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411.
Mathew J. Reeves Charles R. Curtis Mo D. Salman John S. Reif Ted S. Stashak 《Preventive veterinary medicine》1990,9(4):241-257
A survey of 1965 equine colic cases was conducted from August 1985 to July 1986 ten equine referral hospitals located througout the U.S.A. Two-thirds of the cases were randomly selected for model development (1336), while the remaining cases (629) were used only for subsequent validation of the model. The following outcomes were defined: (1) died or killed prior to discharge from the hospital; or (2) alive at the time of discharge. Only variables which were significant (P<0.05) in an initial bivariate screening procedure and for which there were less than 400 missing values were considered in the multivariable modelling. A multivariable logistic regression model was constructed using a stepwise algorithm. The model used 666 cases and included the following variables: peripheral pulse (normal or weak), pulse rate, surgical or medical treatment, packed cell volume, self-inflicted trauma (absent or present) and capillary refill time. For each horse in the validation data set which had the appropriate variables recorded (n=335), the estimated expected probability of death (expected value) was calculated using the logistic regression equation. Using Bayes theorem, the post-test probability was calculated from the expected value (an estimate of the test odds) and the present probability (the case-fatality rate at each institution). Nomograms of predictive values for different case-fatality rates and expected values were constructed. Hosmer-Lemeshow goodness-of-fit statistics indicated that the model fitted the model data set well but the validation set poorly. However, when the observed case-fatality rates were compared with the average post-test probabilities for 0.10 increments of post-test probability, qualitatively, the model's performance was better. 相似文献
412.
Sarah A. Slaughter Andrew D. Eitzer Sara E. Tolliver Sarah N. Holman Sara A. Colopy Seamus E. Hoey Samantha J. Loeber 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(5):515
A 14-week-old male unilaterally cryptorchid Clumber spaniel was presented for acute lethargy. Physical examination revealed abdominal pain, and a single testis was palpated in the scrotum. Abdominal ultrasound and computed tomography (CT) revealed a poorly vascularized, ovoid structure immediately caudal to the left kidney with scant regional peritoneal effusion. Left intra-abdominal testicular torsion was confirmed at surgery, and routine cryptorchidectomy was performed. The patient recovered uneventfully from anesthesia and surgery.Key clinical message:The most common CT characteristics of testicular torsion were present in this case and correlated well with sonographic findings to allow for rapid, accurate diagnosis and surgical planning of unilateral, non-neoplastic, intra-abdominal cryptorchid testicular torsion in a juvenile dog. Contrast enhanced CT facilitated accurate localization of the undescended testis and evaluation of testicular perfusion and may be a useful alternative to ultrasound for diagnosing testicular torsion, especially in indeterminate cases. 相似文献
413.
McClenahan D Fagliari J Evanson O Weiss D 《American journal of veterinary research》2000,61(5):492-498
OBJECTIVE: To determine the capacity of inflammatory mediators tumor necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8), platelet-activating factor (PAF), lipopolysaccharide (LPS), and leukotoxin to prime, activate, or alter deformability of adult bovine neutrophils. SAMPLE POPULATION: Blood collected from 5 healthy adult Holstein cows. PROCEDURE: Isolated neutrophils or whole blood was incubated with TNF-alpha, IL-8, PAF, LPS, or leukotoxin, and neutrophil chemiluminescence, degranulation, deformability, shape change, CD11b expression, and size distribution was measured. RESULTS: Incubation with TNF-alpha, IL-8, PAF, and LPS primed neutrophils for oxygen radical release but caused minimal oxygen radical release by themselves. None of the inflammatory mediators induced degranulation. Incubation with TNF-alpha and PAF resulted in a decrease in neutrophil deformability and induced shape change in neutrophils. Incubation with PAF consistently resulted in an increase in neutrophil size as measured by use of flow cytometry. Only IL-8 caused an increase in expression of CD11b by neutrophils. CONCLUSIONS AND CLINICAL RELEVANCE: Inflammatory mediators tested had minimal effects on neutrophil oxygen radical production or degranulation but did prime neutrophils for oxygen radical production. Incubation with PAF and TNF-alpha caused a decrease in neutrophil deformability and altered neutrophil shape and size. Results of our study indicate that PAF- and TNF-alpha-induced changes in neutrophil deformability and size may cause integrin- and selectin-independent trapping of neutrophils in the lungs of cattle with pneumonic pasteurellosis. 相似文献
414.
Das A Katole S Kumar A Gupta SP Saini M Swarup D 《Journal of animal physiology and animal nutrition》2012,96(3):442-449
A feeding trial was conducted to determine the optimum level of crude protein (CP) in the diet of captive blackbuck (Antelope cervicapra) in which feed consumption and nutrient utilization are maximal. Fifteen blackbucks (BW 25-34 kg) were distributed into three groups of five each in an experiment of 75-days duration including a digestion trial of 5-day collection period. All the animals were offered 200 g of concentrates and fresh maize fodder ad libitum. The overall CP content of the three respective diets was 6.9%, 10.4% and 12.7%. Blood samples were collected on the last day of the experiment. Intake and digestibility of CP increased (p < 0.01) with the increased level of CP in the diet. Feed consumption and nutrient intake were not significantly different among the groups. However, digestibilities of most of the nutrients were higher in the 10.4% CP diet than in the 6.9% CP diet. The endogenous loss of nitrogen was similar among the groups. Based on the endogenous losses, minimum N requirement was calculated to be 776 mg/kg BW(0.75) /day, and to meet this requirement, diet must contain at least 8.27% CP. Serum urea nitrogen concentration increased (p < 0.01) with increased level of dietary CP. Serum level of glutamate oxaloacetate transaminase and glutamate pyruvate transaminase was higher (p < 0.05) in the group fed 6.9% CP diet. Animals in the group fed low protein diet also lost body mass during the experimental period. It was concluded that a diet containing 10.4% CP was optimum for maximizing nutrient utilization without any adverse effect on voluntary feed consumption and serum metabolite profile of blackbucks. 相似文献
415.
M. Yaeesh Siddiqi Bhupinder Malhotra Xiangjia Min Anthony D. M. Glass 《植物养料与土壤学杂志》2002,165(2):191-197
Effects of varying the proportions of NO3— and NH4+ in the growth medium on seedling growth and tomato fruit yield (Lycopersicon esculentum L. cv. Trust F1) were investigated in greenhouse hydroponic experiments. The presence of NH4+ as the sole N source (11 mM) was toxic: it curtailed growth and decreased chlorophyll content of the leaves. However, at low concentration (10 % of total N), the presence of NH4+, with or without added dissolved inorganic carbon (DIC), increased vegetative growth and fruit yield by ˜ 15 %, and enhanced taste/flavor of the fruits. In DIC‐enriched treatment, pH was maintained at 5.8 by addition of KHCO3 or as CaCO3. The presence of NH4+, at 10 % of total N, inhibited NO3— uptake rates by ˜ 27 %. The rates of uptake of NO3— and NH4+ were comparable (13.3 and 14.2 mmol plant—1 d—1, respectively, in the presence of DIC, and 14.7 and 14.0 mmol plant—1 d—1, respectively, in the absence of DIC), despite such a large difference in their concentrations in the nutrient feed solution. A higher proportion of NH4+ (up to 50 % of total N) had no further significant effect upon early vegetative growth, but in a long‐term experiment resulted in a high incidence of blossom end‐rot (BER) disease, thereby severely curtailing fruit yield. The presence of even 1.1 mM NH4+ reduced Ca2+ and Mg2+ accumulation in the leaves as well as in fruits. 相似文献
416.
E Stalber H W Renshaw C Boro D Mattson F W Frank 《Canadian journal of veterinary research》1976,40(1):98-103
A viral agent, designated Id-1, was isolated from the buffy coat of a calf suffering from weak calf syndrome. The virus replicated on bovine salivary gland cells and caused cytopathic effect within four days after infection-Cytopathic effect was characterized by rounding and clumping of cells. Stained preparations of infected monolayers revealed multiple intranuclear inclusions. The agent was found to be resistant to chloroform, ether, trypsin, sodium desoxycholate, oxytetracycline and a pH range of three to nine. The virus was sensitive to 5-iodo-2'-deoxyuridine and to a temperature of 70 degrees C. Cross neutralization tests with Id-1 antiserum and bovine adenovirus type 7 (strain Fujuroi) antiserum resulted in complete neutralilation of both viruses with four or less antibody units of homologous or heterologous antiserum. 相似文献
417.
418.
Gabriel A Poncelet L Van Ham L Clercx C Braund KG Bhatti S Detilleux J Peeters D 《The Journal of small animal practice》2006,47(3):144-149
OBJECTIVES: To characterise clinical, electrophysiological and histopathological findings. To analyse pedigree information in six young related Pyrenean mountain dogs with laryngeal paralysis-polyneuropathy complex (LP-PNC). METHODS: A retrospective study of clinical records and pedigrees of six young related Pyrenean mountain dogs with LP-PNC was carried out. RESULTS: All dogs were presented with laryngeal paralysis and concurrent megaoesophagus. Electrodiagnostic testing was performed in three dogs and showed electrophysiological abnormalities in the distal appendicular muscles. Histopathological findings of peripheral nerve samples were dominated by distal axonal degeneration. Clinical, electrophysiological and histopathological findings were supportive of a diagnosis of degenerative, sensorimotor LP-PNC, similar to that reported in young dalmatians and rottweilers. All dogs died or were euthanased by two years of age. An autosomal recessive mode of inheritance was suspected based on pedigree analysis. CLINICAL SIGNIFICANCE: Congenital LP-PNC should be suspected in any young dog presenting with laryngeal dysfunction and other concurrent neurological abnormalities. The prognosis is usually poor. 相似文献
419.
420.
M D Bishop M E Davis W R Harvey G R Wilson B D VanStavern 《Journal of animal science》1991,69(11):4360-4367
A single generation divergent selection study, replicated four times (1983, 1984, 1985, and 1986), was conducted to assess genetic differences between progeny of high and low feed conversion sires in Angus beef cattle and to determine correlated response for weight gain (ADG140), feed intake (AVFD140), and BW (OFFTSTWT) in a time- (140-d) and fat-constant (8.9 mm) period. Realized heritability estimates for unadjusted (feed/gain; FEFF140; .26) and adjusted feed conversion (adjusted as recommended by the BIF, 1986; ADJFDEFF; .46) were obtained. The difference in heritability estimates reflects variation accounted for by adjustment for BW differences, and thus maintenance requirements, of individual progeny. Phenotypic and "pseudo" realized genetic correlations of FEFF140 with ADG140, AVFD 140, and OFFTSTWT were -.33 and -.66, .49 and -.26, and .15 and -.41, respectively. Phenotypic and "pseudo" realized genetic correlations of ADJFDEFF with ADG140, AVFD140, OFFTSTWT, and FEFF140 were -.54 and -.59, .30 and -.23, .27 and -.36, and .97 and .49, respectively. Subcutaneous fat (as estimated by ultrasonic measurement; BF140) had phenotypic and "pseudo" realized genetic correlations with FEFF140 of -.33 and .66, respectively, and with ADJFDEFF of -.44 and -.58, respectively. 相似文献