RESUMO
Most modern dog breeds were developed within the last two hundred years, following strong and recent human selection based predominantly on aesthetics, with few modern breeds constructed solely to maximize their work potential. In many cases, these working breeds represent the last remnants of now lost populations. The Patagonian sheepdog (PGOD), a rare herding breed, is a remarkable example of such a population. Maintained as an isolated population for over 130 years, the PGOD offers a unique opportunity to understand the genetic relationship amongst modern herding breeds, determine key genomic structure of the founder PGOD populations, and investigate how canine genomic data can mirror human migration patterns. We thus analyzed the population structure of 159 PGOD, comparing them with 1514 dogs representing 175 established breeds. Using 150,069 SNPs from a high-density SNP genotyping array, we establish the genomic composition, ancestry, and genetic diversity of the population, complementing genomic data with the PGOD's migratory history to South America. Our phylogenetic analysis reveals that PGODs are most closely related to modern herding breeds hailing from the United Kingdom. Admixture models illustrate a greater degree of diversity and genetic heterogeneity within the very small PGOD population than in Western European herding breeds, suggesting the PGOD predates the 200-year-old construction of most pure breeds known today. We thus propose that PGODs originated from the foundational herding dogs of the UK, prior to the Victorian explosion of breeds, and that they are the closest link to a now-extinct population of herding dogs from which modern herding breeds descended.
Assuntos
Genoma , Cães Trabalhadores , Animais , Cruzamento , Cães , Genômica , FilogeniaRESUMO
Background: Cerebellar cortical degeneration (CCD) is the premature death of cerebellar neurons of heterogeneous etiology that is uncommonly observed as a neurological complication of certain neoplasia. Case Description: Here, we report an 8-month-old male domestic cat with altered consciousness, symmetric ataxia, hypermetric gait, vertical positional nystagmus, mydriasis, strabismus, intention tremor of the head, and increased patellar reflexes. Neuroanatomical diagnosis suggested a multifocal brain dysfunction (cerebellar and cerebral). The cat tested seropositive for feline leukemia virus. Cerebrospinal fluid analysis indicated mononuclear and neutrophilic pleocytosis. Contrast computed tomography imaging revealed multiple hypodense heterogeneous areas in both cerebral hemispheres, mild ventriculomegaly at the level of the caudal fossa, and a circular sharply marginated, homogeneously hyperdense mass occupying the right cerebellar hemisphere. Postmortem study indicated a 1.1 × 1.3 × 1.2 cm mass in the right cerebellar hemisphere close to the vermis. Histopathological analysis showed diffuse and severe Purkinje cell loss with a decrease in granular cell density and moderate gliosis compatible with CCD. Further, numerous neoplastic lymphoid cells were observed in the infiltrated mass, consistent with a diagnosis of central nervous system (CNS) lymphoma. Immunohistochemistry showed CD20 expression, indicative of a B-cell immunophenotype. In humans, CCD is reported as a rare paraneoplastic syndrome in patients with Hodgkin lymphoma. CNS lymphoma and/or Feline Leukemia Virus (FeLV) infection were both considered as a possible cause of CCD in this case. Conclusion: This is the first described case of possible paraneoplastic cerebellar cortical degeneration associated with CNS lymphoma and/or FeLV infection in a domestic cat.
Assuntos
Doenças do Gato/virologia , Vírus da Leucemia Felina/fisiologia , Degeneração Paraneoplásica Cerebelar/veterinária , Infecções por Retroviridae/veterinária , Infecções Tumorais por Vírus/veterinária , Animais , Doenças do Gato/patologia , Gatos , Cerebelo/patologia , Masculino , Degeneração Paraneoplásica Cerebelar/patologia , Degeneração Paraneoplásica Cerebelar/virologia , Infecções por Retroviridae/patologia , Infecções por Retroviridae/virologia , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/virologiaRESUMO
Gurltia paralysans is a rare metastrongylid nematode of domestic cats that is found mainly in the veins of the spinal cord subarachnoid space and parenchyma. Endemic regions for G. paralysans mainly include Chile and Argentina. The ante mortem diagnosis of gurltiosis is difficult and based primarily on neurological signs, epidemiological factors, and the exclusion of other causes of feline myelopathies. The purpose of this retrospective case series was to describe clinical, imaging, and pathologic characteristics in nine domestic cats naturally infected with G. paralysans. Imaging tests included radiography, myelography, computed tomographic myelography (myelo-CT), and magnetic resonance imaging (MRI). Neurological signs included paraparesis, paraplegia, pelvic limb ataxia and proprioceptive deficits, pelvic limb tremors, lumbosacral hyperesthesia, and tail trembling or atony. Complete blood count findings included a decrease in the mean corpuscular hemoglobin concentration value in eight cats. Eosinophilia in peripheral blood was observed in three cats, and thrombocytopenia was observed in three cats. Cerebrospinal fluid analysis revealed mononuclear pleocytosis in five cases. Myelo-CT showed diffuse enlargement of the spinal cord at the midthoracic, lumbar, and sacral regions in all cats. Magnetic resonance image findings in the thoracic and lumbar region demonstrated multiple small nodular areas of T2 hyperintensity in the periphery of the spinal cord parenchyma. Localized intraparenchymal areas of increased T2 intensity were also observed in the thoracolumbar spinal cord and lumbosacral conus medullaris. In conclusion, G. paralysans should be considered as a differential diagnosis for domestic cats in endemic regions that have this combination of clinical and imaging characteristics.