Swine Breeding Management Flashcards
main goals of swine reproduction (3)
- Maximize the number of weaned pigs per sow per year (pigs/sow/yr)
- Be sure that the sows in the gestation barn are pregnant (Minimize non-productive sow days
(NPD)) - Consistent flow of pigs (economics of predictable flow)
what are the goals of herd performance (2)
- Max pigs born (or weaned) per sow/yr
- Min number of sow non-productive days (NPD)
what are productive vs non productive sow days and what does that mean in terms of non productive sow days
- Productive sow: pregnant or lactating
- Non-productive sow: open and not lactating
Therefore: Non-productive sow days = # days sow is not lactating and not pregnant per year
-> Weaning to conception/breeding interval
-> Unrecognized pregnancy loss or NIP
what two things are fixed with cows vs where can we adjust NPD
- Gestation days fixed biologically (114-116 days)
- Lactation days is “fixed” based on herd management (21-28 days)
- NPD are those days between weaning and conception
as number of NPD ____, then the number of litters per year will ____
increases, decrease
what will happen if you wean prior to 14 days? (5)
- reduce ovulation
- cause longer wean-breed interval
- predispose to cystic ovaries
- lower farrowing rate
- reduce the number of pigs born alive
primary signs of estrus (3)
- Standing while another sow or
boar mounts - Standing in the presence of the
boar - Back pressure test
secondary signs of estrus (13)
- Bar biting, climbing
- Vocalization
- Restlessness
- Seeking boar, solicitation
- Swollen, deep red vulva
- Mounting
- Off feed
- Ears pricked
- Elevated rectal temperature
- Quiver
- Tail twitch, held up
- Evidence of viscous, sticky vaginal mucous
- In general, the stickier the mucous, the stronger the heat (use the “thumb test”)
what is the normal length of the wean to estrus (WEI) interval? what is the target for breeding
4-5 days
Target >90% of sows (P>1) bred by 6d
as WEI _____, NPD _____
increases, increases
fertility is lower when sows are bred at more than ___ days
5
risk factors for long WEI/anestrus (3)
– Young sows
– Inadequate lactation nutrition
– Inadequate heat detection
components of gilt management (8)
- Sufficient space
- Housed in pens
- Daily exposure to mature boars
(15 minutes per day) - Relocate gilt > Estrus 5-7 days later
- Identify first estrus
- Breed at 2nd estrus
- Re-mix anestrus gilts
- Breed every 12 hr* while in heat
(* Shorter duration of estrus than sows)
when can you use PG600 to induce estrus in gilts
= will induce a fertile estrus in gilts that have not had a first estrus
what is another drug you can use to synchronize females
Oral progesterone (Regumate)
artificial insemination in boars; details surrounding catheters
- Reusable or disposable
- Spiral or sponge tip (sized for gilts & sows)
- Cervical or post-cervical (deep or intra-uterine)
- Personal preference
steps in pregnancy detection (3)
- Stimulate with boar At 18 – 25 d post breeding
- Ultrasound at 24 – 28 d post breeding
- Recheck at 36 – 50 d for repeat sows (2nd regular estrus post breeding ) – part of our goal
boar semen is extremely ____ to temperature change
sensitive
semen storage; temperature to store, how long can it be stored on farm, when does it get damaged
- Store between 15 and 20C; Fluctuations < 2oC
- Most semen is purchased from boar stud and may be stored on-farm for 3 – 5 days
- Sperm damage if < 15 or >20C for 40 minutes
what can you use to induce farrowing? what will it cause? why do you want to induce sows to farrow?
Prostaglandin – causes
– agitation
– sweating, panting
- Why induce sows to farrow?
– Management
– Batch farrowing
when to administer prostaglandin for induction of farrowing? what happens if you give it too early?
Administer:
– Maximum 2 d before normal gestation length of the herd
– ~ 113 - 114 d gestation
If too early:
* increase stillbirths,
* weakborn & splayleg pigs
signs of impending parturition (4)
May secrete milk
May have nesting behaviour, restlessness
May have reduced feed intake
May have raised rectal temp
timing of parturition
- ~4.5 hrs (±2.5 hrs)
- Piglets expelled every 25 minutes (±25 min)
- Placenta (2 horns): generally expelled after last piglet
features of the sow uterus, how to help get piglets out if necessary
Very long horns
Piglets in the horns
To assist, sows need to move piglets to body of uterus
Producers typically monitor parturition and handle dystocia
farrowing rate vs adjusted farrowing rate
Farrowing rate: The proportion of the sows that are bred that go to term (farrow)
Adjusted farrowing rate: accounts for sows not farrowing due to non-reproductive reasons
if farrowing rate is too low, what it important to consider?
- If farrowing rate is too low, important to determine when sows are becoming non-pregnant
– Bred sows are not becoming pregnant
OR
– Pregnant sows are becoming non-pregnan
