RESUMO
Two 1-day-old full-term female calves from different farms located in the Brazilian state of Rio Grande do Sul were unable to stand due to paresis of the pelvic limbs. Both calves had spina bifida on the spinal lumbar segment and were submitted to euthanasia due to poor prognosis. Postmortem examination revealed cerebellar herniation, caudal displacement of the brainstem, rostral deviation of the cranial nerves, caudal extension of occipital lobes, absence of dorsal lamina of lumbar vertebrae with exposed spinal cord, myelodysplasia, kyphosis, segmental spinal agenesis, renal fusion, muscular atrophy, and arthrogryposis. Histology highlighted myelodysplasia (syringomyelia and diplomyelia) and muscular atrophy. The reverse transcription-polymerase chain reactions for ruminant pestivirus were negative. Based on these lesions, the diagnosis of complex neural tube and skeletal malformations was made. A review of previous publications on calves diagnosed with these malformations, originally called Chiari or Arnold-Chiari malformations, revealed a wide range of nervous system and skeletal lesions. These variations amplified the uncertainty regarding whether all cases represent the same disorder and reinforced the importance of reconfiguring the terminology.
Assuntos
Malformação de Arnold-Chiari , Doenças dos Bovinos , Animais , Bovinos , Feminino , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/patologia , Doenças dos Bovinos/congênito , Malformação de Arnold-Chiari/veterinária , Defeitos do Tubo Neural/veterinária , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/patologia , Animais Recém-Nascidos , BrasilRESUMO
Neural tube defects (NTDs) are severe congenital neurodevelopmental disorders arising from incomplete neural tube closure. Although folate supplementation has been shown to mitigate the incidence of NTDs, some cases, often attributable to genetic factors, remain unpreventable. The SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation; at present, however, the underlying mechanism remains unclear. Neural tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural plate. To determine the role of SHROOM3 in early developmental morphogenesis, we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate phase. Loss of SHROOM3 resulted in shorter neuroepithelial cells and smaller nuclei. These morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins, namely fibrous actin (F-actin), myosin II, and phospho-myosin light chain (PMLC), to the apical side of the neuroepithelial cells. Notably, these defects were not rescued by folate supplementation. RNA sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ morphogenesis. In summary, we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.
Assuntos
Proteínas do Citoesqueleto , Defeitos do Tubo Neural , Animais , Proteínas do Citoesqueleto/metabolismo , Tubo Neural/metabolismo , Macaca fascicularis , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/metabolismo , Defeitos do Tubo Neural/veterinária , Células Neuroepiteliais/metabolismo , Ácido Fólico/metabolismo , Organoides , CitoesqueletoRESUMO
We report a 9-year-old Thoroughbred gelding that had sudden onset lameness of the right forelimb with episodes of lateral decubitus and generalized pain after completion of a normal training session. The clinical signs subsequently became less pronounced with only mild right forelimb lameness. However, after further orthopaedic examination, it developed severe, acute ataxia and paraplegia, the Schiff-Sherrington phenomenon and risus sardonicus. At necropsy, a partial duplication of the cervical spinal cord was identified, consistent with split spinal cord malformation type II or diplomyelia. However, the clinical significance of this finding is not clear.
Assuntos
Doenças dos Cavalos , Defeitos do Tubo Neural , Medula Espinal/patologia , Animais , Cavalos , Masculino , Defeitos do Tubo Neural/veterináriaRESUMO
A rare dysraphic caudal spinal anomaly, or caudal agenesis, comprising a tethered spinal cord, was found in a tailless Holstein calf that presented ataxia and paresis with analgesia of the hind limbs. The gently and slimly tapered conus medullaris was poorly formed between S2 and S3 which indicated that it was lying more caudally. The caudal end of the filum terminale adhered to the inner periosteum of the vertebral arch at S4, which is compatible with tethering of the spinal cord. The dysraphic changes from the secondary neurulation error and the longitudinal deranged cord morphology that may have been caused by the caudad traction due to tethering were confirmed. This represents the first bovine case with definitive morphological confirmation.
Assuntos
Doenças dos Bovinos , Cauda Equina , Defeitos do Tubo Neural , Disrafismo Espinal , Animais , Bovinos , Imageamento por Ressonância Magnética , Defeitos do Tubo Neural/veterinária , Medula Espinal , Disrafismo Espinal/veterinária , Coluna VertebralRESUMO
BACKGROUND: Here, we report on the occurrence of neural tube defects (NTDs) in four related Shetland sheepdog puppies. NTDs present as a range of congenital malformations affecting the spine, skull and associated structures. Despite the severity of these malformations and their relatively high prevalence in humans, the aetiology is not well understood. It is even less well characterised in veterinary medicine. CASE REPORT: Affected puppies were investigated using computed tomography (CT) and then necropsy. CT identified a range of brain and spine abnormalities in the affected animals, including caudal anencephaly, encephalocele, spina bifida and malformed vertebrae. Other observed abnormalities in these puppies, including cranioschisis, atresia ani and hydrocephalus, may be secondary to, or associated with, the primary NTDs identified. CONCLUSION: This case report describes multiple related cases of NTDs in an Australian cohort of dogs. This study also highlights the potential of advanced imaging techniques in identifying congenital anomalies in stillborn and neonatal puppies. Further research is required to investigate the aetiology of NTDs in this group of affected Shetland sheepdogs.
Assuntos
Anencefalia/veterinária , Doenças do Cão , Defeitos do Tubo Neural/veterinária , Disrafismo Espinal/veterinária , Animais , Austrália , Cães , Feminino , Humanos , Gravidez , Tomografia Computadorizada por Raios XRESUMO
A 15-d-old female crossbreed calf was referred because of paraplegia since birth. Clinical examination revealed a skin defect covered by hair on the dorsal midline in the thoracic area of the spine. Thoracolumbar spinal cord neuroanatomic localization was determined based on neurologic examination. Computed tomography of the thoracolumbar spine revealed incomplete fusion of the vertebral arches from T6 to T10 and duplication of the vertebral arch of T7. At the level of T6-T7, duplication of the spinal cord with 2 segments completely separated by a septum of hyperattenuating, probably cartilaginous, tissue was noted. Histologically, the spinal segments had different degrees of duplication. Three central canals were detected in one region. Genetic investigation for the presence of methylenetetrahydrofolate reductase (MTHFR) polymorphism, which has been investigated in both human and veterinary medicine as a possible cause of neural tube defects and abortion, was carried out and was negative in both the calf and her dam.
Assuntos
Doenças dos Bovinos/congênito , Defeitos do Tubo Neural/veterinária , Animais , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/patologia , Feminino , Predisposição Genética para Doença , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/patologia , GravidezRESUMO
BACKGROUND: There is an association between Chiari malformations, syringomyelia (CMSM) and tethered cord syndrome (TCS) in people, suggesting Cavalier King Charles Spaniels (CKCS) with CMSM could also have TCS. Currently there are no data on the position of the caudal spinal cord structures in CKCS. OBJECTIVE: To describe and compare location of spinal cord termination in CKCS with weight-matched controls and to examine the relationship between SM and spinal cord termination. ANIMALS: Thirty-nine CKCS and 33 controls with thoracolumbar MRIs; 34 of 39 CKCS also had cervical MRIs. METHODS: Blinded retrospective study. Spinal cord and dural sac termination were determined from T2-weighted sagittal and transverse images and half-Fourier acquisition single-shot turbo spin echo sequences. Intra-observer reliability was determined using kappa analysis. Presence of SM was compared with location of spinal cord and dural sac termination. RESULTS: Intra-observer reliability was moderate for identifying spinal cord termination (Kappa = 0.6) and good for dural sac termination (Kappa = 0.8). The spinal cord terminated at lumbar vertebra 6 (L6) in 1, 7 (L7) in 22, and sacrum in 16 CKCS versus 9 at L6, 23 at L7, 1 at sacrum in controls. Spinal cord (P < .001) and dural sac (P = .002) termination were significantly more caudal in CKCS compared to controls. The presence of thoracolumbar SM was associated with more caudal dural sac termination in CKCS (P = .03). CONCLUSIONS AND CLINICAL IMPORTANCE: The relationship between TL SM and possible spinal cord tethering because of a more caudal dural sac termination should be investigated.
Assuntos
Doenças do Cão/diagnóstico por imagem , Medula Espinal/anormalidades , Siringomielia/veterinária , Animais , Cães , Dura-Máter/anormalidades , Feminino , Imageamento por Ressonância Magnética/veterinária , Masculino , Defeitos do Tubo Neural/diagnóstico por imagem , Defeitos do Tubo Neural/veterinária , Reprodutibilidade dos Testes , Estudos Retrospectivos , Siringomielia/diagnóstico por imagemRESUMO
A 4-mo-old French bulldog was presented with acute onset pain and reluctance to move. A tubular structure arising in the dorsal thoracic midline and extending from a cutaneous orifice into deeper tissues was palpated on physical examination. Computed tomography with sinography revealed a dermoid sinus associated with spina bifida at the level of T3-T4. On surgical exploration, the dermoid sinus was found to communicate with the dura. Histology confirmed the diagnosis and classification as a type VI dermoid sinus. The pain response and hyperesthesia were suspected to be the result of tethered cord syndrome. Complete resolution of clinical signs was appreciated post-surgery, with the patient still free of clinical signs 3 mo later.
Assuntos
Doenças do Cão/diagnóstico , Defeitos do Tubo Neural/veterinária , Espinha Bífida Oculta/veterinária , Animais , Doenças do Cão/congênito , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Hiperestesia/etiologia , Hiperestesia/fisiopatologia , Hiperestesia/veterinária , Masculino , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/patologia , Defeitos do Tubo Neural/cirurgia , Dor/etiologia , Dor/fisiopatologia , Dor/veterinária , Espinha Bífida Oculta/diagnóstico , Espinha Bífida Oculta/patologia , Espinha Bífida Oculta/cirurgia , Tomografia Computadorizada por Raios X/veterináriaRESUMO
BACKGROUND: The teratogenic effects of immunomodulatory and certain antimicrobial therapies are described in small rodents and humans. While the described teratogenic effects in small rodents have been extrapolated to make conclusions about its use in the pregnant dam, teratogenic effects of prednisone and doxycycline have not yet been reported in the dog. Here we report and describe midline defects observed in a litter of golden retriever puppies exposed to mid-gestational immunosuppressive and antimicrobial therapy. CASE PRESENTATION: Twenty-one days into gestation, the dam of a litter of eight golden retriever puppies was administered prednisone, doxycycline, and tramadol as treatment for immune-mediated polyarthritis. The individuals in the litter were subsequently diagnosed with a variety of midline defects and congenital cardiac defects. This case series describes the variety of identified defects and presents a descriptive account of complex congenital abnormalities that are likely secondary to teratogenic effects of one or more drugs administered during gestation. The available puppies, dam, and grand dam underwent thorough physical examination, complete echocardiogram, and where indicated, advanced imaging with various surgical corrections when possible. Numerous midline congenital defects and congenital heart disease were identified in the puppies evaluated. Ultimately 5 of 8 puppies born to the dam were presented for thorough evaluation. The midline defects include: gastroschisis (1), peritoneopericardial diaphragmatic hernias (4, PPDH), umbilical hernia (4), unilateral cryptorchidism (1 of 4 males), cleft palate (1), renal agenesis (1), renal abnormalities (1), sternal and vertebral abnormalities (3), remnant liver lobe (1) and malformations consistent with ductal plate malformations with congenital hepatic fibrosis (1). The congenital cardiac defects include: ventricular septal defect (4, VSD) and subaortic stenosis (4, SAS). The presence of greater than one congenital defect was noted in all 5 of the dogs evaluated. Surgical correction was necessary for PPDH in 4 puppies. Medical intervention was recommended for congenital cardiac disease in 1 puppy. CONCLUSION: This case report is the first to describe midline defects in dogs that have been exposed to immunomodulatory therapy during gestation. A causative relationship between mid-gestational immunomodulatory exposure and midline defects cannot be proven, however, this case supports a clear association and provides case-based evidence to support its avoidance when possible.
Assuntos
Anormalidades Induzidas por Medicamentos/veterinária , Antibacterianos/toxicidade , Anti-Inflamatórios/toxicidade , Cães/anormalidades , Doxiciclina/toxicidade , Cardiopatias Congênitas/veterinária , Prednisona/toxicidade , Anormalidades Induzidas por Medicamentos/etiologia , Anormalidades Induzidas por Medicamentos/patologia , Animais , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Artrite/complicações , Artrite/tratamento farmacológico , Artrite/veterinária , Doxiciclina/uso terapêutico , Ecocardiografia/veterinária , Feminino , Cardiopatias Congênitas/induzido quimicamente , Masculino , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/veterinária , Prednisona/uso terapêutico , Gravidez , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/veterináriaAssuntos
Doenças do Cão/diagnóstico , Defeitos do Tubo Neural/veterinária , Doenças da Medula Espinal/veterinária , Animais , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Feminino , Seguimentos , Imageamento por Ressonância Magnética/veterinária , Masculino , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/patologia , Defeitos do Tubo Neural/cirurgia , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Medula Espinal/cirurgia , Doenças da Medula Espinal/diagnóstico , Doenças da Medula Espinal/patologia , Doenças da Medula Espinal/cirurgiaRESUMO
Neuroectodermal developmental anomalies are reported rarely in cetaceans and central nervous system cysts are not described. We describe the gross, microscopical, histochemical and immunohistochemical features of a neuraxial myelencephalic cyst in a stranded neonatal Burmeister's porpoise (Phocoena spinipinnis). Grossly, a subdural, extra-axial, well-demarcated, yellow fluid-filled cystic structure (1.9 × 1.6 × 1 cm) expanded the left foramen of Luschka, the left caudolateral cerebellar recess and the left cranioventral myelencephalon. The cyst displaced the ipsilateral ventral paraflocculus and distended the underlying cranial nerves IX, X, XI and XII. Microscopically, the cystic structure was lined by a monolayer of low cuboidal to flattened epithelium supported by a thin fibrovascular matrix. Immunohistochemistry (IHC) revealed strong and diffuse expression of AE1/AE3 and focal positivity for vimentin. IHC for epithelial membrane antigen, glial fibrillary acid protein, synaptophysin and S100 was negative. Based on these findings, an extra-axial cyst of the choroid plexus of the fourth ventricle (CCPFV) was diagnosed. The pathological relevance of the CCPFV in this case is uncertain. The cause of death involved severe perinatal interspecific (shark) trauma. The present case provides the first evidence of a neuroepithelial cyst in cetacean species.
Assuntos
Plexo Corióideo/anormalidades , Defeitos do Tubo Neural/veterinária , Phocoena/anormalidades , Animais , Animais Recém-NascidosRESUMO
CASE DESCRIPTION An 11-year-old English Cocker Spaniel was evaluated because of chronic progressive ataxia of the hind limbs. CLINICAL FINDINGS The dog had no history of previous illness, and findings of physical examination and laboratory tests were unremarkable. Neurologic examination revealed that the dog was ambulatory with severe ataxia of the hind limbs. Proprioception was decreased in the right and left hind limbs (right affected more than left), and spinal reflexes were bilaterally unremarkable. Moderate signs of pain were detected during palpation of the lumbar portion of the vertebral column. Findings suggested a lesion within the thoracolumbar or lumbar segments of the spinal cord. Magnetic resonance imaging revealed extradural spinal cord compression attributable to an extradural space-occupying lesion originating from or infiltrating the L4 lamina on the right side. TREATMENT AND OUTCOME Hemilaminectomy was performed to remove the extradural lesion. Histologic findings for tissue samples collected during the procedure were consistent with a neurenteric cyst. The late onset and progression of clinical signs of this rare congenital malformation were suspected to have been the result of enlargement of the neurenteric cyst through continuous production of mucus by goblet cells. The dog responded favorably to surgical decompression and was clinically normal 1 year after surgery. It was euthanized 2 years after surgery for an unrelated reason (end-stage heart disease), and no neurologic deficits were evident before that point. CLINICAL RELEVANCE Congenital neurenteric cysts should be considered as a differential diagnosis for neoplastic disease in dogs in which results of diagnostic imaging indicate the presence of an extradural mass affecting vertebral structures.
Assuntos
Doenças do Cão/diagnóstico , Defeitos do Tubo Neural/veterinária , Compressão da Medula Espinal/veterinária , Animais , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Feminino , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/cirurgia , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/patologiaRESUMO
Neuroectodermal developmental anomalies are reported rarely in cetaceans and central nervous system cysts are not described. We describe the gross, microscopical, histochemical and immunohistochemical features of a neuraxial myelencephalic cyst in a stranded neonatal Burmeister's porpoise (Phocoena spinipinnis). Grossly, a subdural, extra-axial, well-demarcated, yellow fluid-filled cystic structure (1.9 × 1.6 × 1 cm) expanded the left foramen of Luschka, the left caudolateral cerebellar recess and the left cranioventral myelencephalon. The cyst displaced the ipsilateral ventral paraflocculus and distended the underlying cranial nerves IX, X, XI and XII. Microscopically, the cystic structure was lined by a monolayer of low cuboidal to flattened epithelium supported by a thin fibrovascular matrix. Immunohistochemistry (IHC) revealed strong and diffuse expression of AE1/AE3 and focal positivity for vimentin. IHC for epithelial membrane antigen, glial fibrillary acid protein, synaptophysin and S100 was negative. Based on these findings, an extra-axial cyst of the choroid plexus of the fourth ventricle (CCPFV) was diagnosed. The pathological relevance of the CCPFV in this case is uncertain. The cause of death involved severe perinatal interspecific (shark) trauma. The present case provides the first evidence of a neuroepithelial cyst in cetacean species.
anomalias de desenvolvimento neuroectodérmicas são raramente relatadas em cetáceos e cistos do sistema nervoso central não são descritos. Descrevemos as características macroscópicas, microscópicas, histoquímicas e imuno-histoquímicas de um cisto mielencefálico neuroaxial em uma toninha de Burmeister neonatal encalhada (Phocoena spinipinnis). Grosso modo, uma estrutura cística amarela subdural, extra-axial, bem demarcada e cheia de líquido (1,9 × 1,6 × 1 cm) expandiu o forame esquerdo de Luschka, o recesso cerebelar caudolateral esquerdo e o mielencéfalo cranioventral esquerdo. O cisto deslocou o paraflóculo ventral ipsilateral e distendeu os nervos cranianos subjacentes IX, X, XI e XII. Microscopicamente, a estrutura cística foi revestida por uma monocamada de epitélio cubóide a achatado baixo, suportada por uma fina matriz fibrovascular. A imuno-histoquímica (IHC) revelou forte e difusa expressão de AE1 / AE3 e positividade focal para vimentina. O IHC para antígeno da membrana epitelial, proteína do ácido fibrilar glial, sinafofisina e S100 foi negativo. Com base nesses achados, foi diagnosticado um cisto extra-axial do plexo coróide do quarto ventrículo (CCPFV). A relevância patológica do CCPFV neste caso é incerta. A causa da morte envolveu traumatismo interespecífico (tubarão) perinatal grave. O presente caso fornece a primeira evidência de um cisto neuroepitelial em espécies de cetáceos. patologia cetáceo Anomalia congenita neuroectoderma
Assuntos
Plexo Corióideo/anormalidades , Phocoena/anormalidades , Animais Recém-Nascidos , Defeitos do Tubo Neural/veterináriaRESUMO
Two horses euthanized for neurologic deficits were diagnosed with hamartomatous myelodysplasia of the spinal cord. One was a 5-week-old Holsteiner colt exhibiting spasms of muscle rigidity in the extensor muscles of the limbs and epaxial muscles, and the other was a 3-year-old Thoroughbred colt exhibiting progressive ataxia and hypermetria in the pelvic limbs. Each had focal disorganization of the white and gray matter of the spinal cord forming a mass interspersed with neurons, glial cells, and disoriented axon bundles. In the Holsteiner colt, the mass was at the level of C5 and included islands of meningeal tissue contiguous with the leptomeninges. The mass occluded the central canal forming hydromyelia cranial to the occlusion. In the Thoroughbred colt, the mass was at the level of L1 on the dorsal periphery of the spinal cord and did not involve the central canal.
Assuntos
Hamartoma/veterinária , Doenças dos Cavalos/diagnóstico , Defeitos do Tubo Neural/veterinária , Animais , Ataxia/patologia , Ataxia/veterinária , Hamartoma/diagnóstico , Hamartoma/patologia , Membro Posterior/patologia , Doenças dos Cavalos/patologia , Cavalos , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/patologia , Espasmo/patologia , Espasmo/veterinária , Medula Espinal/patologiaRESUMO
Spina bifida with or without meningocele or meningomyelocele is encountered infrequently in small animal practice. The English bulldog and Manx cat are breeds predisposed. Although often silent clinically, in those animals with clinical signs, it is important to recognize the signs early and to understand the appropriate imaging modalities employed in establishing a diagnosis. In a select population of affected animals, proposed surgical intervention may be considered to prevent neurologic decline, prevent secondary complications, and potentially improve outcomes.
Assuntos
Doenças do Gato/congênito , Doenças do Cão/congênito , Defeitos do Tubo Neural/veterinária , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/cirurgia , Gatos , Sistema Nervoso Central/diagnóstico por imagem , Sistema Nervoso Central/embriologia , Sistema Nervoso Central/fisiopatologia , Doenças do Cão/diagnóstico , Doenças do Cão/cirurgia , Cães , Imageamento por Ressonância Magnética/veterinária , Meningocele , Meningomielocele , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/etiologia , Defeitos do Tubo Neural/cirurgia , Disrafismo EspinalAssuntos
Cauda Equina/patologia , Doenças do Cão/congênito , Defeitos do Tubo Neural/veterinária , Doenças do Sistema Nervoso Periférico/veterinária , Animais , Doenças do Cão/patologia , Cães , Feminino , Defeitos do Tubo Neural/patologia , Defeitos do Tubo Neural/cirurgia , Doenças do Sistema Nervoso Periférico/patologiaRESUMO
A 9 yr old spayed female German shepherd dog was referred for MRI of the thoracic and lumbar spine because she had clinical signs of chronic neurogenic bladder dysfunction of an unknown cause. Transverse T2-weighted images identified a type II split cord malformation (i.e., diastematomyelia) in the thoracic spine. Split cord malformations are forms of spinal dysraphism where the abnormal development of spinal cord results in sagittal splitting of a portion of the cord into two hemicords. The location of the lesion in the thoracic spine was consistent with the dog's clinical signs of an upper motor neuron bladder. Split cord malformations that occur in humans have similar MRI characteristics and can result in similar clinical signs as those identified in the dog described in this report.
Assuntos
Doenças do Cão/diagnóstico , Imageamento por Ressonância Magnética/veterinária , Doenças do Sistema Nervoso/veterinária , Defeitos do Tubo Neural/veterinária , Medula Espinal/anormalidades , Animais , Cães , Evolução Fatal , Feminino , Doenças do Sistema Nervoso/diagnóstico , Defeitos do Tubo Neural/diagnóstico , Coluna Vertebral/anormalidadesRESUMO
The present study records recurrent outbreaks of myelodysplasia of unknown origin occurring in a specific geographical location in the north of Spain, and involving up to 30% of the calves born in affected herds. The affected calves were of different breeds and displayed non-progressive signs of spinal cord dysfunction. The disease has occurred annually in February-March over a period of at least 15 years. Only calves born to cattle grazed on mountainside pastures and under high grazing pressure were affected. Seven calves were subjected to necropsy examination. Myelodysplasia was not associated with vertebral defects or arthrogryposis and involved the entire length of the spinal cord. Microscopically, there was abnormal distribution of the grey matter, aberrations of the central canal and failure of formation of the ventral median fissure. Infectious, nutritional and physical disorders were ruled out as possible aetiologies. A critical period of embryonic susceptibility to the causal agent was identified. This was during the time of secondary neurulation when cows in the early stages of gestation were grazed on mountainside pastures. Consequently, the presence of neuroteratogenic plants in these pastures is proposed as a likely cause. Two plants, Carex brevicollis and Erythronium dens-canis, which contain alkaloids, were identified on the mountainsides where affected cattle were grazed and not in other pastures, and are proposed as the possible aetiology of the disease.
Assuntos
Doenças dos Bovinos/patologia , Surtos de Doenças/veterinária , Malformações do Sistema Nervoso/veterinária , Defeitos do Tubo Neural/veterinária , Medula Espinal/anormalidades , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/etiologia , Feminino , Idade Gestacional , Malformações do Sistema Nervoso/epidemiologia , Malformações do Sistema Nervoso/etiologia , Malformações do Sistema Nervoso/patologia , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/etiologia , Defeitos do Tubo Neural/patologia , Plantas Tóxicas/toxicidade , Recidiva , Estações do Ano , Medula Espinal/fisiopatologia , Fatores de TempoRESUMO
Nonhuman primates have been a common animal model to evaluate experimentally induced malformations. Reports on spontaneous malformations are important in determining the background incidence of congenital anomalies in specific species and in evaluating experimental results. Here we report on a stillborn cynomolgus monkey (Macaca fascicularis) with multiple congenital anomalies from the colony maintained at the Southwest National Primate Research Center at the Texas Biomedical Research Institute, San Antonio, Texas. Physical findings included low birth weight, craniorachischisis, facial abnormalities, omphalocele, malrotation of the gut with areas of atresia and intussusception, a Meckel diverticulum, arthrogryposis, patent ductus arteriosus, and patent foramen ovale. The macaque had normal male external genitalia, but undescended testes. Gestational age was unknown but was estimated from measurements of the limbs and other developmental criteria. Although cytogenetic analysis was not possible due to the tissues being in an advanced state of decomposition, array Comparative Genomic Hybridization analysis using human bacterial artificial chromosome clones was successful in effectively eliminating aneuploidy or any copy number changes greater than approximately 3-5 Mb as a cause of the malformations. Further evaluation of the animal included extensive imaging of the skeletal and neural tissue defects. The animal's congenital anomalies are discussed in relation to the current hypotheses attempting to explain the frequent association of neural tube defects with other abnormalities.
Assuntos
Hérnia Umbilical/veterinária , Macaca fascicularis/anormalidades , Macaca fascicularis/genética , Defeitos do Tubo Neural/veterinária , Animais , Hibridização Genômica Comparativa , Análise Citogenética , Hérnia Umbilical/genética , Hérnia Umbilical/patologia , Imageamento por Ressonância Magnética , Masculino , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/patologia , Natimorto/veterinária , Microtomografia por Raio-XRESUMO
A 7-month-old male neutered cat was referred for paraparesis and painful sensation at the level of T13 vertebra where a dermal cyst was observed. Spine radiographs and magnetic resonance imaging (MRI) showed a well-encapsulated cyst communicating with the meninges and spinal cord, suggestive of hydromyelia and myelodysplasia. Dorsal laminectomy was performed and the cyst was completely removed. The day after surgery, the cat was ambulatory paraparetic. Involuntary defecation was observed for only a few days. The surgical specimen was cystic and covered by skin. Microscopic examination revealed a hollow hemispheric mass of glial fibrillary acidic protein (GFAP)-positive neural tissue lined by ependyma and formed of glia and vascular structures consistent with myelomeningocele (MMC). Only anecdotal descriptions of MMC have been published in the veterinary literature, mainly in the lumbosacral spinal cord. To the authors' knowledge, this is the first report of a MMC with tethered spinal cord syndrome in a cat successfully treated surgically.