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21.
Detection of Toxoplasma gondii in the milk of experimentally infected lactating cats. 总被引:1,自引:0,他引:1
Tachyzoites of Toxoplasma gondii have been found in the milk of sheep, goats, cows and mice and infection by ingestion of raw goat milk has been documented in humans. Lactational transmission from infected cats to their kittens is suspected but the organism has not been detected in the milk. The purpose of this study was to demonstrate the presence of T. gondii in the milk of experimentally infected cats. Pregnant specific pathogen free cats were inoculated orally with T. gondii at various times prior to parturition. Feces were examined for oocyst shedding after sugar solution centrifugation. Milk was collected for polymerase chain reaction (PCR) and bioassay in mice. T. gondii was detected in the milk of five of six cats by either bioassay or PCR. 相似文献
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Javier Babí Almenar Benedetto Rugani Davide Geneletti Tim Brewer 《Landscape Ecology》2018,33(12):2047-2059
Context
The study of ecosystem services has extended its influence into spatial planning and landscape ecology, the integration of which can offer an opportunity to enhance the saliency, credibility, and legitimacy of landscape ecology in spatial planning issues.Objectives
This paper presents a conceptual framework suitable for spatial planning in human dominated environments supported by landscape ecological thinking. It seeks to facilitate the integration of ecosystem services into current practice, including landscape metrics as suitable indicators.Methods
A literature review supported the revision of existing open questions pertaining to ecosystem services as well as their integration into landscape ecology and spatial planning. A posterior reflection of the current state-of-the-art was then used as a basis for developing the spatial planning conceptual framework.Results and conclusion
The framework is articulated around four phases (characterisation, assessment, design, and monitoring) and three concepts (character, service, and value). It advocates integration of public participation, consideration of “landscape services”, the inclusion of ecosystem disservices, and the use of landscape metrics for qualitative assessment of services. As a result, the framework looks to enhance spatial planning practice by providing: (i) a better consideration of landscape configuration in the supply of services (ii) the integration of anthropogenic services with ecosystem services; (iii) the consideration of costs derived from ecosystems (e.g. disservices); and (iv) an aid to the understanding of ecosystem services terminology for spatial planning professionals and decision makers.25.
A pilot study was performed to investigate the impact of dietary vitamin D on circulating 25-hydroxyvitamin D (25[OH]D) metabolite concentrations in sugar gliders (Petaurus breviceps). The study with diets containing 0, 0.2 (low), or 0.4 (moderate) International Units vitamin D3 per gram of dry matter and fed to adults at 2 locations. Serum 25[OH]D concentrations did not differ between animals fed produce only (no added vitamin D–either D2 or D3) for 3 weeks (8.83 ± 0.98 nmol/L), n?=?6, or low dietary levels (7.86 ± 3.80 nmol/L), n?=?7, continuously for multiple years. Conversely, animals consuming diets containing moderate vitamin D3 levels displayed increased circulating concentrations (15.00 ± 3.59), n?=?8, after 3 weeks. Despite the response to diets supplemented with vitamin D, overall metabolite levels were low and may indicate minimal metabolic dependence on this nutrient in sugar gliders, similar to processes documented in other hindgut fermenters. 相似文献
26.
Q fever is a worldwide zoonotic disease caused by Coxiella burnetii. Although traditionally associated with livestock exposure, human infection has also been documented from contact with parturient cats. The goal of this study was to determine the prevalence of C burnetii DNA in uterine and vaginal tissues from healthy client-owned and shelter cats of north-central Colorado using polymerase chain reaction assay. Coxiella burnetii was not amplified from vaginal samples of any cat or uterine biopsies of shelter cats. However, a nucleotide sequence with 99% homology to C burnetii DNA was amplified from four of 47 (8.5%) uterine biopsies of client-owned cats. This study demonstrates that clinically normal cats in north-central Colorado can harbor C burnetii. Care should be taken when attending to parturient cats and contact with parturient secretions should be avoided. Additional studies are indicated to further characterize the role of cats in zoonotic Q fever. 相似文献
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Bayliss DB Morris AK Horta MC Labruna MB Radecki SV Hawley JR Brewer MM Lappin MR 《Journal of Feline Medicine and Surgery》2009,11(4):266-270
Rickettsia species antibodies have been detected in some cats but it is unknown whether infected cats develop clinical signs. The prevalence of Rickettsia species deoxyribonucleic acid (DNA) in blood from clinically ill cats has not been determined. The objective of this study was to determine if cats with fever (body temperature >or=102.5 degrees F [39.2 degrees C]) were more likely to have evidence of rickettsial infection than healthy, age-matched, control cats with a body temperature<102.5 degrees F. Rickettsia species polymerase chain reaction (PCR) assays were performed to detect rickettsial DNA extracted from blood (71 paired samples), indirect immunofluorescence assays (IFA) were performed to detect serum antibodies against Rickettsia felis (90 paired samples) and Rickettsia rickettsii (91 paired samples), and the results between pairs were compared. All samples were negative for Rickettsia species DNA. More cats with fever were seropositive for R felis or R rickettsii than control cats, but results were not statistically significant. Results of this pilot study failed to show an association between Rickettsia species DNA or Rickettsia species antibodies and fever. 相似文献
29.
The aim of recent breeding activity is to develop new wheat lines that incorporate desirable traits that are advantageous in baking and milling. Waxy wheats differ from wild‐type ones in functionality, end use, and biochemical contents (e.g., amylopectin/amylose ratios and lipid contents). Previous waxy wheat investigations focused only on differences in the carbohydrate and protein fractions. The goals of this work were to apply chemical imaging to discriminate between waxy and wild‐type wheats and to define contrasting lipid profiles that occur in the deliberate alteration of the carbohydrate fraction. Fourier transform infrared (IR) microspectroscopic in situ probing and imaging of kernel sections was applied with the use of high spatial resolution. Mid‐IR provided chemical manifestation of lipid genetic expression in isogenic samples. All waxy wheat specimens contained higher lipid content, mostly in the form of glycolipids. The relative lipid profiles differed among common, durum, and waxy wheats. Isogenic partial waxy cultivars and advanced breeding lines were also examined. 相似文献
30.
Brewer L 《Science (New York, N.Y.)》1968,161(3837):115-122