提高生产性能,降低用药成本

现代畜牧生产以其较高的遗传潜力而闻名,但由于动物的生命周期之中存在不同且复杂的挑战而往往导致无法获得较高的遗传潜力。本文介绍比利时Innovad公司生产的Lumance产品和Lumance Zn产品经证明是有效提高动物生产性能的产品。     

The spread of the fall armyworm Spodoptera frugiperda in Africa—What should be done next?

Journal of Plant Diseases and Protection - The following text summarizes the different perspectives of presenters participating in the section Plant Protection in the Tropics and Subtropics, 61st...     

Krebsartige Erkrankung an Pinus contorta-Herkünften

Canker in Pinus contorta provenances . In connection with canker of 9 Pinus contorta provenances the two discomycetous fungi, Crumenulopsis sororia and Lachnellularehmii, were identified. After artificial infections L. rehmii did not produce canker symptoms. Therefore only C. sororia is considered to be the primary parasite. The P. contorta provenances differed in their damage rate.     

A case study of forest management planning using a new heuristic algorithm

We present an approach to generate and evaluate different silvicultural development paths and to optimize the development of a Norway spruce stand, using a long-term planning horizon. To generate a silvicultural path, the maximum stand density was applied. At each thinning event, three possible thinning intensities (10, 20, 30% of the stem number per ha) were randomly chosen. A search algorithm known as modified Accelerated Simulated Annealing (mASA) was used to estimate the optimum combination of stand paths for a given forest as a whole. Production and economic management objectives were considered and then compared. The economic criterion was the Expected Stand Value (ESV) with a 4% discount rate. The generated data set of 38 Norway spruce stands (comprising a total of 123.8 ha) was used in the case study. The result with the best combination of paths was presented in a digitized forest map. Forest management simulation was performed using a specially developed computer program, for a planning horizon of 20 years. The mASA proved to be an effective search method for identifying optimum paths.     

Physiological studies on variation in resistance of Pinus sylvestris to Lophodermium pinastri

Buffering capacity and pH values of extracts of pine needles varied with age in the course of the ontogeny of needles. Significant differences between a resistant and a susceptible pine clone group in relation to resistance against Lophodermium pinastri could be shown in autumn and winter. Also the variability of the parasite influences the host-parasite interaction as shown by alteration of pH values by 3 L. pinastri strains in cultural trials on needle extract medium.     

Antimicrobial resistance of Staphylococcus aureus and coagulase negative staphylococci isolated from mastitis milk samples from sheep and goats

Staphylococcus aureus and coagulase negative staphylococci (CNS) were isolated from ovine and caprine mastitis milk samples originating from more than 40 Swiss farms. CNS dominated as causal microorganisms of mastitis in small ruminants. By restriction fragment length polymorphism (RFLP) analysis of the groEL gene and sequencing of 16S rDNA, various CNS species were identified, albeit certain of them predominated. For susceptibility testing of mastitis pathogens to selected antibiotics, minimal inhibitory concentrations were determined. Of the 67 S. aureus and 208 CNS strains, 31.3 % and 8.2 % were resistant to penicillin, 29.9 % and 1.0 % to ampicillin, 1.5 % and 10.6 % to erythromycin, and 3.0 % and 7.7 % to tetracycline, respectively. Moreover, 10 CNS strains (4.8 %) were resistant to oxacillin and one CNS strain to sulfamethoxazole/trimethoprim. The results obtained describe for the first time the resistance situation of mastitis pathogens from sheep and goats in Switzerland. However, accompanying and preventing measures are also of importance in mastitis control of small ruminants.     

Regional Sediment Deficits in the Dutch Lowlands: Implications for Long-Term Land-Use Options (8 pp)

Background, Aim and Scope   Coastal and river plains are the surfaces of depositional systems, to which sediment input is a parameter of key-importance. Their habitation and economic development usually requires protection with dikes, quays, etc., which are effective in retaining floods but have the side effect of retarding sedimentation in their hinterlands. The flood-protected Dutch lowlands (so-called dike-ring areas) have been sediment-starved for up to about a millennium. In addition to this, peat decomposition and soil compaction, brought about by land drainage, have caused significant land subsidence. Sediment deficiency, defined as the combined effect of sediment-starvation and drainage-induced volume losses, has already been substantial in this area, and it is expected to become urgent in view of the forecasted effects of climate change (sea-level rise, intensified precipitation and run-off). We therefore explore this deficiency, compare it with natural (Holocene) and current human sediment inputs, and discuss it in terms of long-term land-use options. Materials and Methods: We use available 3D geological models to define natural sediment inputs to our study area. Recent progress in large-scale modelling of peat oxidation and compaction enables us to address volume loss associated with these processes. Human sediment inputs are based on published minerals statistics. All results are given as first-order approximations. Results: The current sediment deficit in the diked lowlands of the Netherlands is estimated at 136 ± 67 million m3/a. About 85% of this volume is the hypothetical amount of sediment required to keep up with sea-level rise, and 15% is the effect of land drainage (peat decomposition and compaction). The average Holocene sediment input to our study area (based on a total of 145 km3) is ~14 million m3/a, and the maximum (millennium-averaged) input ~26 million m3/a. Historical sediment deficiency has resulted in an unused sediment accommodation space of about 13.3 km3. Net human input of sediment material currently amounts to ~23 million m3/a. Discussion: As sedimentary processes in the Dutch lowlands have been retarded, the depositional system's natural resilience to sea-level rise is low, and all that is left to cope is human countermeasure. Preserving some sort of status quo with water management solutions may reach its limits in the foreseeable future. The most viable long-term solutions therefore seem a combination of allowing for more water in open country (anything from flood-buffer zones to open water) and raising lands that are to be built up (enabling their lasting protection). As to the latter, doubling or tripling the use of filling sand in a planned and sustained effort may resolve up to one half of the Dutch sediment deficiency problems in about a century. Conclusions: Conclusions, Recommendations and Perspectives. We conclude that sediment deficiency – past, present and future – challenges the sustainable habitation of the Dutch lowlands. In order to explore possible solutions, we recommend the development of long-term scenarios for the changing lowland physiography, that include the effects of Global Change, compensation measures, costs and benefits, and the implications for long-term land-use options. Recommendations and Perspectives: -     

Influence of fertilization on acrylamide formation during frying of potatoes harvested in 2003

The quality of the potato has been found to vary, when grown under different agricultural and environmental conditions, such as the level of fertilization. Consequently these factors may influence the acrylamide formation during the preparation of French fries. These assumptions were studied on three varieties: Bintje, Ramos, and Saturna from the harvest of 2003. Decreasing N fertilization caused increases in the reducing sugar concentration from 60% up to 100% on DM for all varieties studied. Due to a high correlation between the reducing sugar content and the generation of acrylamide during frying, this resulted in a parallel increase in the acrylamide concentration of the French fries. Thus by lowering the amount of N fertilizer, an increase of 30-65% of the acrylamide generation during frying could be observed. It seems of extreme importance to find an appropriate balance between the level of N fertilizer in order to diminish acrylamide formation but on the other hand to obtain an acceptable tuber and to consider the environmental impact. All results reported should be seen in the perspective of the warm growing season of 2003.