Tag Archives: Greyhound

Congenital Deafness

Deafness that is present at or soon after birth may have either an acquired or a hereditary etiology and may occasionally occur in any puppy whether pure bred or mixed breed. Acquired deafness may be caused by viral infections, anoxia, or the ototoxic side effects of drugs or other materials. Because dogs and cats are born deaf, deafness in a puppy or kitten is not abnormal up to a certain age. In cats the earliest discriminating hearing tests were performed at the age of 7 days. Cochlear potential measurements from a round-window electrode were found to be conclusive about the presence or absence of hearing in cats over 7 days of age (). In dogs, hearing tests were performed from the age of 4 weeks () by means of cochlear potential measurements from round-window electrodes () or brainstem auditory evoked responses (BAERs) (). Testing the Hearing of Young Puppies In our laboratory, two Irish wolfhound puppies and two beagle puppies were investigated for hearing from the third day after birth. Brain-stem auditory evoked potentials (BAERs) were recorded from surface electrodes (Dantec) on the pinnae and the skin over the parietal bone on the midline. For the recording of air-conducted BAERs, each pup was placed in a Read more […]

Subcutaneous Mycoses

infection by fungi of viable skin, often traumatically induced very rare in the UK examples include eumycotic mycetoma, phaeohyphomycosis, pythiosis, protothecosis and sporotrichosis identification of these fungi should be undertaken only by an experienced veterinary mycologist Eumycotic mycetoma rare in dogs and cats trauma-induced, may involve the skin, subcutaneous tissue, fascia and bone causal fungi include Allescheria boydii and Curvularia geniculata causal actinomycetes include Actinomyces and Nocardia Clinical features frequently there is a triad of swelling, draining fistulae and granules usually localized lesion, typically on a foot may be painful and swollen Diagnosis culture on plain Sabouraud’s agar histopathology: demonstration of fungal elements with specialized stains such as PAS Differential diagnosis abscesses foreign body reactions neoplasms Treatment radical surgical excision there is no effective medical therapy Phaeohyphomycosis mainly cats, a few cases have been reported in dogs rare causal fungi in cats include Drechslera spicifera, Phialophora verrucosa, Moniella suaveloens and Exophiala jeanselmii causal fungi in dogs Read more […]

General Anaesthesia in Geriatric Patients

Preparation Animals should be fasted for 12 hours, with water being withdrawn 1-2 hours beforehand. Water deprivation in old animals can precipitate a uraemic crisis so overnight deprivation is not recommended if there is evidence of renal incompetence and an i.v. fluid line should be established before the administration of a sedative or anaesthetic. All patients should be weighed before computation of drug dosages to avoid errors. If the animal is obese the lean body weight should be estimated. Premedication Acepromazine can be given in low doses (0.02-0.05 mg/kg i.m.) but should not be used in the presence of cardiovascular disease such as endocardiosis and congestive heart failure, as it can cause rapid hypotension. Acepromazine should also be avoided in dogs prone to seizures, and it is contraindicated in the presence of renal impairment. Intravenous administration can cause profound hypotension and it should only be used by this route with great care. The author has witnessed a geriatric dog collapsing and dying immediately following the intravenous administration of acepromazine. Xylazine and medetomidine should only be used with extreme care in geriatric canine and feline patients because they can cause Read more […]

Respiratory System

The respiratory system (apparatus respiratorius) uses the nose, nasal cavity, pharynx, larynx, trachea, bronchi, and smaller passageways to bring air to the alveoli or sites of gaseous exchange within the lungs. Various structures associated with these passageways modify or regulate the flow of air, serve as olfactory receptors, facilitate water and heat exchange, and make phonation possible. The nasal cavity and the conchae (also called turbinates) warm and moisten the air and remove foreign material. The pharynx serves as a passageway for both the respiratory and the digestive systems. The larynx guards the entrance to the trachea, functions in vocalization, and regulates both the inspiration and the expiration of air. The trachea is a cartilage-reinforced tube lined by ciliated epithelium. It divides into principal bronchi and continues into the two lungs as lobar bronchi, segmental bronchi, bronchioles, alveolar ducts, alveolar sacs, and alveoli. The terminal divisions are located in the elastic, well-vascularized lungs, which passively expand and collapse in response to changes in intrathoracic pressure, created by the action of the muscles of the diaphragm and thoracic wall. The nose (nasus), in a broad Read more […]

Lungs

The lung (pulmo) () is the organ in which oxygen from the atmosphere and carbon dioxide from the blood are exchanged. The lungs serve a passive function in the mechanical act of respiration. The diaphragm, when it contracts, enlarges the pleural cavity by moving caudally. When the intercostal muscles contract and draw the ribs cranially, the size of the thoracic cavity is also increased, and thus air is drawn into the lungs because of the negative pressure that is produced. Aiding in expulsion of the air from the lungs are the abdominal muscles, which contract and force the abdominal viscera against the caudal surface of the diaphragm. The efects of age on lung function and structure were reviewed by Mauderly and Hahn (1982). In general there is considerable fibrosis and loss of function in the lungs of old dogs. Robinson (1982) summarized some functional consequences of species diferences in lung anatomy. There is no explanation for the great variation seen in lung lobation of domestic and wild mammals. The two lungs (pulmo sinister et dexter) possess many features in common. Each has a slightly concave base (basis pulmonis), which lies adjacent to the diaphragm, and an apex (apex pulmonis), which lies in the thoracic Read more […]

Hypertrophic cardiomyopathy

The incidence of primary (idiopathic) hypertrophic cardiomyopathy (HCM) is much lower in dogs than it is in cats. Males appear to be predominantly affected and there may be a higher incidence in boxers and German shepherd dogs. The disease is characterized by hypertrophy of the left ventricular free wall and interventricular septum. The aetiology of primary hypertrophic cardiomyopathy has not been determined. Pathophysiology Myocardial hypertrophy results in decreased left ventricular compliance (increased myocardial *stiffness*) and diastolic dysfunction. Systolic function is usually adequate. Myocardial hypertrophy results in increased myocardial tension and afterload. This in turn leads to progressive myocardial isehaemia and the development of cardiac arrhythmias which are usually ventricular in origin. In most cases the hypertrophy is asymmetric with disproportionate thickening of the inter ventricular septum compared to the left ventricular free wall (at necropsy, septal to left ventricular free wall ratio in affected cases is greater than 1.1:1). Asymmetric hypertrophy may cause functional left ventricular outflow obstruction. Ventricular hypertrophy may also be associated with focal or diffuse endocardial Read more […]

Testes

The testis, or male gonad (), is oval in shape and located within the scrotum. The length of the testis in a 25-pound dog averages 3 cm and the width 2 cm. The fresh organ weighs approximately 8 g. In normal position, the testis of the dog is situated obliquely, with the long axis running dorsocaudally. The epididymis is adherent to the dorsolateral surface of the organ, with its head located at the cranial end and its tail at the caudal extremity of the testis. The surface of the testis is invested by the tunica albuginea, a dense, white fibrous capsule. Covering the testis most immediately is the visceral vaginal tunic, a serous membrane continuous with the peritoneum of the spermatic cord and the abdominal cavity. The tunica albuginea joins the centrally located mediastinum testis by means of interlobular connective tissue lamellae (septula testis), which converge centrally. The mediastinum testis is a cord of connective tissue running lengthwise through the middle of the testis. The lobuli testes (wedge-shaped portions of testicular parenchyma) are bounded by the septula. The lobuli contain the convoluted seminiferous tubules (tubuli seminiferi contorti), a large collection of twisted canals. Spermatozoa are Read more […]

Inflammatory diseases

Infectious meningitis / meningomyelitis Meningitis (inflammation of the meninges) and meningomyelitis (inflammation of the spinal cord and the meninges) can cause severe spinal pain. Meningomyelitis, by definition, will also cause neurological deficits. Cerebrospinal fluid (CSF) analysis is the most reliable antemortem diagnostic test available for identifying CNS inflammation; it often reveals an increase in the white blood cell number as well as protein elevations. A complete discussion of the diagnosis, treatment and prognosis of infectious CNS disease is presented in site. Steroid-responsive meningitis-arteritis Clinical signs: SRMA, also termed necrotizing vasculitis, juvenile polyarteritis syndrome, corticosteroid-responsive meningitis / meningomyelitis, aseptic suppurative meningitis, panarteritis and pain syndrome, is a non-infectious inflammatory condition reported in Beagles, Bernese Mountain Dogs, Boxers and German Short-Haired Pointers (), and urobably occurs in other breeds. Affected dogs are often young adults (8-18 months : d) but may be of any age, and are usually febrile and hyperaesthetic, with cervical rigidity and anorexia (). Neurological deficits can be seen in the chronic form of this disease. Read more […]

Performance Dogs

After reproduction, work places the greatest nutritional demand on dogs. Dogs engage in guard and police work, racing, and hunting. Hard work increases all nutrient needs. For most “weekend athlete” dogs, these increases are proportional to the increase in energy needs, so they can be met by eating more of the same diet. Studies of sled dogs in the field and beagles on treadmills, however, have suggested that diets designed to support hard work and maximize stamina should have high digestibility and low bulk and should provide 50% to 60% of dietary energy from fat, 30% to 40% from protein, and 10% to 20% from carbohydrate. The digestibility of commercial dog foods ranges from approximately 70% to 85%. Food bulk — the fiber and mineral content — therefore represents 15% to 30% of the food. Increasing the fat content usually increases the digestibility of dry dog foods. Moreover, high-fat diets often are lower in mineral and plant fiber content. Reducing the bulk improves stamina by increasing nutrient density and reducing the volume of indigestible material in the colon. In studies comparing the influence of fat and carbohydrate on stamina in racing sled dogs, red blood cell mass responded to training and racing Read more […]

Facts about Hip Dysplasia

The highest incidence is found in giant, large and medium breeds, like Labrador Retriever. A Coxofemoral Joint Disease: Hip dysplasia is a potentially crippling disease affecting the coxofemoral joint, which is located between the pelvis and femur, or uppermost bone of the rear leg. Almost all canine breeds are susceptible to this inherited disorder, but its highest incidence is found in the giant, large and medium breeds that typically experience rapid growth early in life. For instance, Labrador Retrievers, Great Danes and German Shepherds can be prime candidates for developing hip dysplasia. Clinical signs of canine hip dysplasia usually begin to emerge between five to eight months of age, although they may be seen earlier or later in life. Their onset may be sudden in young dogs, whereas in the older dog they may become apparent either acutely or gradually. Generally, signs of hip dysplasia are compatible with pain originating from the hindquarters. Lameness of one or both hind legs may be encountered, for example, or alterations in the way the dogs stands or gaits. This may take the form of standing with an arched back to lessen the amount of weight carried by the hindquarters, or keeping the rear legs close Read more […]