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991.
Tuberculosis infections caused by Mycobacterium (M.) pinnipedii in a South American sea lion, Bactrian camel, and Malayan tapirs kept in two zoological gardens spanning a time period of 5 years are reported. The zoos were linked by the transfer of one tapir. Conventional bacteriological and molecular methods were applied to detect the pathogen. Spoligotyping and MIRU/VNTR-typing performed to assess the genetic similarity revealed identical molecular characteristics of the isolates from all animals involved. Anti-tuberculosis antibodies were detected using ELISA and a recently developed serological rapid test. The study shows that: (i) using molecular methods, the assessment of the genetic relationship of infectious agents helps to confirm the routes of infection, and that (ii) immunological tests may help to detect tuberculosis infections ante mortem more reliably and early. This would prevent the transfer of tuberculosis by asymptomatic animals.  相似文献   
992.
Bulk-tank milk samples analysed in a Bovine Herpesvirus-1 (BHV-1) blocking ELISA are still in use in the Danish BHV-1 programme as a tool to classify dairy herds as BHV-1 infected or BHV-1 free herds. In this retrospective study, we used data from the Danish BHV-1 eradication campaign to evaluate performance characteristics of the BHV-1 blocking ELISA in 1039 BHV-1-seropositive and 502 repeatedly BHV-1-negative dairy herds using the results of blood testing of the individual animals as the true infection status. At a cut-off value of 30% blocking reaction, the herd-level relative sensitivity and relative specificity were 82 and 100%, respectively. The herd-level relative sensitivity depended on the within-herd prevalence of seropositive cows and the cut-off value in the assay, but not on the time interval (up to 90 days) between the collection of the bulk-tank milk sample and the individual serum samples. The BHV-1 blocking ELISA on bulk-tank milk could detect seropositive herds (few), with prevalence proportions as low as one seropositive cow out of 70 cows.  相似文献   
993.
Fish have become a popular experimental model and companion animal, and are also farmed and caught for food. Thus, surgical and invasive procedures in this animal group are common, and this review will focus on the anesthesia and analgesia of fish. A variety of anesthetic agents are commonly applied to fish via immersion. Correct dosing can result in effective anesthesia for acute procedures as well as loss of consciousness for surgical interventions. Dose and anesthetic agent vary between species of fish and are further confounded by a variety of physiological parameters (e.g., body weight, physiological stress) as well as environmental conditions (e.g., water temperature). Combination anesthesia, where 2 anesthetic agents are used, has been effective for fish but is not routinely used because of a lack of experimental validation. Analgesia is a relatively underexplored issue in regards to fish medicine. However, recent studies have investigated opioid agents, nonsteroidal antiinflammatory drugs, and local anesthetics to determine their efficacy in minimizing pain and discomfort. The opioid morphine and the local anesthetic lidocaine do have significant effectiveness in reducing pain-related responses in rainbow trout (Oncorhynchus mykiss). Studies aimed at developing reliable analgesic protocols should explore a wide range of analgesic drug classes in several fish species.  相似文献   
994.
In experiments with fattening pigs peas and lupines were used, both pealed and unpealed, in order to investigate the influence of native crude fibres on the true digestibility of nitrogen and the amino acids in pigs. The results of the experiments allow the conclusion that native crude fibres, as long as they remain in the normal range between 3 and 7% in the ration does not cause a depression in the true digestibility of nitrogen and the amino acids in the feeding of fattening pigs. Only the increased content of native crude fibres in the ration has a negative effect on true digestibility.  相似文献   
995.
The digestibility for crude protein, ether extract, crude fibre, ash and nitrogen-free extract were determined for palm kernel meal samples. The test diets, identified as DA, DB and DI, were formulated to contain 10%, 20% and 40% palm kernel meal, respectively. With the exception of crude fibre and crude protein the digestibility of the nutrients of the diets decreased significantly as the dietary fibre content increased.  相似文献   
996.
The aim of this study was to assess the diversity of thermotolerant Campylobacter spp. isolated from turkey flocks at six rearing farms 1-2 weeks prior to slaughter (360 faecal swab samples) and from 11 different stages at the slaughterhouse (636 caecal, environmental, neck skin and meat samples). A total of 121 Campylobacter isolates were identified to species level using a multiplex PCR assay and were typed by pulsed-field gel electrophoresis (PFGE) and flaA-short variable region (SVR) sequencing. All Campylobacter isolates were identified as Campylobacter jejuni. PFGE analysis with KpnI restriction enzyme resulted in 11 PFGE types (I-XI) and flaA SVR typing yielded in nine flaA-SVR alleles. The Campylobacter-positive turkey flocks A, C and E were colonized by a limited number of Campylobacter clones at the farm and slaughter. The present study confirms the traceability of flock-specific strains (PFGE types I, V and IX; flaA types 21, 36 and 161) from the farm along the entire processing line to meat cuts. It seems that stress factors such as high temperature of the defeathering water (54-56 °C), drying of the carcass skin during air chilling (24 h at 2 °C), and oxygen in the air could not eliminate Campylobacter completely. Campylobacter-negative flocks became contaminated during processing by the same subtypes of Campylobacter introduced into the slaughter house by preceeding positive flocks even if they were slaughtered on subsequent days. Proper and efficient cleaning and disinfection of slaughter and processing premises are needed to avoid cross-contamination, especially in countries with a low prevalence of Campylobacter spp. The majority of flaA SVR alleles displayed a distinct association with a specific PFGE type. However, a linear relationship for all strains among both typing methods could not be established. To specify genetic relatedness of strains, a combination of different genotyping methods, is needed.  相似文献   
997.
The knowledge on dynamics of soil microbial activity and its correlation to climate and vegetation is still poor but essential for predicting climatic changes scenarios. Seasonal dynamics of soil microbial activity and cell counts were studied along an arctic‐alpine altitudinal gradient. The gradient comprised 12 ridges from 1000 to 1600 m altitude. Soil samples were collected during March, May, July and September 2005. The effect of temperature, snow depth and vegetation, all of which changed with altitude, on soil microbial activity and bacterial cell counts was analysed. The potential activities of phosphatase and chitinase were determined using fluorescent 4‐methylumbelliferyl labelled analogues. Total and live bacterial cell counts were determined by live‐dead‐staining. We detected marked differences in soil microbial variables along the altitudinal gradient, forming three major clusters: a low alpine belt, a middle alpine belt, and an intermediate transition zone. Our results demonstrated that more frequent occurrence of shrubs and bryophytes would also increase microbial activity. Furthermore, we detected a clear relation (R2 = 0.6; P < 0.02) between high soil temperatures and greater soil microbial activity during summer. As higher temperatures are predicted to promote shrubs and higher humidity to promote bryophytes we expect microbial activity in dry heath tundra soils will increase with anticipated warmer, and in the case of Scandinavia, more humid climates. We did not find winter microbial activity to be less at snow‐free sites than at sites covered by snow up to depths of 30 cm; hence, possible future decreases in snow depth will not result in reduced winter microbial activity. We demonstrate that shrubs support winter microbial activity not only by trapping snow but also directly by increasing the amount of organic carbon.  相似文献   
998.
When calculating fertiliser recommendations and nutrient balances, growers and advisers usually do not do site specific measurements but use data from look up tables. Data given by older literature sources, however, do not take into account today's cropping practices. Therefore a databank on nutrient contents of total yields, marketable yields and harvest residues of 22 field vegetable crops is presented. This databank was compiled using results from topical field experiments and from recent literature.  相似文献   
999.
Winter nitrogen use in deciduous species is largely uncharacterized. We investigated nitrate uptake in the fine roots of a deciduous oak (Quercus serrata Thunb. ex. Murray). We conducted a 15N-labeling experiment using saplings of Q. serrata in the winter. During three weeks of labeled nitrate application, the concentration of 15N in the fine roots increased significantly. The amount of nitrogen absorbed, as nitrate, was 1.16 ± 1.02 mg N g DW−1, equivalent to 7.6 ± 5.8% of the total nitrogen content. Our results indicate that Q. serrata saplings have significant potential for nitrate uptake in the fine roots in midwinter (i.e., in the absence of leaves). Although a significant amount of nitrogen applied as nitrate was accumulated, nitrate concentration in the fine roots remained low during the labeling period. Furthermore, significant nitrate reductase activity was detected. These data suggest that Q. serrata saplings can assimilate nitrate in the fine roots in midwinter.  相似文献   
1000.
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