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11.
A 16-year-old, castrated, male English cocker spaniel dog was presented due to generalized alopecia. Routine clinical pathology, endocrine and abdominal ultrasonography results were consistent with a diagnosis of pituitary-dependent hyperadrenocorticism. The adenohypophyseal lesion was clearly visualized on both 3 T and 7 T magnetic resonance imaging (MRI) of the pituitary gland. Although biochemical and MRI findings were consistent with a functional pituitary microtumor, a pituitary lesion was not detected using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). This report firstly describes the application of high-resolution FDG-PET to a spontaneous pituitary microtumor in a dog.  相似文献   
12.
A biological attack on livestock or poultry could result in the loss of valuable animals, costs related to the containment of outbreaks and the disposal of carcasses, lost trade and other economic effects involving suppliers, transporters, distributors and restaurants; however, it is not possible to secure all livestock, and livestock are much less well guarded than human targets. Thus, the vulnerability of the livestock industry to the introduction of biological agents varies for the following reasons: (i) the majority of lethal and contagious biological agents are environmentally resilient, endemic in foreign countries and harmless to humans, making it easier for terrorists to acquire, handle and deploy these pathogens, (ii) with animals concentrated in fewer production facilities and frequently transported between these facilities, a single pathogen introduction could cause widespread infection and (iii) the extent of human travel around the globe makes it difficult to exclude exotic animal diseases as possible biological agents. Historically, many governments have developed and planned to use biological agents for direct attacks on livestock or poultry. In the past, developed nations have actively developed biological weapons to target animals. The potential spectrum of bioterrorism ranges from isolated acts against individuals by individuals to tactical and strategic military attacks and state‐sponsored international terrorism intended to cause mass casualties in animals, humans or both. This review provides an overview of the past development and use of biological weapons and describes potential future attacks.  相似文献   
13.
Discovery of Helicobacter (H.) pylori has led to a fundamental change in our understanding of gastric diseases in humans. Previous studies have found various Helicobacter spp. in dogs and cats, and pets have been questioned as a zoonotic carrier. The present study surveyed the Helicobacter infections and investigated the presence of H. felis and H. pylori infections in domestic and feral cats in Korea. Sixty-four domestic cats and 101 feral cats were selected from an animal shelter. Saliva and feces were evaluated by Helicobacter genus-specific polymerase chain reaction (PCR). Genus-specific PCR positive samples were further evaluated for H. felis and H. pylori using specific primer pairs. Thirty-six of 64 (56.3%) samples from domestic cats and 92 of 101 (91.1%) samples from feral cats were PCR positive; the positive rate of feces samples was higher than that of saliva samples in both groups. H. felis and H. pylori species-specific PCR was uniformly negative. The prevalence of Helicobacter spp. in feral cats was approximately two-fold higher than that of domestic cats. The fecal-oral route may be more a common transmission route not only between cats but also in humans.  相似文献   
14.
In a feeding experiment (54 piglets) and a slaughtering test for the registration of tract and digesta properties (15 piglets) the influence of rations with 69% rye (R) or wheat (W) with and without a supplement of 200 mg of the chinoxalin derivate Bisergon/kg DM (rations RB and WB) was studied. In the sequence R, RB, W and WB the feed intake in the test period of 3 weeks after weaning amounted to 581, 651, 583 and 764 g, weight gain to 314, 365, 319 and 424 g per animal and day. In the same sequence the concentration of organic acids in the stomach amounted to 41, 5, 25 and 18 mmol per 100 g dry matter and in the colon to 106, 83, 64 and 62. Bisergon caused a redistribution of the digesta from the stomach to the large intestine and a more rapid emptying of the stomach as well. Rye caused extreme fermentation processes in the front part of the tract and Bisergon clearly has ergotropic qualities for the stabilization of the intestinal flora.  相似文献   
15.
We compared the immunoreactivity and numbers of tyrosine hydroxylase (TH) immunoreactive neurons and neuropil in the paraventricular nucleus (PVN) of the hypothalamus between the seizure sensitive (SS) and seizure resistant (SR) gerbils. The distributional pattern of TH immunoreactivity was similar in both groups: TH immunoreactivity was seen mainly in magnocellular neurons of the PVN. However, total TH immunoreactivity in the neurons and neuropil in the SS gerbils was significantly lower than that in the SR gerbils. In addition, the number of TH immunoreactive neurons in the SS gerbils was also much lower than those in the SR gerbils. These results indicate that SS gerbils have a low TH immunoreactivity in the hypothalamic PVN compared with that in SR gerbils.  相似文献   
16.
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors.  相似文献   
17.
ObjectiveTo further characterize arrhythmic mechanisms in German shepherd dogs (GSDs) affected with inherited ventricular arrhythmias by evaluating intracellular calcium cycling and expression of calcium handling genes.AnimalsTwenty five GSDs, 9 backcross dogs, and 6 normal mongrel dogs (controls) were studied. The GSDs and backcross dogs were from a research colony of inherited ventricular arrhythmias. The control research dogs were purchased.MethodsAction potentials (APs) and pseudo-electrocardiograms (ECG) were recorded from left ventricular (LV) wedge preparations of GSDs and normal dogs. Midmyocardial (Mid) LV cells from GSDs and normal mongrels were isolated by enzymatic digestion. Cells were either field stimulated or voltage clamped and calcium transients were measured by confocal microscopy using the indicator Fluo-3AM. Expression of calcium handling genes was measured by quantitative RT-PCR.ResultsMean calcium transient decay (tau) was not different between affected GSDs and control dogs, but striking cell-to-cell variability for tau was observed within affected GSDs and between affected GSDs and controls (P < 0.0001 each); within-dog variability accounted for 75% of total variability. Calcium sparks and afterdepolarizations occurred in GSD but not control cells. ATP2A2/SERCA2a expression was significantly reduced (P = 0.0063) in affected GSDs and inversely correlated (P = 0.0006) with severity of ventricular arrhythmias.ConclusionsGerman shepherd dogs with inherited ventricular arrhythmias have electrophysiologic abnormalities in calcium cycling associated with reduced ATP2A2/SERCA2a expression. These animals provide a unique opportunity to study calcium remodeling at the genetic and molecular level in familial ventricular arrhythmias.  相似文献   
18.
A total of 336 1‐day‐old male Korean native ducks (KND) were used in a completely randomized design with seven dietary methionine levels (0.30–0.90% with 0.1% increment) to determine the methionine requirement of male Korean native ducks for 3 weeks after hatching. Each dietary treatment had six replicates with eight ducklings per pen. One duckling from each pen (n = 6) was sacrificed to weigh empty body and drumsticks at the end of the experiment. Final body weight and weight gain of 3 weeks old KND were increased with increasing dietary methionine levels up to 0.4%, and then decreased (< 0.05) with a further increasing dietary methionine level. In contrast, feed conversion ratio of the KND decreased up to 0.4% and increased (< 0.05) with the increasing dietary methionine level. Both empty body weight and proportions of empty body weight were linearly increased (< 0.05) while the dietary methionine level elevated up to 0.4%. Estimated dietary methionine requirement for maximum body weights, daily gain and minimum feed conversion ratio were 0.36, 0.39 and 0.40%, respectively, when it was fitted into linear‐ and quadratic‐plateau models.  相似文献   
19.
The efficacy of amoxicillin sodium for controlling field and experimental Streptococcus iniae and S. parauberis infections in olive flounder (Paralichthys olivaceus) was evaluated after a single intramuscular administration. Furthermore, the minimal inhibitory concentrations (MIC) against 21 Streptococcus strains were determined. In addition, the pharmacokinetics and residue depletion in olive flounder were investigated. Single intramuscular doses of amoxicillin sodium at 20, 40, 80, and 160 mg/kg b.w. fish significantly reduced cumulative mortality rates to 18.8–31.3% (< 0.05) for S. iniae and to 5.0–15.0% (< 0.01) for S. parauberis, whereas the S. iniae‐ and S. parauberis‐infected positive control groups showed cumulative mortality rates of 68.8% and 60.0%, respectively. In a S. parauberis outbreak, amoxicillin sodium reduced the cumulative mortality rate to 7.5% and 4.8% at 20 and 40 mg/kg b.w. fish, respectively, whereas that of the untreated control group was 35.2%. Peak plasma concentrations (Cmax) following a single intramuscular dose of 40 and 80 mg/kg b.w. fish were 62.64 (Tmax, 1.59 h) and 87.61 (Tmax, 3.02 h) μg/mL, respectively, with large AUC0?t/MIC and Cmax/MIC ratios, and sufficient T > MIC (time for maintaining plasma drug concentration greater than MICs) for S. iniae and S. parauberis. The estimated withdrawal period of amoxicillin sodium from muscle of olive flounder was about 8 days at 40 mg/kg b.w. fish (at 22 ± 1 °C). These results demonstrated a single intramuscular administration of amoxicillin sodium to be effective against streptococcosis in olive flounder.  相似文献   
20.
The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.  相似文献   
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