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971.
Van Bressem M Waerebeek KV Jepson PD Raga JA Duignan PJ Nielsen O Di Beneditto AP Siciliano S Ramos R Kant W Peddemors V Kinoshita R Ross PS López-Fernandez A Evans K Crespo E Barrett T 《Veterinary microbiology》2001,81(4):287-304
Serum samples from 288 cetaceans representing 25 species and originating from 11 different countries were collected between 1995 and 1999 and examined for the presence of dolphin morbillivirus (DMV)-specific antibodies by an indirect ELISA (iELISA) (N = 267) or a plaque reduction assay (N = 21). A total of 35 odontocetes were seropositive: three harbour porpoises (Phocoena phocoena) and a common dolphin (Delphinus delphis) from the Northeastern (NE) Atlantic, a bottlenose dolphin (Tursiops truncatus) from Kent (England), three striped dolphins (Stenella coeruleoalba), two Risso's dolphins (Grampus griseus) and a bottlenose dolphin from the Mediterranean Sea, one common dolphin from the Southwest (SW) Indian Ocean, three Fraser's dolphins (Lagenodelphis hosei) from the SW Atlantic, 18 long-finned pilot whales (Globicephala melas) and a bottlenose dolphin from the SW Pacific as well as a captive bottlenose dolphin (Tursiops aduncus) originally from Taiwan. The presence of morbillivirus antibodies in 17 of these animals was further examined in other iELISAs and virus neutralization tests. Our results indicate that DMV infects cetaceans worldwide. This is the first report of DMV-seropositive animals from the SW Indian, SW Atlantic and West Pacific Oceans. Prevalence of DMV-seropositives was 85.7% in 21 pilot whales from the SW Pacific and both sexually mature and immature individuals were infected. This indicates that DMV is endemic in these animals. The same situation may occur among Fraser's dolphins from the SW Atlantic. The prevalence of DMV-seropositives was 5.26% and 5.36% in 19 common dolphins and 56 harbour porpoise from the NE Atlantic, respectively, and 18.75% in 16 striped dolphins from the Mediterranean. Prevalence varied significantly with sexual maturity in harbour porpoises and striped dolphins; all DMV-seropositives being mature animals. The prevalence of seropositive harbour porpoise and striped dolphins appeared to have decreased since previous studies. These data suggest that DMV is not endemic within these populations, that they are losing their humoral immunity against the virus and that they may be vulnerable to new epidemics. 相似文献
972.
Pulp and paper mills often burn wood waste to fuel their boilers. The ash from a Mississippi pulp mill boiler was evaluated for potential use as an amendment to peat moss-based greenhouse substrates for production of young tomato plants. Between 0 and 50% ash was added to a custom-blended peat moss-based substrate, and these were compared to a commercially available substrate without ash. Addition of ash increased substrate pH, conductivity (EC), bulk density and water holding capacity, while reducing airspace and average particle size. In general, tomato plants grown in 0–40% ash had similar growth indexes as plants grown in commercial substrate. Increasing amounts of ash decreased tomato shoot nitrogen (N), potassium (K), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) concentration, and increased concentrations of phosphorus (P), calcium (Ca), sulfur (S), and boron (B). These results indicate that pulp mill ash has the potential to be used as a substrate component for greenhouse container production of tomato. 相似文献
973.
Hard red spring wheat (Triticum aestivum L.) cultivars each respond differently to chloride fertilizer under field conditions. The objective of this research was to investigate cultivar-specific chloride responses under controlled environments. Plants were grown in sand culture ± additional chloride (±20 mM KCl) nutrient solutions for four weeks. Of cultivars given additional chloride, ‘Butte,’ ‘Sharp,’ ‘Ingot,’ ‘Oxen,’ ‘Forge,’ and ‘Ember’ had significantly greater shoot chloride uptake than ‘Marshall.’ In soil-grown plants given 0, 20, 80, or 160 mM KCl from planting to heading, seed number remained constant, while individual seed weight and total yield decreased at higher KCl treatment levels in ‘Butte.’ Individual seed weight remained constant, while seed number and total yield increased in ‘Marshall.’ It was concluded that chloride fertilizer response in ‘Marshall’ under field conditions may have been mediated by reduced chloride uptake, which in turn resulted in decreased chloride toxicity at higher-chloride soil fertility levels. 相似文献
974.
J J Evans P H Klesius P M Gilbert C A Shoemaker M A Al Sarawi J Landsberg R Duremdez A Al Marzouk S Al Zenki 《Journal of fish diseases》2002,25(9):505-513
Streptococcus agalactiae was isolated from cultured gilthead seabream, Sparus auratus L., and diseased wild Klunzinger's mullet, Liza klunzingeri (Day), in Kuwait Bay, Arabian Gulf. Isolates were catalase negative, β‐haemolytic, Gram‐positive cocci and serogroup B. Experimental infectivity trials with mullet and seabream brain isolates in Nile tilapia, Oreochromis niloticus L., caused 100 and 90% mortality, respectively, within 7 days post‐inoculation indicating virulent S. agalactiae as the bacterial pathogen responsible for the epizootic in Kuwait Bay. 相似文献
975.
Alexander M. Evans 《Journal of Sustainable Forestry》2013,32(3):223-240
ABSTRACT The hemlock woolly adelgid (HWA, Adelges tsugae Annand) an invasive exotic insect, may extirpate eastern hemlock (Tsuga canadensis (L.) Carrière) trees from native forests, but other hemlock species could be planted to occupy their ecological niche. This study tests two of the most likely replacement species candidates: western hemlock (T. heterophylla (Raf.) Sargent) and Chinese hemlock (T. chinensis (Franchet) Pritzel). Low survival rates, slow growth, and infestation by HWA of western hemlock in eastern hemlock forests shows that the western hemlock is not a likely candidate for planting in the northern portion of eastern hemlock's range. In contrast, Chinese hemlock grew at rates similar to eastern hemlock and did not show any signs of HWA infestation. In this study, damage from deer was a much bigger problem than growth reductions from HWA. 相似文献
977.
Wintering seaducks in Britian and Ireland: Populations,threats, conservation and research priorities
- 1. This paper provides a detailed review of the status and distribution of wintering seaducks (Scaup, Eider, Long-tailed Duck, Common Scoter, Velvet Scoter and Red-breasted Merganser) in Britain and Ireland. It is based on a literature review plus analysis of National Waterfowl Counts (NWC) and other data. A summary of current knowledge of wintering seaducks is provided together with information on threats to populations, conservation goals and research needs.
- 2. Each species is examined in turn, with the emphasis on aspects of the population, habitat use, current distribution, trends and history. Important areas for individual species are highlighted.
- 3. Overall, seaduck populations have changed considerably, those for Eider and Red-breasted Merganser having expanded greatly, whilst those for Scaup, Common and Velvet Scoter have declined during historical and/or recent times. The trend for Long-tailed Ducks is unclear. British population estimates are considered to be out of date and need to be revised. The premier areas for seaduck communities are highlighted, thus providing basic information for conservation action and future monitoring.
- 4. Seaduck populations are threatened in a number of ways and the main factors are discussed. Oil pollution and the actions of commercial fisheries are the most important current threats. Conservation goals are suggested. These include an urgent need to develop appropriate domestic legislation to facilitate the protection of seaduck populations. Such legislation is currently almost entirely lacking.
- 5. Some priorities for research, particularly for better population monitoring of seaducks in British and Irish waters, are provided. These include: alterations to the NWC scheme to allow the collation of opportunistic counts, made when the conditions are amenable for censusing seaducks; extension of the scheme into areas not currently surveyed (e.g. most parts of Ireland); and the establishment of intensive survey programmes to monitor seaducks in the key areas of Britain and Ireland. It is hoped that this paper will serve to stimulate interest and commitment from all who play a part in safeguarding our seaduck heritage.
978.
979.
980.
Xavier Portell Ophélie Sauzet María Balseiro-Romero Pascal Benard Rémi Cardinael Estelle Couradeau Dieudonné D. Danra Daniel L. Evans Ellen L. Fry Edith C. Hammer Danielle Mamba Luis Merino-Martín Carsten W. Mueller Marcos Paradelo Frédéric Rees Lorenzo M. W. Rossi Hannes Schmidt Laura S. Schnee Charlotte Védère Alix Vidal 《European Journal of Soil Science》2021,72(1):31-34