BACKGROUND Models of between-farm transmission of pathogens have identified service vehicles and social groups as risk factors mediating the spread of infection. Because of high levels of economic organization in much of the poultry industry, we examined the importance of company affiliation, as distinct from social contacts, in a model of the potential spread of avian influenza among broiler p...

The four profitability measures recommended by the Farm Financial Standards Task Force have limitations for examining wealth creation. Non-farm corporations, by contrast, have started to use Economic Value Added (EVA) to measure wealth creation. EVA has some advantages over other financial ratios because it fully accounts for the resources used on the farm and it includes both realized and unre...

Excessive water is used by farm field in Tarim river basin, it is very important to deep study on the relation between area of farm field and natural vegetation in recent 50 years. Collecting and processing various decades of remote sensing data, and got area of farm field, grass, forest, town and non-serviceable field. These results indict that: Because of the high flow period between 1950 and...

The technique of the processor farm has become very widely used for paral-lelising applications, often being mentioned without reference to any source. The goal of this work has been to put together a complete and rigorous understanding of what the technique can be used for and what is needed in order to arrive at an eeciently farmed application. This paper consists of these two parts. We have ...

This contribution is based on the personal experiences of the author as a typical crop farmer in Holland in 1925-1991, as a researcher at the Dutch Institute of Agricultural Engineering (19541964), and as the Director of that Institute in the period 1964-1983. In essence, the 20th century developments in mechanized agriculture are considered from a historical perspective. The future of farm mec...

As the size of livestock farms in The Netherlands is on the increase for economic reasons, an important question is how disease introduction risks and risks of onward transmission scale with farm size (i.e. with the number of animals on the farm). Here we use the epidemic data of the 1997-1998 epidemic of Classical Swine Fever (CSF) Virus in The Netherlands to address this question for CSF risk...

Although no country to date has released a major genetically modified (GM) food grain crop, China is on the threshold of commercializing GM rice. This paper studies two of the four GM varieties that are now in farm-level preproduction trials, the last step before commercialization. Farm surveys of randomly selected farm households that are cultivating the insect-resistant GM rice varieties, wit...

To quantify the respiratory disease burden among agricultural workers, we examined the 1988-1998 National Center for Health Statistics (NCHS) "Multiple Cause of Death Data" and the 1988-1994 Third National Health and Nutrition Examination Survey data (NHANES III). Proportionate mortality ratios (PMRs) were determined for 11 respiratory conditions among 6 agricultural groups: crop farm workers, ...