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Flashcards in sex differentiation Deck (14):
1

What are the three key parts of reproductive development?

1. sexual determination (sex genetically decided)

2. Sexual differentiation (first physiological differences)

3. Sexual maturation (puberty)

2

What cells are responsible for forming the gonadal ridge formation?

Somatic Gonadal Precursor Cells (SGPCs)

3

.... germ cells (PGCs) migrate to site of .... development during embryogenesis

Primordial germ cells

gonad

4

PGCs are formed prior to ... in zebrafish and migrate toward ... cells

gastrulation

somatic gonad

5

PGCs divide mitotically then differentiate into ... or ...

oogonia

spermatogonia

6

What initiates PGCs migration to germinal ridge?

chemokine signaling

7

List three stock manipulations that improve farming efficiency 

-Compensate for environmental factors

-induce sterility (e.g. escapee fish)

-select for preferential sex (monosex culture)

8

What are some reasons to select for a preferential sex?

maximise growth

maximise growth phase

avoid reproductive precocity

even size distribution (reduce cannibalism, easier grading)

avoid reduction

isolate females for kavier production

9

name three advantages for monosex female production in salmon

grow faster

mature later 

produce eggs (caviar)

10

name two strategies to maintain a monosex culture

-manual sorting, by hand or mechanical grading

-hormonal sex reversal

(ideally, you would manipulate sex of broodstock so that all progeny are the desired sex)

11

Describe how hormonal sex reversal works

We want all-females(e.g. Salmon)

Create neo males (XX)  by treating regular females with androgens (egMT)

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12

What are two issues in the administration of sex hormones to developing fish during their critical period of sensitivity

-Requires precise knowledge of sex differentiation
–Highly species-specific (every fish is different)

13

Name three ways hormones can be delivered

-ingestion

-injection

-immersion

14

Name three hormones used for sex reversal to induce masculinisation (2) and feminisation (1)

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