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41.
42.
A colony of cats affected with hypertrophic feline muscular dystrophy was used to study the occurrence of cardiomyopathy associated with dystrophin deficiency. Affected male and female cats, obligate carrier females, and unaffected healthy littermates were followed from 12 weeks of age into adulthood. Thoracic radiography, 2-D echocardiography, and 2-D-derived M-mode echocardiography were performed at 3-month intervals until 12 months of age and regularly thereafter. From 9 months of age, all affected cats had larger hearts than normal and carrier animals. Left ventricular wall thickness in systole and in diastole and interventricular septal thickness in systole were greater in affected cats 12 months and older when compared with normal or heterozygous animals (P < .05). The myocardium of affected cats was diffusely hypoechoic and thickened. Multiple hyperechoic foci were in the myocardium and papillary musculature. Shortening fraction was normal in all cats. Changes seen in carrier females included enlargement and hyperechogenicity of the papillary musculature after the age of 2 years. Gross and light microscopic examination revealed left ventricular wall thickening with multiple foci of mineralization in 2 of 5 hearts from dystrophin-deficient cats. Although approximately 10% of the normal dystrophin amount was present in the skeletal muscle, dystrophin could not be detected in the myocardium. Early onset concentric myocardial hypertrophy was present in all adult cats. Lesions were mainly localized in the myocardium of the left ventricular free wall and interventricular septum, papillary musculature, and the endocardium. Clinical signs of heart failure developed only infrequently in cats with hypertrophic feline muscular dystrophy.  相似文献   
43.

Background

Red foxes (Vulpes vulpes L.) have become successful inhabitants of urban areas in recent years. However, our knowledge about the occurrence, distribution and association with land uses of these urban foxes is poor, partly because many favoured habitats are on private properties and therefore hardly accessible to scientists. We assumed that citizen science, i.e. the involvement of the public, could enable researchers to bridge this information gap. We analysed 1179 fox sightings in the city of Vienna, Austria reported via citizen science projects to examine relationships between foxes and the surrounding land use classes as well as sociodemographic parameters.

Results

Conditional probabilities of encountering foxes were substantially higher in gardens, areas with a low building density, parks or squares as compared to agricultural areas, industrial areas or forests. Generalized linear model analyses showed that sociodemographic parameters such as education levels, district area, population density and average household income additionally improved the predictability of fox sightings.

Conclusions

Reports of fox sightings by citizen scientists might help to support the establishment of wildlife management in cities. Additionally, these data could be used to address public health issues in relation with red foxes as they can carry zoonoses that are also dangerous to humans.
  相似文献   
44.
Objectives – The aim of this study is to describe the prevalence of postoperative laminitis in colic cases and to determine if low-molecular-weight heparin (LMWH) is effective in preventing this complication.
Design – Retrospective clinical study.
Animals – Client-owned horses.
Interventions – SC administration of enoxaparin during the postoperative period.
Measurements and Main Results – Medical records of 360 horses undergoing surgery for colic and surviving at least 3 days were evaluated. Fifty-six horses admitted before 1995 did not receive LMWH (control group) and 304 admitted after 1995 received LMWH as a prophylaxis for laminitis (treatment group). Three grades of severity were defined for laminitis. Prevalence and severity of laminitis were compared between the 2 groups. Several parameters recorded on admission (sex, age, breed, site and nature of the disease, heart rate, PCV, gravity score, and shock score) and the administration of LMWH were tested as risk factors in the development of laminitis in a logistic regression procedure. Prevalence and grade of laminitis were significantly lower in the treatment group. Only the absence of LMWH was recognized as a significant risk factor in the logistic regression model.
Conclusions – The administration of LMWH appears to be effective in the prophylaxis of laminitis following colic surgery and may be useful in the postoperative management of these horses.  相似文献   
45.
A prospective cohort observational study was conducted to investigate the seroprevalence of Anaplasma marginale in Iowa feedlots and its association with morbidity, mortality, and treatment costs. Blood samples were taken from 659 calves from 31 consigners at processing and classified as seropositive to A. marginale using a competitive enzyme-linked immunosorbent assay (cELISA) with a 30% cutoff. Health and production parameters were modeled by A. marginale serostatus with mixed model regression analysis. The apparent prevalence of seropositive cattle was 15.17% (100/659). When the cELISA positive cutoff was at 42% inhibition, the apparent prevalence was 5.00% (33/659). There was no significant association between A. marginale serostatus and production parameters; however, seropositive status had a weak positive association with undifferentiated fever (P = 0.17). Although prevalence of anaplasmosis in Iowa feedlots is higher than reported in Montana-sourced calves arriving in Canadian feedlots, this was not associated with increased production costs.  相似文献   
46.
ObjectiveTo describe the pharmacokinetics, cortisol response and behavioral changes associated with administration of sub-anesthetic xylazine and ketamine prior to castration.Study designProspective, randomized experiment.AnimalsTwenty-two male beef calves (260-310 kg).MethodsCalves were randomly assigned to receive the following treatment immediately prior to surgical or simulated castration; 1) uncastrated, placebo-treated control (CONT) (n = 4), 2) Castrated, placebo treated control (CAST) (n = 6), 3) castrated with intravenous xylazine (X) (0.05 mg kg?1) (n = 6), and 4) castrated with IV xylazine (X) (0.05 mg kg?1) combined with ketamine (K) (0.1 mg kg?1) (n = 6). Blood samples collected over 10 hours post-castration were analyzed by LC-MS-MS for drug concentrations and chemiluminescent immunoassay for cortisol determination.ResultsDrug concentrations during the first 60 minutes post-castration fit a one-compartment open model with first-order elimination. The harmonic mean elimination half-lives (± pseudo SD) for X, X with K and K were 12.9 ± 1.2, 11.2 ± 3.1 and 10.6 ± 2.8 minutes, respectively. The proportion of the total area under the effect curve (AUEC) for cortisol during this period was significantly lower in the X group (13 ± 3%; p = 0.006) and the X+K group (14 ± 2%; p = 0.016) compared with the CAST calves (21 ± 2%). However, after 300 minutes the AUEC in the X group was higher than CAST. Significantly more calves demonstrated attitude that was unchanged from pre-manipulation behavior in the CONT (p = 0.021) and X+K treated calves (p = 0.0051) compared with the CAST calves.ConclusionsBehavioral changes and lower serum cortisol concentrations during the first 60 minutes post-castration were associated with quantifiable xylazine and ketamine concentrations.Clinical relevanceLow doses of xylazine and ketamine administered immediately prior to castration may offer a safe, efficacious and cost-effective systemically administered alternative or adjunct to local anesthesia.  相似文献   
47.
48.
This paper presents an assessment of a large, national-scale alien plant control program that has operated in South Africa for 15 years. We reviewed data from three national-level estimates of the extent of invasion, records of the costs and spatial extent of invasive species control operations, assessments of the effectiveness of biological control, and smaller-scale studies. The 19 most important invasive taxa, mainly trees, in terrestrial biomes were identified. The effectiveness of control efforts on the extent of invasion of these taxa was assessed. Control costs over 15 years amounted to 3.2 billion rands (US$457 million), more than half of which was spent on 10 taxa, the most prominent being in the genera Acacia, Prosopis, Pinus and Eucalyptus. Despite substantial spending, control operations were in many cases applied to a relatively small portion of the estimated invaded area, and invasions appear to have increased, and remain a serious threat, in many biomes. Our findings suggest that South Africa’s national-scale strategy to clear invasive alien plants should be substantially modified if impacts are to be effectively mitigated. Rather than attempting to control all species, and to operate in all areas, a more focused approach is called for. This would include prioritising both the species and the areas, and setting goals and monitoring the degree to which they are achieved, within a framework of adaptive management. A greater portion of funding should also be directed towards biological control, where successes have been most notable.  相似文献   
49.
50.
Invasion of non-native species is among the top threats for the biodiversity and functioning of native and agricultural ecosystems worldwide. We investigated whether the herbivory of the slug Arion vulgaris (formerly Arion lusitanicus; Gastropoda), that is listed among the 100 worst alien species in Europe, is affected by soil organisms commonly present in terrestrial ecosystems (i.e. earthworms—Annelida: Lumbricidae and arbuscular mycorrhizal fungi—AMF, Glomerales). We hypothesized that slug herbivory would be affected by soil organisms via altered plant nutrient availability and plant quality. In a greenhouse experiment, we created a simple plant community consisting of a grass, a forb, and a legume species and inoculated these systems with either two earthworm species and/or four AMF taxa. Slugs were introduced after plants were established. Earthworms significantly reduced total slug herbivory in AMF-inoculated plant communities (P?=?0.013). Across plant species, earthworms increased leaf total N and secondary metabolites, AMF decreased leaf thickness. Mycorrhizae induced a shift in slug feeding preference from non-legumes to legumes; the grass was generally avoided by slugs. AMF effects on legume herbivory can partly be explained by the AMF-induced increase in total N and decrease in C/N ratio; earthworm effects are less clear as no worm-induced alterations of legume plant chemistry were observed. The presence of earthworms increased average AMF colonization of plant roots by 140 % (P?<?0.001). Total shoot mass was significantly increased by AMF (P?<?0.001). These data suggest that the feeding behavior of this invasive slug is altered by a belowground control of plant chemical quality and community structure.  相似文献   
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