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841.
Donald L Neiffer Michele A Miller Martha Weber Mark Stetter Deidre K Fontenot P K Robbins Geoffrey W Pye 《Journal of zoo and wildlife medicine》2005,36(2):250-256
Standing sedation was provided for 14 clinical procedures in three African elephants (Loxodonta africana) managed by combined protected and modified-protected contact and trained through operant conditioning. An initial hand-injection of detomidine hydrochloride and butorphanol tartrate at a ratio of 1:1 on a microg:microg basis was administered intramuscularly, with a dosage range of 50-70 mg (12.9-19.7 microg/kg) for each drug. The initial injection resulted in adequate sedation for initiation and completion of eight procedures, whereas supplemental doses were required for the remaining procedures. The dosage range for the supplemental injections of each drug was 4.0-7.3 microg/kg. Initial effect was noted within 3.0-25 min (mean = 11.6 min, SD +/- 5.9 min), with maximal effect occurring at 25-30 min for those procedures not requiring supplementation. In all but one procedure, this effect was maintained until the end of the procedure, which ranged from 47 to 98 min (mean = 74.7 min, SD +/- 18.8 min). No cardiac or respiratory depression was appreciated. Recovery after administration of reversal agents was rapid and complete, ranging from 2 to 20 min (mean = 9.0 min, SD +/- 7.0 min). On the basis of the authors' experience, recommended dosage ranges for reversal agents would be intravenous yohimbine (73.4-98.5 microg/kg), intravenous naltrexone (48.9-98.5 microg/kg), and intramuscular naltrexone (73.4-98.5 microg/kg). Approximately one-third to one-half of the total naltrexone dose should be administered intravenously. Mild adverse side effects limited to the gastrointestinal tract were observed in association with five procedures including abdominal distention with or without transient anorexia. Administration of reversal agents, encouraging exercise and water consumption, and administration of flunixin meglumine were helpful in the resolution of signs. In addition to gastrointestinal signs, slight ataxia was observed before initiation of surgical stimulation during one procedure in which 19.7 microg/kg of each drug was administered. On the basis of the procedures that did not require supplementation to initiate treatment and taking into consideration the potential for ataxia at higher doses, a starting dosage range of 14.7-16.2 microg/kg of both detomidine and butorphanol in a ratio of 1:1 on a microg:microg basis administered i.m. simultaneously is recommended. 相似文献
842.
John C. Weber Mahamane Larwanou Tougiani A. Abasse Antoine Kalinganire 《Forest Ecology and Management》2008,256(4):585-592
Prosopis africana (Guill., Perrott. and Rich.) Taub. is important for farming and pastoralist communities in the West African Sahel. It provides a range of essential products (wood, fuel, food, fodder and medicines) and services (soil fertility improvement), and is one of many native tree species maintained in the traditional agroforesty system, known as the parkland. However, this and other valuable species are disappearing in many parts of the region due to over-exploitation and, perhaps, due to increasingly drier conditions in the region. A provenance/progeny test (275 families from 28 provenances in Burkina Faso and Niger) was established at one location in Niger to investigate geographic variation in the species. Mean annual rainfall decreases from south to north and from west to east in the seed collection area. Given these gradients, one would expect clinal variation in growth and survival of P. africana and other tree species that occur naturally in the region. Tree growth (height, number of primary branches, stem diameter at 20 cm and 1.3 m) and survival were analyzed at 11 years. Variation due to provenances was significant for growth variables and almost significant for survival. Variation due to families within provenances was not significant for any variable. Provenance means for growth and survival increased from the more humid to the drier parts of the sample region. The clines in growth and survival with regional rainfall patterns suggest that tree improvement and conservation programs should collect seeds from populations in the drier zones for planting and conservation in the West African Sahel. This may be particularly important when one considers the trend in global warming. 相似文献
843.
Elżbieta J. Bielińska Barbara Futa Aleksandra Ukalska-Jaruga Jerzy Weber Szymon Chmielewski Sylwia Wesołowska Agnieszka Mocek-Płóciniak Krzysztof Patkowski Lilla Mielnik 《Journal of Soils and Sediments》2018,18(8):2682-2691
Purpose
The aim of this study was to determine the mutual relations between polycyclic aromatic hydrocarbons (PAHs) originated from atmospheric emissions and enzymatic activity and humic substances in soils at differently urbanized area, on an example of the Lublin city, east Poland.Materials and methods
The chosen areas represented three differently urbanized environments: old tenement houses and modern residential blocks, mixture of different building and rural landscape, and typical rural environment with smallholding farms, respectively. On each of the urban, suburban, and rural areas, one representative plot was chosen on fallow lands classified as luvisol derived from loess. The soil samples were collected from the top 25 cm layer. The following properties were determined: pH, organic carbon, total nitrogen, humic and fulvic acids, PAHs content (14 PAHs from US EPA list), and the activities of the following enzymes: dehydrogenases, acid phosphatase, alkane phosphatase, protease, and urease.Results and discussion
Higher contents of organic C and total N were found in the rural soil samples. The share of humic acid was similar in all soils investigated, ranging from 19.38 to 25.27%, while fulvic acid values differ significantly between urban and rural areas. The urban soils indicated much lower share of fulvic acids (9.78–10.99%) than those of rural (29.02–29.32%). Consequently, the values of the CHA:CFA ratio of the urban soil were approximately two times higher than those of the rural soil. The results showed that both the rate of humification and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases in the soils increased in the following sequence: urban < suburban < rural.Conclusions
The results showed that an increase of PAHs in the urbanized areas affect other soil properties. The phenanthrene/anthracene and fluoranthene/pyrene ratios pointed to coal combustion as the principal source of PAHs in the investigated soils. The PAH content in the urbanized area inhibit humification processes in the soil and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases.844.
Bernd Weber Ernst A. Stadlbauer Elmar Schlich Sabrina Eichenauer Juergen Kern Diedrich Steffens 《植物养料与土壤学杂志》2014,177(1):84-90
Recycling of P is a common strategy in efficient use of P. The aims of our investigation were to study the P extractability of biochars produced by low temperature conversion and to determine the effect of soda application on low‐temperature conversion of organic compounds and the bioavailability of P to rye grass (Lolium perenne L., cv. Grazer). In this study canola cake, dried distillers grains with solubles, and meat‐and‐bone meal were converted to biochars with thermo‐chemical conversion at 400°C. The P availability was measured in terms of solubility in water, 2% citric, and 2% formic acid, and in a pot experiment with rye grass (Lolium perenne L.) which was cut three times. Application of 8% (w/w) soda to the process of thermo‐chemical conversion of canola cake, dried distillers grains with soluble and meat‐and‐bone meal resulted in an increase of water‐, 2% citric‐, and 2% formic‐acid‐extractable P in the biochars. In contrast to the application of soda, addition of 12% wood ash (w/w) to the conversion of dried distillers grains with solubles resulted in a lower increase of water‐soluble P in the corresponding biochar compared to processing biochar without additives. Addition of biochar P (100 mg P [kg soil]–1) to a Luvisol resulted in an increase of CAL‐extractable soil P. The P uptake of rye grass from biochars produced with the addition of soda was as effective as basic slag and MgNH4 phosphate fertilizers and even better than rock phosphate. 相似文献
845.
Schwekendiek A Spring O Heyerick A Pickel B Pitsch NT Peschke F de Keukeleire D Weber G 《Journal of agricultural and food chemistry》2007,55(17):7002-7009
Resveratrol, a well-known phytoalexin and antioxidant, is produced by the action of stilbene synthase (STS) in some plant species. Hop (Humulus lupulus L.) plants of the Tettnang variety were transformed with a gene encoding for STS from grapevine. Under the control of the constitutive 35S cauliflower mosaic virus promoter, expression of the transgene resulted in accumulation of resveratrol and high levels of its glycosylated derivatives in leaves and inflorescences. Piceid, the predominant derivative, reached a concentration of up to 560 microg/g of fresh weight (f.w.) in hop cones, whereas no stilbenes were detected in nontransformed controls (wild-type). In transgenic plants the amounts of alpha- and beta-acids, naringenin chalcone, and prenylated flavonoids did not change significantly when compared with nontransformed plants. Transgenic plants showed normal morphology and flower development as did the nontransformed controls. The results clearly show that in hop constitutive expression of sts interferes neither with plant development nor with the biosynthesis of secondary metabolites relevant for the brewing industry. Since resveratrol is a well-known phytoalexin and antioxidant, sts transgenic hop plants could display enhanced pathogen resistance against microbial pathogens, exhibit new beneficial properties for health, and open new venues for metabolic engineering. 相似文献
846.
High mortality in egg layers as a result of necrotic enteritis 总被引:1,自引:0,他引:1
A new facility was designed to hold 1.8 million birds in 10 houses; chickens were placed in five of the houses, and the remaining five houses were under construction when this outbreak occurred. An increase in mortality was reported in five houses; however, mortality in house 7 was quite high. Well-fleshed birds were suddenly found dead without a significant drop in egg production. The middle and distal intestines were distended with gas, congested, thin walled, atonic, and bluish or pale in color with sloughed mucosa in some places. Necrotic enteritis was diagnosed as the cause of increased mortality. The ingesta in the crop occasionally contained flies. The 4-wk mortality in house 7 was 6.55% with a loss of 10,898 chickens. The 4-wk mortality rate in the other houses ranged from 0.54% to 1.98%. The houses affected with necrotic enteritis were treated for coccidiosis with amprolium because low numbers of the oocysts were present in the intestinal specimens of some of the chickens. Household bleach was added to the water at a dilution of one part bleach to 1040 parts water to control bacterial contamination. The fly (Musca domestica) population was out of control. Clostridium perfringens was isolated from the alcohol-washed macerated flies caught from houses 4 and 7. Dead flies were often seen in the feed troughs. The chickens may possibly have had C. perfringens infection as a result of consumption of dead flies or their secretions/excretions. The alcohol-washed, macerated, clarified fly extract from the affected houses caused death in 11 inoculated mice and paralysis in one mouse. Similarly, illness and mortality were present in four mice inoculated with clarified intestinal contents. The bacterium isolated on anaerobic culture was identified as C. perfringens by polymerase chain reaction. The disease was brought under control after straw was added and mixed in with the litter. As a result, the litter temperature increased, causing a decrease in the fly population. This study suggests that flies in the poultry houses acted as mechanical transmitters of C. perfringens and that the development of necrotic enteritis was by ingestion of bacteria present in the flies and their secretions/excretions. 相似文献
847.
848.
Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献