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1.
A 5-month-old Angus heifer with a history of acute hindlimb paresis that quickly progressed to lateral recumbency was necropsied. Gross lesions included a 6-cm segment of gray to brown discoloration and softening of the right ventrolateral spinal cord between T2 and T3. Microscopically, there was liquefactive necrosis of ventrolateral white and gray matter, and multiple intravascular emboli partially or completely occluded many intralesional and adjacent spinal and meningeal arteries and veins. Emboli were alcian blue positive, consistent with fibrocartilage of the nucleus pulposus of the intervertebral disk. No gross abnormalities were detected in the vertebrae or intervertebral disks. Fibrocartilaginous embolic myelopathy appears to be very rare in cattle; however, it should be considered in cases of acute, nonprogressive spinal cord dysfunction.  相似文献   

2.
OBJECTIVE: To identify and describe the occurrence of neurological lesions that could have an effect on lamb mortality. PROCEDURE: The central nervous system was investigated macroscopically (n = 92) and microscopically (n = 72) in lambs dying in the perinatal period during 3 years in flocks of adult Corriedale ewes. The central nervous system was removed intact and samples of cerebral cortex, basal ganglia, thalamus, hippocampus, mesencephalon, cerebellar cortex, medulla oblongata, and cervical spinal cord were scored microscopically for the severity of neuronal dead, cytotoxic and perivascular oedema, and haemorrhage. RESULTS: Neurologic findings between birth and 6 days included haemorrhages in meninges, brain congestion and oedema, neuronal ischemic necrosis, intraparenchymal haemorrhages in medulla oblongata and cervical spinal cord, parasagittal cerebral necrosis, and periventricular leukomalacia. No significant lesions were found in anteparturient deaths or in those aged between 7 and 16 days. Oedema was more severe in the brain than in other regions of the central nervous system. Ischaemic neurons first appeared 24 hours post partum, increased linearly in number between 48 hours and 5 days post partum, and had a laminar distribution in the cerebral cortex, indicating a hypoxic-ischemic encephalopathy. Haemorrhages were most severe in the gray matter of medulla oblongata and cervical spinal cord, suggesting trauma due to instability of atlantoaxialis joint. CONCLUSION: Lesions in the central nervous system can explain most deaths at birth and within 6 days of birth. The lesions were hypoxic-ischemic and appeared to be related to birth injury.  相似文献   

3.
Aseptic and noninfectious diseases of the central nervous system are being recognized with increasing frequency. After multiple episodes of neurologic illness, this 7-year-old Weimaraner dog was euthanatized and submitted for postmortem examination. Lesions in the central nervous system were found mainly in the white matter of the cerebral cortex and cervical spinal cord and represented acute and more chronic injury. Necrotizing vasculitis with fibrinoid change and a marked neutrophilic infiltrate dominated the acute lesions. More chronic changes consisted of perivascular demyelination and accumulation of foamy macrophages with positive staining for myelin. An immune-complex (Arthus-type) vasculitis is suspected.  相似文献   

4.
A progressive neurological disease affecting twenty-two young adult dogs of smaller breeds is reported. The disease was most often acute in onset and the neurological signs included cervical pain, seizures, behavioural changes, ataxia, head tilt, muscle tremor and paresis. The lesions were those of a disseminated granulomatous meningoencephalomyelitis in which perivascular cuffs of macrophages and lymphoid cells were the predominant finding. Severe lesions were most often seen in the cerebral white matter although the brain stem, mid-brain and spinal cord were also commonly affected.  相似文献   

5.
After being anaesthetised for between one hour 40 minutes and seven hours, five adult horses developed acute neurological signs and extensive cerebrocortical necrosis. Four of them had had abdominal surgery for colic and one had had repeated orthopaedic interventions. Between five hours and seven days after the surgery, all five horses suddenly developed severe signs of a predominantly prosencephalic disturbance: bilateral blindness with normal pupillary light responses, abnormal behaviour varying from propulsive pacing to head pressing profound lethargy and generalised seizures. They were euthanased between 24 hours and three weeks after the onset of these signs. In three of the cases a gross examination of the brain revealed patchy malacia of the cerebral grey matter and some discolouration of the adjacent white matter. Microscopical examination revealed lesions that varied from laminar neuronal necrosis in the grey matter of the cerebral cortex to more diffuse necrosis of the cortex and underlying white matter. Four of the five cases had had a period of hypercapnea while anaesthetised, and two of them (and possibly a third) had also had hypoxaemia.  相似文献   

6.
Gross changes and other necropsy findings in 36 purebred Brown Swiss cattle affected with bovine progressive degenerative myeloencephalopathy were nonspecific. Primary microscopic lesions were confined to the central nervous system, specifically the white matter of the spinal cord, axons in some brainstem nuclei, and Purkinje cells of the cerebellar cortex. Spinal cord lesions involved only the white matter and consisted of axonal degeneration, loss of axons and myelin, and status spongiosus. Axonal degeneration was characterized by swelling and fragmentation of the axoplasm or formation of large, discontinuous swellings referred to as spheroids. Lesions were qualitatively similar at all levels, but quantitatively dissimilar in the same funiculi at different levels. Both ascending and descending fibers were involved but correlation to specific fasciculi was not evident. Lesions always were most severe in thoracic spinal cord segments. Little or no astroglial response, no inflammatory response, and no involvement of gray matter were observed in the spinal cord. Cerebellar lesions were limited to selective degeneration and loss of Purkinje cells and occasional swelling of Purkinje cell axons (torpedos) in the granular layer of the cerebellar cortex. Brainstem lesions were inconsistent and limited to occasional axonal swelling in brainstem nuclei. The pathogenesis of bovine progressive degenerative myeloencephalopathy is unknown and possible mechanisms were discussed. The disease exhibits a familial pattern in Brown Swiss cattle and may be hereditary. Extraneural lesions were considered secondary to central nervous system lesions.  相似文献   

7.
Spinal cord nematodiasis epidemiologically, clinically, and histologically consistent with Parelaphostrongylus tenuis infection was noted in two flocks of sheep. Spinal cords from two sheep with active infection and one from a partially recovered animal were studied in an effort to determine the sequence of lesions following larval invasion of the central nervous system. In the former two sheep, migration of larvae within the spinal cord induced asymmetrically irregular tracks of disrupted and necrotic tissue, primarily in white matter. Subsequently, macrophages infiltrated these regions and phagocytized the necrotic tissue, which led to cavity formation. Swelling and loss of axons, diminished myelin staining, mononuclear cell infiltration and increase in astrocytic fibers were often seen in adjacent tissue. Only occasional coiled larvae were found in these actively infected animals. Late stage lesions in the white matter in the partially recovered sheep included multiple small astrogliotic regions with diminished myelin and axonal content, and a single large multicavitary, atrophic, gliotic zone.  相似文献   

8.
CASE DESCRIPTION: A 6.5-year-old female eastern black and white colobus monkey (Colobus guereza) was evaluated after acute onset of ataxia and inappetence. CLINICAL FINDINGS: The monkey was ataxic and lethargic, but no other abnormalities were detected via physical examination, radiography, or clinicopathologic analyses. During the next 2 days, the monkey's clinical condition deteriorated, and its WBC count decreased dramatically. Cytologic examination of a CSF sample revealed marked lymphohistiocytic inflammation. TREATMENT AND OUTCOME: Despite supportive care, the monkey became apneic; after 20 hours of mechanical ventilation, fatal cardiac arrest occurred. At necropsy, numerous petechiae were detected within the white matter tracts of the brain; microscopic lesions of multifocal necrosis and hemorrhage with intranuclear inclusions identified in the brain and adrenal glands were consistent with an acute herpesvirus infection. A specific diagnosis of herpesvirus papio-2 (HVP-2) infection was made on the basis of results of serologic testing; PCR assay of tissue specimens; live virus isolation from the lungs; and immunohistochemical identification of the virus within brain, spinal cord, and adrenal gland lesions. Via phylogenetic tree analysis, the colobus HVP-2 isolate was grouped with neuroinvasive strains of the virus. The virus was most likely transmitted to the colobus monkey through toys shared with a nearby colony of baboons (the natural host of HVP-2). CLINICAL RELEVANCE: To the authors' knowledge, this is the first reported case of natural transmission of HVP-2 to a nonhost species. Infection with HVP-2 should be a differential diagnosis for acute encephalopathy in primate monkeys and humans, particularly following exposure to baboons.  相似文献   

9.
Discrete foci of white matter necrosis were observed in the telencephalic white matter in 6 cases of spontaneous ovine abortion. All fetuses were in the third trimester of gestation and 2 of the 6 were term fetuses. The lesions were distributed randomly throughout the cerebrocortical white matter and consist of pale hypocellular plaques with a variable glial cell response and encrustation of necrotic cellular processes. A variety of additional lesions were present in the brains of the aborted fetuses. The lesions of telencephalic white matter necrosis have not been reported previously and are unlike those associated with known viral infections of the developing fetus. Based on the character of the lesions, a hypoxic-ischemic or hypotensive mechanism is suggested. The lesions are compared with a similar condition in human fetuses and neonates.  相似文献   

10.
A 12-year-old intact female llama was euthanized following acute onset of spastic tetraparesis and recumbency with inability to rise. Postmortem examination revealed caudal cervical spinal cord compression due to a mass within the ventral spinal canal arising from the C6-C7 intervertebral disk space and attached to an irregularly thickened annulus fibrosis. On histopathologic examination, the mass was composed of amorphous acellular basophilic to amphophilic material admixed with irregularly arranged collagen bundles. The amorphous material was metachromatic and contained multiple small foci of markedly vacuolated round cells, characteristic of origin from the nucleus pulposus. Severe necrosis of all white matter tracts with astrocytic reaction was present in the overlying spinal cord segment. Ascending and descending Wallerian degeneration and dissecting interstitial astrogliosis were present within white matter tracts above and below the lesion, respectively. The diagnosis was compressive myelopathy due to chronic extrusion of the nucleus pulposus of the C6-C7 intervertebral disk. To the authors' knowledge, this is the first report of intervertebral disk disease in a camelid.  相似文献   

11.
Central European tick‐borne encephalomyelitis can be challenging to diagnose in dogs because the virus may not be detected in blood and cerebrospinal fluid (CSF) after the first viremic stage of the disease. The purpose of this retrospective case series study was to describe 3 Tesla magnetic resonance imaging (3T MRI) findings in a sample of dogs with a confirmed diagnosis of tick‐borne encephalomyelitis. Dogs were included if they had neurological signs consistent with tick‐borne encephalomyelitis, history of a stay in endemic areas for tick‐borne encephalomyelitis virus, 3T MRI of the brain and/or spinal cord, cerebrospinal fluid changes compatible with viral infection and positive antibody titers in cerebrospinal fluid or pathologic confirmation of tick‐borne encephalomyelitis. Twelve dogs met inclusion criteria. Ten out of 12 patients had 3T MRI lesions at the time of presentation. One patient had persistent lesions in follow‐up MRI. The 3T MRI findings included bilateral and symmetrical gray matter distributed lesions involving the thalamus, hippocampus, brain stem, basal nuclei, and ventral horn on the spinal cord. All lesions were hyperintense in T2‐weighted sequences compared to white matter, iso‐ to hypointense in T1‐weighted, nonenhancing, and had minimal or no mass effect or perilesional edema. Six patients survived while the remaining six dogs were euthanized. Necropsy revealed neuronophagia and gliosis of the gray matter of the affected regions seen in 3T MRI, in addition to the cerebellum. Findings from the current study indicated that tick‐borne encephalomyelitis should be included in the differential diagnosis list for dogs with the above described 3T MRI characteristics.  相似文献   

12.
Subacute meningoencephalitis or meningoencephalomyelitis caused by Streptococcus suis was diagnosed in 53 pigs over a four-year period. Affected pigs averaging 11 weeks of age with a range from five days to 26 weeks, had been treated with antibiotics and had partially recovered. Hyperemia of meningeal vessels and modest increase in cerebrospinal fluid were the most common gross central nervous system lesions. Histologically, fibrin, edema and a mixture of inflammatory cells were present in meninges and choroid plexus. Linear and perivascular infiltrates of neutrophils and mononuclear inflammatory cells invaded the brain and spinal cord and similar infiltrates were in lumina of ventricles and the spinal canal. Inflammatory cells also invaded the superficial layers of the brain directly from the overlying meninges. Bilateral subacute optic perineuritis and Gasserian ganglioneuritis also occurred. Segmental cortical necrosis of cerebellar folia characterized by degeneration, necrosis, neuronophagia and drop out of groups of Purkinje cells was a distinct lesion seen in 27 of the 53 pigs. Mild spongiosis of white matter in the cerebellum and brain stem accompanied these changes.  相似文献   

13.
A leukoencephalomyelopathy of rottweiler dogs   总被引：1，自引：0，他引：1  
Two adult rottweiler dogs were evaluated for slowly progressive ataxia and paresis of all four limbs of over seven months duration. On neurologic examination, signs referable to a lesion in the cervical spinal cord affecting motor and sensory white matter tracts were found. Both dogs were necropsied and were found to have demyelinating lesions in the spinal cord, brain stem, and deep cerebellar white matter. Primary morphologic alterations were intact naked axons and thinly myelinated axons accompanied by reactive astrogliosis. The spinal cord lesions tended to have bilateral symmetry and were found in the lateral funiculi and occasionally in the dorsal funiculi. The cause and pathogenesis of the lesion were not determined.  相似文献   

14.
A disorder of central nervous white matter in Norwegian-bred silver foxes is described from the case histories of 21 clinically affected foxes. The main presenting sign of this disorder was caudal limb ataxia, which appeared between 2 1/2 and 4 months of age and progressed over the next 4-8 weeks. Only four affected foxes were allowed to live beyond this period, but they showed moderate to marked improvement. Light microscopic examination of specimens from 16 affected foxes necropsied between 3 1/2 and 6 1/2 months of age revealed lesions that were restricted to the white matter of brain and spinal cord. The lesions were characterized by a symmetrical spongy change with vacuoles of varying sizes and included significant myelin deficiency. There was a relative preservation of axons and nerve cells and no significant inflammation or vascular reaction. An astrocytic hypertrophy was usually associated with the spongy change. Ultrastructural examination of central nervous tissue from two, perfusion-fixed, 6-month-old foxes showed intramyelin vacuoles resulting from splitting of the myelin lamellae at the intraperiod line and was interpreted as indicating myelin edema. Expanded extracellular spaces and watery astrocytic processes also contributed to the vacuolar appearance. Astrocytic processes in affected areas were hypertrophic and contained abundant filaments. Although the 16 silver foxes had severe clinical signs, their lesions had features in common with the juvenile form of Canavan's disease in children and a spongy degeneration reported in Labrador Retrievers; however, the clinical course in the foxes was not uniformly progressive.  相似文献   

15.
A central nervous system disease of mink occurred in three unrelated fur farms in Oregon in September, 1981. Only kits four to five months old were affected. Clinical signs consisted of posterior ataxia progressing to complete posterior paralysis with loss of motor control and sensation. Complete or partial recovery occurred in approximately 1.5 months in most mink. Microscopic lesions consisted of severe nonsuppurative meningoencephalitis and meningomyelitis with vacuolation of the white matter of the brain and spinal cord. Canine distemper virus infection and other recognized causes were ruled out on the basis of clinical signs, history, lesions, or laboratory findings. Experimental inoculations of mink with brain and spinal cord specimens from affected mink failed to reproduce the disease.  相似文献   

16.
A 24-day-old, 2.2-kg, female Reeves' muntjac (Muntiacus reevesi) acutely developed left hind limb lameness that resolved with rest and anti-inflammatory drugs but recurred at 8 mo of age. Magnetic resonance imaging (MRI) of the lumbar, sacral, and coccygeal spine revealed a fluid-filled dilatation of the central canal of the spinal cord, which was interpreted as a hydromyelic cyst. Surgical exploration and drainage of the cyst were attempted. Despite initially improved mobility, severe plantar ulceration of both hocks developed. The animal was euthanatized. Gross necropsy of the central nervous system revealed a 1.5-cm-long, mild depression with associated yellowing of the dorsal spinal cord in the lumbosacral region, dilatation of the central spinal canal that extended from the cranial thoracic spinal cord with diameter increasing caudally, and mild herniation of the brainstem at the foramen magnum. Histopathologic lesions of the central nervous system were restricted to the spinal cord, with equivocal enlargement of the fourth ventricle. Pathologic changes included irregular dilatation of the central canal, flattening to the absence of the ependymal cells, spongiosis of the gray matter neuropil, and dystrophic calcification. The gross and histologic findings confirmed the diagnosis of hydromyelia.  相似文献   

17.
A four-year-old, spayed female Yorkshire terrier was presented with a two-month history of lameness in the left forelimb, circling and falling. A magnetic resonance imaging (MRI) examination 11 days after presentation revealed dilation of the right lateral ventricle. Following euthanasia, which was performed about 10 months after the onset of clinical signs, there was gross evidence of degeneration and cavitation of the cerebrum and dilation of the lateral ventricle on the right side. Microscopically, cavitation and necrosis were observed in the white and grey matter of the right cerebrum and there was abundant gemistocytic and fibrillary astrocytosis. Haemorrhage and marked perivascular cuffing with mononuclear cells were found in the mesencephalon. Inflammatory lesions consisting of lymphocytic infiltration and glial proliferation were also present in the dorsal funiculus of the cervical spinal cord. This case was diagnosed as necrotising encephalitis in the Yorkshire terrier (NEYT) with involvement of the spinal cord. NEYT is a chronic progressive neurological disorder, resulting from widespread, destructive non-suppurative inflammation of the central nervous system of unknown cause. In the past decade, 12 cases have been documented in adult to aged Yorkshire terriers. Computed tomography and MRI can detect the characteristic multifocal cavitations and ventriculomegaly, facilitating premortem diagnosis.  相似文献   

18.
An acute to chronic idiopathic necrotizing meningoencephalitis was diagnosed in 5 Chihuahua dogs aged between 1.5 and 10 years. Presenting neurologic signs included seizures, blindness, mentation changes, and postural deficits occurring from 5 days to 5.5 months prior to presentation. Cerebrospinal fluid analyses from 2 of 3 dogs sampled were consistent with an inflammatory disease. Magnetic resonance imaging of the brain of 2 dogs demonstrated multifocal loss or collapse of cortical gray/white matter demarcation hypointense on T1-weighted images, with T2-weighted hyperintensity and slight postcontrast enhancement. Multifocal asymmetrical areas of necrosis or collapse in both gray and white matter of the cerebral hemispheres was seen grossly in 4 brains. Microscopically in all dogs, there was a severe, asymmetrical, intensely cellular, nonsuppurative meningoencephalitis usually with cystic necrosis in subcortical white matter. There were no lesions in the mesencephalon or metencephalon except in 1 dog. Immunophenotyping defined populations of CD3, CD11d, CD18, CD20, CD45, CD45 RA, and CD79a immunoreactive inflammatory cells varying in density and location but common to acute and chronic lesions. In fresh frozen lesions, both CD1b,c and CD11c immunoreactive dendritic antigen-presenting cells were also identified. Immunoreactivity for canine distemper viral (CDV) antigen was negative in all dogs. The clinical signs, distribution pattern, and histologic type of lesions bear close similarities to necrotizing meningoencephalitis as described in series of both Pug and Maltese breed dogs and less commonly in other breeds.  相似文献   

19.
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20.
Clinical and pathological studies of a neurological disorder of 3 adult Rottweiler dogs are described. Dogs developed proprioceptive losses involving the limbs, leading to progressively worsening ataxia and hypermetria. Blood and CSF fluid analyses were normal and radiographs and myelograms showed no compressive lesions of the spinal cord. At necropsy, severe demyelination of the dorsal and lateral funiculi of the cervical spinal cord was visible grossly. Microscopically there was more extensive, symmetrical involvement of the spinal cord and brain than was apparent grossly, with demyelination of white matter tracts and sparing of axons in affected areas. These changes were considered diagnostic for leucoencephalomyelopathy. This condition has not been previously reported in Australia, and is probably transmitted genetically, presumably as an autosomal recessive trait.  相似文献   

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