Flashcards in Reproduction Final Part 8 (Pozor) Deck (29):
Which chromosome is the sex chromosome in chickens? What about pigeons?
Chickens --> 5th
Pigeons --> 4th
In avian species, what are the chromosomal combinations for male and female?
Male --> ZZ
Female --> ZW
At what point in avian development is sex determined?
Describe the location of the testis in birds.
Dorsal to the caudal end of the lung and cranial margin to the kidney.
Describe the different colors that avian testes may be depending on species.
Cream --> most
Black --> cockatoos
Grey-green --> toucans
Describe the positioning of the avian epididymis on the testis.
T/F: Birds have NO male accessory sex glands.
How is mechanical sex achieved in birds?
Since males don't have penises, birds breed by cloacal touching.
Contrast determinate egg layers from indeterminate egg layers.
Determinate egg layers produce a fixed number of eggs no matter what. Indeterminate egg layers can increase their egg production to replace lost eggs.
Describe the avian ovary.
-Left side develops in most birds
-Caudal to lung
-Cranial to kidney
-Follicular development occurs early
-Juvenile: appears like a brain
-Mature: appears like tapioca
T/F: All animal species have a corpus luteum after ovulation.
Birds do not.
Name some key characteristics/events associated with the avian infundibulum.
-Fertilization occurs here
-Yolk membrane outer layer formed
-Sperm may sometimes be stored here
Name some key characteristics/events associated with the avian magnum.
-Where the majority of the albumin is deposited
Name some key characteristics/events associated with the avian isthmus.
-Calcification begins here
-Two shell membrane secreted
Name some key characteristics/events associated with the avian uterus.
-Addition of water and electrolytes into egg
-Calcification occurs and finishes
Name some key characteristics/events associated with the avian vagina.
-Houses sperm in sperm nests until ovulation
Describe hoe the geminal disc can be used to determine whether an egg is fertile or not.
Fertile --> disc is a blastoderm, looks like a doughnut
Infertile --> disc is a solid white spot
Male birds reach puberty (sooner/later) than female birds.
Male birds reach puberty LATER than female birds.
Describe some signs of avian pair bonding.
-Nest-seeking and building
-Can be done with owner in absence of suitable mate
Name an effect puberty has upon male birds.
It causes their testis to swell 500x their original size.
Describe the photoperiod of most birds.
Most birds --> long-day breeders
Emus --> short-day breeders
What is the effect of rainfall on tropical and desert species of birds?
It stimulates breeding behavior.
Which avian sex is generally first to obtain a suitable nesting site?
Describe the process of osteomyelosclerosis.
-Ossification of the marrow in long bones of the females.
-Occurs before egg laying
-Stimulated by androgens and estrogen
-May replace up to 75% of bone marrow
What happens to a hen's blood-calcium around the time of laying?
-Increased estrogen results in increased plasma calcium
-Serum calcium may be 20-30 mg/dL
Roughly how long does it take to pass an egg for the average chicken?
-Egg remains in uterus for 44 days
-Signs include: straining; decreased defecation; increased fecal volume, wide-based stance
Name some avians at risk of ovarian neoplasia. What about those at risk of testicular neoplasia?
Ovarian --> chicken, budgie
Testicular --> budgie