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81.
OBJECTIVE: To determine the role of nitric oxide and an apamin-sensitive nonadrenergic noncholingeric inhibitory transmitter on contractility of the ventral colon of horses. SAMPLE POPULATION: Strips of the circular and longitudinal muscle layers and taenia of the ventral colon from 14 horses. PROCEDURE: Muscle strips were suspended in tissue baths and attached to force transducers. Contractile activity of circular, longitudinal, and taenia muscle strips in response to electrical field stimulation was measured after addition of apamin and a nitric oxide inhibitor, N-nitro-L-arginine methyl ester (L-NAME). RESULTS: Electrical field stimulation reduced contractile activity in the circular muscle layer and taenia but not the longitudinal muscle layer. Addition of L-NAME significantly reduced inhibitory contractile activity at all frequencies for the circular muscle layer, whereas a significant effect was evident for the taenia only at the highest frequency. The combination of L-NAME and apamin resulted in a significant reduction in inhibition of the taenia at all frequencies but for circular muscle only at lower frequencies. CONCLUSIONS AND CLINICAL RELEVANCE: Nitric oxide and an apamin-sensitive neurotransmitter appear to mediate a component of inhibitory transmission in the circular muscle and taenia, but not the longitudinal muscle layer, of the equine ventral colon. Nitric oxide has a role in regulating contractile activity of the equine ventral colon, and nitric oxide synthase inhibitors may be useful in horses with ileus of the large colon.  相似文献   
82.
Until recent years, relatively little attention has been given to beef cattle transportation management and research in the United States As oulined in this article, it is clear that there are significant physiologic changes occurring in cattle as a result of transport and handling. These physiologic changes encompass, among others, effects on immune system function, disease incidence, and carcass quality. Significant advancements have been made during the past decade in the use of appropriate cattle-handling techniques, facility design,and research promoting our understanding and the attenuation of transport stress. Many issues surrounding livestock transport, such as temperature and ventilation during transit, use of rest stops, pretransit feeding regimens, and incidence of disease transmission via transport vehicles, need further research to enable continued provision of science-based recommendations to the livestock and transportation industries.  相似文献   
83.
The number of people keeping reptiles in captivity has markedly increased, and widespread inappropriate husbandry will result in an increasing incidence of the diagnosis of hepatic lipidosis(HL). It may become apparent that some species of snake have predisposition to develop HL. In the specific instance of the genus Aspidites, alterations to the usual husbandry that limit feeding and thereby body weight should markedly lessen the chance of the animal's developing HL. It is important for clinicians to develop a more aggressive approach to these cases and to build a bank of data with which to promote understanding of this common malady.  相似文献   
84.
The nonsteroidal antiinflammatory drug ketoprofen (KTP) is a commonly used antiinflammatory and analgesic agent in reptile medicine, but no studies documenting its pharmacokinetics in this species have been published. Ketoprofen was administered as a racemic mixture to green iguanas (Iguana iguana) intravenously (i.v.) and intramuscularly (i.m.) at 2 mg/kg. Pharmacokinetic analyses were performed and indicated that ketoprofen in iguanas administered by the intravenous route has a classical two-compartmental distribution pattern, a slow clearance (67 ml/ kg/hr) and a long terminal half-life (31 hr) compared to ketoprofen studies reported in mammals. When delivered by the intramuscular route, bioavailability was 78%. These data indicate the daily dosing that is generally recommended for reptile patients, as an extrapolation from mammalian data, may be more frequent than necessary.  相似文献   
85.
Safe and effective echocardiography would represent a valuable tool for marine mammal veterinarians and physiologists evaluating the dolphin heart. Unfortunately, conventional ultrasound technology (transthoracic echocardiography) has been limited by logistic, anatomic, and behavioral challenges. Five mature male Atlantic bottlenose dolphins (Tursiops truncatus) were trained for echocardiographic imaging (four for both transthoracic and transesophageal imaging, and one for only transthoracic imaging). It was noted that transesophageal image quality transiently improved when the dolphins spontaneously exhaled. Subsequently, dolphins were conditioned to hold their breath following forced exhalation, and imaging proceeded during such behavioral breath holds. Over 25 transthoracic and 100 transesophageal echocardiographic studies were performed, including both two-dimensional imaging and color flow mapping. Transthoracic imaging yielded poor-quality images of only small portions of the heart. In contrast, transesophageal imaging, which improved dramatically with behavioral breath holding following exhalation, yielded consistently high-quality images of the entire heart (mitral, tricuspid, aortic, and pulmonary valves, atrial and ventricular septa, left and right atria, left and right ventricles, and ascending aorta and main pulmonary artery). Color flow mapping demonstrated mild tricuspid regurgitation in all dolphins, and mild aortic regurgitation in one dolphin found to have a pedunculated mass arising from the sinutubular junction just above the aortic valve. There were no complications in nonsedated dolphins. The heart of the bottlenose dolphin can be safely, effectively, and reproducibly evaluated with the use of transesophageal echocardiography in conjunction with behavioral breath holding following forced exhalation. This approach, and the normative echocardiographic data generated from this work, lays the foundation for future echocardiographic studies of cetaceans.  相似文献   
86.
This study describes the pharmacokinetics of enrofloxacin following oral and i.v. administration to goral (Nemorrhaedus goral arnouxianus). The objective of this study was to expand upon current antimicrobial treatment options available for use in goral by measuring plasma concentrations and examining the pharmacokinetics of enrofloxacin in these animals. Two single-dose treatments of enrofloxacin were administered to four goral in a crossover design. Single-dose treatments consisted of administration of injectable enrofloxacin i.v. (5 mg/kg) and enrofloxacin tablets (136 mg chewable tablets) dissolved in a grain slurry and administered p.o. (10 mg/kg). Plasma levels of enrofloxacin and its metabolite ciprofloxacin were measured with the use of high-performance liquid chromatography with UV detection. Plasma volume of distribution for i.v. enrofloxacin was 2.15 - 1.01 L/kg, with a mean elimination half-life of 13.3 hr and total body clearance of 0.19+/-0.14 L/kg/hr. The maximum plasma concentration measured for oral enrofloxacin was 2.77 microg/ml, with a mean half-life of 5.2 hr and systemic availability of 14.6%. The area under the plasma concentration over time curve (AUC) for oral enrofloxacin was 21.06 microg/hr/ml. The area under the plasma concentration over time curve generated for oral enrofloxacin in goral yields an area under the plasma concentration over time curve to minimum inhibitory concentration ratio > 100 for many gram-positive and gram-negative bacterial pathogens common to small ruminants. Based on these results, oral enrofloxacin may be considered for further study as a treatment option for susceptible infections in goral.  相似文献   
87.
A free-ranging, adult male Florida panther (Puma concolor coryi) was immobilized and evaluated for hematuria following routine capture. Prior to anesthetic recovery, the panther was fitted with a telemetry collar. After an initially quiet recovery, the panther began thrashing in the transport cage, and was again immobilized. Pink foam was evident from the nostrils, and crackles were ausculted over the chest, indicating pulmonary edema. Postobstructive pulmonary edema was diagnosed based on history, clinical signs, radiographic evaluation, and blood gas analysis. The animal was treated intensively for several hours with diuretics, oxygen, and manual ventilation. The panther responded rapidly to therapy and was released back into the wild 48 hr after presentation. Postobstructive pulmonary edema, also called negative-pressure pulmonary edema, may be underrecognized in veterinary medicine. In this case, the telemetry collar, in conjunction with anesthetic recovery in a small transport crate, may have contributed to tracheal obstruction. Wildlife veterinarians and biologists should be aware of the risk of airway obstruction when placing tracking collars, and animals should be continuously monitored during anesthetic recovery to ensure the presence of a patent airway.  相似文献   
88.
89.
A juvenile cheetah (Acinonyx jubatus) died with rapidly progressive pyrexia, tachypnea, abdominal effusion, and hepatomegaly. Postmortem examination revealed lesions consistent with acute disseminated infection with Toxoplasma gondii. The presence of this organism was confirmed in multiple organs by immunohistochemistry and polymerase chain reaction. To the best of our knowledge, we propose this to be the first reported case of primary acute disseminated toxoplasmosis in a cheetah.  相似文献   
90.
Sequence parts of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were analysed to screen for the intraspecific variability of a non-coding genomic region in 15 Plasmopara halstedii populations of different pathotype and geographic origin. Samples revealed uniformity in a ca. 790 Bp fragment comprising of the ITS-1, 5.8S and front parts of the ITS-2. In contrast, clear differences were found in a ca. 810 Bp fragment of the ITS-2 thus allowing differentiation between populations of pathotype 100, 310 and 330 and a group of populations representing pathotypes 700, 701, 703, 710 and 730. Samples of pathotypes 700 to730 originated from Slovakia, France, and Germany, but were uniform in both ITS sequence parts, thus indicating very recent origin of these highly aggressive physiological races. The potential use of ITS sequences for pathotype differentiation and phylogenetic studies in P. halstedii is discussed.  相似文献   
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