Modern veterinary practice最新文献

A 9-month-old cat, presented for castration, lacked scrotal testes and a developed scrotum but had a normal penis. Normal testes were removed at celiotomy. The cat had a normal 38 XY karyotype. A 3-year-old cat, presented for cystotomy and urolith removal, had a vulva, a scrotum without testes and a 3-mm rudimentary penis. No castration scars were evident on the scrotum, and no testes could be located within the abdomen. Though a karyotype was not performed, it was presumed to be the normal 38 XY found in pseudohermaphrodites.

In horses with large bowel disease, those with circulating endotoxins but no evidence of altered hemostasis had a good prognosis for survival. Those with circulating endotoxins and evidence of altered hemostasis (fibrin degradation products) had a poor prognosis. Portal vein infusion of endotoxins over 24 hours caused hoof discomfort, evidenced by shifting of weight and standing with all 4 feet together, and a decreased hoof temperature. Clinical signs appeared within 30 minutes of initiation of infusion and subsided within 4 hours despite continued infusion. Long-term heparin therapy results in rapid depletion of RBC but no detectable bleeding. Heparin therapy should be initiated before colic surgery is begun. Coagulation is monitored with the activated partial thromboplastin time. Heparin should initially be given IV, followed by SC or intrafat injections, and should never be given IM. The anticoagulative effects of heparin can be reversed with protamine sulfate.

A 7-month-old Lhasa Apso with a history of polydipsia and vomiting was depressed, thin and dehydrated. Serum chemistry assays revealed hyperphosphatemia and azotemia, and urinalysis revealed isosthenuria, suggesting azotemia of renal origin. Antemortem renal biopsy specimens contained several sclerotic glomeruli, a few embryonic renal tubules and interstitial fibrosis, indicating renal dysplasia.

Respiratory minute volume, blood volume, RBC mass and cardiac output increase while the functional residual capacity decreases during late pregnancy. General anesthetics reach the fetus in high concentrations and tend to persist in the fetus after delivery. Use of small doses of a combination of anesthetics is recommended. Ephedrine increases vascular tone and cardiac output. Glycopyrrolate and fentanyl-droperidol are used to restrain sows for cesarean section. Morphine alone or with acepromazine works well in depressed sows. Acepromazine or xylazine, used with ketamine, is good in restraining small ruminants. A sedative and local blocks can be used in standing cows. Anesthesia in mares is induced with xylazine, guaifenesin and ketamine and maintained with halothane, guaifenesin or thiopental. Large doses of xylazine should be avoided. Lidocaine toxicity can result from overuse in local blocks.

A 9-year-old male German Shepherd had marked stumbling, staggering and weakness in both rear limbs. Pelvic radiographs revealed only mild hip dysplasia, while survey spinal radiographs and a myelogram revealed only areas of possible pachymeningitis. Results of CSF analysis were normal. Degenerative myelopathy was suspected, but a mitogen response assay failed to confirm this diagnosis. Another mitogen response assay, performed several months later, again failed to indicate degenerative myelopathy as the cause of clinical signs. The dog's condition worsened and the animal was euthanized. At necropsy, classic histopathologic lesions of degenerative myelopathy were noted in the thoracic spinal cord.

Pulmonic stenosis is caused by a malformed pulmonic valve, stricture of the right ventricular outflow tract or stricture of the pulmonary artery. English Bulldogs, Beagles, Samoyeds, Fox Terriers and Chihuahuas are predisposed. Clinical signs in severely affected dogs include exercise intolerance, stunting, dyspnea, syncope and ascites. Auscultation reveals a high-frequency, crescendo-decrescendo murmur during systole, loudest over the left side of the thorax, near the sternal cardiac border. An ECG may reveal a right-axis deviation of greater than 120 degrees, S waves in leads I, II and III, deep S waves in CV6LL, CV6LU and V10, Q waves deeper than 0.5 mv in leads II, III and AVF, and positive T waves in lead V10. Plain film LAT thoracic radiographs reveal an elevated carina, increased sternal contact of the heart, loss of the cranial cardiac waist and a widened cardiac silhouette, with normal pulmonary vasculature. A DV projection reveals an inverted "D" shape of the right ventricle and a pulmonary artery bulge. A nonselective angiocardiogram reveals poststenotic dilation of the main pulmonary artery. Treatment involves surgical correction of the stenosis.

A female Golden Eagle died despite intensive treatment after being struck by a vehicle. Necropsy revealed poor body condition, with no fat stores. The proventriculus and ventriculus contained a pellet of fur and bone fragments, at the center of which was the leg of a Red-Tailed Hawk. A talon on the leg had punctured the ventriculus, resulting in fatal pleuritis and peritonitis.

A 10-mm circumscribed nodule, containing hair, was noted on the ventral cornea, limbus and conjunctiva of the right eye of a 6-month-old male Hereford calf. With the animal restrained in a chute and proparacaine used as a topical anesthetic, superficial keratectomy was performed to remove the mass. The edge of the bulbar conjunctival wound was sutured to the limbus with 6-0 Vicryl. Chloramphenicol ophthalmic ointment was applied TID for 5 days. Recovery was uneventful.

The Kirschner-Ehmer splint can be used to treat open, infected or highly comminuted fractures, gunshot fractures, nonunions, delayed unions, mandibular fractures and angular deformities in association with osteotomy, as well as to immobilize joints and as an adjunct to other fixation devices. After the fracture is reduced, 2-4 percutaneous pins are inserted with a Jacobs hand chuck through one or both cortices at 45-60 degrees to the longitudinal axis of the bone and attached to a connecting bar with clamps. Complications are minimized by not inserting the pin through large muscle masses, the fracture hematoma, large blood vessels or the incision line, avoiding encroachment of soft tissue with the clamps, and restricting the animal's activity during healing.

The most common cause of hypoadrenocorticism in dogs is idiopathic immune-mediated destruction of the adrenal cortex. Other causes include anterior pituitary insufficiency, pituitary or adrenal neoplasia, acute withdrawal of exogenous corticosteroids, and mitotane toxicity. Females are affected more often than males; only 1 feline case has been documented. Animals 2-5 years old are most commonly affected. Clinical signs include lethargy, weakness, weight loss, anorexia, vomiting, diarrhea and bradycardia. Hematologic and biochemical changes can include eosinophilia, lymphocytosis, anemia, hyperkalemia, hyponatremia and hypercalcemia. Diagnosis is by finding negligible resting levels of plasma cortisol and no response to ACTH administration, and a serum Na:K ratio of 20:1 or less. Treatment involves restoring fluid volume, correcting acidosis, and supplementing salt and glucocorticoids. Daily oral use of prednisone at 0.05 mg/kg can safely maintain most affected dogs. Some dogs only require glucocorticoids in stressful situations. Iatrogenic secondary adrenocortical insufficiency (iatrogenic Cushing's disease) may result from a single injection of long-acting glucocorticoids or from long-term use. Clinical signs are the same as for natural hyperadrenocorticism, but endogenous cortisol release is suppressed. Treatment is gradual withdrawal of the offending glucocorticoid and elimination of the cause that initially prompted glucocorticoid therapy.