Biotechnologies in Animal Agriculture

Question 1

Used to generate more embryos per flush/collection

Answer 1

superovulation

Question 2

Method for the propagation of superior females

Answer 2

embryo transfer

Question 3

2 benefits of freezing embryos

Answer 3

-can transfer them at a later time
- ability to ship embryos internationally

Question 4

What keeps recruited follicles alive?

Answer 4

FSH

Question 5

Examples of FSH analogs that can be given for superovulation

Answer 5

FSH-P
Folltropin
Super-ov
equine chorionic gonadotropin
human menopausal gonadotropin

Question 6

The goal for superovulation:

Answer 6

3 to 20 ovulations of viable oocytes

Question 7

What protects the embryo when it’s recovered during flushing and when it’s frozen?

Answer 7

zona pellucida

Question 8

Superovulation protocol

Answer 8

-donor female is in estrus, 9 days later give FSH
-give FSH in decreasing dosages 2x a day for 4 days
-day 11 give PGF2a
~day 13 animal displays estrus and AI
-AI multiple times between days 13 and 14 then wait 7 days before recovering embryo
-day 20 give PGF2a so no excess embryos are released

Question 9

Why must the recipient female be in the same stage of estrus as the donor female?

Answer 9

Because fertility drops when the uterine environment and stage of embryonic development are not synchronized

Question 10

Desired superovulation response

Answer 10

multiple CLs on ovaries

Question 11

How is nonsurgical embryo recovery performed?

Answer 11

• give epidural anesthetic to the animal (makes procedure less uncomfy-feeling)
  -uterus is filled with fluid and the drained
  -embryos are recovered from out flow

Question 12

Why is an epidural anesthetic given to an animal before flushing aside from limiting discomfort?

Answer 12

it relaxes the cervix, making it easier for the handler to perform the procedure

Question 13

expected range for bovine embryo transfer

Answer 13

0-30 embryos per flush

Question 14

What percentage of flushes yield no viable embryos?

Answer 14

25%

Question 15

expected average of transferable embryos per flush in bovine

Answer 15

5-6

Question 16

Pregnancy rates are higher following transfer from fresh or frozen embryos?

Answer 16

Fresh embryos (60%)
-frozen (40-50%)

Question 17

Superovulation is used to increase the number of recovered embryos.

Answer 17

True

Question 18

The best choice of a recipient female to receive a blastocyst-stage embryo during an embryo transfer would be one that is at ________________ of her cycle.

Answer 18

day 7

Question 19

Sexed semen is obtained by sorting sperm cells based on

Answer 19

DNA content

Question 20

Which of the following does not occur with cloned calves?

a. Low pregnancy rates

b. Abnormal placental development

c. Increased calving difficulties

d. Shortened gestation lengths

e. Increased fetal growth

Answer 20

d. shortened gestation lengths

Question 21

Embryos are collected and transferred during the _____________ stage of development

Answer 21

blastocyst

Question 22

In cattle, sexed semen is packaged with the same number of sperm cells per insemination dose as conventional semen.

Answer 22

False