Clinical Findings and Prevalence of the Mutation Associated with Primary Ciliary Dyskinesia in Old English Sheepdogs

Background

Primary ciliary dyskinesia (PCD) is generally a recessively inherited disorder characterized by dysfunction of motile cilia. A mutation in a new causative gene (CCDC39) has been identified in the Old English Sheepdog (OES).

Objectives

To describe the clinical findings and the molecular changes of affected dogs and estimate the worldwide prevalence of the mutation in a large cohort of OES.

Animals

578 OES, including 28 affected and 550 clinically healthy dogs.

Methods

This retrospective study reviewed the data of OES diagnosed with PCD and OES tested for the mutation. Clinical data including results of physical examination and further investigations were obtained on 11/28 dogs. CCDC39 expression was assessed by qRT‐PCR and Western blot analysis in affected dogs and healthy dogs. DNA was extracted on 561/578 dogs and a genetic test by Taqman technology was developed to genotype the CCDC39 mutation in these dogs.

Results

Clinical findings were recurrent nasal discharge and cough, pyrexia, leucocytosis, and bronchopneumonia. Ultrastructural defects were characterized by central microtubular abnormalities and decreased number of inner dynein arms (IDAs). Molecular analysis revealed a reduced expression of CCDC39 RNA and an absence of CCDC39 protein in affected dogs compared to healthy dogs. The mutation was more frequent in nonrandomly selected European OES population with a higher proportion of carriers (19%) compared to non‐European dogs (7%).

Conclusion and Clinical Importance

CCDC39 mutation is dispersed in a worldwide population and is responsible for PCD in this breed. Genetic testing might enable control of this disease.     

Tumour of the Epithelium of the Ciliary Body in a Dog

Abstract— —Tumours of the ciliary epithelium in the dog can be diagnosed clinically, because they are circumscribed and have a characteristic pink colour.
A case is described in which the histological structure corresponds to the adult medullo-blastoma in man.
It is suggested that some pigment in an intraocular tumour is no proof that the tumour originates necessarily from a pigment-forming tissue.
Résumé— —Les tumeurs de l'épithélium ciliaire, chez le chien, peuvent être diagnostiquées clinique-ment parce qu'elles sont circonscrites et ont une couleur rose caractéristique. Un cas dont l'aspect histologique est comparable à celui de médullo-blastome de l'homme est décrit.
Il est avancé que la présence de pigments en petites quantités dans une tumeur intra-oculaire ne suffit pas à prouver que la tumeur provient d'un tissu formant des pigments.
Zusammenfassung— —Die klinische Diagnose von Tumoren des Ziliarepithels beim Hund lässt sich aufgrund ihrer klaren Abgrenzung und der charakteristischen rosa Farbe stellen. Es wird ein Fall beschrieben, in dem der histologische Befund dem eines Erwachsenen-Medulloblastoms beim Menschen entspricht.
Es wird darauf hingewiesen, daß die Anwesenheit von Pigment in einem intraokularen Tumor keineswegs beweist, daß dieser Tumor seinen Ursprung in pigmentbildendem Gewebe hat.     

Fanconi's Syndrome in a Dog With Primary Hypoparathyroidism

An 11 -year-old castrated male mixed breed dog was referred for evaluation of muscle twitching, polyuria, polydipsia, anorexia, and periocular alopecia. Primary hypoparathyroidism was diagnosed by documenting decreased serum concentrations of parathyroid hormone and ionized calcium. Neurological, gastrointestinal, and dermatological signs resolved after calcium repletion. Initially, 1,25-dihydroxycholecalcif erol PO was required to correct the hypocalcemia. Dihydrotachysterol, in combination with oral calcium supplementation, was used for long-term maintenance of normal serum calcium concentration. Aminoaciduria, glucosuria, and hyperchloremic metabolic acidosis were consistent with a diagnosis of Fanconi's syndrome. This diagnosis was further supported by the presence of hypokalemia and increased urinary fractional excretion of sodium, potassium, calcium, phosphorus, and magnesium. Renal tubular dysfunction resolved after oral supplementation with calcium and vitamin D₃. Fanconi's syndrome in this dog may have been caused by decreased serum concentration of 1,25-dihydroxycholecalciferol, which was secondary to decreased parathyroid hormone production.     

Primary Gastric Carcinoma of the Dog: Review and Case Report

A case of a gastric adenocarcinoma in a ten year old neutered female Terrier of mixed breeding is presented. History, signs and pathology were typical of gastric carcinoma. However, the tumor was located in the distal one-third of the body of the stomach along the greater curvature rather than the more commonly involved pyloric antrum. The tumor was treated by surgical excision with a 7 month survival time. The surgical technique utilized is described and a discussion of canine gastric carcinoma is given.     

Arthroscopy in the Dog

Veterinary Research Communications -     

Ischemic Optic Neuropathy in a Dog with Acute Bilateral Blindness and Primary Systemic Hypertension

A 6‐year‐old neutered female Jack Russell terrier was investigated for sudden onset prechiasmatic bilateral blindness, left circling, reduced proprioception in the right pelvic limb and right facial allodynia. Electroretinography was normal. Magnetic resonance imaging (MRI) examination revealed that the right optic nerve and the optic chiasm were hyperintense on diffusion weighted imaging and hypointense on apparent diffusion coefficient map consistent with ischemic optic neuropathy. A concurrent lacunar infarct was detected in the left rostral colliculus. Primary systemic hypertension was diagnosed based on blood pressure measurement and no detectable abnormalities on hematology, comprehensive serum biochemistry, urinalysis including protein/creatinine and cortisol/creatinine ratios and thoracic/abdominal imaging. Prednisolone for 10 days and amlodipine long‐term were administered. Vision was not recovered after 7 months. Repeat MRI supported the diagnosis of ischemic lesions and revealed a recent striatocapsular infarct. Ischemic optic neuropathy is a well‐recognized cause of blindness in humans and should be included as a differential diagnosis for acute prechiasmatic blindness in dogs.     

Cerebral Angiography in the Dog

Abstract— The literature on cerebral angiography has been reviewed with the aim of developing a technique that can be used as an aid to ascertain the neuro-anatomical localization of intracranial tumours in the dog. Information has been gained from cerebral angiography in man, toxicity experiments on contrast media in cats and dogs, and all the available literature on cerebral angiography in the dog. Anatomy, techniques of injection, and complications, have been included.
Using concentrated contrast media in small quantities (1 ml) good angiograms of the anterior cerebral circulation can be obtained, and with larger quantities (up to 10 ml) all of the cerebral arteries have been demonstrated. No venograms have been obtained.
In most reports expensive cassette changers have been used, but single exposures can produce equally good results.     

Testicular Descent in the Dog

The mechanism underlying the process of normal testicular descent in the dog has been examined by a morphological, histological and histochemical analysis of testis and gubernaculum during the period from the 53rd day post coitum (p. c.) until the 40th day post partum (p. p.). Within this period, the testis passes the inguinal canal on the third or fourth day p. p. and reaches its scrotal location on the 35th day p. p. During the entire period the histological composition of the testis (volume percentage of seminiferous tubules, volume percentage of Leydig cells, diameter of seminiferous tubules, number of germ cells) is fairly constant. The △⁵-3β-hydroxysteroid dehydrogenase activity in the Leydig cells before birth suggests a steroid synthesis. Outgrowth and swelling of the gubernaculum occurs until the fifth day p. p. but morphological, histological and histochemical data indicate an onset of gubernacular regression during the last phase of the outgrowth reaction. The migration of the testis from the caudal end of the kidney towards the inguinal canal is associated with the outgrowth of the gubernaculum; during the phase of gubernacular regression, the testis moves from the inguinal canal towards its ultimate location in the scrotal pouch.