Multisystemic Chromatolytic Neuronal Degeneration in Cairn Terriers: A Case With Generalized Cataplectic Episodes

Multisystemic chromatolytic neuronal degeneration, a newly recognized disease of Cairn Terriers, is described in a second affected North American puppy. In this puppy, the early onset of hind limb weakness at 11 weeks and rapid development of signs of diffuse CNS involvement were distinctive. Signs of cerebellar dysfunction were prominent, but bouts of cataplectic collapse in this puppy constituted the most distinguishing clinical feature. Although electroencephalograph (EEG) recordings lacked a true rapid eye movement (REM) pattern during cataplectic episodes, cervical electromyograph (EMG) potentials ceased or diminished, and imipramine injection was associated with arousal. Postmortem studies revealed that chromatolytic degeneration was very widespread, affecting many neuronal populations in the brain and spinal cord as well as neurons in sensory ganglia. Although the pattern of chromatolysis varied among affected perikarya, chromatolysis was consistently related to dispersion and loss of ribosomes. In this puppy, as opposed to six studied previously, thoracolumbar myelomalacia also occurred symmetrically in the dorsal horns and adjoining funicular white matter. The metabolic derangement underlying this chromatolytic neuronal degeneration and myelomalacia remains unknown.     

Holter monitoring in clinically healthy Cavalier King Charles Spaniels, Wire-haired Dachshunds, and Cairn Terriers

Background: Few reported studies describe normal values from 24‐hour ECG (Holter) recordings of small breed dogs. Objectives: To investigate influence of breed, age, sex, body weight, degree of recording artifact, and mitral valve prolapse (MVP) on Holter recordings of 3 breeds of small dogs that have differing predispositions for myxomatous mitral valve disease. The study also assessed if heart rate (HR) at clinical examination (HRex) was associated with HR during Holter monitoring and evaluated the reproducibility of Holter variables. Animals: Fifty clinically healthy, privately owned dogs of the breeds Cavalier King Charles Spaniel (CKCS), Wire‐haired Dachshund (wD), or Cairn Terrier (CT). Methods: Prospective, longitudinal observational study. Dogs were recruited for clinical examination, echocardiography, and Holter monitoring. In 8 CKCS, Holter recordings were performed twice with a 7‐day interval. Arrhythmia and heart rate variability (HRV) analysis (time and frequency domain analysis) were performed on Holter recordings. Results: Fifteen out of 27 Holter derived variables were significantly associated with breed (P < .03), but not with age (P > .7), sex (P > .2), body weight (P > .7), degree of recording artifact (P > .4), or MVP (P > .6). During Holter recording, minimum (P= .0001) and mean HR (P= .0001) were higher in CKCS compared with wD. CKCS had significantly lower values than wD, CT, or both in 10 out of 13 HRV variables (P < .03). Minimum and mean HR during Holter recording were correlated with HRex (r= 0.55, P= .0003). HR and time domain variables had a coefficient of variation <10%. Conclusions and Clinical Importance: There is an influence of breed on Holter‐derived variables in 3 breeds of small dogs. Arrhythmia and HRV analysis can be performed on 24‐hour ambulatory ECG (Holter) recordings. Arrhythmia analysis includes HR measurements and identification of arrhythmias.     

Effect of dietary vitamin E and selenium supplementation on semen quality in Cairn Terriers with normospermia

Among others, selenium (Se) and vitamin E (VitE) have been provided to dogs to improve semen quality. However, scientific evidence documenting an effect in dogs is lacking. The aim of this study was to investigate the effect of supplementation of these antioxidants on various ejaculate parameters in a randomized, double‐blinded trial using Cairn Terrier males exhibiting normal seminal quality parameters. Three dogs each were fed a standardized diet and supplemented with 0.1 mg Se, 100 mg VitE or 0.1 mg Se + 100 mg VitE/dog for 3 months. Ejaculate analyses (volume, progressive motility, vitality, morphology, concentration) were performed before inclusion (D0) and after 1, 2 and 3 months (+1, +2, +3). At the same time, glutathione peroxidase (GSH‐PX) and VitE in seminal plasma (SP) and GSH‐PX in blood samples were determined. Vitamin E levels in SP were below the detection limit (1.0 mg/L) in all samples. GSH‐PX in blood (164.0–2794.4 IU/L) and SP (18.4–4326.0 IU/L) was highly variable. Supplementation only significantly affected the total percentage of sperm head abnormalities (p = .011). Time significantly affected the percentage of morphologically abnormal sperm (p = .025), sperm head abnormalities (p = .007), proximal droplets (p = .001) and GSH‐PX in SP (p = .015). Additionally, a significant interaction between time and group was identified for the percentage of membrane‐intact sperm (p = .048), head abnormalities (p = .018), acrosomal defects (p = .043) and proximal droplets (p = .002). Although some effects could be identified for selected parameters, we failed to identify a clear trend about how a 3 months VitE and/or Se supplementation affects semen parameters in normospermic Cairn Terriers.     

Clinical and Electrophysiological Characterization of Myokymia and Neuromyotonia in Jack Russell Terriers

Background: Generalized myokymia and neuromyotonia (M/NM) in Jack Russell Terriers (JRTs) is related to peripheral nerve hyperexcitability syndrome in humans, a symptom complex resulting from diverse etiologies. Objective: Clinical and electrodiagnostic evaluation is used to narrow the list of possible etiological diagnoses in JRTs with M/NM. Animals: Nine healthy JRTs and 8 affected JRTs. Methods: A prospective study was conducted comparing clinical and electrophysiological characteristics in 8 JRTs affected by M/NM with 9 healthy JRT controls. Results: All affected dogs except 1 had clinical signs typical of hereditary ataxia (HA). In 6 dogs, neuromyotonic discharges were recorded during electromyogram. Motor nerve conduction studies showed an axonal neuropathy in only 1 affected dog. Compared with controls, brainstem auditory‐evoked potentials (BAEP) showed prolonged latencies (P < .05) accompanied by the disappearance of wave components in 3 dogs. Onset latencies of tibial sensory‐evoked potentials (SEP) recorded at the lumbar intervertebral level were delayed in the affected group (P < .001). The BAEP and SEP results of the only neuromyotonic dog without ataxia were normal. Conclusions and Clinical Importance: The BAEP and spinal SEP abnormalities observed in JRTs with M/NM were associated with the presence of HA. Therefore, these electrophysiological findings presumably arise from the neurodegenerative changes characterizing HA and do not directly elucidate the pathogenesis of M/NM. An underlying neuronal ion channel dysfunction is thought to be the cause of M/NM in JRTs.     

Multisystemic chromatolytic neuronal degeneration in a Cairn terrier pup

In a four-month-old female Cairn terrier with mild episodic paraparesis, a multisystemic chromatolytic degeneration affected widespread neuronal populations in the brain and spinal cord as well as spinal, autonomic, and enteric ganglia. There was little axon degeneration or cell body loss, and the latter findings may explain the mild clinical signs. Among affected perikarya the extent and distribution of chromatolysis varied. While peripheral lysis of Nissl substance occurred often in spinal motoneurons, central chromatolysis was frequent in brain stem nuclei, and patchy Nissl loss appeared in some neurons including those in the cerebral cortex and spinal dorsal horns. Although prior studies of various chromatolytic neurodegenerations often have demonstrated characteristic massings of neurofilaments, the major, and invariable ultrastructural finding in this study was dispersion and loss of ribosomes. Neurofilamentous accumulations were observed less consistently. The clinical and pathologic findings in this pup were compared and constrasted with those made in prior studies of chromatolytic neurodegenerations.     

A Tremor Syndrome With a Central Axonopathy in Scottish Terriers

A central axonopathy in 2 male and 1 female Scottish Terrier puppies from 3 different but related litters is reported. Clinical signs consisting of severe whole-body tremors and ataxia were first detected at the age of 10 to 12 weeks. They worsened with activity and excitement and diminished during rest or sleep. Two dogs also had paraparesis. In 1 dog the neurological deficits progressed over several months. Neuropathological examination revealed widespread axonal changes, vacuolation, and gliosis in the white matter of the central nervous system.     

Shoulder Dysplasia in a Labrador

Abstract— —A condition of dysplasia of the right shoulder is described in a 10-month-old Labrador bitch, involving an ununited scapula tuberosity. The left shoulder showed marked "looseness" (joint laxity) similar to that of congenital subluxation of the shoulder, whilst third degree hip dysplasia was present bilaterally. Shoulder dysplasia is compared with elbow dysplasia and hip dysplasia. A link between the looseness of the left shoulder joint and the maldevelopment of the right shoulder is considered.
Résumé— —L'auteur décrit une dysplasie de l'épaule droite, constatée chez une chienne Labrador âgée de 10 mois, la tubérosité de l'omoplate ne donnant pas attache. L'épaule gauche préente une laxitt marquée, comparable à celle qu'entraîne la subluxation congénitale de l'épaule, et les hanches exhibent une dysplasie bilatérale du 3me degré. L'auteur compare la dysplasie de l'épaule, du coude et de la hanche. Il examine le rapport entre la laxité de l'articulation de l'épaule gauche et la malformation de l'épaule droite.
Zusammenfassung— —Ein Fall von Dysplasie der rechten Schulter bei einer 10 Monate alten Labradorhündin wird beschrieben. Die Tuberosität hatte sich nicht mit dem Schulterblatt vereinigt. Die linke Schulter zeigte eine beachtliche "Lockering" (loses Gelenk), ähnlich wie bei angeborener Subluxation der Schulter, und es bestand eine beidseitige Hüftdysplasie dritten Grades. Ein Vergleich zwischen Dysplasien der Schulter, des Ellbogens und der Hüfte wird aufgestellt und die Möglichkeit erwogen, daß die Lockerung des linken Schultergelenks mit der Unterentwicklung der rechten Schulter verbunden ist.     

Genetic analysis of presumed inherited eye diseases in Tibetan Terriers

We analysed the systematic environmental influences and the additive genetic variation for the presumed inherited eye diseases (PIED), membrana pupillaris persistens, distichiasis, primary lens luxation, non-congenital cataract, and progressive retinal atrophy, in Tibetan Terriers. Data were obtained from the International Kennel Club for Tibetan dog breeds in Germany. PIED were recorded in the years 1987 to 2001 by standardised protocols of the Dortmunder Kreis, the association for diagnosis of inherited eye diseases in animals (DOK). The material included 849 Tibetan Terriers from 596 litters in 203 different kennels. The multivariate linear animal model using residual maximum likelihood methods regarded the fixed effects of sex, birth year, experience of the veterinary ophthalmologist, litter size, percentage of examined dogs per litter, inbreeding coefficient, and age at examination. The common environment of the litter and the additive genetic effect of the animal were taken into account as randomly distributed effects. The heritability estimates for PIED in Tibetan Terriers were h2=0.17+/-0.04 (membrana pupillaris persistens), h2=0.04+/-0.03 (distichiasis), h2=0.13+/-0.04 (primary lens luxation), h2=0.13+/-0.04 (non-congenital cataract), and h2=0.49+/-0.08 (progressive retinal atrophy). The additive genetic correlation between non-congenital cataract and progressive retinal atrophy was highly positive rg=0.76+/-0.11, while that between membrana pupillaris persistens and progressive retinal atrophy rg=-0.43+/-0.14 was highly negative. The number of examinations performed by the veterinary ophthalmologists was associated with higher heritabilities for non-congenital cataract and progressive retinal atrophy. We concluded from our analysis that all investigated PIED in Tibetan Terriers are genetically influenced.     

Morphological investigations of the occipital area in adult American Staffordshire Terriers

Morphological investigations into the occipital area were carried out on the skulls of 24 adult American Staffordshire Terriers. The dorsal notch was found in one skull. The normal height (h) and width (W) of the foramen magnum was measured, and the foramen magnum index was calculated. In the case of the presence of the dorsal notch, total height (H) and normal height (h) of foramen magnum were measured, and dorsal notch height (N) was estimated. The mean value of the foramen magnum index (FMIa = W/H × 100) was 82.7. The foramen magnum index with the exception of the skull with dorsal notch (FMIb = W/h × 100) was 77.89. The dysplasia index (ISD = N/h × 100) was 44.05. A radiographic evaluation was made according to the method introduced by Rusbridge. Occipital dysplasia is not a clinical problem itself but can provoke one.     

Inheritance of cataracts and primary lens luxation in Jack Russell Terriers

OBJECTIVE: To characterize heritability and mode of inheritance of cataracts and primary lens luxation in Jack Russell Terriers. ANIMALS: 872 Jack Russell Terriers from which buccal epithelial cells were collected and phenotypes for cataracts and lens luxation were determined and an additional 1,898 Jack Russell Terriers without phenotypic information used to complete pedigree relationships and that were included in the analyses. PROCEDURES: Narrow-sense heritabilities and genetic correlation for cataracts and lens luxation were modeled by use of threshold analysis, whereas complex segregation analysis was used to characterize mode of inheritance. For the analyses, dogs < 6 years old, unless confirmed as having cataracts or lens luxation, were classified as an unknown phenotype. The possible involvement of an HSF4 mutation in cataracts was determined by DNA sequencing. RESULTS: Cataracts and primary lens luxation were highly heritable and genetically correlated, and neither was controlled by a single gene. Cataracts were not associated with an HSF4 mutation. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the data indicated that concerted selection against both cataracts and primary lens luxation when choosing breeding animals can be used to improve ocular health in Jack Russell Terriers.     

Evaluation of haplotypes associated with copper toxicosis in Bedlington Terriers in Australia

OBJECTIVE: To evaluate the haplotype distribution associated with the copper toxicosis gene and the segregation of the mutated allele in a Bedlington Terrier population in Australia. ANIMALS: 131 Bedlington Terriers. PROCEDURE: Samples of DNA and RNA were obtained from each dog. Genetic status of each dog was evaluated by use of the DNA markers C04107; single nucleotide polymorphism (SNP), which was adjacent to exon 2 of Murr1; and a deletion marker for exon 2. A subgroup of the study population was evaluated by use of biochemical and histologic techniques to elucidate the correlation between genotype and phenotype. RESULTS: We identified a recombination between the C04107 marker and Murr1 and a variation in a nucleotide in the splice site of exon 2 in our Bedlington Terrier cohort. Furthermore, we identified a novel haplotype associated with copper toxicosis in this cohort. CONCLUSIONS AND CLINICAL RELEVANCE: Our findings indicate that the deletion of exon 2 was not the sole cause of copper toxicosis, although only exon 2 deletion of Murr1 has been responsible for copper toxicosis in Bedlington Terriers. Although we failed to find a novel mutation in our cohort, we identified an affected dog family with an intact exon 2. Furthermore, we found that an SNP in the 5' splicing site of exon 2 may or may not be associated with a novel mutation of the Murr1 gene or other genes. Loss of linkage between the C04107 marker and the Murr1 gene was also identified in a certain family of dogs.     

Incessant Atrial Tachycardias in a Dog With Tricuspid Dysplasia

In a dog, tricuspid regurgitation due to congenital tricuspid dysplasia resulted in extreme right heart enlargement and right heart failure. Incessant supraventricular tachycardias were present, requiring the intravenous administration of verapamil to reduce the ventricular rate. Oral therapy using a combination of verapamil and quinidine was partially effective in controlling the ventricular rate during the following week. At that time, electrophysiologic studies were performed. They revealed that a succession of several atrial tachycardias with different cycle lengths, including one episode of atrial flutter, was present. Atrial activity was spanning the majority of the cycle length in all these arrhythmias. Epicardial mapping was performed during the atrial flutter. This enabled the detection of a depolarization wave-front traveling counterclockwise from the dorsolateral right atrium toward the right appendage, following the tricuspid valve annulus. No areas of abnormal conduction were detected. Because programmed electric stimulation maneuvers could not be performed, definitive conclusions about the mechanism of the arrhythmia could not be drawn. The two most likely possibilities were circus movement using part of the dilated tricuspid valve annulus as an anatomic barrier or a leading circle type of re-entry.     

Serum alkaline phosphatase activity in Scottish Terriers versus dogs of other breeds

OBJECTIVE: To determine whether Scottish Terriers have higher serum alkaline phosphatase (ALP) activities and a higher prevalence of diseases commonly associated with high serum ALP activity than do dogs of other breeds. DESIGN: Retrospective case-control study. ANIMALS: 85 Scottish Terriers and 340 age-matched control dogs that were not Scottish Terriers. PROCEDURE: Medical records were reviewed, and data for year of evaluation, age, sex, breed, serum ALP activity, and final diagnosis were recorded. RESULTS: Scottish Terriers had a significantly higher mean serum ALP activity than did control dogs (1,520 U/L vs 306 U/L). Regardless of breed, dogs that had a disease commonly associated with high serum ALP activity had a significantly higher mean serum ALP activity than did dogs without such diseases (1,304 U/L vs 427 U/L). Scottish Terriers were 2.4 times as likely to have a disease commonly associated with high serum ALP activity than were control dogs, but Scottish Terriers with diseases commonly associated with high serum ALP activity had a significantly higher mean ALP activity than did control dogs with such diseases (2,073 U/L vs 909 U/L), and Scottish Terriers without such diseases had a significantly higher mean serum ALP activity than did control dogs without such diseases (1,349 U/L vs 228 U/L). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that Scottish Terriers have higher serum ALP activities than do dogs of other breeds. Although Scottish Terriers also have a higher prevalence of diseases associated with high serum ALP activity, this alone did not explain the higher mean serum ALP activity in the breed.     

Lethal Acrodermatitis in Bull Terriers: A Problem of Defective Zinc Metabolism

Abstract— Three bull terrier pups from a litter of six developed exfoliative, crusty areas of alopecia, particularly affecting the feet and head, by the time they were seven weeks of age. Biopsies from two of the affected pups revealed parakeratotic hyperkeratosis consistent with zinc deficiency, but the dogs did not respond to oral zinc supplements. The breed, history and dermatopathology were considered consistent with lethal acrodermatitis of bull terriers, a condition that appears to be familial and autosomally recessive. Whereas similar acrodermatitic conditions in humans (acrodermatitis enteropathica) and cattle (lethal trait A46 of Black Pied Danish cattle) respond to oral zinc supplements, this condition in bull terriers may be due to an error in zinc metabolism at the cellular level. Attempts to treat one of the pups parenterally with zinc resulted in death after the fourth injection. Résumé— 3 choits d'une portée de 6 Bull Terriers ont développéà l'âge de 7 semaines une dermite podale et faciale exfoliative, crouteuse et alopécique. Les biopsies cutanées pratiquées sur 2 chiots ont révélé une hyperkératose parakératosique compatible avec une carence en zinc, mais les animaux n'ont pas répondu à une supplémentation en zinc. La race, l'anamnèse et l'aspect histologique, sont compatibles avec une acrondermatite léthale du Bull Terrier, maladie familiale, transmise sur un mode autosomal récessif. Des acrodermatites similaires chez l'homme (acrodermatitis enteropatica) et les bovins (anomalie léthale A46 de la Pie Noire Danoise) répondant à une supplémentation en zinc, cette affection chez le Bull Terrier pourrait êtro à une erreur dans le métabolisme du zinc au niveau cellulaire. Un essai de traitement d'un des chiots par vole parcutérale avec du zinc a abouti à sa mort après la quatrième injection. Zusammenfassung— Drei von sechs Bullterrierwelpen aus einem Wurf entwickelten im Alter von 7 Wochen exfoliative, krustige und haarlose Bezirke, besonders an Pfoten und Kopf. Biopsien von zwei der betroffenen Welpen zeigten eine Parakeratose, die bei Zinkmangel auftritt. Die Tiere sprachen jedoch nicht auf orale Zinksubstitution an. Rasse, Anamnese und Befunde der Hautuntersuchung stimmen mit der letalen Akrodermatitis der Bullterrier überein, einem familiären, autosomal rezessiv erblichen Leiden. Während ähnliche akrodermatitische Erkrankungen beim Menschen (Akrodermatitis enteropathica) und beim Rind (Letalfaktor A46 beim schwarzgefleckten Dänischen Rind) auf orale Zinkgaben ansprechen, ist diese Krankheit beim Bullterrier wahrscheinlich auf eine Störung im Zinkmetabolismus auf zellulärer Ebene zurückzuführen. Der Versuch, einen der Welpen parenteral mit Zink zu behandeln, führte zum Tod des Tieres nach der vierten Injektion. Resumen Tres cachorros de Bull Terrier de una camada de seis desarrollaron areas de alopecia exfoliativa, particularmente afectando a los pies y la cabeza, para el momento en que tenian siete semanas de edad. Biopsias de dos de los cachorros afectados revelaron hiperqueratosis paraqueratótica con deficiencia de zinc, pero los perros no respondían a los suplementos de zinc oral. La raza, historia y dermatopatología se consideraron consistentes en acrodermatitis letal de Bull Terriers, una condición que parece ser familial y autosómica recesiva. Mientras que condiciones de acrodermatitis similares en humanos (acrodermatitis enteropética) y ganado (rasgo letal A46 del ganado Black Pied Danish) respondían a los suplementos de zinc oral, esta condición en los Bull Terriers puede ser debida a un error en el metabolismo del zinc a nivel celular. Intentos de trater uno de los cachorros, por vía parenteral con zinc resultaron con la muerte después de la cuarta inyección.