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101.

Background

Rapid determination of blood electrolyte concentrations can help determine electrolyte status and delivery of effective volume of electrolyte solutions in field conditions.

Objective

To evaluate reliability of the i‐STAT, a point‐of‐care (POC) device, in measuring blood K+, Na+, and CI concentrations in cattle.

Animals

Ninety‐eight cattle with various diseases.

Methods

In this prospective study, blood samples collected from the jugular vein were processed for determination of K+, Na+, and CI concentrations in blood and plasma using the i‐STAT and auto‐analyzer (Cobas C501), respectively. Blood and plasma electrolyte data were subjected to student t‐test for comparison, the concordance analysis for agreement, accuracy, and precision, the Passing‐Bablok regression and the Bland‐Altman plot for reliability, and receiver operating characteristics curves for sensitivity (Se) and specificity (Sp).

Results

Plasma concentrations of K+ (4.39 versus 4.2 mmol/L; < .0001) and CI (100.30 versus 99.4 mmol/L; < .04) were greater than their concentrations in blood. Plasma and blood Na+ concentrations were similar (136.95 versus 136.8 mmol/L). The i‐STAT results were highly correlated with the Cobas C501 results (= 0.970, 0.922, and 0.866 for K+, Na+, and CI , respectively). Regression equations fitting blood (Y) and plasma (X) concentration did not deviate from the identity line for K+ (Y = −0.10 + 0.98 × X), Na+ (Y = X), and CI (Y = 3.04 + 0.96 × X). The mean bias (blood concentration ‐ plasma concentration) was −0.20 for K+ (= .03), −0.16 for Na+ (= .12), and −0.87 for CI (= .93). The i‐STAT had 76–100% Se and 87.7–100% Sp for assessing electrolyte statuses.

Conclusions and Clinical Importance

The i‐STAT yielded results that were in agreement with the auto‐analyzer, with negligible biases in measurement of plasma K+, Na+, and CI concentrations. The i‐STAT is a reliable POC device and can be used in field condition to assess electrolyte status in cattle.  相似文献   
102.
In order to study the effect of brassinosteroids on the amelioration of the inhibitory effect of salinity on strawberry plants, a short-term experiment was conducted in greenhouse to test different concentrations of 24-epibrassinolide (24-EBL) (0.0, 0.5, and 1 μM) by foliar application on some agro-physiological properties, such as shoot dry weight, and root dry weight, stomatal conductance (SC), leaf relative water content (LRWC), leaf chlorophyll reading values (LCRV) and membrane permeability (MP) of strawberry ‘Fern’ and ‘A6’ cultivars irrigated with salt water (35 mM NaCl). 24-EBL solutions were applied twice during late afternoon hours with 7 d intervals using a hand-held sprayer. Plant shoot dry weight, root dry weight, SC, LRWC and LCRV were reduced by 29–33%, 45–15%, 71–55%, 11–13%, and 12–13% for ‘A6’ and ‘Fern’ cultivars at 35 mM (without 24-EBL applied), respectively, as compared to the nonsaline treatment, but MP increased 40% and 12%. An exogenous supply of 24-EBL was found to be successful in alleviating of the inhibitory effects of salt stress on plant growth parameters and nutrient contents. 24-EBL (1 μM) application under saline condition significantly increased shoot and root dry matter, SC, LRWC and LCRV of plants, and alleviation effects of 1 μM 24-EBL application was 20%, 15%, 122%, 5.8%, and 10.9% for ‘A6’ and 47%, 8.0%, 83%, 33.3% and 6.0% for ‘Fern’ cultivars, respectively. Macro-micro element content of plant leaf and root increased with increase 24-EBL except for Na under salinity stress. These results support the view that supplementary 24-EBL application can overcome the effects of salinity stress on plant growth and growth parameter under saline conditions.  相似文献   
103.
104.
This study aimed to determine the plasma disposition and faecal excretion of netobimin (NTB) and its respective metabolites as well as the efficacy against strongyles in horses following oral administration. Netobimin (10 mg/kg) was administered orally to 8 horses. Blood and faecal samples were collected from 1 to 120 h post-treatment and analysed by high performance liquid chromatography (HPLC). Using a chiral phase-based HPLC, plasma disposition of ABZSO enantiomers produced was also determined. Faecal strongyle egg counts (EPG) were performed by a modified McMaster’s technique before and after the treatment. Neither NTB nor ABZ were present and only albendazole sulphoxide (ABZSO) and sulphone metabolites (ABZSO2) were detected in the plasma samples. Maximum plasma concentration of ABZSO (0.53 ± 0.14 μg/ml) and ABZSO2 (0.36 ± 0.09 μg/ml) were observed at (tmax) 10.50 and 19.50 h, respectively following administration of NTB. The area under the curve (AUC) of the two metabolites was similar to each other. Netobimin was not detected, and ABZ was predominant in faecal samples. The maximum plasma concentration (Cmax) of (−)ABZSO was significantly higher than (+)ABZSO, but the area under the curves (AUCs) of the enantiomer were not significantly different each other in plasma samples. The enantiomers of ABZSO were close to racemate in the faecal samples analyzed. Netobimin reduced the EPG by 100%, 100%, 77%, 80% and 75% 2, 4, 6, 8 and 10 weeks post-treatment, respectively. The specific behaviour of the two enantiomers probably reflects different enantioselectivity of the enzymatic systems of the liver which are responsible for sulphoxidation and sulphonation of ABZ. Considering the pharmacokinetic and efficacy parameters NTB could be used as an anthelmintic in horses.  相似文献   
105.
This study was conducted to evaluate the roles of glycine betaine (GB) in mitigating deleterious effect of salt stress on lettuce. Lettuce plants were subjected to two salinity (0 and 100 mmol l?1 NaCl) and four GB levels (0, 5, 10, 25 mmol l?1). Salinity resulted in a remarkable decrease in growth parameters, relative leaf water content and stomatal conductance. Plants subjected to salt stress exhibited an increase in membrane permeability (MP), lipid peroxidation (MDA), leaf chlorophyll reading value, H2O2 and sugar content. Exogenous foliar applications of GB reduced MP, MDA and H2O2 content in salt-stressed lettuce plants. Salt stress increased Na and generally decreased other nutrient elements. GB reduced Na accumulation, but significantly increased other element contents under salinity conditions. The study showed that gibberellic acid (GA) and salicylic acid (SA) content in salt-stressed plants were lower than those of nonstressed plants. However, salinity conditions generally increased the abscisic acid content. GB treatments elevated the concentrations of GA, SA and indole acetic acid (IAA) at especially 10 and 25 mmol l?1 GB under salt stress conditions. It could be concluded that exogenous GB applications could ameliorate the harmful effects of salt stress in lettuce.  相似文献   
106.
107.
Variation in the immune status of two Australian pig breeds   总被引:1,自引:0,他引:1  
Objective To investigate the variation in immune competence of two Australian pig breeds.
Design A panel of immune tests were used to assess breed and sire differences in weaner piglets of Large White and Duroc breeds.
Procedure All piglets were immunised against porcine leptospirosis. Blood samples were taken for studies on lymphocyte phenotypes, mitogenic responses of blood cells and serological analysis.
Results Significantly larger blood leucocyte numbers were found in Large White piglets compared with Duroc piglets after vaccinations. No significant difference in concanavalin A induced blood cell proliferation was found between these two breeds before or after vaccinations. Some significant breed variation in blood lymphocyte phenotypes was found. While the age-related changes of lymphocyte phenotypes were similar for the two breeds, the Large White breed had significantly larger numbers of CD2+ and CD4+ cells than the Duroc breed after the two vaccinations. There were also significant sire effects on CD8+ cells within the Large White breed after the first vaccination. No significant breed difference was detectable in serum IgG concentrations but sire differences within each breed before the primary vaccination were found. The serum antibody response to vaccination against leptospirosis was generally small, and showed no variations due to either breed or sire. No gender effects were found during the entire study.
Conclusion The study demonstrated significant differences in some important immune components of the pig breeds studied. This may in turn indicate the variation in their immune competence or disease resistance. However, further investigation into the heritability and correlation with specific immune responses is required.  相似文献   
108.
Flocks of broiler breeder chickens housed on a commercial farm were monitored from 13 w of age for natural infection with endemic lentogenic Newcastle disease virus (NDV). Seroconversion was first detected at 17 w. By 24 w, all 8 flocks had achieved peak log2 mean haemagglutination inhibiting antibody titres of up to 4.8. Antibody titres then declined and rose again over several months, suggesting cyclic reinfection with NDV. A lentogenic NDV indistinguishable from V4 was isolated from the cloaca of one bird at 18 weeks of age. At 54 weeks of age, 6 of 8 flocks were vaccinated en masse with live V4 NDV vaccine, 3 flocks by drinking water and 3 flocks by aerosol. All flocks were serologically monitored for a further 8 w. Drinking water vaccination induced an anamnestic response in 3 flocks, showing that flocks with pre-existing active immunity to NDV may be successfully vaccinated with V4. However, in all aerosol vaccinated flocks, the procedures failed to induce a response different to that observed in unvaccinated flocks. The serological response to vaccination was greater in sires than in dams.  相似文献   
109.
The present study was performed to investigate streptococci of serological group B obtained from various sources and group B streptococcal reference strains for serotype, hyaluronate lyase enzyme activity, the occurrence of the hylB gene and the insertion sequence IS1548. All group B streptococci were identified by cultural, biochemical, and serological properties and by polymerase chain reaction amplification of species-specific parts of the 16S-23S rDNA intergenic spacer region, the 16S rRNA gene and the CAMP-factor (cfb) gene. Of the 73 group B streptococci investigated, 59 strains displayed hyaluronate lyase enzyme activity. All hyaluronate-lyase-positive strains and three phenotypically hyaluronate-lyase-negative strains had a hylB gene with an amplicon size of 3.3kb. Eleven of the 14 phenotypically hyaluronate-lyase-negative strains generated a hylB gene PCR product with a size of 4.6kb, and 10 of these strains displayed a IS1548 amplicon with a size of 0.98kb. The hyaluronate-lyase-negative isolates were mainly observed among group B streptococci of serotype III/Rib. All strains harbouring IS1548 had an additional copy of IS1548 located downstream of the C5a peptidase (scpB) gene.  相似文献   
110.
Meat chickens on commercial broiler farms were vaccinated once at 1 to 15 days of age with a live V4 Newcastle disease virus (NDV) vaccine administered by drinking water, aerosol or coarse spray. Hatchmates were housed and similarly vaccinated in laboratory isolation pens. Samples of birds were bled at weekly to fortnightly intervals and the serums tested for haemagglutination inhibiting antibody to NDV. Log2 mean titres of up to 6.26, and assumed protection levels (based on the percentage of birds with log2 titres of 4 or greater) of up to 89%, were obtained in field trials within 4 weeks of vaccination. Differences were observed between the results obtained from parallel field and laboratory trials. The presence of maternal NDV antibody reduced the response to vaccination. The results show that this V4 vaccine can produce an adequate serological response following mass administration to Australian meat chickens housed under commercial conditions.  相似文献   
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