Bird repro Flashcards
Where are the testis found in birds?
Intraabdominal
Cranioventral to first kidney lobe, near abdominal air sac
When does spermatogenesis happen?
— better at cooler temp so happens at night when it is(cooler).
Where does the ductus deferens terminate in the bird?
Terminates in the urodeum on papilla
What is the variation of phallus amongst species in birds?
1.) No phallus, 2.)Phallus (but not used for intromission) and 3.) phallus (used for intromission).
1 and 2 used cloaca to cloaca contact to transfer semen.
What kind of erection do birds have?
Lymphatic and they have no accessory sex glands.
Which ovary is functional in the female reproductive tract?
The left. The right only functions if the left is damaged or removed.
What does each egg contain?
Single cell with lipid inclusion body (yolk)
What does each follicle contain?
Oocyte, granulosa cells, theca cells and yolk.
How do the follicles mature?
In a hiearchy.
What is the different function of theca and granulosa cells in birds compared to mammals?
In mammals granulosa cell produce estradiol and progesterone occurs after lutenisation in theca cells. However in birds the granulosa cells produce progesterone where it is converted to estradiol in theca cells.
What hormone is high during brooding?
Prolactin
What hormone is high just prior to egg laying?
Oestradiol.
What hormone is high during the egg laying period?
Progesterone.
What does oestrogen work to stimulate prior to egg laying?
Calcium ATPase, VLDL production in liver for yolk, oviduct enlargement, plumage and comb size to show receptivity.
As follicles mature what happens to theca cells?
enzyme activity decreases in theca cells and granulosa cells produce more progesterone for egg laying period.
What triggers ovulation in birds?
Progesterone.
Do birds form corpus luteums?
No there is not fetus to maintain as they lay eggs outside the body.
What is the function of the infundibulum in female birds?
It is ciliated columnar epithelium that captures ovulated
ovum. Fertilisation takes place in the infundibulum.
How long can sperm survive in the sperm storage tubules?
10-14 days meaning fertilisation can happen long after mating.
Give an overview of egg production?
. Infundibulum (<1 hr): chalazae added . Magnum (>3 hrs): albumen added . Isthmus (1 - 1 1/2 hrs): inner and outer shell membranes added . Uterus/shell gland (20 hrs): shell, cuticle, +1- pigment added . Vagina and cloaca (seconds - hours): oviposition
What is a pause day caused by in domestic hens?
In the domestic hen an Egg is laid 24-26 hours
after ovulation
The next Ovulation happens 15-75 min after
oviposition
Therefore each ovulation will occur just a little but
later each day
.This causes them to miss an open period and go a day without laying every now and then =“pause day”
What environmental factors can inhibit reproduction?
. They must have Access to nest box to prime repro activity. . Full access to mate Auditory < Auditory & Visual < Full Contact . Monogamous birds — need to form pair bond to breed. ‘ Photostimulation
Photosensitivity is important in reproduction behaviour. why?
Birds must be in a Photosensitive state to respond to daylight stages and short length daylight primes them. L#tW kIDOU . M Seasonal Influence: Daylight . Light exposure must be at critical times — First check at Dawn - Second check Photosensitive phase (13- 17 hrs after dawn)
A ZW would be?
Female
A ZZ would be?
Male
What are some methods for sexing birds?
. DNA (blood, feathers, eggshell) . Endoscopy . Fecal hormones . Instrument sexing . Vent sexing . Auto-sexing — Colour sexing (certain breeds males are diff colour silver male) — Feather sexing (female feathers longer)
