veterinary pathologists to diagnose classical swine fever from clinical signs and gross pathological findings

Clinical signs recorded in a classical swine fever (CSF)-suspect situation and the results of the subsequent post-mortem examination (PME) from swine submitted to post-mortem during the 1997-1998 CSF epidemic in the Netherlands, were presented in an experiment as anonymous cases (without knowledge of the actual infection status of the submission) to five veterinary pathologists for their judgment: CSF-suspect or non-suspect. It was presented to them in two hypothetical situations: country was free of CSF for 5 years and CSF was detected in the country 2 weeks ago. Subsequently, their judgment was compared to the gold standard (infection status of the submission on the basis of an immunofluoresence assay on tissue samples) and the sensitivity (Se) and specificity (Sp) of clinical diagnosis was estimated. Furthermore, intra- and inter-pathologist agreement on pathological diagnosis was measured. Adding information on clinical signs to information on PME resulted in a significant increase in median Se and a significant decrease in median Sp for a clinical judgment by pathologists. Also, median Se was significantly higher-and Sp significantly lower-for a clinical judgment by pathologists in a situation in which CSF was detected 2 weeks ago in the country compared to the situation in which the country had been free of CSF for 5 years. Apparently, the internal threshold of pathologists is severely adjusted depending on the actual disease situation in a country. Intra-rater agreement ranged from fair to almost perfect for a clinical diagnosis on the basis of PME. There was considerable variation between pathologists, especially if clinical diagnosis was based on the combined information on PME and clinical signs observed in the herd. Inter-rater agreement was substantial for the diagnosis based on information on PME. Inter-rater agreement was considerably lower for the diagnosis based on the combined information on PME and clinical signs observed in the herd.

Prevalence of exposure and infection of Lawsonia intracellularis among slaughter-age pigs

The extent of clinical or subclinical infection associated with Lawsonia intracellularis within Dutch pig herds was uncertain. A case-control study of slaughter age pigs was used to study natural infection within Dutch herds and to compare diagnostic methods. From six case herds where clinical disease had been identified recently, and six disease-free herds, 40 pigs of slaughter-age were examined postmortem. The diagnostic methods used were: serology, gross examination, Haematoxylin and Eosin stain (HE), Warthin-Starry silver stain, Lawsonia-specific indirect immunoperoxidase of the ileum, and PCR of ileum mucosa and colon contents. There were 59% seropositive pigs in case herds and 26% seropositive pigs in control herds. Using immunohistochemistry, 57% of case herds and 46% of control herds were bacteria positive in the ileum mucosa. It was concluded that a majority of Dutch herds contain L. intracellularis infected finisher pigs. In some herds this is associated with clinical outbreaks of acute haemorrhagic enteropathy but in other herds no clinical disease is apparent. Many seropositive pigs in herds without clinical disease had evidence of Lawsonia antigen in sites other than the apical cytoplasm of proliferating epithelial cells, particularly the supranuclear region. It was uncertain whether to classify these pigs as having "recovered" from an infection or whether they have a sub-clinical or chronic form of the disease. We concluded that PCR examination of faeces and serology probably provide more specific results than gross examinations at slaughter, and that a monoclonal antibody-based examination of ileum mucosa should be the accepted screening method for this infection.

[Death by cyathostominosis]

In autumn 2002 and 2003, the Animal Health Service received several young horses for post mortem investigation that had died or had been euthanised. It was found that severe cyathostominosis was the cause of death. The aetiology, pathology and diagnosis of this infection is discussed. Advice is given for preventative measures and usage of anthelmintics.

[Idiopathic gastric rupture in a Friesian foal]

Acute idiopathic gastric rupture resulted in sudden death of a 4.5-months-old healthy Friesian foal. No morphological lesions were present which could explain the preceding gastric impaction. In this case hypodypsia may have been (partially) responsible for the impaction as only a mechanical drinking apparatus, unsuitably for horses, was available.

[Senecio jacobaea: deceiving beauty. Senecio jacobaea poisoning]

In a cattle herd problems were noticed during 1.5 years, characterised by emaciation and loss of milk production with lower fat- and protein%, tenesmus, central nervous symptoms (aggression, circling and blindness), diarrhoea, eczema solare and death. Clinical, laboratory and post mortem examinations did not reveal a specific cause at first. An intoxication was suspected based on the clinical symptoms, the course of the disease in sick animals and severe liver cirrhosis found in a sudden death cow: The animals were fed grassilage derived from an air force base on which an overwhelming amount of tansy ragwort (Senecio jacobaea) was present. On subsequent microscopic examination of the livers of 11 slaughtered clinically healthy animals all of these showed fibrosis in varying extension. Cirrhosis and fibrosis of the liver and the clinical symptoms are all features of chronic pyrrolyzidine alkaloidosis. Tansy ragwort poisoning has not been diagnosed in the Netherlands for years. The rise in cases is due to more extensive use of land.

[Veterinarians:'Watch your affairs!']

The most relevant results of a written questionnaire among veterinarians in the Netherlands are presented and discussed. The inquiry was performed by MarketResponse Nederland BV. The objective was to get an overview of the current perception and the future view of the profession. The response was 37%. Most respondents (66%) were practitioners, 7% were active in research or teaching institutions, 5% were governmental employees, 5% were employed in industry, and 17% did not belong to any of these categories (retired, unemployed etc.). Forty-seven per cent of the veterinarians practised mainly small animal medicine, 24% large animal medicine (cattle 15%, swine 8%, and poultry 1%), and 4% equine medicine; 24% worked in mixed practices. This division reflects the real-life situation. The percentage of female respondents was considerably higher in the group of recent graduates than in the other groups of graduates (increasing from 27% in the graduation period 1980-1989 to 56% in the period 1990-1999). Sixty per cent of the veterinarians worked more than 40 hours a week. Veterinarians considered themselves reliable, honest, professional, client-minded, and animal-friendly. According to them, the public perceived veterinarians as being animal-friendly, professional, and reliable. Veterinarians were less satisfied in their current position than other professional groups, particularly with regard to their income. Their current market position was considered indifferent or good. This position was influenced negatively by the decrease in the number of animals and competition from non-veterinarians and others. The situation could be improved by collaboration and practice fusions, specialization, and differentiation. More demanding and price-conscious clients and governmental regulations were considered important trends. Social, management, and marketing skills, increased knowledge and cooperation, and a vision of future developments were considered essential in order to be able react to developments on the market. About 60% of the practitioners and 50% of the other veterinarians felt that they lacked the right skills, and especially management and marketing skills, to react to these developments adequately. Most veterinarians (77%) considered that their training did not provide them with the skills needed for their current position. During training, more time should be spent on management, communication, marketing, and social skills. Based on the results, veterinary medicine in the Netherlands seems to be an introspective but good profession; however, the interesting aspects of the profession appear to be over-shadowed by less appreciated aspects and the income is moderate. Entrepreneuship is poorly developed, in part because this is considered taboo. The importance of skills that are not an integral part of veterinary medicine, such as management, marketing, and communication, is recognized, as is the lack of these skills. Despite this, emphasis is put on continuing professional education, species specialization, modernization, accreditation, and expansion of facilities and treatment possibilities as ways to respond to the market situation.

Slaughter pigs are commonly infected by closely related but distinct gastric ulcerative lesion-inducing gastrospirilla

An association between (unculturable) gastrospirillum-like organisms (GLO) and ulcerative lesions in the pars oesophagea in stomachs of swine has been claimed. In dogs GLO detected by microscopy may represent several Helicobacter species or subspecies. Therefore we investigated which Helicobacter spp. are present in stomachs of swine and their possible association with ulcerative lesions of the pars oesophagea. The presence of Helicobacter spp. in the antrum and pars oesophagea in 122 stomachs of slaughter swine was determined by microscopy (n = 122), by culture on selective and nonselective media (n = 112), and by a genus-specific 16S ribosomal DNA (rDNA) PCR (n = 80). GLO could not be cultured. Phylogenetic analysis of 43 16S rDNA fragments (out of 54 PCR-positive biopsy specimens) revealed the presence of Helicobacter heilmannii type 1 in 42 of them. This correlated with the presence of bacteria with GLO morphology. Helicobacter bilis 16S rDNA was amplified directly from one sample harboring bacteria with H. bilis morphology. The association between Helicobacter spp. and gastric lesions was investigated with a second group of 41 pigs with (n = 21 cases) or without (n = 20 controls) gastric lesions. Fifteen of the 21 cases were positive by PCR or microscopy, compared to 7 of 20 of the controls (P = 0.03). 16S rDNA sequence analysis of 7 of 14 PCR-positive cases revealed the presence of H. heilmannii type 1. Microscopy showed bacteria with GLO morphology. One sample (cases) was culture negative but PCR positive for Helicobacter pullorum-related 16S rDNA. In conclusion, our findings indicate that H. heilmannii type 1 is the predominant Helicobacter spp. in the stomachs of pigs and that its presence is associated with ulcerative lesions in the pars oesophagea.

Effect of hammer mill screen size and addition of fibre or S-methylmethionine-sulphonium chloride to the diet on the occurrence of oesophagogastric lesions in fattening pigs

Four groups of about 86 pigs from a common source were fed a grower diet from 25 kg to 45 kg liveweight, and then from 45 to 107 kg liveweight they were offered one of four diets ad libitum: A) normal commercial feed, ground through a 3 mm screen (the control diet), B) the same diet ground through a 6 mm screen, C) the control diet to which lucerne meal was added before the diet was ground to increase its crude fibre content, and D) the control diet to which was added 400 ppm S-methylmethionine-sulphonium chloride (MMSC). All the diets were pelleted. Approximately 21 per cent of the animals fed the control diet had severe oesophagogastric erosions and/or ulcers after slaughter. The addition of 400 ppm MMSC decreased (P = 0.066) the proportion of severe oesophagogastric erosions and/or ulcers by about 50 per cent compared with the control diet. The diet with the higher crude fibre content (but finely ground) did not have a significant effect on the proportion of severe oesophagogastric erosions and/or ulcers. There was a tendency for the pigs fed the diet ground through a 6 mm screen instead of a 3 mm screen, to have fewer severe oesophagogastric erosions and/or ulcers. However, there were only small differences between the particle size distribution obtained from the wet sieve analysis of the two diets. As a result, the observed tendency for a decrease in the proportion of severe oesophagogastric erosions and/or ulcers in pigs fed the diet milled through the larger screen size was of questionable significance.(ABSTRACT TRUNCATED AT 250 WORDS)

A survey of the relationship between bile staining and oesophagogastric lesions in slaughter pigs

In 280 slaughter pigs, the oesophageal region of the stomach was examined to test the hypothesis that there is a (causal) relationship between the intensity of bile staining of oesophagogastric tissue due to bile regurgitation and the severity of oesophagogastric lesions. When the stomachs were opened, almost all stomachs contained bile and 99.6% of stomachs showed bile staining of the pars oesophagea. A total of 14.3% of the stomachs showed distinct erosions and/or ulceration. A considerable proportion of the stomachs (58.5%) had hyperkeratosis as the only lesion. Only two animals showed a completely intact epithelium. There was no evidence for an increased proportion of oesophagogastric lesions with an increased intensity of bile staining. No dark yellow to green staining was observed; a just detectable to an obvious yellow was seen. This is an indication for bile regurgitation of recent origin. Therefore, there is no evidence for the hypothesis that the regurgitation of bile into the stomach is positively linked to the occurrence of oesophagogastric lesions in fattening pigs. It is suggested that various factors associated with slaughter, such as fasting and slaughter procedure, are primarily responsible for the presence of bile and the staining of the pars oesophagea in the stomachs.

Cultured pig rhabdomyosarcoma cells with a deletion of the Xq24-qter chromosome region: an immunochemical and cytogenetic characterization

A pig rhabdomyosarcoma cell line (PRUM59) was established, and the immuno(histo)chemical and cytogenetic characterization of these cells was determined. At various swine farms in the Netherlands, pigs were observed that had solitary or multiple skin nodules, which were diagnosed as rhabdomyosarcomas. Cells of a tumor derived from a 3.5-week-old female pig were cultured for immunochemical and cytogenetic analyses. The cell line had characteristic features of undifferentiated muscle cells, similar to those observed in tumor tissue sections; they contained titin, a high-molecular weight protein specific for striated muscle, as dot-like aggregates and as filaments, desmin filaments and cross-striations, smooth muscle actin stress fibers, and vimentin filaments. The cells stained positively for striated muscle actin and tropomyosin as well. The immunohistochemical staining results were supported by results of immunoblotting experiments. Karyotyping of the cells revealed a deletion of a major part of Xq24-qter, a part of the long arm of 1 of the 2 X chromosomes. The other X chromosome and all autosomes appeared to be normal.

Growth and oesophagogastric lesions in finishing pigs offered pelleted feed ad libitum

The growth rates of 458 finishing pigs between 25 kg and 107 kg liveweight, which were offered finely ground pelleted feed ad libitum, were determined and their stomachs were examined at slaughter. Two herds were involved and a macroscopical examination of the mucosal lesions in the pars oesophagea revealed a prevalence of 75 per cent of the 274 pigs in herd A and 89 per cent of the 184 pigs in herd B with hyperkeratosis of the pars oesophagea, and approximately 11 per cent of the pigs in both herds with extensive erosions and/or ulceration; on average the pigs with extensive lesions gained 50 to 75 g/day less weight than the pigs with no lesions in the pars oesophagea. There was no difference between the prevalence of the oesophagogastric lesions of different severity between barrows and gilts, but there was evidence for differences between litters.

[Tumor cells on the inside and tumor cells on the outside. A contribution to the diagnosis and elucidation of the pathogenesis of mammary tumors in dogs]

This review discusses some recent experience with intra- and extracellular components of tumours as markers for tumour diagnosis. Intermediate filaments are cytoskeletal proteins of either epithelial or mesenchymal cells. Antibodies raised against human intermediate filament proteins cross-react with their canine counterparts. A study of the presence and distribution of intermediate filaments in normal mamma and mammary tumours of dogs showed that they do not contribute to a more adequate classification of the tumours. However, the presence of vimentin in epithelial tumour cells may be a marker of malignancy. Proteoglycans are extracellular matrix proteins, containing long chains of glycosaminoglycans (GAGs). Analysis of the presence of GAGs in canine mammary tumours showed that accumulation of chondroitin sulfate, frequently of an abnormal type, was a predominant finding in all tumour types, but not in normal mamma, and was not related to biological behaviour. Although demonstration of the before-mentioned tumour components does not help tumour diagnosis, it may contribute to the elucidation of the development of such tumours as the complex and mixed adenomas of the mamma of which cartilage and bone are important constituents of unknown origin.

The canine p53 gene is subject to somatic mutations in thypoid carcinoma

In many different types of tumors in man and mouse, p53 is the tumor suppressor gene most frequently affected by a combination of somatic mutation and loss of the wildtype allele. In order to develop a molecular tool to study the genetic evolution of tumors in the dog, we have cloned an evolutionary conserved part of the canine homologue of p53. The isolated genomic segment, 534 bp in length, contains the 3' half of exon 5, the complete exon 6 and the 5' half of exon 7, as well as the intronic intervening sequences. The gene organization of this segment shows strong homology to that published earlier for a number of other species, including man, mouse, and Xenopus laevis. This conservation is apparent at the DNA sequence level, as well as at the deduced aminoacid sequence level. mRNA expression can be detected at low levels in normal tissues with increased mitotic activity, and in the Madin-Darby canine kidney cell line. A-->G T transversion was found in 1 out of 23 investigated primary thyroid carcinomas at a position corresponding to codon 174 in the human p53, and was predicted to give rise to an aminoacid substitution in the protein. These results suggest that p53 plays a role in the development of malignancy in the dog, in a way comparable to that in man.

Clustering in canine malignant lymphoma

A clustering of generalized malignant lymphoma is reported in a single household of Rottweiler dogs (both parents and three of the four sibling in one litter) and in a breeding pair of unrelated Scottish terriers. In addition, malignant lymphoma of the myocardium was found in three directly related otterhounds (the sire and two sibling offspring). Possible genetic and viral factors in the aetiology of canine malignant lymphoma are discussed.

Immunohistochemical distribution of keratin proteins in feline tissues

The immunohistochemical distribution pattern of some keratin intermediate filament proteins has been analysed in a wide range of formalin fixed, paraffin embedded feline tissues using one polyclonal and two monoclonal antibodies raised against human keratins by means of the avidin-biotin-peroxidase complex technique. Only the epithelial and mesothelial cells were stained by the three antibodies, but differences in their corresponding staining pattern were noticed. The staining reaction of the polyclonal antibody raised against human skin keratin was found in both stratified and complex epithelia, while that of the monoclonal antibody which recognizes human keratins 8 + 18 + 19 of the Moll catalogue (NCL-5D3) was restricted to some simple epithelia. The staining reaction of the monoclonal antibody which reacts with human keratins 5 + 8 of the Moll catalogue (RCK-102) covered the widest spectrum of feline epithelial tissues analysed, including stratified, complex and simple epithelia. These staining patterns of feline tissues are basically similar with respect to those of corresponding tissues in other mammalian species, although some differences were also noticed and some obvious epithelial tissues were not stained. This study confirms the broad interspecies cross-reactivity of keratin proteins antibodies and demonstrates their capability to differentiate between various types of feline epithelia and some epithelial compartments.

Immunohistochemical distribution of vimentin, desmin, glial fibrillary acidic protein and neurofilament proteins in feline tissues

The immunohistochemical distribution pattern of vimentin, desmin, glial fibrillary acidic protein and neurofilaments intermediate filament proteins has been analyzed in a wide range of formalin fixed, paraffin embedded tissues using polyclonal and monoclonal antibodies raised against non-feline antigens. The vimentin antibody reacted with mesenchymal cells, the desmin antibody with striated and smooth muscle fibres, the glial fibrillary acidic protein antibody with glial cells in the central and peripheral nervous system, and the neurofilament proteins antibody with neuronal cell bodies and processes. In addition, some epithelial cells were vimentin positive, perisinusoidal liver cells were desmin positive, and basal/myoepithelial cells of the mammary gland, and luteinic cells were glial fibrillary acidic protein positive. These staining patterns of feline tissues are basically similar with respect to that of corresponding tissues in other mammalian species for each of the four intermediate filament proteins studied, but some differences have been also noticed. This study confirms the broad interspecies cross-reactivity of intermediate filament proteins antisera and demonstrates their capability to differentiate particular types of feline cells and tissues.

Expression of epidermal growth factor receptor (EGFR) in non-affected and tumorous mammary tissue of female dogs

Epidermal growth factor (EGFR), oestrogen (ER), and progestin (PR) receptor concentrations were determined by radioligand binding assay in non-affected mammary tissues (n = 13) and benign (n = 11) and primary/locally recurrent malignant proliferative mammary lesions (n = 45) and metastases (n = 19) in 65 female dogs. The number of specimens expressing EGFR was not significantly different among these tissues, but EGFR concentration was lower in metastases (P = 0.02) than in benign or primary/locally recurrent malignant lesions not mixed with non-affected mammary tissue. The presence of non-affected mammary tissue in primary cancer specimens was noticed as a factor that may influence results of receptor measurements. No relation was found between the expression of EGFR and that of ER or PR in non-affected or in tumorous mammary tissues. It was concluded that in the dog mammary gland EGFR expression is not associated with conditions of steroid receptor absence of biological agressiveness of neoplastic growth.

Immunohistochemistry with keratin, vimentin, desmin, and alpha-smooth muscle actin monoclonal antibodies in canine mammary gland: normal mammary tissue

Normal canine mammary gland tissue was studied immunohistochemically with monoclonal antibodies (MoAbs) directed against various human keratin types, vimentin, desmin, and alpha-smooth muscle actin. Both ductal and alveolar luminal cells were immunoreactive with MoAbs recognizing respectively human keratins no. 7, 8, 18 and 19. In addition, some ductal luminal cells were labelled with a keratin 4 and a keratin 10 MoAb. Basal/myoepithelial cells were immunoreactive only with MoAbs directed against keratin 14, keratins 14 and 17, and alpha-smooth muscle actin. The vimentin MoAb merely labelled solitary loose intraluminal cells representing macro-phages or sloughed epithelial cells. These findings correspond largely to observations made in human breast tissue.

Immunohistochemistry with keratin, vimentin, desmin, and alpha-smooth muscle actin monoclonal antibodies in canine mammary gland: benign mammary tumours and duct ectasias

Duct ectasias (n = 2) and different types of benign canine mammary tumours (n = 19) were studied immunohistochemically with monoclonal antibodies (MoAbs) directed against various human keratin types (K), alpha-smooth muscle actin, vimentin, and desmin. In the duct ectasias and in most tumours the epithelial structures revealed an inner and outer cell layer. The inner cell layer was characterized by labelling with K 7, 8, 18, 19 and mostly also with K 4 and/or K 10 MoAbs. The outer cell layer was almost invariably labelled by K 14, K 14 and 17, and a-smooth muscle actin MoAbs. The labelling patterns of both duct ectasias and tumours corresponded largely to the patterns observed in normal mammary gland tissue, although a more distinct heterogeneity was seen. Tumours histomorphologically assumed to be of a myoepithelial origin did not show immunohistochemical features of myoepithelial cells. The myoepithelial nature of the vast majority of spindle-shaped cells present in the adenomas of the complex type and in the fibroadenomas of the benign mixed type could not be confirmed immunohistochemically. These cells, however, unequivocally expressed vimentin, suggesting proliferation of stromal cells in these tumours, which in the fibroadenomas of the benign mixed type may show metaplasia to bone or cartilage. In the duct ectasias and in some tumours, a fraction of elongated stromal cells, probably representing myofibroblasts, was labelled with the alpha-smooth muscle actin MoAb.

Immunohistochemistry with keratin, vimentin, desmin, and alpha-smooth muscle actin monoclonal antibodies in canine mammary gland: malignant mammary tumours

Ten malignant canine mammary gland tumours and five metastases from three of these tumours were studied immunohistochemically with monoclonal antibodies (MoAbs) directed against different human keratin types (K), alpha-smooth muscle actin, vimentin, and desmin. In all tumours the neoplastic epithelium was rather homogeneously labelled with the keratin MoAbs RCK 102 (K 5 and 8) and CAM 5.2 (K 8). The adenocarcinomas (n = 5), the solid carcinomas (n = 2), and the carcinosarcoma (n = 1) showed heterogeneous labelling with the MoAbs specific for luminal cell antigens in the normal canine mammary gland, i.e., K 18, K 7 and K 19 MoAbs. These cells were also immunoreactive with K 4 and K 10 MoAbs. The spindle cell carcinomas (n = 2), however, did not react with these MoAbs. All tumours except one adenocarcinoma were characterized by the absence of immunoreactive labelling with the alpha-smooth muscle actin MoAb. In the solid carcinomas this was associated with the absence of labelling with one or both basal cell specific keratin MoAbs, i.e., 8.7 (K 14 and 17) and RCK 107 (K 14), respectively. In contrast, the other malignant tumours showed marked labelling of neoplastic epithelium with these MoAbs. Another remarkable finding was the labelling of a limited to moderate number of neoplastic epithelial cells with the vimentin MoAb. The presence of such labelling patterns in canine mammary gland tumours may be indicative of malignancy. Metastatic tumour tissues had a labelling pattern largely similar to that of the primary tumour, although also loss of reactivity for some keratin MoAbs was seen.

The expression of keratins, vimentin, neurofilament proteins, smooth muscle actin, neuron-specific enolase, and synaptophysin in tumors of the specific glands in the canine anal region

Eight canine tumors originating from specific glandular structures in the anal region, as well as metastatic tumor tissue of two of these cases (case Nos. 7, 8), were immunohistochemically analyzed using various monoclonal antibodies (MoAbs) directed against human keratin types, vimentin, neurofilament proteins, and alpha-smooth muscle actin. These tumors also were stained for the broad-spectrum neuroendocrine markers neuron-specific enolase (NSE) and synaptophysin. In histologically normal canine anal structures, alpha-smooth muscle actin and NSE antibodies stained basally localized (probably myoepithelial) cells in the anal glands and the anal sac glands. NSE staining also was present in a limited number of luminal cells in both anal glands and anal sac glands. Synaptophysin labeling was not observed in any of these glandular structures. Histologically, the tumors were differentiated into well- and moderately differentiated perianal gland tumors (n = 5) and carcinomas without perianal gland differentiation (n = 3), corresponding to the so-called apocrine carcinomas of the anal region. Immunohistochemically, the perianal gland tumors could be differentiated from the carcinomas by marked differences in staining pattern with the various keratin MoAbs, particularly MoAbs directed against human keratin types 7 and 18. The keratin-staining characteristics of the carcinomas suggest a glandular luminal cell origin. Metastases of the carcinomas showed loss of some keratin-staining characteristics as compared with the primary tumor. Staining for NSE was only observed in solitary cells and small cell clusters in the carcinomas and their metastases, whereas the alpha-smooth muscle actin antibody did not react with the carcinoma cells. None of the tumors stained for neurofilament proteins or synaptophysin. An unequivocal neuroendocrine nature of the carcinomas could not be substantiated by our immunohistochemical study, although the presence of a population of neuroendocrine cells within these neoplasms seems likely. Because the immunohistochemical features of the carcinomas with respect to various keratin MoAbs and NSE are similar to those of the anal glands and the anal sac glands, both these glands might be considered as site of origin of these carcinomas.

Rhabdomyosarcomas in young pigs in a swine breeding farm: a morphologic and immunohistochemical study

Within a 6-month-period, solitary or multiple tumors were observed in 25 young pigs in their first weeks of life in a swine breeding farm. The herd comprised approximately 100 animals, and affected pigs were observed in several litters. The number of affected littermates varied from one to three. Five animals, all from different litters and with a total of 11 tumors, were studied. Histologically the tumors were classified as undifferentiated sarcomas. Electron microscopic examination of the tumors (n = 3) revealed myogenic differentiation, characterized by the presence of numerous cytoplasmic filaments with longitudinal densities and cytoplasmic dense bodies. Immunohistochemically, all 11 tumors were labeled by vimentin and desmin antibodies. Two tumors from which frozen material was available were additionally labeled by a titin antibody but did not show immunoreactivity with antibodies directed against myosin and alpha-sarcomeric actin. The tumors were finally diagnosed as undifferentiated rhabdomyosarcomas. The high incidence of these tumors within a short period of time in multiple young animals in different litters indicates a common causative event. The clinical history suggests a genetic cause.

Relationship between negative skin test with Johnin after vaccination and post mortem findings

One hundred and seventy-six cattle, vaccinated against paratuberculosis in the first month of life with a whole-cell inactivated vaccine, containing Mycobacterium paratuberculosis suspended in a water/oil emulsion, were tested with intradermal Johnin between the ages of five and 14 months. Negative results in the skin test occurred more frequently in animals found positive in post mortem examinations (P = 0.008) using histological, microscopical and cultural techniques.

Immunohistochemistry with keratin monoclonal antibodies in canine tissues: urogenital tract, respiratory tract, (neuro-)endocrine tissues, choroid plexus and spinal cord

Twelve oligo- or monospecific monoclonal antibodies (MoAbs) directed against human keratin types were used in an immunohistochemical study of the canine male and female urogenital tract, the respiratory tract, the adrenal gland, the (para-)thyroid gland, the choroid plexus and the spinal cord. The keratin MoAbs showed differences in staining patterns in the various epithelial tissues and the diverse epithelial cells. The kidney was characterized by a complex keratin staining pattern and the canine urothelium showed regional differences in keratin staining. Also in the female genital tract different keratin staining patterns were observed. Testicular and adrenal gland cells did not react with any of the keratin MoAbs. The keratin staining patterns in the various canine tissues showed, in addition to similarities, also distinct differences when compared to the staining patterns in corresponding tissues of other species, e.g. of man. These staining dissimilarities indicate that the reactivity patterns of the keratin MoAbs with restricted keratin immunoreactivity can not be always extrapolated from one species to another. Nevertheless, MoAbs directed against human keratin proteins can apparently be used to differentiate between various types of canine epithelia or epithelial compartments.

Keratin and vimentin distribution patterns in the epithelial structures of the canine anal region

The intermediate filament labeling pattern of the epithelial structures of the canine anal region was studied with different polypeptide specific keratin monoclonal antibodies (MoAbs) and with a monoclonal and polyclonal vimentin antibody. The epithelial structures in this region could be discriminated and characterized by differences in their keratin staining pattern. The basal cells in the different epithelial structures showed a similar staining pattern characterized by reactivity with MoAbs staining keratins 5, 8, 14, and 17. Columnar epithelial cells showed a completely different phenotype mostly characterized by reactivity with MoAbs staining keratins 7, 5, 8, 18, and 19. A restricted number of differentiated perianal gland cells showed perinuclear vimentin staining. Myoepithelial cells did not stain for vimentin, but, as other basal cells, were positive for MoAbs staining keratins 5, 8, 14, and 17.

Malignant fibrous histiocytomas in dogs and cats: an immunohistochemical study

Immunohistochemical staining was performed on seven canine and 10 feline soft tissue tumours histologically diagnosed as malignant fibrous histiocytomas (MFHs) or MFH-like tumours, and eight other histologically specified tumours (non-MFH). This was done to determine if commercially available antibodies that are used routinely in human diagnostic pathology for MFHs would express the same immunohistochemical patterns in canine and feline MFHs and MFH-like tumours. The antibodies were directed against human alpha 1-anti-trypsin (AT), human alpha 1-anti-chymotrypsin (ACT), human lysozyme, bovine S-100 protein and human desmin. AT did not show any immunoreactivity in the tissues investigated. Except for one MFH, all canine MFHs and other soft tissue tumours with a 'histiocytic' character stained for lysozyme and not for S-100. Six out of seven canine MFHs and MFH-like tumours stained positive for desmin as did most non-MFH sarcomas. Most of the canine and feline MFHs and MFH-like tumours were positive for ACT. These findings for ACT staining in canine and feline MFHs and MFH-like tumours are in agreement with the findings in human MFHs. The immunohistochemical results of canine MFHs and MFH-like tumours were different from those in cats. Feline MFHs differed from canine MFHs for both lysozyme and desmin staining.

Hyperadrenocorticism in four cats

This paper describes four cats with hyperadrenocorticism. Cat 1 showed polydipsia and polyphagia. Diabetes mellitus was initially diagnosed. As the animal appeared to be insulin resistant, pituitary and adrenocortical function tests were performed and the diagnosis of hyperadrenocorticism was made. Resistance to the high-dose dexamethasone suppression test was noticed in this cat. Pathological examination revealed a pituitary chromophobe adenoma. Cat 2 presented with diabetes mellitus, which was treated with insulin. The animal had a pendulous abdomen and its coat was in a poor condition. The low-dose dexamethasone suppression test demonstrated hyperadrenocorticism. Necropsy findings of pituitary tumour and hyperplasia of the adrenal cortex confirmed the diagnosis. Cat 3 showed clinical abnormalities indicative of hyperadrenocorticism, for instance, muscle weakness, alopecia, multiple abscesses. The diagnosis of hyperadrenocorticism was confirmed by the results of the lowe-dose dexamethasone suppression test. Pathological examination revealed an adrenocortical carcinoma. Cat 4 presented with polydipsia. The cause of this symptom was not found initially. One and a half years later additional symptoms, such as nephritis and polyphagia developed. Hyperadrenocorticism was diagnosed because of a palpable mass cranial to the left kidney. The diagnosis was confirmed by the results of the lowe-dose dexamethasone suppression test and the necropsy findings.

Immunohistochemistry with keratin and smooth muscle actin monoclonal antibodies in canine digestive tract and extramural glands

The canine digestive system and its extramural glands (parotid gland, liver, pancreas) were immunohistochemically studied using a panel of twelve monoclonal antibodies (MoAbs) specific for human keratin proteins and for alpha-smooth muscle actin. Various epithelial tissues and cells were characterized by different keratin staining patterns. So, the epithelial lining of the upper alimentary tract was characterized by staining with the MoAb 6B10, specific for keratin-type (K) 4, and the absence of staining with the MoAbs directed against K 8 and 18 (CAM 5.2 and RGE 53, DE-K18 respectively), whereas the lower alimentary tract epithelium was not labeled by 6B10, but stained by the latter MoAbs. In the salivary glands the luminal and basal cells of the adenomeres as well as the different ductal structures could be immunohistochemically differentiated. The duct epithelium in liver and pancreas showed next to keratin staining characteristics in common with hepatocytes and exocrine pancreatic cells, additional staining by several keratin MoAbs. The keratin staining patterns in the canine tissues showed, in addition to similarities also distinct discrepancies when compared to the staining patterns in corresponding human tissues. Myoepithelial cells in salivary and oesophageal glands could be differentiated from other basally located epithelial cells by their exclusive immunoreactivity for alpha-smooth muscle actin. Canine pancreatic endocrine cells were not labeled by any of the keratin MoAbs. It is concluded that immunohistochemistry with polypeptide specific MoAbs specific for human keratin-types can be used to differentiate between different types of canine epithelial tissues and epithelial cells in the digestive tract. As a result such reagents may find their application in developmental biology and pathology of this species.

Thyrotrophin receptors in normal and neoplastic (primary and metastatic) canine thyroid tissue

Thyrotrophin (TSH) is the conditional growth factor of thyroid epithelial cells. Abnormalities in TSH-receptor binding such as a low receptor number or low binding affinity may be a marker of thyroid carcinoma or metastases, or may exhibit a relationship with the functional variability of such tissues. The dog was used as a model to characterize TSH-receptor binding in normal thyroid tissues, naturally occurring thyroid neoplasms and distant metastases. In normal dog thyroid tissues, specific 125I-labelled TSH binding ranged from 2.7 to 15.5%, and low cross-reactivity with bovine LH (0.023%) was observed. One class of TSH-binding sites was found in eight normal thyroid tissues and 22 thyroid carcinomas; two normal thyroid tissues and one tumour exhibited two classes of binding sites. The concentration of binding sites was lower in the five carcinomas with reduced pertechnetate uptake (0.09 pmol/mg protein) than in the five thyroid neoplasms with increased uptake (0.19 pmol/mg) (P = 0.055). Compared with the original carcinoma tissues, TSH binding revealed a reduced binding affinity in eight out of eleven metastases. Two metastases showed a complete absence of TSH binding, suggesting that they were not dependent on TSH for growth. We conclude that one class of TSH-binding site is predominant in normal dog thyroid tissues and dog thyroid carcinomas. TSH could therefore contribute, at least in theory, to further growth of primary dog thyroid carcinomas. Secondly, assays measuring TSH binding may not be able to discriminate between malignant and benign dog thyroid tumours. TSH receptor number or affinity may be related to the functional variability of thyroid neoplasms.(ABSTRACT TRUNCATED AT 250 WORDS)

Flow-cytometric DNA ploidy analysis in primary and metastatic canine thyroid carcinomas

DNA ploidy was measured by flow cytometry in 36 primary malignant thyroid neoplasms (including 6 bilateral tumours which were considered as separate neoplasms) from 30 dogs. In addition, DNA ploidy was determined in local recurrences in 3 dogs, and in 18 metastatic sites from 14 dogs. Aneuploidy was found in 21 of 36 (58%) primary sites. Eighteen of the 21 (86%) aneuploid tumours contained hypodiploid cell populations, with 12 having single hypodiploid peaks, and 6 being multiploid. Three other tumours had single aneuploid peaks with a DNA index (DI) greater than 1.0. The DIs in local recurrences were identical to those in the original neoplasms. Ploidy status (diploid vs. aneuploid) was identical in primary and metastatic sites in 10 out of the 14 dogs. Aneuploidy was more frequent in carcinomas from dogs with distant metastases (78%) than from dogs with less advanced stages of disease (53%), although this difference was not significant. There was no significant correlation between DNA ploidy and histopathological variables. From the strikingly high frequency of hypodiploidy in canine tumours, it is concluded that ploidy evolution in canine neoplasms may differ from that in human tumours.

Circulating thyroglobulin measurements by homologous radioimmunoassay in dogs with thyroid carcinoma

Circulating thyroglobulin was measured in 20 dogs with thyroid cancer, using a homologous polyclonal radioimmunoassay. Plasma Tg levels exceeded the normal range in 14 (70%) dogs, and ranged from 6 to 2902 micrograms/l (median 608). Plasma Tg levels tended to decrease from follicular carcinomas to solid-follicular carcinomas, to solid carcinomas (p less than 0.05). Plasma Tg levels were also higher in scintigraphically hot tumours than in cold ones. Other relationships between circulating Tg and clinical, pathological, and functional parameters were not found, except a poor (R = 0.49) but significant (p = 0.04) correlation between Tg and T4 levels. Plasma Tg was measured before surgery and at least once during follow-up, in 9 dogs. After hemithyroidectomy, a decrease was observed in 8 dogs. In 7 of these 8 dogs, plasma Tg levels declined within the reference range at the first postoperative sample. In the ninth dog, where metastases were detected 14 months after surgical treatment, plasma Tg slightly increased, yet within normal range. It is concluded that measurement of plasma Tg levels might be useful for monitoring the postoperative course of the disease in individual dogs with thyroid cancer.

Caprine peripheral neuroblastomas: structural and ultrastructural features, intermediate filaments profile and neuro-endocrine characterization

In this report the morphological and immunohistochemical features with respect to intermediate filament proteins and the neuroendocrine nature of bilateral neuroblastomas possibly originating from the adrenal medulla in a goat kid are presented. Histologically, the tumours were composed of small, round, blue cells organized in highly cellular nests and sheets separated by fibrovascular septa. Isolated cells mimicking the morphological features of neurones were observed in both tumours. Ultrastructurally, dense-core neurosecretory granules, about 100 nm in diameter, and irregularly organized neurotubular networks were seen. The small tumour cells were only labelled by vimentin, while the neurone-like cells were labelled by both neurone-specific enolase and synaptophysin. The lack of staining of the tumour cells by the neurofilament proteins antiserum, which was also observed in a human neuroblastoma (used as positive control) has been previously reported and is probably the result of the tissue processing and/or the poor differentiation stage of the tumours. The vimentin labelling of tumour cells could be explained by the poor differentiation stage of the tumours, since vimentin is the only intermediate filament protein in presumptive neuroblasts, being replaced by neurofilament proteins in later stages of neurogenesis.

[Veterinary pathology: a vital specialism within veterinary medicine]

Pathology is by definition an entity of major importance in medical science. Within medical care, pathologists are involved in cytopathological, histopathological and post mortem examinations. The value of post mortem examinations is discussed with reference to the value of the autopsy within human medical science. In veterinary medicine, veterinary pathology has to be incorporated in highly qualified veterinary medical care, has to participate in the quality assessment and the quality control of veterinary medical care, and has to be involved in the required continuing education of veterinarians. In addition, veterinary pathology is involved in basic research and research with regard to human health control.

[Tumor cells and extracellular matrix with special reference to mamma tumors in dogs and cats]

The essence of the cell-matrix interaction in tissues is that cells influence the composition of the extracellular matrix but that, on the other hand, components of the matrix are also involved in the regulation of growth and differentiation of the cells. Interaction is also found to occur in tumours though in a different way, so that infiltration and metastasis and the occurrence of scirrhous carcinomas are the result. Canine and feline mammary tumours are interesting objects for the study of this interaction since fibroadenomatous changes, in which connective tissue is the predominating tissue, is a common finding in cats only, whereas mixed and complex mammary tumours, producing matrix components of varying type, are common tumours in dogs.

The use of keratin antisera in the characterization of a feline thymoma

A cystic mass in the anterior mediastinum of a 9-year-old female European Shorthair cat was classified as a lymphocytic thymoma based on its histopathological features which were in accordance with those reported in the literature concerning feline thymomas. The application of a polyclonal keratin antiserum and monoclonal keratin antisera RCK 102, RKSE 60 and RGE 53 resulted in staining of foetal feline thymic cells, oesophageal epithelial cells as well as numerous stellate tumour cells and Hassall's corpuscles. As a result, the epithelial origin of the neoplastic cells could be established and the classification of thymoma confirmed. The results indicate the value of keratin antisera in the differentiation of thymoma and non-epithelial tumours in the anterior mediastinum.