Swine Flashcards
when does farrowing occur with periodic farrowing?
twice yearly
how old is a finisher pig?
up to 6 months
how large are piglets when they are weaned?
12-15 lbs
what type of breeders are sows?
nonseasonal polyestrous
how prevalent is artificial insemination?
90% of USA swine farms
how long does pregnancy last?
113-115 days
do nursing sows experience lactation anestrus?
yes
what is the weaning to estrus interval?
4-6 days
how many oocytes do sows ovulate each estrus?
15-30 oocytes
do swine have follicular waves?
no
how large are follicles in estrus?
7-12 mm
what happens during the follicular phase?
number of small and medium follicles decreases: leave roughly 20 follicles 7-10 mm in diameter which will go on to ovulate
what can be seen when a sow is in estrus?
standing heat: reflex immobility
redness of vulva with production of thick/whitish mucus
how long does the estrous cycle last?
18-24 days
mean 21 days
how long does estrus last?
depends on presence of boar
40-60 hours
can vary <24 hours and >96 hours
what is estrus duration affected by?
intensity of boar contact during estrus detection
stress
parity
weaning to estrus interval
when does the corpus lutea reach their final diameter?
one week after ovulation
how long is development of the corpus luteum and production of progesterone independent from luteinizing hormone production?
10-12 days after ovulation
when does PGF2alpha cause luteolysis?
day 15
does the corpus luteum last for the entire pregnancy?
yes
why does lactational anestrus occur?
luteinizing hormone suppression
what is the degree of luteinizing hormone suppression related to?
suckling intensity
negative energy balance
stress
what is the common boar to sow ratio for group/pen mating?
1:8
when should you mate sows with hand mating/observed mating?
24-hour intervals
how can you make sure to not over-use boars in hand mating/observed mating?
not more than once or twice a day
rest at least 24 hours after 5 consecutive breedings at 12 to 24 hour intervals
how often are boars collected for artificial insemination?
1-2x per week
what is the typical dose of semen for artificial insemination?
1.5-5 billion sperm diluted to a total volume of 80-100 ml
sows that don’t conceive after _______________ are usually culled
3 cycles
what is the expected conception rates from artificial insemination?
90%
when is the first insemination for artificial insemination?
12 hours after sow comes into standing heat
what is the classic approach to artificial insemination?
intra-cervical
___________________ rotating locks the catheter into the cervix
counterclockwise
which female swine are not cycling for estrus synchronization?
prepubertal gilts
lactating sows
what is used to induce/advance estrus in non-cycling gilts?
boar exposure
what will affect timing of onset of puberty?
boar exposure
number of animals in group: larger group makes sooner
when should gilts be exposed to boars?
150-170 days
how long should gilts be exposed to boars?
5-30 minutes each day
boar exposure will result in _________ gilts in heat in the next 28 days
> 70%
what does boar exposure result in an increase in (hormone)?
GnRH and therefore luteinizing hormone and estrogen
who is PG 600 injection used in to induce puberty?
185 lb and 5 months of age
how quickly and reliably does PG 600 induce estrus?
> 55% gilts
within 7 days from injection
when are the majority in heat after group weaning?
within 7 days
when does estrus occur after feeding altrenogest?
4-9 days after withdrawal
how can you induce abortion in sows?
prostaglandin injected in pregnant pigs 12-90 days after breeding
when does synchronous return to estrus occur after inducing abortion?
4-10 days later
how can you synchronize estrus with altrenogest (matrix)?
feed consecutively for 14 days
estrus occurs 4-9 days after withdrawal
only effective in prepubertal cyclic females
how can you diagnose pregnancy?
nonreturn to estrus
real-time ultrasonography, doppler ultrasonography
amplitude-depth ultrasound
when can amplitude-depth ultrasound be used for diagnosing pregnancy?
28-80 days gestation
when can you use transabdominal real-time ultrasonography (B-mode) to diagnose pregnancy?
21 days onward
when is milk present in reference to parturition?
6-12 hours before farrowing
what are the issues associated with over conditioned sows?
more fat in birth canal
overheat faster
do not eat as much lactation feed
do not have as much milk
why do impactions occur around farrowing?
feeding disruption
reduced movement
stress
what are the normal presentation of piglets in the birth canal?
cranial or caudal
front or back legs extended toward opening of vulva
what is a breach position?
caudal presentation with legs pointing cranially
how common is dystocia?
<=1%
what are the signs of dystocia?
discharge without straining
straining without progress
only 1-2 delivered and then nothing for 2+ hours
what are the common causes of dystocia?
uterine inertia
obstruction due to large fetus
malpresentation
hypocalcemia, ketosis: rare
what should you give for dystocia?
oxytocin 5-10 units IM if no obstruction
what can help with the extraction of large piglets in a dystocia?
head snare
why is induction of parturiton used?
program daytime deliveries
allows for supervised farrowing
can be used if sow goes over due date
gestation should not go over ______________
116 days
what can you use to induce parturiton?
prostaglandin
prostaglandin and oxytocin
what has the greatest single impact on reducing piglet mortality?
supervised farrowing
how is the prognosis of uterine prolapse?
poor for survival
how do multiple large cysts (luteal cysts) present?
acyclic: do not show heat
how do multiple small cysts (follicular cysts) present?
irregular cycles
abnormal heat
do not ovulate
infertile
what should the incidence of pseudopregnancy (not-in-pig-sows) be?
<3% incidence
what are the viral causes of pseudopregnancy?
parvovirus
pseudorabies
PRRS
what are the causes of pseudopregnancy?
pregnancy misdiagnosis?
viral infection
heat or social stress
what are abnormal discharges usually due to?
endometritis (most common)
vaginitis
cystitis/pyelonephritis
what are the signs of endometritis?
post-breeding vaginal discharge
embryonic death, recycling at 21-day intervals
inflamed endometrium to pus-filled uterus
what is the response to treatment of endometritis/vaginal discharge like?
poor
often culled
how can endometritis/vaginal discharge be controlled?
hygeine
when are gilts mated?
7-8 months
first, second, or third heat
what are the ovaries like in the luteal phase?
30-90, 1-2 mm follicles
30-50, 2-7 mm follicles
when does prostaglandin spike?
between days 12 and 16
how long is the follicular phase?
4-6 days
what is the time from onset of estrus to ovulation?
36-44 hours
how long is the luteal phase?
15-16 days
how long after the LH surge does ovulation occur?
44 +/- 3 hours after
what are the negatives of group/pen mating?
less profitable
inefficient use of boars
high frequency of ejaculation may lower fertility
some estral females not bred
when are sows inseminated with artificial insemination?
first 12 hours after come into standing heat
second 12 hours after first
should gilts be in the same pen as a boar when exposing them to advance estrus?
do not need to
physical contact is recommended
what does boar exposure result in in terms of hormones?
transient increase GnRH and therefore luteinizing hormone and estrogen
what does boar exposure and PG600 result in?
more gilts than 70% coming into heat in the nest 5-10 days
what does boar exposure result in in terms of gilts coming into heat?
70% come into heat in the next 28 days
when is single-fixed time AI ovugel protocol injected post weaning?
4 days post weaning
AI 24 hours later
what is ovugel?
triptorelin acetate
what does amplitude-depth ultrasound (A-mode) detect?
fluid: not pregnancy-specific
how are most gestation diets formulated?
4.5-5lb per day
what are the problems with under conditioned sows?
problems in coming into heat after parturition
do not have as much milk
if you use prostaglandin only, when will farrowing occur?
80% of sows will farrow in next 36 hours
if you use prostaglandin and oxytocin, when will farrowing occur?
around 12 hours
what with induction can reduce piglet weight?
early: more than 3 days early
what are the negatives of inducing farrowing?
may increase stillbirths if sows are not monitored closely
colostrum quality may be reduced
do single cysts have an impact on fertility?
no
how can you control pseudopregnancy?
ultrasound exam and recheck after day 35
what does weaning pigs at birth lead to?
longer weaning to estrus intervals
longer farrowing to re-mating interval
follicular cysts
reduced fertility due to low luteinizing hormone and estrogen levels and poor uterine involution
_______________ lactation is standard and should not be shortened
21-28 day
