特别广播英语第 183 课：Sacrificed to Science? 为科学而献身-3

The test indicates toxicity. A method using a fixed amount, which gives the same eventual information but uses fewer animals and does not require that they die, may replace the LD50. 这个实验表明其毒性。一种用固定的数量可以得到相同的结论，但是使用较少动物而且不使它们死亡的方法可能代替LD50。

Many other new techniques are now available that enable more research to be done in the test tube to see if chemicals produce harmful biological effects. 现在已有许多其它的技术，可使更多的研究工作在试管中进行，从而发现化学药品是否产生有害的生物作用。

The number of animals used in laboratory tests has declined over the last 20 years. 过去的20年里，实验室里实验中使用的动物数量减少；

This is partly due to alternatives and partly to the fact that experiments are better designed so fewer need to be used - healthier animals provide better experimental results. 其部分原因是由于可供选择的方法多了，另外部分是由于实验设计得更好，因为使用更健康的动物能产生更好的实验结果，所以用的动物减少了。

For example, it used to take 36 monkeys to test a sample of polio vaccine, now it takes only 22. 例如，过去常用36只猴子来实验脊髓质炎疫苗样本，现在只用22只。

Also, lack of money has reduced the number of animals used - they are expensive to buy and expensive to keep. 缺少资料已使所使用的动物数量减少了――购买和使用动物都很昂贵。

Birmingham University now has Britain's first department of Biomedical Ethics. 伯明翰大学现在设有英国首家生物医学伦里学系。

Professor David Morton of the department is involved in animal research and is concerned with reducing animal suffering as much as possible. 系里的大卫·莫顿教授从事动物研究，并对尽可能地减少动物的痉很关心。

Animals spend 95% of their time in their cages and refinement also means making their lives better when not undergoing tests. 动物们在笼子里度过了他们95％的时间，改良也意味阒不进行实验时使它和得更好些。

This includes keeping them in more suitable cages, allowing social animals like dogs to live together and trying to reduce the boredom that these animals can experience. 这包括在更舒适的笼子里喂养它们，允许像狗那类喜欢合群的动物生活在一起，尽量减少这些动物可能经历的烦恼。