Reproduction Flashcards
What are the stages of the estrous cycle in order?
Proestrus (time leading to estrus), estrus (time of mating), diestrus (the time when pregnancy is being established.
What hormone causes the behaviors and sexual receptivity when a female is in estrus?
Estrogen
What is the act of giving birth called?
Parturition
What are the stages of parturition?
Stage I is the preparatory stage. Maternal pelvic ligaments relax and the cervix softens. The female becomes restless and prepares to give birth.
Stage II is the expulsion of the fetus.
Stage III is the expulsion of the placenta.
What physiological changes and behaviors do an intact female dog display during proestrus? What does vaginal cytology show?
The bitch is attractive to male dogs but will not allow mating. The vulva is swollen and a serosanguineous discharge is present. Rising estrogen levels causes epithelial cells in the vagina to cornify.
What is the length of the estrous cycle and gestation in dogs?
Estrous cycle - no true cycle. Estrus 2x per year
Gestation - 63 days
What is the length of the estrous cycle and gestation in cats?
Estrous cycle - seasonally polyestrous, depends on whether or not ovulation occurs. Induced ovulation.
Gestation - 65 days
What is the length of the estrous cycle and gestation in horses?
Estrous cycle - seasonally polyestrous, 21 days
Gestation - 330 days, variable
What is the length of the estrous cycle and gestation in cows?
Estrous cycle - 21 days
Gestation - 283 days
What is the length of the estrous cycle and gestation in goats?
Estrous cycle - seasonally polyestrous
Gestation - 150 days
What is the length of the estrous cycle and gestation in sheep?
Estrous cycle - seasonally polyestrous, 17 days
Gestation - 150 days
What is the length of the estrous cycle and gestation in pigs?
Estrous cycle - 21 days
Gestation - 114 days
What is the length of the estrous cycle and gestation in llamas?
Estrous cycle - induced ovulation
Gestation - 344 days
What is the length of the estrous cycle and gestation in alpacas?
Estrous cycle - induced ovulators
Gestation - 344 days
What physiological and behavioral changes occur in the female dog during estrus? What does vaginal cytology show?
Estrus is the period off receptivity when the birch will allow mating, During estrus, the vulvar swelling decreases slightly and the bloody discharge changes to a straw color, although a bloody discharge may continue through estrus. Vaginal cytology fully cornified and the background of the slide is clear. No white blood cells present.
What changes occur in vaginal cytology during the first day of diestrus in intact female dogs?
There is an abrupt decline in the percentage of cornified cells.
How many days after D1 (day 1 of diestrus) can you diagnose pregnancy in a dog via these methods: abdominal palpating, hormone assay, ultrasonography, and radiography?
Palpation - can be performed during a 7 to 10 day window beginning around day 21 after D1. After day 30, the ability to diagnose by palpation is lost unit late in gestation.
Hormone assay - 20 days post D1
Ultrasonography - approximately 20 days post D1, sometimes earlier, depending o machine and probe used
Radiography - 37 days post D1
How long does estrus last in cats? What are the behavioral signs associated with it?
It lasts 8 to 10 days. Signs include rolling and assuming an exaggerated lordosis when petted.
When can pregnancy be diagnosed in cats by these methods (how many days postcoitus): abdominal palpation, ultrasound and radiography?
Abdominal palpation - 16 to 30 days. Gestational sacs are too small before day 16 and too confident after day 30 to palpate.
Ultrasound - 14 days
Radiography - 43 days
What are the guild lines for recognizing distocia in dogs?
Strong, continual contractions for 30 minutes without progress. Weak, infrequent contractions for 2 hours without progress. Prolonged interval between puppies (no more than 2 hours should elapse between each delivery)
What are the guidelines for recognizing distocia in cats?
20 minutes of intense labor with no kitten, 10 minutes of intense labor when a kitten is present, acute depression, or the pretense of fresh blood for more than 10 minutes.
Under natural conditions in the northern hemisphere, when do mares cycle?
They begin cycling in late March or early April, and continue until September or October.
What behaviors does a mare exhibit during diestrus?
She teases “out”, resisting the stallion’s advances by kicking ,squealing, pinning her ears back and clamping her tail between her legs.
What behaviors does a mare exhibit during estrus?
She teases “in” by squatting, urinating, lifting her tail and “winking” (everting her clitoris) on the approach of the stallion.
When is pregnancy usually diagnosed in mares with the aid of ultrasonography? (time after ovulation)
2 weeks after ovulation
What virus is a significant cause of abortion in horses?
Equine herpesvirus. Mares should ideally be vaccinated against equine herpesvirus at 5, 7 and 9 months of gestation each time pregnancy occurs. Killed or modified live vaccines may be used.
What is a “red bag” during parturition in mares?
A red membrane (the chorioalantois) protrudes from the vulva, indicating premature placental separation. This is a emergency. the chorioalantois must be ruptured manually and delivery assisted or the foal will quickly die.
A retained placenta in mares for more than _____ hours duration needs veterinary attention.
6
How soon can pregnancy in cows be diagnosed via these methods: palpation per rectum, ultrasonography?
Palpation - as early as 30 days of gestation
Ultrasonography - 24 days or earlier in some cases
What 2 conditions are most commonly associated with uterine prolapse in cows?
Hypocalcemia and distocia.
How is vaginal prolapse in cows different from uterine prolapse?
Vaginal prolapse is a hereditary problem. Affected individuals should not be kept as breeding stock. Uterine prolapse is not hereditary and is not considered likely to recur.
What is milk fever in cows? How is it treated?
Parturition hypocalcemia. Characterized by flaccid paralysis. This is an emergency and should be treated by slow IV infusion of Ca gluconate or oral administration of a Ca-containing gel
What are the behavioral changes associated with sows in estrus?
If placed with a boar during estrus, a sow will engage in precopulatory behavior, the boar will initiate mounting attempts and eventually the sow allows him to mount. You can also check for lordosis by applying pressure on the pig’s back.
At what point during gestation is ultrasonography used to diagnose pregnancy in pigs?
Between 30 and 90 days of gestation
What are the 2 main diseases of the postpartum period in pigs?
Metritis is and mastitis.
When do estrous cycles start to occur in sheep and goats?
In the late summer and autumn. Sheep and goats are short-day breeders
What is the ram/buck effect?
The introduction of a new. Mature odoriferous male during the transition from the anestrus season into the breeding season will induce estrus in most female goats and sheep. This is due to male pheromones produced under androgenic stimulation
What methods are used to diagnose pregnancy in sheep and goats?
Checking for returning to estrus, ballottement (palpation) of the fetus in the abdomen and ultrasonography.
What is ringwomb?
The failure of the cervix to dilate during parturition in sheep and goats.
What are the symptoms and causes of pregnancy toxemia in sheep and goats?
Hypoglycemia may lead to neurological signs and in coordination. signal prolapse usually occurs late in gestation (3 to 6 weeks before parturition), and dystocia is like to result in a cesarean delivery. it is associated with multiple fetuses and inadequate nutrition.
True or False: pseudo pregnancy is common in goats.
True
