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971.
OBJECTIVE: To report use of ultrasonographic examination of the coxofemoral joint, a surgical technique for repair of craniodorsal coxofemoral dislocation, and outcome. STUDY DESIGN: Clinical case reports. ANIMALS: Calves (n=4) with coxofemoral luxation. METHODS: Craniodorsal coxofemoral luxation was diagnosed by physical examination, radiographic, and ultrasonographic findings. Open surgical reduction of the femoral head was performed using a modified caudal approach. RESULTS: Craniodorsal luxation of the femoral head and the presence of an intact femoral neck were confirmed by ultrasonography. All luxations were successfully reduced and reluxation did not occur. At follow-up, 1 heifer had calved and 1 was 5 months pregnant. One calf died of bronchopneumonia 6 days after surgery. One calf had severe coxofemoral degenerative joint disease diagnosed (ultrasonography, radiography, and arthrocentesis) 3 months after surgery and confirmed by necropsy. CONCLUSION: Ultrasonography proved to be a simple and effective non-invasive technique for diagnosis of coxofemoral luxation. Immediate surgical intervention in hip dislocation in calves is necessary to avoid unnecessary trauma to subchondral structures. In calves, open instead of closed surgical reduction appears preferable because it allows access to the acetabular cavity for removal of debris. CLINICAL RELEVANCE: Ultrasonography should be considered a supplementary but not an alternative to radiographic examination for diagnosis of coxofemoral luxation and for follow-up examinations after reduction.  相似文献   
972.
BACKGROUND: Knowledge of breed associations is valuable to clinicians and researchers investigating diseases with a genetic basis. HYPOTHESIS: Among symptomatic dogs tested for exocrine pancreatic insufficiency (EPI) by canine trypsin-like immunoreactivity (cTLI) assay, EPI is common in certain breeds and rare in others. Some breeds may be overrepresented or underrepresented in the population of dogs with EPI. Pathogenesis of EPI may be different among breeds. ANIMALS: Client-owned dogs with clinical signs, tested for EPI by radioimmunoassay of serum cTLI, were used. METHODS: In this retrospective study, results of 13,069 cTLI assays were reviewed. RESULTS: An association with EPI was found in Chows, Cavalier King Charles Spaniels (CKCS), Rough-Coated Collies (RCC), and German Shepherd Dogs (GSD) (all P < .001). Chows (median, 16 months) were younger at diagnosis than CKCS (median, 72 months, P < .001), but not significantly different from GSD (median, 36 months, P = .10) or RCC (median, 36 months, P = .16). GSD (P < .001) and RCC (P = .015) were younger at diagnosis than CKCS. Boxers (P < .001), Golden Retrievers (P < .001), Labrador Retrievers (P < .001), Rottweilers (P = .022), and Weimaraners (P = .002) were underrepresented in the population with EPI. CONCLUSIONS AND CLINICAL IMPLICATIONS: An association with EPI in Chows has not previously been reported. In breeds with early-onset EPI, immune-mediated mechanisms are possible or the disease may be congenital. When EPI manifests later, as in CKCS, pathogenesis is likely different (eg, secondary to chronic pancreatitis). Underrepresentation of certain breeds among dogs with EPI has not previously been recognized and may imply the existence of breed-specific mechanisms that protect pancreatic tissue from injury.  相似文献   
973.
Carbadox is known to induce toxic effects on the adrenal cortex, resulting in hypoaldosteronism. To study the involvement of carbadox on the renin-angiotensin system, weaned piglets of five weeks old received feed supplemented with 0 (control group), 50, 100, 150 or 200 ppm carbadox. After four weeks the 100 and 150 ppm groups had significantly higher plasma renin activity levels than the control group and after nine weeks plasma renin activity levels of all treated groups were significantly higher than the control group. Five and 10 weeks after carbadox administration, three and two pigs, respectively, of all groups were necropsied and the kidneys were screened for immunohistochemically demonstrated renin. All dosed pigs demonstrated an increase of immunoreactive renin, which was dose- and time-related. From these results it is concluded that carbadox induces activation of the renin-angiotensin system, secondary to the suppressing effect on mineralocorticoid secretion and that these changes may be responsible for part of the clinical picture.  相似文献   
974.
One hundred thirty-eight swine abortions were studied in detail in an effort to identify an etiologic agent. A viral agent was implicated in 7 cases. Bacteria were isolated in less than half of the examined cases: however, in 61% of the cases, motile, filamentous organisms were observed in tissues and fluids. Although swine sera from farms experiencing reproductive problems had a high reactor rate to Leptospira bratislava antigen, electron microscopy of the observed organism revealed a wall-free prokaryote morphologically typical of the class Mollicutes.  相似文献   
975.
Clinical experience of 73 cases of necrobacillosis in red-necked wallabies (Macropus rufogriseus) over a 6-year period is reviewed. Diagnostic methods and the medical and surgical treatment options are detailed. It is suggested that survival curves are necessary to assess the outcome of treatment.  相似文献   
976.
A procedure established for the selective isolation of the species of Streptococcus responsible for rainbow trout streptococcosis in South Africa, consisted of the inoculation of samples into nutrient broth which had been supplemented with 100 micrograms/ml of nalidixic acid, 160 micrograms/ml of oxolinic acid or 200 micrograms/ml of sodium azide. After incubation, the sample was plated onto tetrazolium agar on which the rainbow trout pathogenic Streptococcus species grew as a red colony. The colonies were isolated from the tetrazolium agar and identified as rainbow trout pathogenic isolates by biochemical and serological tests. In the laboratory the selective procedure is capable of detecting about 2 bacteria per ml. This procedure was used in the field and biochemically identical Streptococcus species were found in the mud and a freshwater crab from the water source of a site with a history of streptococcosis.  相似文献   
977.
978.
979.
The effect of colostrum on endocrine and metabolic factors affecting glucose homeostasis was evaluated in 60 neonatal pigs that were fasted, fed (nursed ad libitum) or limit-fed colostrum (25% ad libitum, 4-hr interval feeding). Plasma acquired at birth (t0), and after 10, 20 and 30 hr (t10, t20 and t30, respectively) was analyzed for glucose, non-esterified fatty acids (NEFA), and the glucoregulatory hormones--insulin, glucagon, cortisol, growth hormone and catecholamines. The concentration of glucose and NEFA was similar among treatment groups at birth and increased in proportion to the quantity of colostrum consumed. Pigs fed ad libitum achieved and maintained a higher (greater than or equal to 40%; P less than .01) glucose concentration when compared to fasted neonates. Limit-fed counterparts also achieved and maintained higher levels, with glucose concentration being approximately 20% higher throughout (P less than .05). Fed pigs maintained NEFA concentrations which were approximately 2.5-fold to 4-fold greater than that of fasted pigs (P less than .05). Likewise, limit-fed pigs tended (P = .19) to have elevated NEFA concentrations and a lower (P less than .05) insulin:glucagon molar ratio. An inverse relationship was observed between colostrum intake and plasma concentrations of cortisol and growth hormone. Concentrations of epinephrine and norepinephrine tended (P greater than .10) to be elevated in fed pigs, relative to those of fasted counterparts. Provision of even limited quantities of colostrum is therefore beneficial to the glucoregulatory response in newborn pigs.  相似文献   
980.
We evaluated the deformability of bovine platelets and contrasted the effects of pharmacologic and thermal perturbations on cytoskeletal structure of human and bovine platelets. Platelets were aspirated into micropipettes (0.7 to 0.8 micron in diameter) by stepwise increments in tension. The resulting lengths of the cell extensions were recorded. The cell extensions aspirated from bovine platelets were shorter than the extensions drawn from human platelets. Disassembly of the circumferential microtubule coil allowed human platelets to pass through the pipette, but the same treatments only slightly increased the deformability of bovine platelets. Alteration of the actin filament cytoskeleton caused increased mechanical fragility of human platelets. In contrast, even the combined use of microtubule and actin filament-disrupting agents only modestly increased the deformability of bovine platelets and did not cause premature fragmentation of the cells. Unusual cytoskeletal structure, absence of an open canalicular system, and disparity in granule size may all contribute to the variance in deformability between the platelets of the 2 species. Reduced cell deformability may impair bovine platelet surface interactions by diminishing the ease of cell spreading and formation of areas of contact between the platelet and other cell surfaces.  相似文献   
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