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71.
A radiographic technique was used to identify and characterize segmental diaphragmatic movement in anesthetized ponies breathing spontaneously and with controlled ventilation with and without muscle relaxant-induced paralysis. Paralyzed mechanically ventilated ponies were also studied at varying peak inspiratory pressures. Controlled ventilation induced a change in pattern of diaphragmatic displacement which was accentuated by paralysis and increased inspiratory pressure. In conclusion, these results indicate that uneven distribution of inspired gases is not corrected by mechanical ventilation. Furthermore, increased tidal volume during mechanical ventilation is largely wasted because this increased volume is distributed principally to the poorly perfused nondependent lung. Thus, while mechanical ventilation can alleviate hypoventilation, i.e., will decrease PaCO2, it will be of limited value in relieving arterial hypoxemia due to venous admixture in anesthetized patients.  相似文献   
72.
This is the first of a series of capsule reviews published by the World Small Animal Veterinary Association ‐ Global Pain Council (WSAVA‐GPC). Each of these short articles provides a brisk assessment of the scientific evidence in specific aspects of pain management, including analgesic techniques, recommendations and controversies surrounding their use. In this first capsule review, the scientific evidence available on the long‐term use of non‐steroidal anti‐inflammatory drugs in cats with concomitant chronic pain and chronic kidney disease is discussed.  相似文献   
73.
74.
Kumar, V., Madabushi, R., Lucchesi, M. B. B., Derendorf, H. Pharmacokinetics of cefpodoxime in plasma and subcutaneous fluid following oral administration of cefpodoxime proxetil in male beagle dogs. J. vet. Pharmacol. Therap. 34 , 130–135. Pharmacokinetics of cefpodoxime in plasma (total concentration) and subcutaneous fluid (free concentration using microdialysis) was investigated in dogs following single oral administration of prodrug cefpodoxime proxetil (equivalent to 5 and 10 mg/kg of cefpodoxime). In a cross over study design, six dogs per dose were utilized after a 1 week washout period. Plasma, microdialysate, and urine samples were collected upto 24 h and analyzed using high performance liquid chromatography. The average maximum concentration (Cmax) of cefpodoxime in plasma was 13.66 (±6.30) and 27.14 (±4.56) μg/mL with elimination half‐life (t1/2) of 3.01 (±0.49) and 4.72 (±1.46) h following 5 and 10 mg/kg dose, respectively. The respective average area under the curve (AUC0–∞) was 82.94 (±30.17) and 107.71 (±30.79) μg·h/mL. Cefpodoxime was readily distributed to skin and average free Cmax in subcutaneous fluid was 1.70 (±0.55) and 3.06 (±0.93) μg/mL at the two doses. Urinary excretion (unchanged cefpodoxime) was the major elimination route. Comparison of subcutaneous fluid concentrations using pharmacokinetic/pharmacodynamic indices of fT>MIC indicated that at 10 mg/kg dose; cefpodoxime would yield good therapeutic outcome in skin infections for bacteria with MIC50 upto 0.5 μg/mL while higher doses (or more frequent dosing) may be needed for bacteria with higher MICs. High urine concentrations suggested cefpodoxime use for urinary infections in dogs.  相似文献   
75.
Determination and kinetics of enrofloxacin and ciprofloxacin in Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a liquid chromatography/mass spectrometry method. J. vet. Pharmacol. Therap. 34, 142-152. The fluoroquinolones enrofloxacin (EF) and ciprofloxacin (CF) residues were investigated in the edible tissues of two important Asian aquacultured species such as Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry method. Fish and prawn were treated with medicated feed with multiple doses of EF, in field conditions. A validation study of the analytical method was realized in terms of linearity, specificity, precision (repeatability and within-laboratory reproducibility), recovery and decision limit (CCα). The time needed before the antibiotic disappears from animal tissues or reach the maximum residue limit (MRL, 100μg/kg) was assessed. The concentration values of EF detected in Tra catfish tissue were between the MRL and 2×MRL concentrations, according to the fish density, 7days following the end of the enrofloxacin treatment (20mg/kg body weight per day, for seven consecutive days). The concentration value of ER in prawn tissue was lower than the MRL and the limit of quantification (LOQ, 14μg/kg) 5 and 7days after the stop of the EF treatment (50mg/kg body weight per day, for five consecutive days), respectively. The mean detected levels of CF was much lower in comparison with that of EF, indicating that only a small part of EF is metabolized into CF (<5%) in both Tra catfish and prawn.  相似文献   
76.
全球禽肉生产和贸易中的沙门菌风险评估与控制   总被引:1,自引:0,他引:1  
1 禽源沙门菌对公共卫生的影响 在许多国家,沙门菌仍是引发食源性肠道疾病的主要原因.沙门菌通常存在于家畜、家禽中,也可在啮齿类、爬行类和鸟类等野生动物中发现.当农场的禽群感染沙门菌后,通常会有一部分家禽的消化道中携带沙门菌,但并无症状.随后,沙门菌可能会通过粪便污染感染动物屠体.  相似文献   
77.
1. The dietary inclusion of 15 and 25 g/kg mannose was associated with a reduction in the numbers of Salmonella enteritidis (PT4) in the caecal contents of chicks challenged by the food. The same benefit was not recorded for S. infantis, possibly because this strain, unlike S. enteritidis PT4, lacked mannose‐sensitive fimbriae.

2. The addition of 25 g/kg palm kernel meal (PKM), but not 20 g/kg desiccated coconut, to the food reduced the degree of salmonella colonisation in the intestinal tract of broiler chicks given diets contaminated with S. kedougou or S. enteritidis from the day of their arrival from the hatchery.

3. The beneficial effect of PKM was also demonstrated at an inclusion rate of 5 g/kg and was similar for preparations with a particle size of either < 150 μm or < 300 μm.

4. Day‐old birds challenged orally with S. enteritidis and given food supplemented with 25 g/kg PKM, became clear of infection by 3 weeks of age while birds given unsupplemented food remained infected.

5. These preliminary results suggest that the inclusion of PKM, which contains inter alia, oligosaccharides containing mannose, in the diet of chicks may reduce the extent to which the intestine is contaminated with salmonellas.  相似文献   

78.
Lymphokines are polypeptide factors produced by lymphocytes and other leukocytes, which modulate leukocyte activities in immune responses. Some of the more important lymphokines are reviewed in detail, with emphasis on those that have been cloned. These include interferon -alpha and -beta, interferon gamma, interleukin 2, interleukin 1, tumor necrosis factor and lymphotoxin, B lymphocyte growth factors, hemopoietic growth factors, and others.  相似文献   
79.
编者按:在家禽养殖中,饲料是支撑家禽生长的最基本元素.除去营养需要外,高度加工处理的饲料从一开始着眼于提高家禽的生产性能,以达到效率最优化.  相似文献   
80.
OBJECTIVE: To describe onset and duration of neuromuscular blockade induced by mivacurium chloride and its associated hemodynamic effects at 3 dosages in healthy dogs. ANIMALS: 7 Labrador Retrievers. PROCEDURE: Anesthesia was induced with thiopental and maintained with halothane in oxygen, and dogs were mechanically ventilated to end-tidal P(CO)2 between 35 and 40 mm Hg. Core temperature, end-tidal P(CO)2, and halothane concentration were kept constant throughout the experiment. Neuromuscular function was assessed by evaluation of the train-of-four response to a supramaximal electrical stimulus of 2 Hz applied to the ulnar nerve every 10 seconds. Blood for determination of plasma cholinesterase activity was obtained prior to administration of mivacurium, a bolus of which was administered IV, using a randomized Latin-square design for dosages of 0.01, 0.02, and 0.05 mg/kg of body weight. RESULTS: All dogs had typical plasma cholinesterase activity. After administration of mivacurium, differences were not evident between groups in heart rate, systolic, mean, or diastolic blood pressure, change at any time in heart rate, systolic, mean, or diastolic blood pressure, or pH. Interval from onset to 100% neuromuscular blockade was 3.92+/-1.70, 2.42+/-0.53, and 1.63+/-0.25 minutes at dosages of 0.01, 0.02, and 0.05 mg/kg, respectively. Duration of measurable neuromuscular blockade was 33.72+/-12.73, 65.38+/-12.82, and 151.0+/-38.50 minutes, respectively. Time of onset and duration of effect differed significantly among dosages. CONCLUSIONS AND CLINICAL RELEVANCE: Mivacurium provides good hemodynamic stability at the dosages tested. In dogs, this drug has a rapid onset and long duration of effect.  相似文献   
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