Flashcards in Hannah's Cards Deck (50)
What parity sows are the best reproductive performers?
What is the ideal parity distribution?
What should the proportion (%) of parity 3-6 sows be in the herd?
Most at parity 1, then decreasing to >7.
50% parity 3-6.
At what parity do sows become profitable?
What are the six golden rules for managing gilts?
1. Daily boar contact from 175-196 days of age (25-28 weeks of age) to bring on first heat quicker
2. SKIP FIRST HEAT
3. Age at first mating = 210 – 238 days of age (30 -34 weeks) MATE ON SECOND HEAT
4. Weight at first mating 150kg (130-160kg)
5. Crate train them
6. Mate and leave them (low stress)
Why are gilts the lowest reproductive performers?
• Less piglets + lower birthweight (still growing when mated for the first time- 30wks)
• Lower colostrum and milk production (mammary glands not fully developed)
> Higher piglet mortality, disease + lighter weaning weights
• Longer weaning to service interval
Most herds = 80% sows, 20% gilts
Target piglets born alive per litter?
(10 minimum, 11 desirable)
Depends on sow weaning age
Target farrowing rate? (%)
86% for gilts
When do you "ad lib" feed sows?
Lactation and post weaning/mating.
(Never ad lib feed boars.)
Target BCS for a sow?
Target pre-weaning mortality? (%)
Target pigs weaned/mated female/year?
Target female mortality? (%)
Target weaning to first service interval?
Target number of litters/mated female/year?
Target post-weaning mortality? (%)
How many eggs does each female produce?
After ovulation, how long until the eggs die?
Die 8 hours after ov.
When should fertilisation occur after ovulation for optimal fertility?
6 hours after ov is optimum.
How long does sperm survive for? (in the female)
How many (%) pigs ovulate while display oestrus?
List signs of oestrus.
- Calling sow ("honking")
- Restless, nervous, inappetent
- Red swollen vulva
- Ears erect in presence of boar
- + back pressure test in presence of boar
- Tacky vaginal discharge
When to inseminate?
(she will need a boar to show oestrus)
24 hours after displaying "male" behaviour & honking she stands to back pressure.
Boar test positive & back pressure positive.
Inseminate 12-36 hours after standing onset.
(middle 24 hours, stands for 48 hours)
Semen survives for 24 hours.
Come into heat day 3-7 after weaning.
To save energy, she will only stand to back pressure for 15 mins of every hour. For the remaining 45 mins she will act normal.
Describe natural mating process.
Mating pen: no obstructions, >2.5m wide
Observer: Non-spermicidal vinyl gloves, assist boar if required, be gentle and quiet.
Ejaculation (anal winking of boar) for >3 mins
Describe the AI process.
Gloves (not latex/powdered)
Lube 2cm below catheter tip
Give sow nose-nose contact with boar (for uterine contractions)
Put catheter in cervix (point upwards to avoid urethra, 30 degrees)
Attach semen bag
Stimulate sow + push in semen
(If drawing semen in too quickly, slow down flow by lowering tube)
Leave catheter in 5-10 mins, remove
Leave for another 5-10 mins before moving
(don't touch catheter tip or opening of semen bag)
How to stimulate a sow? (manually)
Weight on sow.
Rub back & udder.
Pull loose skin on flank.
18-24d: boar test (regular return)
25-35d: boar test (irregular return)
28d: doppler machine for uterine pulse
8wks: by eye
Male and female surgeries? Indications?
Hysteriectomy (specific pathogen-free piglets)
Embryo transfer (transfer sterile genetics)
Vasectomy (V boars, male characteristics + no preg)
Castration (desexing 7-10d, no anaesthesia <21d)
Surgery drugs & protocol?
Ketamine & xylazine IV (jugular)
Zoletil (not in food producers) & xylazine IM (behind ear)
(15-20 mins duration)
Acepromazine PO (pigs with attitude)
Pain relief + ABs after.
Why don't we use halothane in pigs?
Malignant hyperthermia (stress gene response)
How long to fast before surgery?
Fast 6-8hrs before, keep water.
2 methods of intubation.
Endotracheal & nasal intubation.
Inducing oestrus drugs?
**Inducing farrowing drugs + doses + route?**
PGs (no corticosteroids in pigs)
Lutalyse 2mL IM
Juramate 0.7ml IM
Estrumate 0.7ml IM
Can half dose and give in vulval skin fold before 6 hours apart
DON'T induce before 113d! (premature> death)
Don't self inject! (human abortion)
Synchronising oestrus drugs?
To be joined into herd, cycling already, synchronise in mating week
When to assist farrowing & drugs?
Indication: farrowing started, no piglet for 30 mins
Max 2 doses (more= piglet has a problem)
ONLY when cervix fully dilated (check before)
3 things needed to align at ovulation?
Boar test +
Back pressure +
Sperm lifespan (24hrs)
How often to heat check?
Heat check twice daily .
Visible oestrus: 15 mins of every hour.
3 methods to inseminate.
Where does the sperm go?
Natural mating: cervix
250-400ml, 60-80 bill, 5-10 mins (most)
Traditional AI: cervix
70-80ml, 2-3 bill, 3-5 mins
Post cervical AI: uterine horn
15-40ml, 0.5-1.5 bill, 10-15 secs (least)
How long is a female's cycle?
Explain the stages of pregnancy (day 0-35)
Day 0: ovulation + fertilisation
Day 2: embryo enters uterus from oviduct
Day 7: embryo hatches
Day 10: free embryo releases oestrogen sulphate
Need min 5 embryos in uterus (SIGNAL ONE!)
Day 14-17: embryo implants, releases oestrogen sulphate (SIGNAL TWO!)
Day 35: bone formed in foetus
What happens if there is no 1st signal?
No day 10 signal: returns 18-24 d (regular RTS)
What happens if there is no 2nd signal?
No day 14-17 signal: returns 25-35 d (irregular RTS)
What happens if foetus dies ~20d?
Irregular RTS 50d+ (peak 63d)
What happens if foetus dies >35d?
Mummification & pregnancy continues as long as one foetus is alive
How do you age a foetus?
e.g. crown rump length=30mm
Crown rump length/3 + 21 = days old
e.g. 30/3 + 21 = 31d
Irregular: Regular RTS ratio?
Regular= 3wk, 6wk ...
Irregular= any other
Target RTS? (%)
Target abortion? (%)
3 types of catheters.
Catheters: clear tip, foam tip, spirette
Sperm storage (temp, time, maintenance...)
Store sperm at 16-18C (fertility reduces greatly after 2d)
In extender (85mL, >2-3bill)
Turn twice daily so it doesn't clump.