Since 1957, selenium has found extensive use in livestock production to maintain an adequate selenium status in animals in areas of soil and feed/forage deficiency. Selenium may be given directly to livestock, or appl...Since 1957, selenium has found extensive use in livestock production to maintain an adequate selenium status in animals in areas of soil and feed/forage deficiency. Selenium may be given directly to livestock, or applied as a fertilizer amendment to increase selenium content of their feeds. This paper addresses the area of direct supplementation, which includes oral and parenteral supplementation, and with ruminant animals the use of slow-release boluses. Various chemical forms of selenium have been examined as supplemental sources, with sodium selenite being the earliest compound of choice. Comnbination of selenium supplementation with other livestock managernent practices led to use of selenium dioxide, which avoided solubility problems with selenite but produced effective responses. Barium salts have been used with some success as supplemental selenium sources. Experience with ruminal boluses has shown that high pressure pelleting of increased grain size selenium, in hollow pellets, has prolonged their useful life. Attention has been paid recently to residual selenium returned to the soil from livestock supplementation practices and the resulting opinion is that currently approved practices are acceptable from the point of view of environmental quality展开更多
In this paper, we begin with the swift changes in the knowledge economy time,analyze the implication of the agility, and consider the agile virtual enterprise as the mainorganizational form for the manufacturing enter...In this paper, we begin with the swift changes in the knowledge economy time,analyze the implication of the agility, and consider the agile virtual enterprise as the mainorganizational form for the manufacturing enterprises to realize agility. We classify the agilevirtual enterprises into products alliance style and knowledge alliance style, and compares theirmain features and profit distribution models. As a result, we give four basic structures for thebuilding and running of the agile virtual enterprises.展开更多
文摘Since 1957, selenium has found extensive use in livestock production to maintain an adequate selenium status in animals in areas of soil and feed/forage deficiency. Selenium may be given directly to livestock, or applied as a fertilizer amendment to increase selenium content of their feeds. This paper addresses the area of direct supplementation, which includes oral and parenteral supplementation, and with ruminant animals the use of slow-release boluses. Various chemical forms of selenium have been examined as supplemental sources, with sodium selenite being the earliest compound of choice. Comnbination of selenium supplementation with other livestock managernent practices led to use of selenium dioxide, which avoided solubility problems with selenite but produced effective responses. Barium salts have been used with some success as supplemental selenium sources. Experience with ruminal boluses has shown that high pressure pelleting of increased grain size selenium, in hollow pellets, has prolonged their useful life. Attention has been paid recently to residual selenium returned to the soil from livestock supplementation practices and the resulting opinion is that currently approved practices are acceptable from the point of view of environmental quality
文摘In this paper, we begin with the swift changes in the knowledge economy time,analyze the implication of the agility, and consider the agile virtual enterprise as the mainorganizational form for the manufacturing enterprises to realize agility. We classify the agilevirtual enterprises into products alliance style and knowledge alliance style, and compares theirmain features and profit distribution models. As a result, we give four basic structures for thebuilding and running of the agile virtual enterprises.
