Cyclicity Flashcards
what is the other well known reproductive cycle
menstrual cycle
what type of cycle do birds have
ovulatory cycle
birds have no pregnancy, so what does that lead to
no CL
if birds have no CL, what phases do they also not have
luteal phase
what is the only phase birds have
follicular phase
when will hens ovulate after oviposition
about 10-30 minutes after
how often are eggs typically oviposited
25-27 hours
oviposition
act of laying an egg
what represents the end of a hen’s cycle
once she lays an egg, then will start to repeat this process
about what time of day do hens oviposit
later each day
once egg is oviposited late in the afternoon
- no ovulation will occur
- hen will have skip day
clutch
pattern of egg laying from first oviposition through the pause day
young hen clutch has how many eggs
10-20
aged hen clutch has how many eggs
4-5
characteristics of young hens
- ovulate close to 10-minute mark
- oviposit eggs around 25 hours
characteristics of aged hens
- ovulate close to 30-minute mark
- oviposit eggs around 27 hours
season
several estrous cycles that occurring during a time period
polyestrus
many cycles
monoestrus
one cycle
anestrus
not cycling
what is predominant hormone elevated during estrus
estradiol
examples of polyestrus
cow
queen
pig
seasonal polyestrus long day
begins cycling as day length increases
examples of seasonal polyestrus long day
mare
seasonal polyestrus short day
begins cycling as day length decreases
examples of seasonal polyestrus short day
sheep
nanny
examples of monestrus
dog
wolf
fox
bear
reasons to why anestrus would occur
- pregnancy
- lactational
- stress
- seasonal
- pre pubertal
- inhibition of GnRH release
LH patterns before and after puberty
before: low
after: go up and down
with more fat, what is present in higher amounts
leptin
what is purberty actually based on
weight not age
more weight=
more leptin and puberty occurs quicker
melatonin
responsible for going back to hypothalamus and either stimulate or inhibit
what produces melatonin
pineal gland
in seasonal animals, does melatonin inhibit or stimulate
stimulates
when does LH go up for lactating cows
after weaning bc no more inhibition at hypothalamus from suckling calf
