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81.
82.
Keaton Schmidt Cindy Feng Tingxuan Wu Tanya Duke-Novakovski 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(9):961
Neonatal mortality rate (NMR) may be affected by maternal physical condition, anesthesia, and uterine incision or en-bloc neonate removal. The association of selected factors with number of dogs with dead puppies at hospital discharge was evaluated using 78 records. Data obtained at admittance for emergency cesarean section included: age, small or large body size, rectal temperature, packed cell volume, serum total protein, blood urea nitrogen, glucose, puppy in pelvic canal, and heart rate. Administration of opioids, propofol, alfaxalone, isoflurane, and sevoflurane, and anesthesia/surgical times and surgical technique were evaluated using Fisher’s exact tests. There were 238 live puppies and 38 dogs had 58 dead puppies; the NMR was 19.6%. Mortality was associated with puppy in the pelvic canal (P = 0.003) and duration of anesthesia > 80 minutes (P = 0.029). Age > 8 years (P = 0.054) and induction time to start of surgery > 30 minutes (P = 0.17) may be associated with mortality. Expedient cesarean section with obstructive dystocia and an induction time to start of surgery < 30 minutes are important for puppy survival. 相似文献
83.
O. Schmidt D. Dujesiefken H. Stobbe U. Moreth R. Kehr Th. Schröder 《Forest Pathology》2008,38(2):124-128
Bacteria were isolated from necrotic lesions on a horse chestnut tree (Aesculus hippocastanum) with bleeding canker in Hamburg, Germany. Sequencing of the rDNA-ITS region revealed great similarity to pathovars of Pseudomonas syringae. Pseudomonas syringae pv. aesculi was identified by sequence homology of the gyrase B gene. This is the first report of P. syringae pv. aesculi in Germany. Phytophthora was not detected. 相似文献
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Zusammenfassung Nach einem kurzen Überblick über die gesetzlichen Grundlagen für die Durchführung der Pflanzenbeschau wird über die Ergebnisse der Kontrollmaßnahmen bei der Einfuhr von Pflanzenerzeugnissen (Getreide) nach Berlin (West) berichtet. Von 1980 bis 1985 wurden insgesamt mehr als 700 000 Tonnen Weizen, Braugerste, Roggen, Hafer, Sonnenblumenkerne, Hirse und Erdnüsse aus 12 europäischen, amerikanischen und afrikanischen Ländern eingeführt, davon mehr als 99% allein aus der DDR.Die Importe aus der DDR waren im Durchschnitt zu knapp 1% mit Vorratsschädlingen befallen, und zwar mit dem Reiskäfer (Sitophilus oryzae L.), dem Gemeinen Kornkäfer (Sitophilus granarius L.), Leistenkopfplattkäfern (Cryptolestes spp.), dem Amerikanischen Reismehlkäfer (Tribolium confusum Duv.) und dem Rotbraunen Reismehlkäfer (Tribolium castaneum Hbst.).
Mit 2 Abbildungen und 3 Tabellen 相似文献
Stored products activities of the plant protection office Berlin. The inspection of imported stored products from 1980 to 1985
A brief survey is given about the legal basis for the inspection of stored products (cereals) imported to Berlin (West). This follows a report about the results of those controls. From 1980 to 1985 more than 700,000 tons of wheat, barley, reye, oats, sunflower seeds, millet and peanuts were imported from 12 European, American and African countries, more than 99% of them from the GDR.On average about 1% of the imports from the GDR were infested by stored product pests; there were rice weevil (Sitophilus oryzae L.), grain weevil (Sitophilus granarius L.), grain beetles (Cryptolestes spp.), confused flour beetle (Tribolium confusum Duv.) and red flour beetle (Tribolium castaneum Hbst.).
Mit 2 Abbildungen und 3 Tabellen 相似文献
89.
J.W. Lehmkuhler E.E.D. Felton D.A. Schmidt K.J. Bader H.E. Garrett M.S. Kerley 《Agroforestry Systems》2003,59(1):35-42
Silvopastoral systems offer an alternative to the conventional cow-calf segment of the beef industry in the Midwestern region
of the United States. Little information exists for transitioning from a conventional pasture-based beef operation to a silvopastoral
system utilizing multiple deciduous tree species. Nine pastures approximately 1 ha in size were established with a mixture
of cool-season grasses and legumes to investigate tree protection methods and cattle performance. Four tree species (Juglans nigra, Gleditsia triacanthos, Quercus rubra, & Carya illinoensis) were planted within six of these pastures. Three methods of protection were tested, and included a no protection control
(Con), foliar application of 0.20% denatonium benzoate (TreeGuard™), or a single strand of electrified poly-wire (EF) in each
of the two grazing years. Cattle damage to young trees was prominent during the two years for Con and TreeGuard™. EF offered
acceptable protection. Red oak trees suffered the highest degree of damage from livestock. Establishing trees within grazed
pastures did not hinder performance of beef cattle. Transitioning from conventional pastures to silvopastures can be accelerated
utilizing an electrified fencing system to prevent cattle damage.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
90.
Herb-layer diversity in deciduous forests: Raised by tree richness or beaten by beech? 总被引:3,自引:0,他引:3
Andreas Mlder Markus Bernhardt-Rmermann Wolfgang Schmidt 《Forest Ecology and Management》2008,256(3):272
Where natural production capacity permits, modern silvicultural management in Central Europe frequently aims at the development of mixed broadleaved stands, instead of pure European beech (Fagus sylvatica) stands. It is crucial to study the effects of these tree-layer diversity variations on herb-layer vegetation, since herb-layer vegetation contributes significantly to ecosystem functioning in forests. In Hainich National Park (Thuringia, Germany), we conducted observational research in deciduous stands to investigate whether herb-layer diversity was related to canopy-layer diversity, and to ascertain possible causal mechanisms. We found that herb-layer vegetation of deciduous forest stands rich in canopy species appeared to be more diverse than herb-layer vegetation of beech-dominated stands. We surmise that herbaceous understorey diversity was indirectly influenced by canopy tree species through the medium of the altered environmental factors soil pH and litter layer thickness. Apparently, lower beech proportion had a more profound effect than the number of secondary tree species. There were no correlations between herb-layer diversity and light transmissibility of the canopy layer, indicating that the light factor was not crucial for herb-layer diversity. At least for the Hainich research sites, our results indicated that small-scale light and soil heterogeneity is insignificant for herb-layer diversity. We found several herb-layer species whose occurrence was particularly correlated with tree-layer diversity and environmental factors. Remarkably, all species positively correlated with soil pH were important for the phytosociological classification of the research sites. Beech-dominated research sites showed high tree-layer volumes, whereas research sites with high tree-layer diversity tended to feature lower tree-layer volumes. These findings could be the result of differing former silvicultural systems and varying soil clay contents affecting tree species composition. In contrast, herb-layer biomass was positively correlated with tree-layer diversity. Herb-layer productivity might be promoted in more diverse research sites by increased nutrient supply and base saturation. It is also possible that greater beech proportion interfered with herb-layer productivity. However, herb-layer biomass was also positively correlated with herb-layer diversity. Hence, our study hints that positive diversity-functioning relationships might occur in the herb-layer of the deciduous forest under investigation. 相似文献