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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 and taste the same. Thats 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 doesnt work in birds because eggs cant be removed and implanted, Instead, the company is trying to bulk-grow embryonic stem cells taken from fertilized eggs as soon as theyre laid. The trick is to culture the cells without them starting to distinguish, so they remain pluripotent, says Fitzgerald.
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.
41.Which statement is the best description of the new era of factory farming according to the first paragraph?
B. Thousands of eggs are produced every hour.
D. Identical eggs can be hatched on the production lines.
A. The USs National Institute of Science and Technology.
C. Embrex of North Carolina.
43. In the third paragraph, by saying Producers would like the same meat quantity but to use reduced inputs to get there. Mike Fitzgerald means that he wishes
B. chickens taste could be improved but at less costs.
D. chickens could grow to the same weight but with less feed.
A. Origen and Embrex will jointly invent machines to increase production.
C. Origen has joined hands with Embrex in producing cell-injecting machines.
45. The technology of freezing stem cells from different strains of chicken can do all the following EXCEPT that
B. Origen can supply all the strains of chicken the market might need.
D. chicken farmers can be supplied with whatever strain they need.