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71.
72.
A co-culture assay for isolation of Borrelia burgdorferi sensu lato (sl.) from naturally infected ticks and dogs suspected of Lyme borreliosis (LB) was evaluated using buffalo-green-monkey (BGM) cells as the mammalian component. Four different media were tested for their ability to provide sufficient growth conditions for spirochetes and BGM cells. A total of 176 Ixodes ricinus ticks and 268 specimens from 98 dogs were used to compare cell-free culture with the BGM co-culture. A 1:1 mixture of Barbour-Stoenner-Kelly medium (BSK) and Eagle's minimum essential medium (EMEM) supported the growth of the two test strains, B. burgdorferi sensu stricto B31 and B. valaisiana VS116 to the same extent as BSK medium and the growth as well as the viability of BGM cells in this medium were the same as in EMEM. Using the 1:1 mixture of BSK and EMEM, borrelial growth measured in co-culture with BGM cells did not differ significantly from corresponding values obtained in cell-free cultures. In cell-free culture the isolation rate of B. burgdorferi sl. from ticks was significantly higher in BSK/EMEM 1:1 than in BSK medium (P < 0.01). Co-culture with BGM cells had no significant influence on the isolation rate of borreliae from ticks. However, a significant amount of isolates were obtained by one of the procedures only. Analysing canine specimens accordingly, spirochetes were grown from the blood of one dog after four weeks in BGM cell co-culture. The isolate was classified as B. afzelii by PCR-coupled restriction fragment length polymorphism analysis. 相似文献
73.
Genetic similarity of natural populations and plantations of Pinus roxburghii Sarg. in Nepal 总被引:1,自引:0,他引:1
Archana Gauli Oliver Gailing Valdir Marcos Stefenon Reiner Finkeldey 《Annals of Forest Science》2009,66(7):703-703
74.
Alicia L. Reiner Nicole M. Vaillant JoAnn Fites-Kaufman Scott N. Dailey 《Forest Ecology and Management》2009,258(11):2365-2372
Due to increases in tree density and hazardous fuel loading in Sierra Nevadan forests, land management is focusing on fuel reduction treatments to moderate the risk of catastrophic fires. Fuel treatments involving mechanical and prescribed fire methods can reduce surface as well as canopy fuel loads. Mastication is a mechanical method which shreds smaller trees and brush onto the surface fuel layer. Little data exist quantifying masticated fuel beds. Despite the paucity of data on masticated fuels, land managers desire fuel loading, potential fire behavior and fire effects such as tree mortality information for masticated areas. In this study we measured fuel characteristics before and after mastication and mastication plus prescribed burn treatments in a 25-year old ponderosa pine (Pinus ponderosa C. Lawson) plantation. In addition to surface fuel characteristics and tree data collection, bulk density samples were gathered for masticated material. Regressions were created predicting masticated fuel loading from masticated fuel bed depth. Total masticated fuel load prior to fire treatment ranged from 25.9 to 42.9 Mg ha−1, and the bulk density of masticated fuel was 125 kg m−3. Mastication treatment alone showed increases in most surface fuel loadings and decreases in canopy fuel loads. Masticated treatment in conjunction with prescribed burning reduced both surface and canopy fuel loads. Detailed information on fuel structure in masticated areas will allow for better predictions of fire behavior and fire effects for fire in masticated fuel types. Understanding potential fire behavior and fire effects associated with masticated fuels will allow managers to make decisions on the possibility of mastication to create fuel breaks or enhance forest health. 相似文献
75.
Sandra Rose-Meierhöfer Sabine Klaer Christian Ammon Reiner Brunsch Gundula Hoffmann 《Journal of Equine Veterinary Science》2010
Housing conditions do not frequently meet the natural needs of horses. German and Swiss studies have shown that merely 16% of horses are kept in group housing systems, but even these vary greatly with different effects on horses’ behavior. The objective of the survey was to determine whether horses show increased activity in barns with various options for movements and functional elements. Free movement stables allow horses to live within a herd, to decide whether to be outside or inside the herd, and to enable them fresh air supply. Data from 25 horses kept in three different open barns (O1–O3) were compared with that from two active barns with functional elements (active barn 1 and active barn 2), for example, automatic feeder, with five horses each. Activity-Lying-Temperature-pedometers fastened to a rear leg of each horse were used to measure activity. Animal data were recorded throughout a test period of 10 days per barn. The results showed a median of 46 to 68 mean daily activity impulses per 10 minutes for horses in stables O1 to O3. In stables active barn 1 to active barn 2, this measure was exceeded considerably with medians of 77 and 151. The activity impulses in the stable systems were significantly different at an error level of α = 0.05. These results support previous studies and show that activity of horses depends on their opportunities for moving. The sectioning of a stable, placement of functional elements, and feeding frequency have considerable effects on the activity level of the horse. It is useful to integrate different functional areas in a group housing system. 相似文献
76.
Somatic hybrids were produced by PEG-induced symmetric and asymmetric protoplast fusions in order to transfer resistance to
Alternaria brassicicola, A. brassicae, Phoma
lingam, Plasmodiophora brassicae and Turnip mosaic virus (TuMV) into Brassica oleracea var. capitata (cv. ‘Toskama’) and botrytis (cv. ‘Korso’). As resistance donors, ten species belonging to several genera of the family Brassicaceae including wild relatives
were used. Of 2,189 plants (somatic hybrids, partially in vitro cloned) tested, 1,616 (73.8%) were resistant against at least
one of the pathogens, indicating that, mostly, a successful resistance transfer has taken place. Five hundred and twenty-two
hybrids showed multiple resistances to two, three and, in a single case, to four pathogens. Irrespective of the donor parents
used in the fusion, a broad variability in symptom manifestation ranging from 0 (without symptoms) to 9 (highly susceptible)
could be observed. With regard to the Alternaria pathogens, Sinapis alba, B. nigra and B. juncea were the most effective resistance donors, whereas fusions with Raphanus sativus resulted in the most hybrids with resistance to clubroot and TuMV. As could be shown especially in asymmetric fusions with
S.
alba, Barbarea vulgaris and Hesperis
matronalis, transferred resistance to a pathogen may not correspond with resistance exhibited by the donor parent. Some combinations
in which both parents were highly susceptible, e.g. R. sativus (+) B. oleracea var. capitata, yielded hybrids that exhibited strong resistance, e.g. to A. brassicicola, revealing that a new type of resistance might be occurring. With regard to the Alternaria pathogens, resistance expression was very unstable. Many hybrids into which (also variable) resistance of some donors, such
as B. vulgaris, S. alba and B. carinata, was transferred became as highly susceptible as those of which the fusion parents did not show any resistance reaction (e.g.
R. sativus). For reliable characterization of the resistance response, hybrids should be subjected to several resistance tests during
growth period of the host, at least until flowering. 相似文献
77.
78.
Effect of dietary fish oil on the expression of genes involved in lipid metabolism in liver and skeletal muscle of lactating sows 下载免费PDF全文
D. K. Gessner B. Gröne S. Rosenbaum E. Most S. Hillen S. Becker G. Erhardt G. Reiner K. Eder 《Journal of animal physiology and animal nutrition》2016,100(2):337-347
This study investigated the hypothesis that dietary supplementation of fish oil as a source of n‐3 polyunsaturated fatty acids (PUFA) influences the expression of target genes of sterol regulatory element‐binding proteins (SREBP)‐1 and (SREBP)‐2 involved in triacylglycerol (TAG) synthesis and fatty acid and cholesterol metabolism in the liver, and moreover activates the expression of target genes of peroxisome proliferation‐activated receptor (PPAR)‐α involved in TAG and fatty acid catabolism in liver and skeletal muscle. Twenty lactating sows were fed a control diet or a fish oil diet with either 50 g of a mixture of palm oil and soya bean oil (4:1, w/w) or fish oil per kg. The diet of the fish oil group contained 19.1 g of n‐3 PUFA (mainly 20:5 n‐3 and 22:6 n‐3) per 100 g of total fatty acids, while the diet of the control group contained 2.4 g of n‐3 PUFA (mainly 18:3 n‐3) per 100 g of total fatty acids. The fish oil group had reduced relative mRNA concentrations of various target genes of SREBP‐1 involved in fatty acid and TAG synthesis in comparison with the control group (p < 0.05). Relative mRNA concentrations of target genes of PPARα involved in fatty acid catabolism in both liver and muscle, and mRNA concentrations of target genes of SREBP‐2 involved in cholesterol synthesis and uptake were not influenced by fish oil supplementation. Concentrations of cholesterol and TAG in plasma, fat content of milk and weight gains of litters during the suckling period were not different between the two groups of sows. In conclusion, this study suggests that fish oil has only minor effects on hepatic lipid metabolism, which are non‐critical with respect to milk production in sows. 相似文献
79.
Contents Fifty thoroughbred mares, located at Central-Southern Brazil near Sao Paulo (13 anestrous maiden, 18 anestrous barren mares and 19 postpartum mares) were treated with one to three injections, 48 hrs apart, of 2 mg of the novel PGF analog K 11941*, during the early part of the breeding season. Early season anestrus in these problem mares was compounded by the adverse effects of a drought. Plasma progesterone determinations revealed unexpectedly elevated plasma progesterone levels in 61.5% of the maiden mares, in 77.8% of the barren mares and in 68.4% of the postpartum mares (20 to 25 days postpartum). Treatments with K 11941 initiated luteolysis, heat and ovulations in 91.4, 45.5 an 63.3% of these mares, respectively, but initiated also heat and ovulation in 13% and 33% of mares with baseline progesterone levels. Treatments initiated covert and overt cyclic functions in 17 and 12 of those animals which did not conceive immediately. Fifteen animals with recurrent anestrus received further treatment with K 11941. Ten mares cycling silently were force bred when palpations indicated ovulatory follicles, and 7 conceived. Of the 50 mares treated, 38 became pregnant (76%: maiden mares: 76.9%; barren mares: 77.8% and postpartum mares: 73.7%) with breeding indices of 1.9, 1.36 und 1.57, respectively; and 37 mares gave birth to a live foal (74%), At the same stud, 138 control mares had a foaling rate of 82.6%. 相似文献
80.
Laura Plieschke Christian Edel Eduardo C. G. Pimentel Reiner Emmerling Jörn Bennewitz Kay‐Uwe Götz 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(4):286-292
Genotyping females and including them into the reference set for genomic predictions in dairy cattle is considered to provide gains in reliabilities of estimated breeding values for selection candidates. This should especially be true for low heritability traits. By the use of simulation, we extended a genomic reference set for an existing trait by including a fixed number of genotyped first‐crop daughters for one or two generations of reference sires. Moreover, we calculated results for the effects of a similar strategy in a situation where for a new trait the recording of phenotypes has recently started. For this case, we compared the effect of two different genotyping strategies: first, to phenotype cows but to genotype their sires only, and second, to collect phenotypes and genotypes on the same cows. We studied the effects on validation reliabilities and unbiasedness of predicted values for selection candidates. We found that by extending the reference set with genotyped daughters it is possible to increase the validation reliability of genomic breeding values. In the case of a new trait, it is always better to collect and use genotypes and phenotypes on the same animals instead of using only sire genotypes. We found that the benefits that can be achieved are sensitive to the sampling strategy used when selecting females for genotyping. 相似文献