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81.
Ten Merino ewes were given a single Permasel pellet (containing 5% of elementary selenium) orally and examined for the release of selenium in the reticulum by determining glutathione enzyme activity of the whole blood haemolysate over a period of 12 months. As compared to the controls, the treated ewes exhibited a significant elevation in glutathione peroxidase activity for 8 months, indicating an acceptable persistence of the product tested.  相似文献   
82.
Factors to consider when deciding on a surgical approach to explore the abdomen of a horse include facilities and equipment available, experience of the surgeon, temperament of the horse and the necessity for cosmesis. An approach performed with the horse standing may be necessary when anaesthesia or recovery from anaesthesia is considered risky or when the owner imposes a financial limitation that does not allow surgery to be performed with the horse anaesthetised. Approaches performed with the horse standing include the flank and colpotomy approaches. Each approach has benefits and risks inherent to it.  相似文献   
83.
Hepatitis E virus is a major causative agent of acute hepatitis worldwide. Despite its zoonotic potential, there is limited information about the natural chain of hepevirus infection in wildlife, and the potential reservoir species. In this study, we performed a HEV survey by heminested RT‐PCR on rodent samples from an urban environment (in the city of Pécs, Hungary) and investigated the prevalence of the virus among these native rodent species (Apodemus agrarius, Apodemus flavicollis, Apodemus sylvaticus, Microtus arvalis and Myodes glareolus). HEV was detected exclusively in Common voles (M. arvalis), in 10.2% of screened voles, and 3.2% of all investigated samples from all species. Based on the phylogenetic analysis, our strain showed the closest homology with European Orthohepevirus C strains detected previously in faecal samples of birds of prey and Red fox, supporting the possibility of the dietary origin of these strains. In addition, our samples showed close phylogenetic relation with a South American strain detected in Necromys lasiurus (Cricetidae), but separated clearly from other Muridae‐associated strains, suggesting the presence of a Cricetidae‐specific genotype in Europe and South‐America. Based on these results, we hypothesize the reservoir role of M. arvalis rodents for the European Cricetidae‐specific Orthohepevirus C genotype.  相似文献   
84.
The aim of this study was to optimize the conditions for hypothermic storage of spermatogonial stem cells (SSCs) and oogonial stem cells (OSCs) of common carp Cyprinus carpio. This was conducted by storing gonadal tissue or isolated cells for 24 hr under hypothermic conditions in the first experiment and by testing two different storage media (L‐15 or DMEM supplemented with 10% FBS and 25 mM HEPES) and regular medium change (every 4 days) during two weeks of hypothermic storage in the second experiment. During the first 24 hr, isolated cells showed no decrease in viability, while cells obtained from hypothermically stored tissues displayed significantly lower viability after only 6 hr (Tukey's HSD, p < 0.01) indicating that hypothermic storage of isolated cells is superior to storing tissue pieces. The 2‐week trial demonstrated that storage media have a profound influence, while regular medium exchange does not have a positive effect on cell viability. Viability of SSCs and OSCs after two weeks was approximately 40% and 25%, respectively; however, survival of ~70% was obtained after 10 days of storage for SSCs and 7 days for OSCs. Hypothermic storage developed in this study has many practical applications during the development of surrogate broodstock technologies for common carp, but also in carp hatcheries and for the conservation of genetic resources of closely related cyprinid species.  相似文献   
85.
Pheromones and attractants of click beetles: an overview   总被引:2,自引:1,他引:1  
The study of pheromones of click beetles was started with the objective of applying similar methods in IPM strategies for the control of wireworms, based on the similar experience gained from the widely used moth pheromones. A brief overview is presented on the identification of click beetle pheromones, new questions arising in the categorization of these pheromones into sex or aggregation pheromones, options for the development of female-targeted lures, and application perspectives.  相似文献   
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In the nature reserves of Bugac (Juniper stands) and Kunbaracs (Convallaria-oak-stands), both located in the Hungarian low land, the community of the Coleoptera moving on the soil were analyzed by help of cup shaped traps. In Bugac 40 species and in Kunbaracs21 species of Coleoptera were trapped. The very old Juniperusassociations of Bugac showed the highest constant values of the beetles. The number of beetle species increased parallel to the range of organization of the plant association in the direction to climax.  相似文献   
89.
Accuracy of culture for diagnosis of Tritrichomonas foetus was investigated in 2832 naturally exposed range beef bulls from 124 herds. Preputial fluid samples were inoculated into the culture medium, incubated at 37 degrees C, and daily examined. Diagnostic test was evaluated using Bayesian techniques to estimate sensitivity and specificity without a gold standard. Median posterior test sensitivity was 72.04% (95% probability interval: 58.07-86.38%) and specificity was 95.37% (95% probability interval: 94.07-96.65%). Low diagnostic test accuracy may have resulted from host and/or diagnostic test procedure related factors. Under natural range conditions, more accurate methods for T. foetus diagnostic and repeated preputial samplings of bulls may be necessary on trichomonosis control programs.  相似文献   
90.
The effect of free-range versus cage management system on corticosterone transfer into the eggs was studied in laying hens. Hungarian Yellow laying hens (age: 21 weeks, body weight: 2.0 +/- 0.5 kg) were divided into two groups in the spring: Group I, free-range keeping (n=15 layers, density: > 0.5 bird/m2) in outdoor runs, with continuous access to a commercial layer feed; Group II, hens kept in battery cages (n=17 layers, density: 2 birds/m2, natural light, continuous access to feed and water). Eggs were collected after a one-week adaptation period on days 2, 7 and 16. Corticosterone (CST) was extracted from homogenised egg samples using an ASE-200 Accelerated Solvent Extractor and then assayed by liquid chromatography linked with tandem mass spectrometry (LC-MS/MS) [Thermo Quest Surveyor high-performance liquid chromatography (HPLC) interfaced via Atmospheric Pressure Chemical Ionisation (APCI) ion source to Finnigan/Thermo Quest LCQ Deca MS/MS] using dexamethasone as internal standard with positive APCI ionisation. CST concentrations of whole eggs laid by free-range hens on days 2, 7 and 16 were 0.370 +/- 0.218, 0.259 +/- 0.066 and 0.915 +/- 0.745 ng x g(-1), respectively, while those of eggs laid by caged hens were 0.206 +/- 0.157, 0.223 +/- 0.165 and 0.184 +/- 0.110 ng x g(-1) at the above sampling times. It is concluded that in free-range laying hens the sharp changes of environmental weather conditions significantly increased the corticosterone content of eggs, while the environmentally controlled and closed battery cage management technology resulted in relatively uniform corticosterone concentrations in the whole eggs.  相似文献   
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