问题 问答题 简答题

能引起鸡产蛋下降的疾病主要有哪些?

答案

参考答案:

主要有减蛋综合征(EDS-76)、鸡传染性支气管炎(IB)、产蛋鸡非典型新城疫(ND)、鸡肿头综合征(SHS)、禽流感(AI)、禽脑脊髓炎(AE)、禽痘(POX)、败血霉形体(MG)、传染性鼻炎(IC)和禽霍乱(FC)等。

阅读理解

We’ve talked about snails (蜗牛) and their slow move. But much of the time snails don’t move at all. They’re in their shells ---sleeping .

Hot sun will dry out a snail’s body. So at the least sign of hot sun, a snail draws its body into its shell and closes the opening with a thin cover. Then it goes to sleep. A snail will die in a heavy rain. So whenever it rains, it goes inside its shell house and goes to sleep. A snail can sleep for as long as it needs to. It can take a short sleep. Or it can sleep for days at a time. And it spends all the winter months in its shell, asleep.

In spring the snail wakes up. Its body, about three inches long, comes out of from the shell. When hungry, the snail looks for food. It can’t see very well. Its eyes, at the ends of the top feelers are very weak. But its sense of smell is very strong. It helps the snail to the new greens. Then the snail’s little mouth goes to work.

A snail’s mouth is no longer than the point of a pin(针). Yet it has 256,000 teeth! The teeth are so small that you can’t see them. But they do their work.. If you put a snail in a hard paper box, it will eat its way out. And if a snail wears out its teeth, it will grow new ones.

Mostly, a snail looks for food at night .But on cloudy days it eats in the daytime. It eats all day long. A snail can go on eating for hours and never feel full.

小题1:A snail__________.

A.moves more slowly in the daytime

B.has thousands of feet

C.doesn’t move at all

D.sleeps much of the time小题2:In the sentence “A snail draws its body into its shell” the word “draw” means_________.

A.to make with a pen

B.to keep away from

C.to pull

D.to move to end小题3:From the story we know_________.

A.the snail’s shell is very thin

B.a snail can’t see well

C.the snail’s nose is quite short

D.the snail’s body changes in different seasons小题4:A snail goes to sleep when_________.

A.it feels hungry

B.it is put in a paper box

C.spring is coming

D.it rains heavily小题5:Which of the following in not true?

A.A snail doesn’t like living under the sun.

B.In winter the snail doesn’t eat or move.

C.The snail’s teeth can’t be worn out..

D.The snail’s strong sense of smell helps to find things far away.

单项选择题 案例分析题