Evaluation of clinical pathology parameters in fecal PCR-positive or PCR-negative goats for Johne's disease.

Johne's disease (JD) is an economically important infectious disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). This study evaluated the differences in various hematological and biochemical parameters between healthy goats and goats with JD. Forty goats were chosen randomly from a herd endemic for JD. A complete physical examination was performed. Blood and fresh fecal samples were collected from each goat. A complete blood cell (CBC) count and a protein electrophoresis were performed. Polymerase chain reaction (PCR) on fecal samples was performed in order to divide goats into two groups: group A "positive PCR on feces"; and group B "control (negative)." A Student's t test was performed for each parameter to verify differences between groups A vs B. Twenty goats were included in each group. Clinical signs likely related to JD were found in the history of 4/40 (10%) goats, while 36/40 (90%) goats were reported to be asymptomatic. CBC and electrophoresis values were within reference intervals in both groups. No differences were found for CBC parameters between the two groups. Values for alpha 1, beta, gamma globulins, and total protein (TP) were statistically higher in group A vs those in group B, while those for albumin and albumin/globulin (A/G) ratio were lower. An increase in TP, hypoalbuminemia, and hypergammaglobulinemia has been reported in group A, while no abnormalities were found concerning CBC. JD-positive goats seem to show earlier clinical pathological alternations than clinical signs. Protein electrophoresis may help the diagnosis of JD in asymptomatic goat herds, acting as an economical screening method.

Protein Expression of Canine and Feline Muscular Dystrophies.

Muscular dystrophies in dogs and cats represent a heterogeneous group of inherited, sometimes congenital, but infrequently diagnosed, progressive neuromuscular disorders. A correct identification and characterization of canine and feline muscular dystrophies could increase diagnostic and treatment strategies for veterinary neurologists and could identify useful animal models for the study of human dystrophies. However, in dogs and cats, diagnosis of muscular dystrophies is challenging due to a nonspecific clinical phenotype and pathological lesions, thus is most likely underestimated. We performed immunofluorescence and Western blot techniques using a wide panel of antibodies against proteins involved in human dystrophies (dystrophin mid-rod and carboxyterminal domain, α, ß, γ, and δ-sarcoglycan, α-dystroglycan, caveolin-3, emerin, merosin, dysferlin, calpain-3, spectrin epitopes), on 9 canine and 3 feline muscle biopsies characterized by myopathic changes. Dystrophin deficiency was detected in 3 dogs and 2 novel canine muscular dystrophies have been identified, characterized by deficiency of caveolin-3 and calpain-3, respectively. In 2 cats, deficiency of ß-SG and carboxyterminal domain of dystrophin in all muscle fibers has been detected. Performing immunofluorescence and Western blot analyses with a wider panel of antibodies allowed a correct identification of muscular dystrophies in dogs and cats and provides a direction for subsequent targeted genetic testing.

Polyarteritis Nodosa in a Cat with Involvement of the Central and Peripheral Nervous Systems.

An 18-month-old neutered male domestic shorthair cat was referred with a history of pyrexia, polyuria and polydypsia, and transient episodes of bilateral hindlimb paralysis. Cardiac evaluation revealed severe systemic hypertension and severe concentric hypertrophy of the left ventricle. One month later the cat had a new episode of hindlimb paralysis with recurrent seizures, and died in status epilepticus. At necropsy examination, the coronary arteries, arcuate renal arteries and common iliac arteries showed marked thickening with nodules segmentally located along the vessels and consequent narrowing of the lumina. Histologically, acute and chronic inflammatory infiltration of the vascular walls was associated with necrosis of the muscular layer. Lesions were consistent with polyarteritis nodosa and involved the small, medium and large arteries of the heart, kidneys, small and large intestine, mesentery, liver and thyroid. Multifocal meningeal vasculitis associated with focal infarction of the frontal lobe and necrotizing vascular polyneuropathy were detected. Involvement of the central and peripheral nervous systems in polyarteritis nodosa is a novel finding in cats.

Protothecal granulomatous meningoencephalitis in a dog.

A case of central nervous system protothecosis in a dog is reported. A three-year-old male Maremma sheepdog was referred with a two month history of diarrhoea associated with progressive tetraparesis, depression and right circling. Stupor, severe proprioceptive deficits, bilateral decreased thoracic limb flexor reflexes and bilateral deficit of the menace reaction were detected on neurological examination and a multi-focal neurological localisation was suspected. Histopathological evaluation revealed multi-focal granulomatous foci in the thalamus, hippocampus and caudal brainstem containing numerous oval-rounded organisms with a thick, periodic acid-Schiff-positive and Gomori's methenamine silver-positive cell wall, a basophilic cytoplasm and one nucleus. Scattered sporangia containing two to four endospores were also observed. Morphological features were consistent with Prototheca species. Ultrastructurally, numerous degenerated algae were present within macrophages mainly lacking nuclei and cytoplasmic organelles. Generally, protothecosis in dogs is characterised by systemic signs because of a multi-organ involvement, and haemorrhagic colitis or ophthalmologic signs are the most frequent presenting signs. However, protothecosis should be added, also in Europe, to the list of the differential diagnoses in adult dogs with a multi-focal neurological localisation even in absence of other clinical signs.

Magnetic resonance imaging and pathological findings in a case of canine idiopathic eosinophilic meningoencephalitis.

A case of idiopathic eosinophilic meningoencephalitis in a six-month-old male Maremma shepherd dog is reported. The dog was referred with a four month history of progressive weakness and depression with loss of trained habits. Tendency to recumbency, disorientation, visual impairment, bilaterally decreased menace response and hindlimb conscious proprioception deficits were detected. Magnetic resonance imaging showed a diffuse hypointense signal involving the cerebral grey matter with enlargement of the cerebral sulci on T1-weighted and fast fluid-attenuated inversion recovery (FLAIR) sequences consistent with a diffuse necrosis or atrophy of the cortical grey matter. Histological examination revealed severe inflammatory infiltration mainly composed of eosinophils and macrophages in the subarachnoid space and in the superficial layer of the cerebral cortex where parenchymal rarefaction and necrosis of neurones were also evident. No parasites, cysts or fungi were detected, and an immunologically mediated disorder was suspected. Magnetic resonance imaging may represent a useful diagnostic tool to differentiate idiopathic eosinophilic meningoencephalitis from other inflammatory brain diseases of young dogs.

Semilobar Holoprosencephaly Associated with Multiple Malformations in a Foal.

A full-term male foal born in a farm holidays in Maremma (Tuscany, Italy) was euthanized shortly after birth due to the presence of several malformations. The rostral maxilla and the nasal septum were deviated to the right (wry nose), and a severe cervico-thoracic scoliosis and anus atresia were evident. Necropsy revealed ileum atresia and agenesis of the right kidney. The brain showed an incomplete separation of the hemispheres of the rostral third of the forebrain and the olfactory bulbs and tracts were absent (olfactory aplasia). A diagnosis of semilobar holoprosencephaly (HPE) was achieved. This is the first case of semilobar HPE associated with other organ anomalies in horses.

Clinicopathological features of globoid cell leucodystrophy in cats.

Clinical and pathological findings consistent with globoid cell leucodystrophy (GLD) were evaluated in two domestic shorthaired cats, aged 3 and 4 months. Both showed neurological signs mainly characterized by progressive pelvic limb ataxia, paraplegia with loss of deep pain perception in the pelvic limb, and intentional tremors of the thoracic limbs. Pathological changes affecting the central and peripheral nervous systems were characterised by diffuse, bilateral and symmetrical myelin loss, and marked astrogliosis. In the leucodystrophic areas there was perivascular accumulation of large PAS-positive, non-metachromatic macrophages (globoid cells), with intracytoplasmic accumulation of crystalloid tubular aggregates. Peripheral nerves showed demyelinating features with thin myelin sheaths, myelin splitting, and ballooning; the nerve fibres had bizarre shapes due to the presence of pale inclusions in the Schwann cells. GLD in cats shares clinical and pathological features with the disease described in other animals and human beings. The neurological signs differed from those of other feline inborn neurometabolic diseases and cerebellar hypoplasia.

Apoptosis in the mammalian CNS: Lessons from animal models.

It is generally assumed that about half of the neurons produced during neurogenesis die before completion of maturation of the central nervous system (CNS). Neural cell death is also relevant in aging and several neurodegenerative diseases. Among the modalities by which neurons die, apoptosis has very much attracted the interest of investigators because in this type of cell death neurons are actively responsible for their own demise by switching on a number of genes and activating a series of specific intracellular pathways. This review focuses on the cellular and molecular mechanisms of apoptosis in normal and transgenic animal models related to naturally occurring neuronal death within the CNS. We will also consider some examples of apoptotic cell death in canine neuropathologies. A thorough analysis of naturally occurring neuronal death in vivo will offer a basis for parallel and future studies involving secondary neuronal loss such as those in neurodegenerative disorders, trauma or ischaemia.

Meningeal carcinomatosis in two cats.

Multifocal to diffuse meningeal infiltration by neoplastic epithelial cells was observed in two aged cats with neurological signs and a history of surgical ablation of the auricular pinnae because of the presence of squamous cell carcinoma. In both cats, examination of the external ear canals revealed neoplastic lesions consistent with squamous cell carcinoma, but no changes of the tympanic bullae were noted. In one cat, post-mortem examination revealed marked thickening of the dura mater and infiltration of the arachnoid layer by cytokeratin-positive, neoplastic epithelial cells. In the other cat, no macroscopic brain lesions were noted, but multifocal dissemination of neoplastic epithelial cells to the leptomeninges was observed histologically. Several pathways by which neoplastic cells can reach the meninges have been suggested and haematogenous dissemination was considered most likely in these cats. Squamous cell carcinoma is the most common cutaneous malignant neoplasm in cats and meningeal carcinomatosis can be considered a rare complication.

Pathological and immunohistochemical studies of choroid plexus carcinoma of the dog.

Choroid plexus carcinomas in four dogs (three male, one female) aged small middle 2.5 to 10 years, were examined by light microscopy and immunohistochemistry. The dogs showed progressive neurological signs including ataxia, seizures, vestibular disease and cranial nerve deficits, lasting for several months in some cases. Primary tumours were localized in the lateral (one case), third (one case), and fourth (two cases) ventricles. Hydrocephalus was evident at post-mortem examination in one case. In two cases the neoplastic cells closely resembled the structure of normal choroid plexus, with a distinct papillary pattern, composed of well-differentiated columnar epithelium. In the other two cases, cellular pleomorphism, nuclear atypia, increased mitotic activity and necrosis were observed. In all cases, dissemination of neoplastic cell clusters was detected within the subarachnoid space or the ventricular cavity. Immunohistochemical examination showed a multifocal labelling pattern for pankeratin and cytokeratin AE1 and diffuse vimentin positivity in poorly differentiated tumours. Well-differentiated choroid plexus carcinomas showed multifocal immunoreactivity for cytokeratin AE3, multifocal to diffuse immunoreactivity for vimentin and occasional positivity for carcinoembryonic antigen. Epithelial membrane antigen, Ber EP4 and S-100 were negative in all cases. Glial fibrillary acidic protein labelling occurred only in a single, poorly differentiated tumour. Occasional reactions for proliferating cell nuclear antigen and MIB-1 were seen in two cases. It was concluded that at least two morphological and possibly phenotypic subtypes (well-differentiated and anaplastic) of choroid plexus carcinoma of the dog could be identified.

Clinical and neuropathological features of West Nile virus equine encephalomyelitis in Italy.

West Nile (WN) virus infection is a mosquito-borne flavivirosis endemic in Africa and Asia. Clinical disease is usually rare and mild and only in a few cases the infection causes encephalomyelitis in horses, fever and meningoencephalitis in man. We report here the clinical and pathological findings in an epidemic of the disease involving 14 horses from Tuscany, Italy. All cases were observed from August to October 1998. Affected horses showed ataxia, weakness paresis of the hindlimbs and, in 6 cases, there was paraparesis progressing to tetraplegia and recumbency within 2 to 9 days. Eight animals recovered without any important consequences. Serological investigations revealed positivity to WN virus in all the 14 horses and the agent was isolated from the cerebellum and spinal cord of an affected horse. Postmortem examination was carried out on 6 horses. The neuropathological pattern was that of a mild to moderate, nonsuppurative polioencephalomyelitis with constant involvement of the ventral horns of the thoracic and lumbar spinal cord, where focal gliosis and haemorrhage were also apparent in some cases. Differential diagnoses with other equine viral encephalomyelitides are discussed. Climatological and environmental characteristics of the geographic area in which the outbreaks occurred suggest the existence of suitable conditions for the development of the disease. This is the first report of WN virus equine encephalomyelitis in Italy.

Diagnosis of paratuberculosis in naturally infected goats.

A survey was carried out to verify if an immunohistochemical method associated with agar gel immunodiffusion (AGID) will establish a firm diagnosis of caprine paratuberculosis. One hundred and thirty-six goats were tested by AGID for antibodies against Mycobacterium avium subsp. paratuberculosis at two different times: the first time 22 (19.1%) were positive and the second time 25 (18%). One seronegative goat with severe diarrhea and 5 seropositive goats, two of which showing similar clinical signs, were sacrificed and necropsied. Samples were taken from small intestine, liver, spleen, mesenteric lymph nodes for bacteriological, histological and immunohistochemical examinations. M.a. paratuberculosis was isolated from intestine samples of 4 seropositive goats and from mesenteric lymph nodes of one seropositive goat; the microorganism was not isolated from samples of one seropositive and the seronegative animals. Ziehl Neelsen staining showed acid-fast bacilli in macrophages of the 5 seropositive animals and the immunohistochemical method for M. a. paratuberculosis detected bacterial antigen in the same samples.

[Stenosis complications in digestive surgery: a histomorphological contribution. Comparison of mechanical and manual sutures]. / La "complicanza stenosi" in chirurgia digestiva: un contributo istomorfologico. Suture meccaniche e manuali a confronto.

BACKGROUND: Surgeons variously estimate usage of mechanical staplers in digestive surgery especially about the increase of the incidence of late complications like stricture (as some authors refer). We report a histomorphological aid to the comparison of staplers and hand-sewn sutures. Our aim was to observe at long term the healing process in the sutured tissue in the canine gastro-enteric tract. METHODS: We describe three histological pieces: one manual suture in a dog which was euthanatized and necropsied 5 months after operation and two mechanical sutures performed in two different dogs: one died because of a gastric torsion 18 months after the operation while the other was euthanatized 5 months after the operation. The histomorphological study has been carried out with a peculiar cutting (Exact) and including method which lets the staples in situ. RESULTS AND CONCLUSIONS: Compared analysis showed that cicatrization goes on better in stapled than in hand sutured tissue.

Survey of canine and feline follicular tumours and tumour-like lesions in central Italy.

Between January 1985 and June 1997, a total of 4005 skin biopsies were received from dogs and 898 from cats. Follicular tumours and tumour-like lesions together represented 10.4 per cent and 8.1 per cent of all skin tumours in the dog and cat, respectively. The prevalence of tumour-like lesions, such as follicular and dermoid cysts, dilated pore and focal adnexal dysplasia, was highest, representing 41.2 per cent and 68 per cent of all follicular lesions in dogs and cats, respectively. In the dog, follicular tumours were distributed as follows: trichoblastoma (25.6 per cent of all tumours and tumour-like lesions), infundibular keratinising acanthoma, (14 per cent), pilomatricoma (13 per cent), trichoepithelioma (3.9 per cent) and tricholemmoma (2.3 per cent). In the cat, the distribution was 26 per cent for trichoblastoma, 4 per cent for trichoepithelioma and 2 per cent for pilomatricoma. Tumour-like lesions and infundibular keratinising acanthoma in the dog were mostly located on the trunk, trichoblastoma and tricholemmoma on the head, and pilomatricoma on the neck. In the cat, both tumour-like lesions and trichoblastoma were frequently present on the neck and head.

Pathogenesis of scrapie in ARQ/ARQ sheep after subcutaneous infection: effect of lymphadenectomy and immune cell subset changes in relation to prion protein accumulation.

It is well established that the infectious agent of scrapie can replicate in the lymphoreticular system (LRS). However, the effects of removal of LRS target tissues on the pathogenesis of the infection and the accumulation of disease-associated prion protein (PrP(d)) in LRS tissues on specific immune cell subsets are poorly understood aspects. To address these questions 16 ARQ/ARQ sheep were subcutaneously inoculated in the drainage area of the prefemoral lymph node with brain homogenate derived from Suffolk sheep naturally infected with scrapie. Fourteen sheep were then subjected to either early (14-17 days post-inoculation [dpi]) or late (175-201 dpi) lymphadenectomy and culled at preclinical or clinical stages of infection. Neither late nor even early lymphadenectomy prevented infection or had any effect on the accumulation of PrP(d) in the LRS or CNS suggesting a rapid organic dissemination of the infectious agent after inoculation. Lymph nodes from eight scrapie inoculated sheep selected on the basis of the amount of PrP(d) in their LRS tissues (negative, low or high) were examined for six different immune cell markers. The PrP(d) negative lymph nodes from two sheep with no evidence of scrapie infection showed lower numbers of cluster of determination (CD) 21 positive cells than PrP(d) positive nodes, irrespective of their location (hind leg or head). However, quantitative differences in the expression of this marker were not detected when comparing lymph nodes with low and high levels of PrP(d) accumulation, suggesting that proliferation of CD21 positive cells is related to scrapie infection, but not directly linked to the magnitude of PrP(d) accumulation. An additional observation of the study was that sheep that were methionin-threonine at codon 112 of the prion protein gene showed lower attack rates than methionine homozygotes (67% and 100%, respectively) and also generally lower levels of PrP(d) accumulation in the LRS and brain and increased survival times, suggesting an influence of such polymorphism in the susceptibility to scrapie.

Adult-onset muscular dystrophy in a cat associated with a presumptive alteration in trafficking of caveolin-3.

A 10-year-old neutered female domestic longhaired cat was referred for evaluation of forelimb weakness and lameness. There was hypertrophy and firmness of the musculature with no neurological deficits. Moderate increase of creatine kinase activity was present. Muscle biopsy showed rounded atrophic and hypertrophic fibres, an increased number of centrally located myofibre nuclei, scattered rimmed vacuoles and mild perimysial and endomysial fibrosis. Myofibre necrosis with phagocytosis was present in the gluteal muscle. Immunohistochemistry revealed absence of sarcolemmal caveolin-3 in almost all muscle fibres and sarcoplasmic accumulation of the protein in approximately 30% of myofibres. Normal expression of caveolin-3 was detected by immunoblotting, so protein mislocalization in the sarcoplasm due to aberrant trafficking towards the sarcolemma was suspected. This case represents the first example of muscular dystrophy due to a caveolinopathy in animals.

Clinical diagnosis of West Nile Fever in Equids by classification and regression tree (CART) analysis and comparative study of clinical appearance in three European countries.

This retrospective study describes risk/protection factors for the development of clinical West Nile Fever (WNF) in equids, compares clinical presentation in three European countries, France, Italy and Hungary, and creates classification and regression trees (CART) to facilitate clinical diagnosis. The peak of WNF occurrence was observed in September whatever the country. A significant difference between Italy and France was observed in the delay between initial clinical signs and veterinary consultation. No clinical sign was significantly associated with WNF. Despite similar clinical presentations in the three countries, occurrence of hyperthermia was more frequently reported in France. Classification and regression tree demonstrated the major importance of geographical locality and month to reach a diagnosis and emphasized differences in predominant clinical signs depending on the period of detection of the suspected case (epizootic or not). However, definite diagnosis requires specific serological tests. Centralized reporting system and time-space risk mapping should be promoted in every country.

Muscular dystrophy with reduced beta-sarcoglycan in a cat.

A partial beta-sarcoglycan (SG) deficiency with retention of other components of the SG complex (SGC) is described in 6-month-old, intact male domestic shorthaired kitten that was referred for evaluation of weakness, reluctance to move and dyspnoea. Neurological deficits were restricted to the neuromuscular system. Muscle biopsy revealed moderate variability in myofibre size, with numerous atrophic rounded fibres, rare myofibre necrosis, regeneration and moderate perimysial and endomysial fibrosis. Immunohistochemistry revealed decreased expression of beta- and gamma-SG and western blotting revealed markedly decreased beta-SG with normal expression of alpha-, gamma- and delta-SG, caveolin-3 and calpain-3. Sarcoglycanopathy has not previously been described in cats. In human and canine sarcoglycanopathies the deficiency in any one of the SGs leads to secondary deficiency of the entire SGC. Such spontaneously arising muscular disease in animals can provide valuable models for equivalent human disorders.

Neuropathology of italian cats in feline spongiform encephalopathy surveillance.

Feline spongiform encephalopathy (FSE) is a transmissible spongiform encephalopathy associated with the consumption of feedstuffs contaminated with tissue from bovine spongiform encephalopathy-affected cattle and characterized by the accumulation in the central nervous system of an abnormal isoform of the prion protein (PrP(sc)). Clinically, it presents as a progressive fatal neurologic syndrome that is not easily distinguished from other feline neurologic conditions. Most cases of FSE have been reported in England, where it was first detected in 1990, but a few cases have been reported from other European countries. To identify possible cases of FSE in Italy, the Italian Ministry of Health funded a 2-year surveillance project during which the brains from 110 domestic cats with neurologic signs were evaluated histologically for spongiform encephalopathy and immunohistochemically to detect PrP(sc). Although no cases of FSE were found, the study proved useful in monitoring the Italian cat population for other neurologic diseases: neoplasia (21.8%), toxic-metabolic encephalopathy (18.2%), granulomatous encephalitis (15.5%), suppurative encephalitis (4.6%), trauma (3.6%), circulatory disorders (3.6%), degeneration (2.7%), nonsuppurative encephalitis (2.7%), and neuromuscular diseases (1.8%). No histologic lesions were found in 20% of the brains, and samples from 5.5% of the cats were rejected as unsuitable.