Lecture 8 - Assisted reproduction in animals

Question 1

What is the extinction vortex?

Answer 1

Disease leads to smaller breeding populations which increases inbreeding which increases disease = extinction

Question 2

How can embryos be derived in agriculture?

Answer 2

In vivo - superovulated cows

In vitro - ovaries obtained from an abbatoir

Question 3

What is the benefit of just having sperm tubes?

Answer 3

Cost efficient

Question 4

How is the AI procedure performed?

Answer 4

Insemination into cervix/vagina - need to synchronise oestrous cycle

Question 5

How is oestrous cycle synchronised?

Answer 5

1. PGF(2a) - stops CL development and causes CL regression

2. Progesterone loaded device - loaded inserted into vagina and when it is removed the animal enters natural oestrous

Question 6

How do they sex sort sperm?

Answer 6

X sperm has more DNA therefore for has more fluoro

Question 7

What can FISH be used to look at?

Answer 7

Looks at the purity of the sample

Question 8

What are some problems with sex sorting?

Answer 8

• Exposes sperm to stress
• Freezing/thawing damage
• Desired sex ratio but decreased number of blastocyst

Question 9

What are the basic requirements for AI?

Answer 9

1. Semen - fresh or cryopreserved
2. Receptive female - natural or synthetic
3. Suitable equipment or personnel
4. Knowledge of reproductive anatomy of animal

Question 10

What is non-invasive hormone analysis?

Answer 10

Urine and faeces analysis

Question 11

How can we use contraception in wild species?

Answer 11

• Suppression of GnRH with vaccine
• Deslorelin - GnRH agonist
• Antibodies against porcine ZP to block fertilisation