Midterm 3 - Lecture 26 Flashcards
How do chickens mate?
- vas deferens ejects semen into cloaca
- folds of female cloaca swell during mating and allow semen transfer through cloacal contact
- female everts cloaca to make better contact with ejaculate
- less “courtship” behaviour- more forced copulation
Do avians display courtship behaviours?
- not really; more forced copulation
What do sexually active male look like?
- scruffy
When are roosters most sexually active?
- at the beginning and especially end of the day
- assess mating behaviour at a time when males should be actively mating
What is fertility of the flock based on?
Activity of the roosters
When does rooster/flock fertility decline?
with age
How is rooster/flock fertility related to age?
- declines with age
- natural relationship btw bird behaviour and physiology
- rooster less interested and able to complete mating
- hen physiologically needs to be mated more often to sustain same level of fertility
How is a Rooster Spiking Program implemented?
- To keep fertility since it is almost impossible to maintain early fertility in a +40 wk old flock
- add 2% 28 wk old males to a flock at 40-45 wk of age
What does a Rooster Spiking Program achieve?
- reactivate/motivate older males
- young males will increase the overall mating frequency in the flock (second string)
- adds 3-6 chicks/hen to flock production
- old male activity declines 6-9 weeks after spiking
How is chicken and turkey breeding different?
Turkeys: AI
Chickens: natural breeding
What are 2 roles of the sperm storage tubules?
- Select sperm
- Store sperm
Where are the sperm storage tubules located? What do they do?
- located just inside the shell gland
- provide a micro-enviro in which sperm can survive and retain fertility
- play a role in sperm selection
Is sperm storage time different for different species?
yes
Why is sperm stored?
- ability to store sperm eliminates the need to synchronize mating with ovulation
- reduced mating frequency = less susceptible to predators
- fertility extended during SST
In chickens, how long is fertility extended during SST storage?
~6 days = full fertilizing capacity
10 days = ~50% eggs are fertilized
19 days = ~15% eggs are fertilized