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101.
Some studies have shown that relative to baseline, the renal resistive index (RI) remains unchanged in nonobstructed kidneys and increases in obstructed kidneys after administration of furosemide. To our knowledge, the effect of mannitol administration on the renal RI of dogs has not been reported. We evaluated the renal RI in 16 kidneys in 8 young adult dogs after administration of mannitol. The mean RI decreased significantly from baseline (P < .01). Additionally, left complete ureteral obstruction wasinduced in 5 dogs. Evaluation by Doppler ultrasonography was performed for 5 days. On the 5th day, Doppler examination was repeated at 30 and 60 minutes after administration of mannitol to obstructed dogs. After induction of left ureteral obstruction, the RI of the left kidney increased significantly over 5 consecutive days. Administration of mannitol decreased the RI in the nonobstructed contralateral kidneys, and thus the RI difference between obstructed and nonobstructed kidneys was increased above normal (P < .001). In conclusion, administration of mannitol may be useful as another diuretic agent to identify unilateral ureteral obstruction on Doppler sonographic examination.  相似文献   
102.
Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition followed three-compartment open model. The values of Vdarea, AUC, t1/2β, ClB, MRT and P/C ratio were 0.50 ± 0.19 L.kg−1, 62.2 ± 23.3 μg.ml−1.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg−1.h−1, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg−1, 37.0 ± 17.1 μg.ml−1.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg−1.h−1, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration. For MIC90 of 0.5 μg.ml−1 the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg−1 repeated at 6 h intervals for the treatment of endometritis in cows.  相似文献   
103.
Data collected by the National Livestock Research Institute of the Rural Development Administration of Korea were used to estimate genetic parameters for yearling (YWT, n = 5,848), 18-mo (W18, n = 4,585), and slaughter (SWT, n = 2,279) weights for Korean Native cattle. Nine animal models were used to obtain REML estimates of genetic parameters: DP-2 included genetic, uncorrelated dam, and residual random effects; DQ-2 included genetic, sire x region x year-season interaction, and residual random effects; DPQ-2 was based on DQ-2 but included both interaction and dam effects; DMP-2 was based on DP-2 but with dam effect partitioned to include maternal genetic and permanent environmental effects; and DMPQ-2 was based on DMP-2 but also included sire interaction effects. Those five models included two fixed factors: region x year-season and age of dam x sex effects. Models DP-3, DQ-3, DPQ-3, and DMPQ-3 were based on DP-2, DQ-2, DPQ-2, and DMPQ-2 but included as a third fixed factor whether or not identification of the sire was known. Estimates of heritability with DMPQ-3 for YWT, with DPQ-3 for W18 and SWT when analyzed with single-trait analyses were .14, .11, and .17, respectively, and were nearly the same with bivariate analyses. Estimate of maternal heritability for YWT from single-trait analysis was .04, with estimates for other traits near zero. For bivariate analyses, the estimate for YWT was .01. With single trait analysis, estimate of the direct-maternal genetic correlation for YWT was negative (-.81). Estimates of direct genetic correlations between YWT and W18, YWT and SWT, and W18 and SWT were .99, 1.00, and .97, respectively. Estimates of environmental correlations varied from .60 to .81; the largest was between W18 and SWT. Including a fixed factor for whether sire identification was missing or not missing reduced the estimate of heritability for slaughter weight. The results suggest that the sire x region x year-season interaction is important for yearling weight and may be needed in a model for slaughter weight. Maternal effects may be of slight importance for yearling weight but of no importance for W18 and SWT. Models for national cattle evaluations for Korean Native cattle for YWT should be considered that include maternal genetic and permanent environmental as well as sire x region x year-season interaction effects, but those effects seem not to be needed for models for W18 and SWT. Not much reranking of sires occurred when ranked was based on the different models for W18 and SWT.  相似文献   
104.
Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.  相似文献   
105.
Q fever (QF) is a worldwide zoonosis associated with outbreaks. Only a few nationwide studies regarding the surveillance and epidemiology of human QF have been reported. Although QF is endemic in Taiwan, a nationwide database investigation of the epidemiology and characteristics of QF and its associations with scrub typhus (ST), murine typhus (MT) and leptospirosis (LS) has never been reported. We analysed nationwide databases of suspected QF, ST, MT and LS cases from October 2007 to December 2014 obtained from the Centers for Disease Control, Taiwan. A total of 468 (4.2%) QF cases were identified among 11 109 suspected QF cases. QF cases were mainly distributed in the southern and Kaohsiung–Pingtung regions but rarely in the eastern region. Compared to non‐QF cases, QF cases had significantly higher percentages of males (88.7 versus 66.2%) and high‐risk occupations (farming, animal husbandry or veterinary medicine) (16.2 versus 10.5%). But the percentages of specific animal contact, including cattle (0.6 versus 0.8%) and goats (0.9 versus 1.0%), were low in both. The majority of suspected QF cases (89.4%) were simultaneously suspected with ST, MT or LS, and the combinations of suspected diseases differed between regions. The number of suspected QF cases from the eastern region decreased since 2009, which was not observed in other regions. A total of 1420 (12.8%) cases had confirmed diseases, including QF (453, 4.1%), QF+ST (7, 0.06%), QF+MT (4, 0.04%), QF+LS (4, 0.04%), MT (186, 1.7%), ST (545, 4.9%), ST+LS (11, 0.1%) and LS (210, 1.9%). Compared to cases of unknown disease, QF cases had larger percentages of high‐risk occupations (16.2 versus 9.6%) but similar histories of animal contact (29.8 versus 25.1%). QF is an endemic disease in southern Taiwan. It is difficult to differentiate QF from ST, MT or LS only by high‐risk occupations and history of animal contact, and co‐infection of QF with these diseases should be considered.  相似文献   
106.
107.
108.
Livestock production is an integral part of the rain-fed and irrigated agriculture system in Pakistan. Animal production is closely interlinked with the cropping systems and play a crucial role in the rural economy. Participatory rural appraisals and economic opportunity surveys were conducted in two ecological zones (irrigated and rain-fed) and two dairy production systems (peri-urban and mixed livestock). Major constraints in animal health, nutrition and reproduction were identified and interventions were suggested to overcome these difficulties. The economic opportunity survey revealed that maximum opportunity to enhance farmers’ income is to increase milk production per day per animal, which can be accomplished through coordinated improvements in nutrition, reproduction and genetics.  相似文献   
109.
The objective of this study was to determine relationship of gestational age with measurement of diameter of head, orbit, trunk, long and short axis of heart, aorta, placentome, umbilical cord and umbilical vein in Korean black goats. In this study, ten pregnant Korean black goats (Capra hircus aegagrus) were used. Pregnancy diagnosis was performed with a 5 MHz linear transducer and ultrasonographic scan were performed at 60, 75, 90, 105, 120 and 135 days after mating with a 4-9 MHz convex transducer. For accurate measurement, all fetal organs were measured at least 3 times. The diameter of head, orbit, trunk, long and short axis of heart, aorta, placentome, umbilical cord and umbilical vein were significantly increased with the gestational age (p<0.05). Of these parameters, trunk (r=0.8876; p<0.001), long axis of heart (r=0.9168; p<0.001) and short axis of heart (r=0.8819; p<0.001) proved to be the more effective measurements than other parameters, as it correlated well with gestational age. Results indicate that ultrasonic measurements of these parameters were useful methods to estimate gestational age in Korean black goat.  相似文献   
110.
This study was carried out to investigate the changes of orexin-A (OXA) and neuropeptide Y (NPY) expression in the hypothalamus of the obese and lean Zucker Diabetic Fatty (ZDF) rats which have a missense mutation in the leptin receptor gene. The mean body weights (MBW) between the obese and lean ZDF rats were significantly different at 28 and 70 postnatal days. However, at 14 postnatal day, there was no significant difference in the MBW between the obese and lean ZDF rats in both male and female. The OXA immunoreactivities were not significantly different between the obese and lean ZDF rats in both sexes at 14, 28, and 70 postnatal days, respectively. The NPY immunoreactivity was higher in the obese than in the lean ZDF rats in both male and female at 28 and 70 postnatal days, whereas there was no significant difference between the obese and lean ZDF rats at 14 postnatal day. These results indicate that both OXA and NPY might halt their roles for food intake in the obese phenotype of the male and female ZDF rats in the preweaning period of 14 postnatal day, whereas NPY might play a main role in the obesity of these rats in the weaning period of 28 and 70 postnatal days.  相似文献   
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