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1.
Stein T Martineau GP Morris R Charette R 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(6):355-362
It is proposed that just as the stethoscope and thermometer are fundamental tools for individual medicine, production and health recording systems are fundamental tools for effective population medicine. Treatment and control of clinical diseases as the primary objective is no longer considered appropriate for livestock population. Disease in populations now describes a deviation between what is happening and what is expected to happen. This redefinition of disease implies that it is of multifactorial origin and thus a different problem solving approach must be implemented. Therefore, a swine enterprise must be considered as a system, a set of interdependent components continuously interacting to produce pork. As a system, it is characterized by certain properties: change, environment, counterintuitive behavior, drift to low performance, interdependency, and organization. A redefinition of diseases implies also that they are not only “treated” but managed. Management consists of planning, monitoring, evaluation, and analysis. For this process to be implemented successfully, a goal-directed recording system providing a farm-based infrastructure for problem solving is essential. Clinical problem solving (diagnosis) is thus based on epidemiological and demographic methods. 相似文献
2.
The origin of the pair of common carotid arteries in the cat is inadequately described, and there are conflicting accounts in English veterinary anatomy textbooks published in the USA. We found one‐quarter of 40 adult domestic cats dissected had a bicarotid trunk (5 female, 5 male). When present, the bicarotid trunk arose from the brachiocephalic trunk approximately midway between the expected origins of the more frequently independently arising left and right common carotid arteries, and on average, it was 5.6 mm in length. Our findings make the incidence, topographical and measurement information available so that students and veterinarians can be aware of this not insignificant variation in branching of the major arteries, forming a bicarotid trunk, in the cranial mediastinum of domestic cats. 相似文献
3.
Stein JE Radecki SV Lappin MR 《Journal of the American Veterinary Medical Association》2003,222(11):1548-1551
OBJECTIVE: To assess efficacy of Giardia vaccination as a treatment for giardiasis in experimentally infected cats. DESIGN: Original study. ANIMALS: 16 young-adult cats. PROCEDURE: Cats were experimentally infected by orogastric administration of Giardia cysts. On weeks 4, 6, and 10, cats in the treatment group (n = 8) were given Giardia vaccine SC. For the first 28 weeks after infection, 3 fecal samples from each cat were examined weekly for Giardia cysts, and cyst numbers were counted. Fecal consistency was scored daily for the duration of the study. Results from vaccinated and unvaccinated cats were compared by logistic regression. RESULTS: All cats became infected and were shedding Giardia cysts by the end of week 2. Throughout the study, diarrhea was rare and was mild and transient when it did occur. By week 28, 5 of 8 vaccinated cats and 7 of 8 control cats had patent Giardia infections. Magnitude of infection, based on number of fecal samples with cysts and number of cysts per sample, decreased progressively in both groups over time. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of 3 doses of a Giardia vaccine did not completely eliminate the organism from experimentally infected cats in the study period. Since clinical signs were minimal in both groups of cats, it could not be determined whether vaccination lessened severity of clinical disease. Results may have been negatively influenced by the large inoculation dose. Whether Giardia vaccination is an effective treatment for giardiasis in naturally infected cats remains to be determined. 相似文献
4.
Harrus S Klement E Aroch I Stein T Bark H Lavy E Mazaki-Tovi M Baneth G 《The Veterinary record》2002,151(3):82-85
Forty-six cats with clinical haemobartonellosis were studied; 75 per cent of the cats of known age were two-and-a-half years old or younger, 50 per cent were intact males and 19.5 per cent were castrated males. The predominant signs of the disease were tachypnoea, lethargy, depression, anorexia, infestation with fleas, pale mucous membranes, icterus, emaciation, dehydration, splenomegaly, anaemia, leucocytosis, increased activities of alanine aminotransferase and aspartate aminotransferase, and azotaemia. Thirty-eight per cent of the cats that were tested for feline leukaemia virus (FeLV) antigen were positive, and 22 per cent of those tested for feline immunodeficiency virus (FIV) antibodies were positive. The prevalence of both FeLV and FIV was much higher than in the general Israeli cat population. The cats infected with both Haemobartonella felis and FeLV had a significantly lower body temperature, were more anaemic and the mean cell volume of their erythrocytes was greater than in the cats with haemobartonellosis alone. 相似文献
5.
Full-thickness canine cortical allografts were cleanly harvested, sterilized with ethylene oxide, and stored at room temperature. The allografts were incorporated into canine segmental femoral fracture repairs and compared clinically, radiographically, and morphologically with control femoral cortical autografts for function of the limb, graft acceptance, and bone union. Sterility was maintained and the cortical allografts were well accepted by the host animals, resulting in full use of the limb which was subjected to surgical operation. The allografts showed healing patterns similar to those of the autografts, as determined by radiographic, gross, and histologic evaluation of the proximal and distal host-graft interfaces. Evaluations were made monthly. The host-graft interfaces of the allografts and autograft were filled with woven bone with adjacent vascular invasion and remodeling of the graft at the final 4th-month evaluation. 相似文献
6.
Mass propagation of the German cockroach in refuse tips may result in an increased emigration of this species into the surrounding area of the tip and thus in a heavy infestation of nearby buildings. Therefore, knowledges about the migration behavior are important when refuse tips are managed or projected. The influence of several environmental factors (as sun, day time, wind, temperature, season, light intensity) on the running behavior of the German cockroach was investigated under outdoor conditions. The most important results are as follows:
- The reaction of young larvae (especially of L1 and L2) on the investigated factors differs considerably from that of older larvae and adults. As the young larvae do not emigrate, their behavior can be neglected in respect to the questions discussed here.
- During sunshine, the position of the sun is primarily responsible for the direction of the migration. The highest percentage of the cockroaches walks directly towards the sun or a few grade right and left from the sun. When the sun is covered by clouds, the variation in the running direction is very high and many cockroaches migrate even into the direction opposite to the sun.
- From morning to evening, the main migration direction is shifting from east to west, following the position of the sun.
- Wind direction (at speeds of less than 5 m/sec.) and temperature (within the activity range of the cockroaches from approximately 18 to more than 30°C) have no recognizable influence upon the migration direction.
- The clearest reaction of the running cockroaches towards the position of the sun was noticed during the main migration-time in the year (June and July).
- The results of these investigations confirm former findings made in the field during a mass emigration of the German cockroach from a refuse tip.
7.
W. Stein 《Journal of pest science》1961,34(6):87-89
Zusammenfassung Um den Einfluß verschiedener Insektizide und Fungizide auf Schlupfwespen der GattungTrichogramma zu prüfen, wurde deren Parasitierungsleistung bei Dauerkontakt mit dem betreffenden Mittel untersucht. Mit unbehandelten Apfelzweigen wurden solche verglichen, die mit den Fungiziden Dithane, Orthozid 50 und Ferbam F 40 bzw. den Insektiziden Ryania, Basudin R, Dipterex, Thiodan oder Metasystox gespritzt waren. Das Alter der Rückstände betrug 0, 24 bzw. 72 Stunden.Alle drei genannten Fungizide reduzierten die Parasitierung in den verschiedenen Varianten erheblich.Das spezifisch gegen Tortriziden wirkende Ryania zeigte praktisch keine toxische Wirkung. Die Anzahl der parasitierten Eier lag entweder gleich hoch wie bei den unbehandelten Kontrollen oder in einem Fall sogar erheblich höher.Die übrigen 4 Insektizide töteten die Schlupfwespen in kurzer Zeit ab, so daß in keinem Fall eine Parasitierung erzielt werden konnte.Noch nicht abgeschlossene Lebensdauerversuche bestätigen die erzielten Ergebnisse.Die Möglichkeiten und Probleme einer gemeinsamen Anwendung vonTrichogramma und Schädlingsbekämpfungsmitteln im Obstbau werden diskutiert.
Dem Leiter des Instiltutes für Biologische Schädlingsbekämpfung, Herrn ORR. Dr. J. Franz bin ich für wertvolle Hinweise und jederzeitige Hilfe dankbar. — Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Summary To examine the influence of various insecticides and fungicides upon egg-parasites of the genusTrichogramma, their efficiency of parasitization at permanent contact with the concerning pesticide was checked. With untreated applebranches were compared those ones, which were treated with the fungicides Dithane, Orthozid 50 or Ferbam F 40 and the insecticides Ryania, Basudin R, Dipterex, Thiodan or Metasystox resp.All three fungicides reduced the parasitization in the different variations considerably.Ryania, which shows a specific effect against tortricides, had no toxical influence on,Trichogramma.The other four insecticides killed the parasites within a short time, so that in no case a parasitization could be achieved.Investigations concerning the duration of life confirmed the result of the parasitization investigations.The possibilities and problems of a combined application ofTrichogramma and pesticides in apple orchards are discussed.
Dem Leiter des Instiltutes für Biologische Schädlingsbekämpfung, Herrn ORR. Dr. J. Franz bin ich für wertvolle Hinweise und jederzeitige Hilfe dankbar. — Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
8.
Andrius Kuliešis Stein M. Tomter Claude Vidal Adrian Lanz 《Annals of Forest Science》2016,73(4):857-869
Key message
Quality and reliability of forest resource assessments depend on the ability of national forest inventories (NFIs) to supply necessary and high-quality data. Over the last decades and especially since the 1990s, the NFIs in European countries have been rapidly developing. Possibilities for obtaining reliable and accurate data on annual increment from different inventory types were evaluated, and sample-based inventories have been found to be superior to standwise inventories in providing reliable data. Simplified methods may be employed when increment cannot be directly estimated from inventory data.Context
An increasing intensity of forest resource use requires more accurate, detailed and reliable information, not only on forest area and growing stock but also on forest stand productivity, wood increment and its components.Aims
The main objectives were to assess the capacities of forest inventories, the methods used for estimation of gross increment and its components and their accuracy and to demonstrate an effective method for estimation of increment when direct inventory methods are not available.Methods
Data about national forest inventory methods were obtained from 30 responses to a questionnaire, distributed amongst national correspondents of all European countries; reports of COST Actions E43 and FP 1001, databases of Temperate and Boreal Forest Resource Assessment (TBFRA) 2000 and State of Europe’s Forests (SoEF) 2011 were used as well. Analysis and comparison of results from different forest inventories were used for evaluation of data reliability. Relationships between growing stock and gross increment in European forests were also analysed, and corresponding models were proposed.Results
Seventy-nine percent of European forest area is covered by national forest inventories (NFIs) based on sampling methods and the rest on stand-level inventory and other inventory methods. Data obtained by aggregating standwise data usually underestimate growing stock by 15–20 % and gross increment even more. Almost half of the European forest area (47 %) is monitored using permanent plots, measured twice or more, allowing the estimation of gross increment and its components to be made directly.Conclusion
Implementation of NFIs based on sampling methods, especially with permanent plots, resulted in an improvement of data quality and in most cases an increase of growing stock and gross increment. The estimation of natural losses is the weakest link in today’s NFIs and in the current assessment of European forest resources. The proposed default values for gross increment and its components is an option to be used in countries not having NFI at all or those which have started it only recently.9.
Tree planting for poverty reduction in less-favoured areas of the Ethiopian highlands 总被引:1,自引:0,他引:1
This paper assesses the potential impact of planting of eucalypt trees as a strategy to reduce poverty in a less-favoured
area of the highlands of Ethiopia. Results from simulations with a bio-economic model for a less-favoured case study area
in the highlands are combined with survey data at community, household and plot level to assess how general the results of
the bio-economic model are. Application of the bio-economic model shows clearly that land degradation, population growth,
stagnant technology and drought threaten food security. Household welfare and land quality are deteriorating rapidly in the
area and interventions are urgently needed to avoid human disaster. Planting of eucalypts on land unsuitable for crop production
may substantially increase household incomes if market outlets for trees can be found. Tree planting will not have severe
negative effects on food production or land conservation. A policy combining promotion of tree planting and conservation of
cropland may achieve win-win benefits in terms of increased household incomes as well as more sustainable land-use. Analysis
of survey data from the Amhara Region of Ethiopia reveals that there is a large area of land that is unsuitable for crop production
located close to all-weather roads in the less-favoured areas of the region. Few trees have been planted on this type of land
up to now. The past policy seems to have discouraged tree planting except on homestead plots that are more suitable for food
crops.
This paper reports part of the IFPRI/ILRI project ‘Policies for Sustainable Land Management in the East African Highlands’.
These two agencies have provided funds and logistical support for the work. The Norwegian Ministry of Foreign Affairs has
provided funds for this research in the Amhara Region in Ethiopia. The authors also draw on earlier work funded by Research
Council of Norway. Any correspondence should be directed to the first author. 相似文献
10.
- 1. The purpose of this report is to determine the concentrations of tributyltin in sediments that would be protective against adverse effects on prey species of salmonids listed under the US Endangered Species Act.
- 2. Two approaches for determining adverse sediment concentrations due to tributyltin (TBT) contamination are presented here. The first is the equilibrium partitioning (EqP) approach, which relies on a sediment‐water partition coefficient and toxicological data for water exposures. The EqP approach utilizes the large water quality database that has been generated over the last two decades for TBT and provides strong evidence for adverse effects at low exposure concentrations.
- 3. The second approach involves determination of a TBT tissue residue that is considered harmful for most species, which is then used to predict the sediment concentration that would likely produce this adverse tissue concentration.
- 4. Both approaches are presented here because they generally support each other but based on the information presented below, and the inherent difficulty in measuring porewater concentrations, the tissue residue approach is the recommended method for determining adverse sediment concentrations.
- 5. Using this analysis, the protective sediment concentration for TBT proposed here is 6000 ng g?1organic carbon. Direct effects are not expected on salmonids at this sediment concentration because of their relatively short residence time in the estuary, general lack of interaction with sediment, and relatively high metabolic capacity. This concentration may ensure adequate abundance of salmonid prey species; however, it may not be low enough for the protection of sensitive benthic species.