what is the path sperm takes from deposition to site of fertilization for natural mating
where does fertilization occur?
Ampullary- Isthmic junction AIJ
which male reproductive organ is analogous to the female ovary?
where are sperm cells produced in the male ?
what is cryptorchid?
at what temp should the testes be maintained?
4 degree celsius BELOW body temp
what are the 3 mechanisms for regulation of the testes?
1scrotum- tunica dartos muscle will contract when temp falls-skin wrinkles
2cremaster muscle- temp falls and muscle contracts - pulls testes closer to the body
3 pampiniform plexus- complex network of blood vessels that cool the blood entering the testes
seminal vesicles -knobby appearence
cluster of grapes
nutrients and buffereing
provides energy in seman
produces thin. watery fluid to cleanse the urethra before ejaculation . urine is highly detrimental to sperm
account for gel like portion of semen in boars
helps force semen from urethra at the time of ejaculaiton
what is the importance of oxytocin?
induces milk let down . released during parturition to cause uterine contractions to aid in fetal and placental expulsion. and pre cum
where is progesterone produced in the cow?
corpus luteum and placenta
characterstics and actions of estrogen?
responsible for sexual behavior during estrus
responsible for secondary sex characteristics at time of puberty
relaxes cervix and increased uterine motility during estrus
elevates secretory activty of entire reproductive tract
what hormone is responsible for maintaining pregnancy?
in cattle how is AI achieved?
advantages of AI
gentic improvment through increased use of superior sires
disease control especially sexually transmitted diseases
improved record keeping
eliminates need for bulls kept on farm
may be more economical than natural service
disadvantages of AI
time required for estrus detection
percent of cows in estrous during the breeding season
trained personal required
over use of inferior sires
what is the AM.PM rule?
universally accepted time for insemination. cows detected in estrus in the morning are bred that same afternoon, those found in the afternoon are bred the next morning.