Lecture 13 Flashcards
How long is the ovulatory cycle in birds
Few hours
Does alternation between follicular and luteal phase occur in birds
No
What are the only functional things in a female reproductive tract
Left ovary and oviduct
How many preovulatory follicles are there
4-6
What happens to follicles at sexual maturation
Increase in diameter and establish a follicular hierarchy
Which follicle ovulates first
Largest
When does oviposition occur
24-26 hours after ovulation
What occurs at the infundiblium
Catches egg and is the site of fertilisation
What is the largest section of the oviduct
Magnum
What does magnum secrete
albumin protein
What is the shell gland
uterus - expanded section where shell is laid down
Why do chickens store sperm (2)
- Daily ovulatory cycle
2. No behavioural mechanisms to synchronise copulation with ovulation
What is the site of fertilisation in birds
Infundibulum
What rises before the onset of laying
Oestrogen
What increases before ovulation
Progesterone
What does progesterone in birds cause
Positive feedback on the hypothalamus that ultimately triggers the LH surge via GnRH
How long is egg in oviduct before being laid
24h
What is the function of progesterone (2)
- Induces LH surge
2. Controls albumin secretion
What is the function of oestrogen (2)
- Controls yolk protein synthesis by liver
2. Calcium redistribution from bones to the shell gland
What is the function of arginine vasotocin
From hypothalamus induces vaginal muscle contraction
What secretes androgens
ovary
What are androgens responsible for
Secondary sex characteristics (comb, wattle)
How often and long do birds moult
Once a year for a month
Where are testes in birds located
Intra-abdominal
