Modern veterinary practice最新文献

Though the microscopic agglutination test is commonly used as an aid to diagnosis of leptospirosis, it lacks sensitivity, cannot differentiate vaccinal titers from those of infection, and cannot identify shedders. The ELISA is sensitive but also cannot differentiate titers of vaccination and infection. Leptospire isolation is essential for a final diagnosis. Tissue or fluid samples should be aseptically collected, if possible, and quickly shipped to the diagnostic laboratory in transport medium or on ice, but should not be frozen. Samples to be collected may include urine, milk, kidney, aqueous humor, and fallopian tube or uterine mucosa.

Myeloproliferative disorders, a complex of cytologic abnormalities arising in the bone marrow, are among domestic animals most frequently recognized in cats but are relatively uncommon. A 4-year-old female Siamese, with splenomegaly and weight loss, was listless, anorectic, pale and dehydrated. A hemogram showed severe, macrocytic normochromic anemia, leukocytosis and reticulocytosis, with abnormally high numbers of nucleated RBC and undifferentiated blast cells. Bone marrow smears contained predominantly undifferentiated blast cells, RBC precursors and myeloblasts. The fluorescent antibody test for FeLV was positive. The cat died 66 days later despite a blood transfusion and chemotherapy. Necropsy confirmed a diagnosis of myeloproliferative disease, with hepatic and splenic invasion.

Ventricular septal defect (VSD) generally occurs high in the membranous septum rather than lower in the muscular portion. The English Bulldog and Siberian Husky may be predisposed. Clinical signs include a holosystolic or crescendo-decrescendo murmur best heard low on the right side at the 3rd-4th intercostal space and, with large defects, pulmonary congestion, exercise intolerance, cyanosis and ascites. The ECG is normal unless the right ventricle is hypertrophied, which causes right axis deviation and other electrocardiographic signs of right-sided heart enlargement. Plain film thoracic radiographs reveal signs of right-sided heart enlargement but often are not diagnostic. Nonselective angiocardiography is often not useful in diagnosing VSD with a left-to-right shunt of blood. Selective angiocardiography, in which contrast medium is injected directly into the left ventricle via a catheter, is the method of choice for diagnosis of VSD. Dogs with a small VSD remain asymptomatic, but those with large defects require surgical correction with a prosthetic septal pathic or pulmonary artery band.

Volvulus and incarceration of bowel by a hernia may cause a closed-loop obstruction, possibly with associated intramural accumulation of gas and/or blood. Standing lateral projections optimize diagnosis of strangulating obstructions. Accumulation of only fluid in the obstructed loop may resemble a tumor. Radiographic signs of exudation and peritoneal fluid accumulation may develop with closed-loop obstructions.

Feline demodicosis, caused by Demodex cati, may be associated with immunosuppression, as from FeLV infection or diabetes mellitus. Clinical signs include nonpruritic alopecia, scaling, erythema and hyperpigmentation in the facial region. Local topical application of 2.5% lime sulfur solution every 10 days is usually curative in a few weeks or months.

A group of grain-fed heifers became stiff, and some sternally recumbent, upon exercising after winter confinement. All but 2 affected heifers gradually recovered after IM injections of Se-vitamin E and IV infusion of Ca-Mg solution. Though serum assays failed to detect low Se levels, the presumptive diagnosis was based upon clinical signs and a good response to Se-vitamin E treatment.

Rhodococcus (Corynebacterium) equi pneumonia is diagnosed by thoracic auscultation, radiographic and hematologic examination, and transtracheal aspiration. Treatment may be unsuccessful because of the organism's tendency to cause pulmonary abscesses. A 2-month-old, depressed, anorectic, febrile Quarter Horse colt, previously unresponsive to penicillin therapy, had loud, moist breath sounds in the ventral lung fields. Chest radiographs revealed pneumonia. Based on culture and sensitivity tests on organisms isolated from transtracheal washes, chloramphenicol and erythromycin, and then oral trimethoprim-sulfadiazine, were given, in addition to supportive therapy. The animal was fully recovered within 2 months.

Though tracheal injuries often appear only superficial, exploration may reveal severe lacerations or fractures of the cartilaginous rings. A thorough physical examination and thoracic radiographs should precede tracheal surgery. Severe tracheal trauma is best repaired by partial resection and primary end-to-end anastomosis. Tension-relieving sutures aid healing of the anastomotic area, which is closed with synthetic absorbable sutures with extraluminal knots. Tracheal collapse, which primarily occurs in small or toy breeds, causes inspiratory dyspnea and can be corrected with polypropylene prostheses. Permanent tracheostomy may be required with laryngeal paralysis or irreparable tracheal injuries.

In a 2-year study of 49 Oklahoma cattle with a typical history of clinical endoparasitism, 12 animals had Ostertagia only, and Ostertagia was the predominant endoparasite in 21. Only 1 animal had a pure Haemonchus population. Though primary endoparasitism was diagnosed antemortem in 32 animals, postmortem worm counts confirmed the diagnosis in only 19. Worm counts documented inapparent disease in 8 animals. In 21 cases of suspected of toxicosis, 12 animals had endoparasitism none was poisoned.