时间:2019-01-30 作者:英语课 分类:农业与发展


英语课

AGRICULTURE REPORT

August 6, 2002: Caviar from California


By George Grow



Broadcast:


This is the VOA Special English AGRICULTURE REPORT.


The American state of California is famous for its agriculture. Now, scientists are working to make California a
world leader in the production of caviar. Caviar is made from the eggs of the large fish called sturgeon. Caviar is
a popular and very costly 1 food in many parts of the world.



The University of California at Davis reports that California is already the world’
s
leading producer of white sturgeon. It says the state’s success is partly the result of
work by one of its professors.


Serge Doroshov (surge DOOR-uh -shof) joined the university’


s animal science department twenty-five years ago. He and his


team showed that it is possible to speed up the rate at which


sturgeon develop sexually 2. To do this, they successfully
changed the environment where the fish develop. They also used hormones 3 to influence the
production of eggs and male reproductive fluid 4.


Sturgeon and their ancestors are thought to have lived as long ago as two-hundred-million
years. That is long before the appearance of most modern fish. Sturgeon have long, thin
bodies covered with a series of bony plates. The head is also well protected with these hard
structures.


Sturgeon can live for more than one-hundred years. Some weigh more than four-hundred-fifty kilograms.
However, the fish develop slowly. Females 5 in the wild are not able to reproduce 6 until they are fifteen to twenty-
five years old.


Most sturgeon move from salt water into inland waterways when they are ready to reproduce. However, some
live permanently 7 in fresh waters.


Sturgeon were once common in North America. However, too much fishing, building projects and pollution have
greatly reduced their number. Today, Iran and Russia produce most of the world’s caviar from sturgeon. The
most valuable caviar comes from a kind of sturgeon called beluga (ba-LOO-ga).


Professor Doroshov showed that sturgeon could be raised in small bodies of water and large containers. He also
showed that the fish will eat food not found in their natural environment. He and other scientists are now
attempting to grow bigger, longer-living sturgeon that produce large amounts of caviar.


Professor Doroshov has also helped develop methods to raise other kinds of fish.


This VOA Special English AGRICULTURE REPORT was written by George Grow.



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adj.昂贵的,价值高的,豪华的
  • It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
  • This dictionary is very useful,only it is a bit costly.这本词典很有用,左不过贵了些。
adv.性别上地;按性别地;性欲地;两性之间地
  • to be sexually promiscuous 性生活淫乱
  • I was depressed,withdrawn and sexually frigid. 我郁郁寡欢,离群索居,没有什么性要求。 来自《简明英汉词典》
n.流体,液体;adj.流体的,流动的
  • Fluid includes both gasses and liquids.流体包括气体和液体。
  • The weather is fluid in summer.夏天天气多变。
n.雌性动物( female的名词复数 );女人
  • The male birds are more colourful than the females. 这种鸟雄性比雌性更加色彩艳丽。
  • The males in the herd protect the females and the young. 兽中的雄性动物保护雌性动物和幼崽。 来自《简明英汉词典》
v.生育,繁殖,复制,重做
  • The machine can reproduce a key in two minutes.这机器能在两分钟内复制一把钥匙。
  • The picture will reproduce well.这照片会印得很清楚。
adv.永恒地,永久地,固定不变地
  • The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
  • The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。
学英语单词
-coel
adherers
amifloverine
antigen binding capacity
automatic oxygen safety valve
backwoods
baun
Bengi
biasing characteristic
billiard-ball
blowin
boronatrocalcite
burst cycle
buzz-stick method
caramelization
Certosa di Pesio
cexe
chauffe
Clairac
crants
demilancers
deoxygenated blood
dewatering shaker
eight-factor
elassogaster aerea
etract release volume
exprobrated
family bignoniaceaes
fangbian
feather picking
first-cycle
follicolous
foreign medium
got the show on the road
hand, foot, and mouth disease
headache powder
heathenizing
heavy concentration
heinze
hemato-
Hentiy Aymag
hyperthymism
iterative match
Kowanyama
large multangular bone (or trapezium)
long short story
made a mock of
maghan
magnetization
middle narial cavity
mine dangerous area
monotonic model
neuroneme
non-contact attemperator
non-indicating controller
null point
odontosarcoma
ordered access
over-note
parti colored buoy
Peale I.
perforated method
peroxocarbonate
phosphorescent detector
photo theodolite
photoengraving
photoinjector
pinkola
plunge feed shaving cutter
post stall
postlingual
press packs
professionals
put on foot
Ramsbottom coke test
red-backed sandpiper
religious text
ring piston servomotor
safe bind, safe find
sardinian (anglesite)
Schlieren mirror
second grouting
secondary principal stress
sin buffer
sparrow hawk
special loss
spontaneous elastic recovery
steere's liocichla
step tube
stress of fluid
Su-ao
surface insubmersibility
talcum powder
thick steel plate
tramsition period
undocumented alien
untucks
V&V (Verification and Validation)
weisglass
wicket-keepings
zelazny