39- Clone Farm(lucrehuang)

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39. Clone Farm

Factory farming could soon enter a new era of mass production. Companies in the US are developing the technology needed to “clone” chickens on a massive scale. Once a chicken with desirable traits has been bred or genetically engineered, tens of thousands of eggs, which will hatch into identical copies, could roll off the production lines every hour. Billions of clones could be produced each year to supply chicken farms with birds that all grow at the same rate, have the same amount of meat a nd taste the same.

This, at least, is the vision of the US’s National Institute of Science and Technology, which has given Origen Therapeutics of Burlingame, California, and Embrex of North Carolina $4.7 million to help fund research. The prospect has alarmed animal welfare groups, who fear it could increase the suffering of farm birds.

That’s unlikely to put off the poultry industry, however, which wants disease resistant birds that grow faster on less food. “Producers would like the same meat quantity but to use reduced inputs to get there,” says Mike Fitzgerald of Origen. To meet this demand, Origen aims to “create an animal that is effectively a clone”, he says. Normal cloning doesn’t work in birds because eggs can’t be removed and implanted, Instead, the company is trying to bulk-grow embryonic stem cells taken from fertilized eggs as soon as they’re laid. “The trick is to culture the cells without them starting to distinguish, so they remain pluripotent,” says Fitzgerald.

Using a long-established technique, these donor cells will then be injected into the embryo of a freshly laid, fertilized recipient egg, forming a chick that is a “chimera”. Strictly speaking a chimera isn’t a clone, because it contains cells from both donor and recipient. But Fitzgerald says it will be enough if, say, 95 percent of a chicken’s body develops from donor cells. “In the poultry world, it doesn’t matter if it’s not 100 percent,” he says.

Another challenge for Origen is to scale up production. To do this, it has teamed up with Embrex, which produces machines that can inject vaccines into up to 50,000

eggs an hour. Embrex is now trying to modify the machines to locate the embryo and inject the cells into precisely the right spot without killing it.

In future, Origen imagines freezing stem cells from different strains of chicken. If orders come in for a particular strain, millions of eggs could be produced in months or even weeks. At present, maintaining all the varieties the market might call for is too expensive for breeders, and it takes years to bread enough chickens to produce the billions of eggs that farmers need.

1. Which statement is the best description of the new era of factory farming according to the first paragraph?

A. Eggs are all genetically engineered.

B. Thousands of eggs are produced every hour.

C. Cloned chickens are bulk-produced with the same growth rate, weight and taste.

D. Identical eggs can be hatched on the production lines.

2. Which institution has offered $4.7 million to fund the research?

A. The US’s N ational Institute of Science and Technology.

B. Origen therapeutics of Burlingame, California.

C. Embrex of North Carolina.

D. Animal welfare groups.

3. In the third paragraph, by saying “Producers would like the same meat quantity but to use reduced input s to get there.” Mike Fitzgerald means that he wishes

A. chickens’ quality could be maintained but with less investment.

B. chickens’ taste could be improved but at less costs.

C. chickens’ growth rate could be quickened but with less inputs.

D. chickens could grow to the same weight but with less feed.

4. Which of the following statements about Origen and Embrex is correct according to the fifth paragraph?

A. Origen and Embrex will jointly invent machines to increase production.

B. Origen wants to purchase an efficient donor cells injecting machine.

C. Origen has joined hands with Embrex in producing cell-injecting machines.

D. Origen is the leading company in producing embryo-locating machines.

5. The technology of freezing stem cells from different strains of chicken can do all the following EXCEPT that

A. farmers can order certain strains of chicken only.

B. Origen can supply all the strains of chicken the market might need.

C. chicken farmers order certain strains of chicken for economic reasons.

D. chicken farmers can be supplied with whatever strain they need.

答案与题解:

1. C第一段昀后一句提供了直接的答案。

2. A第二段共提到三个研究机构和一个民间组织。the US’s National Institute of Science and Technology为研究提供了经费,被资助的研究机构是Origen Therapeutics of Burlingame, California和Embrex of North Carolina。因此,A是答案。

3. D 原句的意思有两点是关键的,即每只鸡提供的肉量不变,但饲料(inputs)要减少,只有D符合原意。

4.C 该段第二句中which引导的从句表明,是Embrex生产疫苗注射装置,而不是两家研究单位共同研制。Embrex在此基础上将装置改造为细胞注射装置。所以,只有C昀接近原意。

5. A该段的大意是,如果能冷冻所有品种的鸡的干细胞,那么,无论需要什么品种的鸡蛋或多少数量,都不是问题。但是,目前储备所有品种是非常昂贵的。

B、C、D从几方面表达了这层意思。四此,只有A是答案。

注释:

1. on a massive scale:大规模

2. genetically engineered:经过基因改造。genetical engineering:遗传工程

3. hatch into identical copies:孵出如出一辙的(小)鸡

4. to help fund research:资助研究。fund用作动词,research是它的宾语。

5. put off:意为“discourage”(使…气馁)。

6. bulk-grow:大量繁殖

7. stem cells:干细胞

8. culture:动词,意思是“培育”。

9. a freshly laid, fertilized recipient egg:新产下的、己受精的、要接受细胞植入的鸡蛋

10. scale up:提高,按比例增加

11. team up with:与……合作

12. up to 50,000 eggs:多达5万只鸡蛋

13. different strains of chicken:不同品种的鸡

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