Presence of thoracic and lumbar vertebral malformations in pugs with and without chronic neurological deficits.

Congenital vertebral malformations (CVMs) are common in brachycephalic dogs such as the pug, and are often considered incidental findings. However, specific CVMs have been suggested to be associated with neurological deficits in pugs. The objective of this study was to investigate the clinical importance of CVMs in the pug by comparing computed tomography studies of the thoracolumbar spine from pugs without neurological deficits with those from pugs with a confirmed T3-L3 spinal cord lesion and neurological deficits consistent with a chronic T3-L3 myelopathy. A total of 57 pugs were recruited into the study from Sweden (n=33), United Kingdom (n=21) and Norway (n=3); 30 with neurological deficits and 27 without. Focal T3-L3 pathology was confirmed in all pugs with neurological deficits by magnetic resonance imaging (n=29) and/or pathology (n=15). Computed tomography studies of the thoracolumbar spine from pugs with and without neurological deficits were compared to investigate possible associations between presentation of neurological deficits consistent with chronic T3-L3 pathology and signalment variables, presence of CVMs and type of CVMs. Congenital vertebral malformations were as common in pugs with, as in pugs without, neurological deficits. Regardless of neurological status, the majority of pugs (96%) presented with one or more CVM. An association between presence, or type of CVM in the T1-L3 vertebral column, and neurological deficits consistent with T3-L3 pathology could not be confirmed.

Degenerative Encephalopathy in Nova Scotia Duck Tolling Retrievers Presenting with a Rapid Eye Movement Sleep Behavior Disorder.

BACKGROUND: Neurodegenerative diseases are a heterogeneous group of disorders characterized by loss of neurons and are commonly associated with a genetic mutation. HYPOTHESIS/OBJECTIVES: To characterize the clinical and histopathological features of a novel degenerative neurological disease affecting the brain of young adult Nova Scotia Duck Tolling Retrievers (NSDTRs). ANIMALS: Nine, young adult, related NSDTRs were evaluated for neurological dysfunction and rapid eye movement sleep behavior disorder. METHODS: Case series review. RESULTS: Clinical signs of neurological dysfunction began between 2 months and 5 years of age and were progressive in nature. They were characterized by episodes of marked movements during sleep, increased anxiety, noise phobia, and gait abnormalities. Magnetic resonance imaging documented symmetrical, progressively increasing, T2-weighted image intensity, predominantly within the caudate nuclei, consistent with necrosis secondary to gray matter degeneration. Abnormalities were not detected on clinicopathological analysis of blood and cerebrospinal fluid, infectious disease screening or urine metabolite screening in most cases. Postmortem examination of brain tissue identified symmetrical malacia of the caudate nuclei and axonal dystrophy within the brainstem and spinal cord. Genealogical analysis supports an autosomal recessive mode of inheritance. CONCLUSIONS AND CLINICAL IMPORTANCE: A degenerative encephalopathy was identified in young adult NSDTRs consistent with a hereditary disease. The prognosis is guarded due to the progressive nature of the disease, which is minimally responsive to empirical treatment.

Cervical spinal intradural arachnoid cysts in related, young pugs.

Seven related young pugs were diagnosed with cervical spinal intradural arachnoid cysts by magnetic resonance imaging (n = 6) and myelography (n = 1). All dogs were presented with skin abrasions on their thoracic limbs and non-painful neurological deficits, indicating a C1-T2 myelopathy. In all six dogs examined by magnetic resonance imaging not only the spinal arachnoid cyst but also a concomitant, most likely secondary, syringohydromyelia was confirmed. Pedigree analysis suggested a genetic predisposition for spinal arachnoid cysts in this family of pugs. Generalised proprioceptive deficits more pronounced in the thoracic limbs suggesting a focal cervical spinal cord lesion, with concomitant skin abrasions on the dorsal aspect of the thoracic limbs in a young pug, should alert veterinarians to the possibility of cervical spinal arachnoid cysts.

New aspects of hereditary ataxia in smooth-haired fox terriers.

Hereditary ataxia was diagnosed in three smooth-haired fox terrier puppies from Sweden, 25 years after the previous known case in the breed. In addition to the characteristic spinal cord pathology, brain involvement was evident clinically, in the form of behavioural changes and bilaterally decreased menace responses, and histopathologically, with degenerative changes in the brainstem. The striking similarities to hereditary ataxia in the Jack Russell terrier suggest the same disease process in both breeds. A common ancestor, a female dog born in 1951 and considered a carrier of the disease at that time, was found in both the maternal and paternal lines of the three puppies.