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排序方式: 共有470条查询结果,搜索用时 31 毫秒
101.
Federica Di Profio Vittorio Sarchese Irene Melegari Andrea Palombieri Ivano Massirio Sandra Bermudez Sanchez Klaus Gunther Friedrich Federico Coccia Fulvio Marsilio Vito Martella Barbara Di Martino 《Zoonoses and public health》2019,66(3):310-315
Noroviruses (NoVs) are a major cause of epidemic gastroenteritis in children and adults. Several pieces of evidence suggest that viruses genetically and antigenically closely related to human NoVs might infect animals, raising public health concerns about potential cross‐species transmission. The natural susceptibility of non‐human primates (NPHs) to human NoV infections has already been reported, but a limited amount of data is currently available. In order to start filling this gap, we screened a total of 86 serum samples of seven different species of NPHs housed at the Zoological Garden (Bioparco) of Rome (Italy), collected between 2001 and 2017, using an enzyme‐linked immunosorbent assay (ELISA) based on virus‐like particles (VLPs) of human GII.4 and GIV.1 NoVs. Antibodies specific for both genotypes were detected with an overall prevalence of 32.6%. In detail, IgG antibodies against GII.4 NoVs were found in 18 Japanese macaques (29.0%, 18/62), a mandrill (10.0%, 1/10), a white‐crowned mangabey (16.6%, 1/6) and in an orangutan (33.3%, 1/3). Twelve macaques (19.3%, 12/62), five mandrills (50.0%, 5/10), two chimpanzees (100%, 2/2) and a white‐crowned mangabey (16.6%, 1/6) showed antibodies for GIV.1 NoVs. The findings of this study confirm the natural susceptibility of captive NHPs to GII NoV infections. In addition, IgG antibodies against GIV.1 were detected, suggesting that NHPs are exposed to GIV NoVs or to antigenically related NoV strains. 相似文献
102.
Irene COBO‐SIM
N Beln MNDEZ‐CEA Hctor PORTILLO Fausto ELVIR Hermes VEGA Francisco Javier GALLEGO Gustavo FONTECHA 《Integrative zoology》2019,14(5):422-434
Biosphere reserves are protected areas whose purpose is to combine conservation and sustainable development. However, their effectiveness has not been tested sufficiently, especially from an ecological and genetic approach. In this sense, the Peromyscus genus represents an excellent bioindicator to address these questions, due to its short life and high evolutionary rate and fecundity. For conservation managers, genetic structure can increase the rate of loss of genetic diversity because alleles exclusive of a subpopulation are more likely to disappear as a consequence of genetic drift in comparison with a panmictic population. Here we analyzed the abundance, movement distances, morphology/morphometry and genetic structure of 3 populations of Mexican deer mouse (Peromyscus mexicanus) located in different protected zones of La Tigra National Park (Honduras). Our results are consistent among the 3 approaches and showed the highest values of abundance, morphometry and genetic diversity in the population located at the core zone, whereas non‐statistically significant differences were found between buffer and transition zone populations, suggesting suitable effectiveness of conservation management in the core zone but a lack of ecological buffering function of the other zones. In addition, the low movement distances and high genetic structure among the studied populations provide evidence of poor conservation management in the buffer and transition zone. Thus, we discuss the utility of the novel methodology used in this work, combining morphometry, abundance and genetics, in testing the effectiveness of conservation strategies in biosphere reserves, and the value of the Peromyscus genus as a bioindicator. 相似文献
103.
Validation of a paraoxon‐based method for measurement of paraoxonase (PON‐1) activity and establishment of RIs in horses
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104.
Changes in the quality of meat (Longissimus thoracis et lumborum) from Kamieniec lambs during long‐term freezer storage
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Tomasz Daszkiewicz Cezary Purwin Dorota Kubiak Maja Fijałkowska Emilia Kozłowska Zofia Antoszkiewicz 《Animal Science Journal》2018,89(9):1323-1330
The aim of this study was to determine changes in the quality of lamb meat (Longissimus thoracis et lumborum), which was vacuum‐packaged and freezer‐stored (?26°C) for 6 and 12 months. The experiment was performed on 12 male lambs of the Kamieniec Longwool breed, raised to 106 days of age. In comparison with fresh meat, thawed meat was characterized by lower ash content, higher pH, greater natural drip loss and cooking loss, and lower scores for taste intensity. Vacuum packaging and low‐temperature storage protected lamb meat against oxidative changes, and alleviated the adverse effects of oxidation on the color, aroma and taste of meat. It can be concluded that freezer storage (?26°C) of vacuum‐packaged meat can help meet consumer demand for lamb meat products in periods when fresh meat is unavailable. However, it should be noted that long‐term frozen storage induces undesirable changes in meat quality, including a decrease in water‐holding capacity and taste intensity. 相似文献
105.
Jana Boben Petra Kramberger Nataša Petrovič Katarina Cankar Matjaž Peterka Aleš Štrancar Maja Ravnikar 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):59-71
A quantitative RT real-time PCR method was developed for the detection and quantification of Tomato mosaic virus (ToMV) in irrigation waters. These have rarely been monitored for the presence of plant pathogenic viruses, mostly due to the lack of efficient and sensitive detection methods. The newly developed method presented here offers a novel approach in monitoring the health status of environmental waters. ToMV was reliably detected at as low as 12 viral particles per real-time PCR reaction, which corresponds to the initial concentration of approximately 4.2 × 10?10 mg (6,300 viral particles) of ToMV per ml of sample. The sensitivity of the method was further improved by including the Convective Interaction Media® (CIM) monolithic chromatographic columns for quick and efficient concentration of original water samples. Seven out of nine water sources from different locations in Slovenia tested positive for ToMV, after concentrating the sample. Four samples tested ToMV-positive without the concentrating procedure. The presence and integrity of infective ToMV particles in the original sample, as well as in the chromatographic fraction, was confirmed using different methods from test plants, DAS ELISA to electron microscopy and real-time PCR. In this study, we propose a unique and simple diagnostic scheme for rapid, efficient, and sensitive monitoring of irrigation waters that could also be adopted for other plant, human or animal viruses. 相似文献
106.
von Klopmann T Boettcher IC Rotermund A Rohn K Tipold A 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(3):516-522
Euthyroid sick syndrome is a common finding in dogs and is attributable to nonthyroidal illness or treatment with any of a variety of drugs such as phenobarbital. In dogs with epilepsy, treatment with anticonvulsant drugs can lead to subnormal plasma thyroid hormone concentrations despite normal thyroid function. One-hundred thirteen dogs with seizure activity were retrospectively evaluated to determine the influence of idiopathic epilepsy (IE) on thyroid hormone concentrations. Blood samples were taken from 60 dogs with IE before initiation of anticonvulsant therapy. Control groups consisted of 34 dogs with IE and receiving anticonvulsants and 19 dogs with secondary epilepsy. Thyroid concentrations consistent with euthyroid sick syndrome were diagnosed in 38% of dogs with untreated IE without clinical signs of hypothyroidism or concomitant diseases. There was a significant correlation (r = 0.363, P = .01) between seizure frequency and plasma thyroid hormone concentrations: the longer the interval between 2 seizure events, the higher the serum total thyroxine concentration. There was no correlation between the degree of alteration of thyroid hormone concentrations and the time span between the most recent seizure event and blood collection, the type of the most recent seizure event, the duration of the complete seizure history, or the predominant seizure type. These results suggest that IE can be a reason for euthyroid sick syndrome in dogs. The effect of phenobarbital on plasma thyroid hormone concentrations must be investigated in future studies, as it might be less pronounced than expected. 相似文献
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Marine recirculation aquaculture system (RAS) is a prominent technology within fish farming. However, the nitrifying bacteria in the biofilter have low growth rates, which can make the biofilter activation a long and delicate process with periods of low nitrification rates and variations in water quality. More knowledge on the microbial development in biofilters is therefore needed in order to understand the rearing conditions that favour optimal activation of the biofilters. In this case study, we investigated the activation of two biofilters in a marine RAS for Atlantic salmon post‐smolt associated with either high or low stocking densities of fish by monitoring the microbial communities and chemical composition. The results showed that the microbial communities in both biofilters were similar during the first rearing cycle, despite variations in the water quality. Nitrifying bacteria were established in both biofilters; however, the biofilter associated with low stocking density had the highest relative abundance of ammonia‐oxidizing Nitrosococcus (1.0%) and nitrite‐oxidizing Nitrospira (2.1%) at the end of the first rearing cycle, while the relative abundance of ammonia‐oxidizing Nitrosomonas (2.3%–2.9%) was similar in both biofilters. Our study showed that low fish stocking density during the first rearing cycle provided low and steady concentrations of ammonium, nitrite and organic load, which can stimulate rapid development of a nitrifying population in new marine RAS biofilters. 相似文献