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41.
A total of 2238 feline serum samples submitted to the New York State Diagnostic Laboratory over a 1-year period were tested for the presence of coronavirus antibodies, using the computer-assisted, kinetics-based enzyme-linked immunosorbent assay (KELA). Cats from which sera were obtained were categorized by sex, age, breed, and disease status, and variations in mean antibody titers for different sub-classifications within each category were analyzed by computerized statistical analysis. As expected, higher mean antibody titers were recorded for cats with feline infectious peritonitis, and for cats with a recent history of possible coronavirus exposure. However, an unexpected inverse relationship between coronavirus antibody titer and age was also found. Certain cattery-oriented pure breeds appeared to have higher mean antibody titers, because their sample populations contained a higher percentage of younger cats and cats of unknown age-groups which, over-all, had higher mean titers. Taken together, the data substantiated the efficacy of the computer-assisted KELA for routine detection of serum coronavirus antibodies in cats.  相似文献   
42.
Mycotic pneumonia in mariculture-reared green sea turtles   总被引:1,自引:0,他引:1  
Microbiologic examination of 29 juvenile green sea turtles with a buoyancy abnormality revealed pulmonary infection with Sporotrichium sp, Cladosporium sp, and Paecilomyces sp. Histologic examination of the lungs revealed granulomatous lesions containing branching septate hyphae. The diagnosis was mycotic pneumonia.  相似文献   
43.
The pharmacokinetics of diminazene aceturate following intramuscular (i.m.) administration at 4.2 mg/kg was evaluated in 8 healthy German Shepherd dogs. Blood samples were collected at 19 intervals over a period of 21 days. Diminazene plasma concentrations were measured using a validated HPLC method with UV detection and a sensitivity of 25 ng/ml. The in vitro and in vivo binding of diminazene to blood elements was additionally determined. Diminazene pharmacokinetics showed a large inter-individual variation after i.m. administration. It had a short absorption half-life (K01-HL of 0.11 +/- 0.18 h), resulting in a C(max) of 1849 +/- 268.7 ng/ml at T(max) of 0.37 h and a mean overall elimination half-life (T1/2beta) of 5.31 +/- 3.89 h. A terminal half-life of 27.5 +/- 25.0 h was measured. At 1 h after i.m. injection, 75% of the diminazene in whole blood was in the plasma fraction. The results of this study indicate that diminazene is rapidly distributed and sequestered into the liver, followed by a slower terminal phase during which diminazene is both redistributed to the peripheral tissues and/or renally excreted. It is recommended that diminazene administered i.m. at 4.2 mg/kg should not be repeated within a 21-day period.  相似文献   
44.
In control programs for Mycobacterium avium subsp. paratuberculosis (Map), the infection status of the cows in a herd is often obtained by testing (a sample of) the herd with an ELISA that may lack some sensitivity and specificity but that is fast and inexpensive. In New York State (NYS), an unabsorbed kinetics ELISA (KELA) has been used extensively for Map control. The objective of this study was to determine the relative sensitivity and specificity of the KELA for detection of fecal shedding of Map for the NYS dairy cow population, taking into account possible confounders such as different antigen batches and Map prevalence in a herd.

The data for the study consisted of all serum samples from NYS dairy cows with concurrent fecal culture results submitted to the NY Animal Health Diagnostic Laboratory (NYAHDL) between 1991 and 1996 (n = 10,562). The data represented cows with different levels of fecal shedding from herds with different within-herd Map prevalence, including herds that were whole herd fecal culture negative on repeated testing.

The cutoff values were based on the predictive value for fecal shedding obtained with a multiple logistic regression model that included variables for the three antigen batches and the Map prevalence in the herd. The KELA could not distinguish between non-shedders and low shedders (≤30 total colony forming units (TCFU)) and thus the predictive value of the KELA to detect moderate to heavy fecal shedders (>30 TCFU) was modeled. The three cutoff values of 65, 135 and 170 were based on low (<0.2), moderate (<0.80) and high (>0.95) probabilities for moderate to heavy fecal shedding. The sensitivity and specificity values relative to culture were 67% and 95.2%, 31% and 99.7%, and 11% and 99.9% for the three cutoff values, respectively. Cutoff values for the KELA decreased for herds with increasing within-herd Map prevalence. For the best positive predictive value of a KELA for moderate to heavy fecal shedding, the cutoff values should be determined based on the apparent within-herd prevalence in a herd.  相似文献   

45.
A sporozoan organism was considered to be the causative agent of central nervous system disease in a cockatiel. The ultrastructural characteristics were typical of the coccidian group Apicomplexa, and the fact that organisms were free within the cytoplasm of infected cells and not within a vacuole, indicated they were Sarcocystis. Light and electron microscopic evaluation of brain tissue demonstrated protozoal organisms associated with areas of necrosis. Differential diagnosis of central nervous system disease in pet birds should include protozoal encephalitis.  相似文献   
46.
We evaluated the effect of anticoagulant (lithium heparin, sodium heparin, or none) and type of autoanalyzer on selected blood biochemical values of the loggerhead sea turtle (Caretta caretta). More differences were observed between the analytes in serum and those in the 2 types of plasma than were observed between the 2 types of plasma. Differences in electrolyte concentrations were not significant when plasma from sodium-heparinized blood was compared with plasma from lithium-heparinized blood. Serum is not recommended for reptilian studies because clot formation is unpredictable and because the time required for clotting may allow substantial changes in the chemical composition of the sample. For most determinants, values varied more between the 2 types of autoanalyzers than among the 3 anticoagulant treatments. These sources of variation must be considered when performing comparative studies.  相似文献   
47.
48.
Cardiovascular effects of topical ophthalmic 10% phenylephrine in dogs   总被引:1,自引:1,他引:0  
Objective To evaluate the effect of topical ophthalmic 10% phenylephrine on systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), pulse rate (PR) and electrocardiogram (ECG) in dogs. Animals studied Nine clinically normal dogs. Procedure Arterial catheters were placed in the dorsal pedal artery of awake dogs and ECG leads were attached. After a 15‐min acclimatization period, baseline PR, SAP, DAP and MAP were recorded every 5 min for 20 min. Two treatment groups (eight dogs each) were studied. Group I: one drop of phenylephrine was placed in each eye once. Group II: one drop of phenylephrine was placed in each eye three times at 5‐min intervals. Following treatment, PR, SAP, DAP and MAP were recorded every 5 min for 90 min. The mixed procedure of the SAS system was used to perform a repeated measures analysis of variance to test for linear and quadratic trends across time. Results Group I: There was a significant quadratic decrease in PR across time (P = 0.0051). Systolic arterial pressure increased linearly with time (P = 0.0002), MAP increased linearly with time (P = 0.0131), and DAP increased linearly with time (P = 0.0001). Group II: There was a significant quadratic decrease in PR across time (P = 0.0023). There was a significant quadratic increase in SAP (P = 0.0324), MAP (P = 0.0103) and DAP (P = 0.0131) across time. Conclusions Topical ophthalmic application of 10% phenylephrine in normal dogs results in elevation of arterial blood pressure and reflex bradycardia.  相似文献   
49.
The genetic upper limit to daily whole-body protein deposition (Pdmax) is an important constraint on pig growth. The Pdmax was determined for a specified pig genotype using N balance and serial slaughter techniques. A traditional N-balance study, involving 36 and 90 kg of BW Large White x (Landrace x Large White) entire male pigs, was first conducted to demonstrate that a highly digestible, nutrient-dense diet (1.54% Lys; 18 MJ of DE/kg, air-dried basis) was able to support the attainment of Pdmax within the constraints of pig appetite. Animals were allocated to set levels of feed intake [set proportions of ad libitum DE intake (DEi), 50 to 100%]. Nitrogen retention increased linearly with DEi up to 25.3 and 35.2 MJ of DE/d for the 36 and 90 kg of BW pigs, respectively, then showed a departure (P < 0.05) from linearity. For DEi of the experimental diet above the latter intakes, which were approximately 80% of a determined ad libitum DEi, the pigs deposited protein at a rate approaching Pdmax. When a linear plateau response model (accepted a priori) was fitted, Pdmax values of 189.9 g/d at a DEi breakpoint of 28.3 MJ of DE/d at 36 kg of BW and 186.4 g/d at a DEi breakpoint of 37.3 MJ of DE/d at 90 kg of BW were found. In the serial slaughter study, 18 female and 18 entire male pigs were allocated to 5 slaughter BW (25, 45, 65, 85, and 110 kg) such that there were 5, 3, 3, 3, and 4 animals of each sex at each slaughter weight, respectively. Animals were fed the experimental diet ad libitum, and whole-body protein was determined at slaughter. Growth data were analyzed by differentiating and combining continuous mathematical functions for BW and body composition. The ad libitum DEi were 27.4 and 50.7 MJ/d at 36 and 90 kg of BW for the entire males and were assumed, based on the N-balance results, sufficiently high to allow expression of Pdmax. There was an effect (P < 0.05) of sex on Pdmax vs. time (days on trial). Over the BW range of 25 to 85 kg, Pdmax was constant for the entire male and female pigs at 170 and 147 g/d, respectively. Above 85 kg of BW, Pdmax was no longer constant for either sex.  相似文献   
50.
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