24 - Avian Mating Flashcards
Describe the avian mating process
Vas deferens ejects semen into cloaca
Folds of female cloaca swell during mating & allow semen transfer through cloacal contact
Female everts cloaca to make better contact with ejaculate
Less “courtship” behaviour - more forced copulation
Distribution of sexual activity of the rooster during the day
Active in morning and late evening
No matings at night
Active males often look scruffy, ‘rash’ on cloaca, dirty
If clean, cull?
Describe the decline of rooster/flock fertility? What age?
Natural relationship between bird behaviour and physiology; fertility declines with age
Rooster less interested/able to complete matings
Hen needs to be mated more to sustain fertility
Almost impossible to maintain early fertility in a +40 week old flock
What is a male/rooster spiking program? What does it do?**
Addition of 2% 28 week old males at 40-45 week flock age
What it does:
- reactivates/motivates older males
-young males will increase the overall mating freq of flock
- adds 3-6 chicks/hen to flock prod
- old male activity declines 6-9 weeks after spiking
Slide 9
Where are the sperm storage tubules? What do they do?
Located just inside the shell gland
Provide a micro-environment in which sperm can survive and retain fertility
Play a role in sperm selection
Sperm storage time in diff species
Japanese quail = 12 days
Chickens = 21-35 days
Turkeys = ~70 days
Why store sperm?
Ability to store sperm eliminates need to synchronize mating with ovulation
Reduced mating frequency (less susceptible to predators)
Fertility is extended in SST storage
How does sperm fertility diminish in the SSTs in chicken
~6 days they retain full fertilizing capacity
10 days = ~50% eggs are fertilized
19 days = ~15% eggs are fertilized
If you inseminate a chicken with 150 million sperm, what happens to most of them? How many reach SSTs?
Lose 84% in feces within 30 min
Up to 90% can’t pass through vagina
1-2% reach SSts
How does the interaction with the hen’s tract determine sperms fate
- Sperm selection starts with interaction with luminal fluids on way to SSTs
- Hen’s vagina have cilia that beat and move fluids and debris towards the cloaca (only most viable sperm can enter SSTs)
How do sperm enter SSTs? What is the microenvironment like?
Via motility and cilia action
Microenvironment:
- suppresses O2 uptake and motility (REST)
- inhibits enzyme systems
- stabilizes plasma membrane
of SSTs in chickens? Turkeys?
2000-3000 in chickens
20,000 in turkeys
Describe SST filling
- cilia located at entrance of SSTs, propel sperm into SST lumen
- 1d (chicken), 2d (turkey) to fill
- youngest and/or most “fit” sperm are selected and stored
Slides 18-22
Who’s your daddy experiment
SST selection of sperm (3)
- sperm w low motility are rejected (flushed out)
- recognition of sperm via proteins on sperm plasma membrane
- species-specific immunological barrier
