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41.
ObjectiveTo compare the cardiorespiratory, anesthetic-sparing effects and quality of anesthetic recovery after epidural and constant rate intravenous (IV) infusion of dexmedetomidine (DEX) in cats given a low dose of epidural lidocaine under propofol-isoflurane anesthesia and submitted to elective ovariohysterectomy.Study designRandomized, blinded clinical trial.AnimalsTwenty-one adult female cats (mean body weight: 3.1 ± 0.4 kg).MethodsCats received DEX (4 μg kg?1, IM). Fifteen minutes later, anesthesia was induced with propofol and maintained with isoflurane. Cats were divided into three groups. In GI cats received epidural lidocaine (1 mg kg?1, n = 7), in GII cats were given epidural lidocaine (1 mg kg?1) + DEX (4 μg kg?1, n = 7), and in GIII cats were given epidural lidocaine (1 mg kg?1) + IV constant rate infusion (CRI) of DEX (0.25 μg kg?1 minute?1, n = 7). Variables evaluated included heart rate (HR), respiratory rate (fR), systemic arterial pressures, rectal temperature (RT), end-tidal CO2, end-tidal isoflurane concentration (e′ISO), arterial blood gases, and muscle tone. Anesthetic recovery was compared among groups by evaluation of times to recovery, HR, fR, RT, and degree of analgesia. A paired t-test was used to evaluate pre-medication variables and blood gases within groups. anova was used to compare parametric data, whereas Friedman test was used to compare muscle relaxation.ResultsEpidural and CRI of DEX reduced HR during anesthesia maintenance. Mean ± SD e′ISO ranged from 0.86 ± 0.28% to 1.91 ± 0.63% in GI, from 0.70 ± 0.12% to 0.97 ± 0.20% in GII, and from 0.69 ± 0.12% to 1.17 ± 0.25% in GIII. Cats in GII and GIII had longer recovery periods than in GI.Conclusions and clinical relevanceEpidural and CRI of DEX significantly decreased isoflurane consumption and resulted in recovery of better quality and longer duration, despite bradycardia, without changes in systemic blood pressure.  相似文献   
42.
1. The objective of this study was to examine whether the energy availabilities of two wheat samples, which differed in endosperm hardness, were changed when they were fed ground or as whole grains to chickens. Wheat samples of a variety Haven (hard endosperm) and a variety Riband (soft endosperm), both harvested in 1993 from the same growing site, were used in the experiment.

2. True metabolisable energy (TMEn) was measured in a flock of 24 adult cockerels and the mean of all the samples was 14.68 MJ/kg dry matter (DM). The TMEn of ground wheat was 0.306 MJ/kg DM greater (P< 0.05) than whole grain. There was no significant difference (P> 0.05) in TMEn between the Riband and Haven wheat samples and there were no (P> 0.05) variety X wheat form interactions.

3. The apparent metabolisable energy (AMEn) of the wheat samples was determined with 96 broiler chickens from 19 to 27 d of age. Different amounts of either whole or ground wheat samples were added to a basal diet. Extrapolation of the regression lines indicated AMEn concentrations (MJ/kg DM) of ground Haven 14.33, whole Haven 14.28, ground Riband 14.33 and whole Riband 14.51. There was no evidence (P> 0.05) that whole grain wheat had a different AMEn than ground wheat.

4. A feeding trial used 192 broiler chickens in 48 cages from 24 to 42 d of age. They were fed on a broiler grower diet either mixed with ground wheat before pelleting or with the pelleted grower diet loosely mixed with the whole wheat. There were no differences (P> 0.05) between the 2 wheat varieties or the diet form in growth rates or food conversion ratios. The growth rates of the broilers given a conventional grower and finisher dietary regimen tended (P> 0.05) to be slightly greater than the broilers given the wheat‐diluted diets.  相似文献   

43.
OBJECTIVES: To evaluate the effects of a combination of tiletamine-zolazepam-romifidine-atropine in ocelots. DESIGN: Prospective experimental trial. ANIMALS: Eight captive adult ocelots (three females and five males). METHODS: Calculated doses of tiletamine-zolazepam (3.75 mg kg(-1)), romifidine (50 microg kg(-1)) and atropine (0.04 mg kg(-1)) were administered intramuscularly. After immobilization, animals were weighed and the real doses determined. Heart rate, respiratory frequency, noninvasive systolic, diastolic, and mean arterial pressure, arterial oxygen hemoglobin saturation, and rectal temperature were measured. Data were analyzed by means of anova for repeated measures, followed by the Tukey test to compare values over time. RESULTS: Doses administered were 3.4 +/- 0.6 mg kg(-1) of tiletamine-zolazepam, 0.04 +/- 7.0 mg kg(-1) of romifidine, and 0.03 +/- 0.007 mg kg(-1) of atropine. The mean time to recumbency and duration of immobilization were 7.0 +/- 4.5 and 109.2 +/- 27.9 minutes, respectively. The median times to standing and walking were 52.3 [0-90] and 2.3 [0-69.3] minutes, respectively. A decrease in heart rate was observed 45 minutes following drug administration. Arterial blood pressure was maintained during the study. CONCLUSIONS AND CLINICAL RELEVANCE: This protocol produced good immobilization in ocelots with minimal changes over time in cardiovascular parameters.  相似文献   
44.
A total of 714 samples consisting of faeces, mesenteric lymph nodes, liver, spleen, abdominal and diaphragmatic muscles (each 119) were collected from November 2001 to April 2002 from apparently healthy slaughtered camels (Camelus dromedarius) in eastern Ethiopia. One hundred sixteen (16.2%) Salmonella strains belonging to 16 different serovars were isolated. All Salmonella strains isolated were examined for antimicrobial resistance to 17 selected antimicrobials. The minimum inhibitory concentration (MIC) values were determined by the microdilution broth test. Fifty-two (44.8%) of the Salmonella isolates were resistant to one or more antimicrobials. Thirty-nine of the 52 (75%) resistant Salmonella serovars exhibited multiple resistance to up to eight different antimicrobials. Among the serovars tested, S. Typhimurium, S. Heidelberg, S. Braenderup and S. Hadar displayed multiple resistance mainly to streptomycin (35.3%), spectinomycin (28.4%), sulfamethoxazole (25.0%), ampicillin (24.1%), trimethoprim (22.4%), trimethoprim/sulfamethoxazole (18.9%), tetracycline (12.9%) and colistin (11.2%). All Salmonella strains tested were susceptible to ciprofloxacin, nalidixic acid, gentamicin, kanamycin and neomycin. The present study showed the importance of camels as a potential source of single and multiple resistant Salmonella strains to different antimicrobials that are also used in the public health sector for the treatment of different bacterial diseases in Ethiopia.  相似文献   
45.
The cardiovascular, respiratory, and anesthetic effects of medetomidine-ketamine (20 microg/kg bodyweight [BW] and 10 mg/kg BW) (MK group) or dexmedetomidine-ketamine (10 microg/kg BW and 10 mg/kg BW) (DK group) were studied in golden-headed lion tamarins. Heart rate decreased after administration of both combinations; this reduction was statistically greater in the DK group than in the MK group after 15 and 45 minutes. Systolic arterial pressure decreased in a similar way in both groups, except at 15 minutes, when systolic arterial pressure was significantly lower in the DK group. Diastolic arterial pressure, mean arterial pressure, respiratory rate, and rectal temperature were progressively reduced in all groups. Sedation time was significantly shorter and anesthesia time was significantly longer in the DK group compared with MK group. Anesthetic quality and analgesia scores were significantly greater at 5 and 15 minutes in the DK group compared with the MK group. The administration of dexmedetomidine-ketamine is as safe and effective as the administration of medetomidine-ketamine in tamarins.  相似文献   
46.
Epidermal growth factor (EGF) and glucagon‐like peptides (GLP) modulate the tight junctions (TJ) of the intestinal epithelial barrier (EB) of monogastric animals. This work tried to elucidate whether GLP‐1, GLP‐2 and EGF can affect the EB of the rumen. Ovine ruminal epithelia were incubated in Ussing chambers for 7 hr with 25 or 250 nM of either GLP‐1 or GLP‐2 on the serosal side, with 2.5 nM of EGF on the serosal side or with 0.25 or 2.5 nM EGF on the mucosal side. No treatment affected tissue conductance. Short‐circuit current (Isc) was affected by time and treatment and their interactions. Only 250 nM of either GLP‐1 or GLP‐2 decreased Isc in certain periods compared with 25 nM GLP‐1 or 0.25 nM mucosally applied EGF; however, not when compared to control epithelia. Fluorescein flux rates (Jfluor) of ruminal epithelia were affected by treatment, time and time × treatment interaction. The time × treatment interaction was based on an increase in Jfluor between the first and last hour in epithelia incubated with 25 nM GLP‐1 or GLP‐2 and in epithelia incubated with EGF. After 7 hr incubation, claudin‐7 mRNA expression was downregulated in all treatments. Claudin‐1 mRNA was upregulated after incubation with 2.5 nM EGF on the serosal side, claudin‐4 mRNA was downregulated by 2.5 nM EGF on the mucosal side, and occludin mRNA was increased after incubation with 250 nM GLP‐2. The protein abundance of all tested TJ proteins was not influenced by treatment. We conclude that GLP‐1, GLP‐2, and EGF have no obvious acute effects on the EB of ruminal epithelia under simulated physiological conditions ex vivo. However, by decreasing the mRNA expression of claudin‐7 and partly affecting other TJ proteins, they may modulate EB in the longer term or under certain conditions.  相似文献   
47.
Bird migration has long been hypothesized as the main mechanism for long‐distance dispersal of flaviviruses, but the role of migratory birds in flaviviruses spillover is not well documented. In this study, we investigated the eco‐epidemiology of West Nile virus (WNV) and Usutu virus (USUV) in trans‐Saharan passerines during their spring stopover in southern Tunisian oases. To do, we combined oral swab analysis and serological tools to assess whether migratory birds could be reaching these stopover sites while infectious or have been previously exposed to viruses. All sampled birds tested negative for oral swab analysis. However, anti‐WNV and anti‐USUV antibodies were detected in 32% and 1% of tested birds, respectively. Among WNV‐seropositive species, the Golden oriole (Oriolus oriolus) showed the highest anti‐WNV occurrence probability. In this species, anti‐WNV occurrence was twice larger in males than females. Inter‐specific and intraspecific morphological, physiological and behavioural differences could explain these results. Although our findings did not show evidence for passerines migrating while infectious, they did not exclude an existing enzootic WNV transmission cycle in Tunisian oases. Further investigations including larger samples of migratory birds are needed for a better understanding of this issue.  相似文献   
48.
The date palm, Phoenix dactylifera, is a palm extensively cultivated for its edible fruit. The chemical composition and the water content of ten Tunisian date varieties were determined. For all analysis, the Deglet Nour variety was taken as reference. Compositional analysis showed that the littoral varieties were very rich in reducing sugars (26 to 51%) than Deglet Nour which was rich in sucrose (54%). The relative results of the moisture content showed that the littoral varieties were classified as soft dates. The vitamin C analysis showed that the littoral varieties were very rich in this compound (24 to 46 mg/100 g) than Deglet Nour (1.12 mg/100 g). The mineral analysis showed that the littoral dates were relatively rich in potassium (283 to 733 mg/100 g) and presented a weak content in sodium (0.06 to 0.09 mg/100 g).  相似文献   
49.
The leaf extract and its fractions of Peganum harmala L. have shown pronounced mortal effect, decreased percent pupation and adult emergence of the cotton leaf worm, Spodoptera littoralis Boisd. The third instar larvae fed for two days on treated leaves were more susceptible to plant extract and its ethyl acetate and chloroform fractions. The active lowest concentration (5%) of the leaf fractions of P. harmala showed significant effect on the percentage of emerged adult parasitoids, Microplitis rufiventris Kok. GC/MS analysis showed the major constituent in ethyl acetate fraction was (23S) ethylcholest-5-en-3 beta-ol (28.04%) while those of chloroform fraction were hydroxyfuranocoumarin (Bergaptol) (15.68%), piperidinone (12.08%), thymol (11.82%), phosphoric acid, tributyl ester (9.80%) and trimethyl-nonenol (9.66%). The medicinal plant P. harmala could be carefully applied in integrated pest management due to its strong effect on cotton leaf worm pest.  相似文献   
50.
Wheat straw burial has great potential to sustain rice production under alternate wetting and drying (AWD) irrigation. A field experiment was conducted with three wheat straw burial treatments, including without straw burial (NSB), with light straw burial of 300 kg/hm2 (LSB) and dense straw burial of 800 kg/hm2 (DSB), as well as three AWD regimes: alternate wetting/moderate drying (AWMD), alternate wetting/severe drying (AWSD) and alternate wetting/critical drying (AWCD). The rice growth and grain quality were higher in LSB and NSB than those in NSB under the same AWD regime. The AWMD × DSB treatment resulted in the highest yield, brown rice rate, milled rice rate, amylose content and protein content. Conversely, the AWCD × NSB treatment led to the lowest yield, brown rice rate, milled rice rate, amylose content and protein content. The active absorption area and nitrate reductase activity of roots were higher in the AWMD × DSB treatment than those in the AWCD × NSB treatment, as the former increased organic carbon and nitrogen contents in the rhizosphere, whereas the latter reduced their availability. Total soluble protein content and glutamine synthetase activity were greater in the AWMD × DSB treatment than those in the AWCD × NSB treatment. The activities of superoxide dismutase and catalase were higher in the AWMD × DSB treatment compared with the AWCD × NSB treatment, leading to the amelioration of oxidative cell injury, as shown by a lower malonaldehyde level. This study suggested that farmers should implement AWMD irrigation after leaving the straw residues in the field, followed by deep tillage to improve soil quality and mitigate the drought stress cycles of AWD. This approach can improve rice growth and grain quality and alleviate the problems of disposal of straw residues and water scarcity for sustainable rice production.  相似文献   
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