Retrospective evaluation of hyperproteinorrachia without pleocytosis (albuminocytologic dissociation) and survival in dogs.

Background: Hyperproteinorrachia (raised cerebrospinal fluid total protein [CSF-TP]) without pleocytosis (HP) (also known as albuminocytologic dissociation) is identified in dogs with different neurologic diseases. However, the association between survival and increased CSF-TP is unknown.

Objectives: (a) Identify conditions commonly associated with HP in dogs and (b) investigate whether higher CSF-TP concentrations or other relevant factors are associated with 1-year survival.

Species-specific consequences of an E40K missense mutation in superoxide dismutase 1 (SOD1).

A glutamic acid to lysine (E40K) residue substitution in superoxide dismutase 1 (SOD1) is associated with canine degenerative myelopathy: the only naturally occurring large animal model of amyotrophic lateral sclerosis (ALS). The E40 residue is highly conserved across mammals, except the horse, which naturally carries the (dog mutant) K40 residue. Here we hypothesized that in vitro expression of mutant dog SOD1 would recapitulate features of human ALS (ie, SOD1 protein aggregation, reduced cell viability, perturbations in mitochondrial morphology and membrane potential, reduced ATP production, and increased superoxide ion levels); further, we hypothesized that an equivalent equine SOD1 variant would share similar perturbations in vitro, thereby explain horses' susceptibility to certain neurodegenerative diseases.

Assessing pathological changes within the nucleus ambiguus of horses with recurrent laryngeal neuropathy: An extreme, length-dependent axonopathy.

Introduction: Equine recurrent laryngeal neuropathy (RLN) is a naturally occurring model of length-dependent axonopathy characterized by asymmetrical degeneration of recurrent laryngeal nerve axons (RLn). Distal RLn degeneration is marked, but it is unclear whether degeneration extends to include cell bodies (consistent with a neuronopathy).

Methods: With examiners blinded to RLN severity, brainstem location, and side, we examined correlations between RLN severity (assessed using left distal RLn myelinated axon count) and histopathological features (including chromatolysis and glial responses) in the nucleus ambiguus cell bodies, and myelinated axon count of the right distal RLn of 16 horses.

Pathological classification of equine recurrent laryngeal neuropathy.

Recurrent Laryngeal Neuropathy (RLN) is a highly prevalent and predominantly left-sided, degenerative disorder of the recurrent laryngeal nerves (RLn) of tall horses, that causes inspiratory stridor at exercise because of intrinsic laryngeal muscle paresis. The associated laryngeal dysfunction and exercise intolerance in athletic horses commonly leads to surgical intervention, retirement or euthanasia with associated financial and welfare implications. Despite speculation, there is a lack of consensus and conflicting evidence supporting the primary classification of RLN, as either a distal ("dying back") axonopathy or as a primary myelinopathy and as either a (bilateral) mononeuropathy or a polyneuropathy; this uncertainty hinders etiological and pathophysiological research.

Reference ranges and reliability of transabdominal ultrasonographic renal dimensions in thoroughbred horses.

The aims of this study were to establish a normal reference range (mean ± 2 SD) and assess reliability of renal dimensions obtained using transabdominal ultrasonography in Thoroughbred horses (n = 7). A minimum of three ultrasonographic cineloops were obtained from each intercostal space and the left paralumbar fossa by two observers daily for three consecutive days. Renal length, width, and thickness and cortex, medulla, and pelvic dimensions were obtained.