A first-time gilt who has just bitten her own piglet is not a lost cause yet. Of 6,625 gilts on seven farms, 2.9% killed piglets (Harris & Gonyou 2003), and savaging is less common at later litters (Chen et al. 2008). The first 30 minutes decide. Get the piglets out, calm the gilt, then decide.
The First 30 Minutes
If you walked in mid-savage, do this in order:
- Get the piglets out. Into a warm box (35°C) lined with a clean towel. Rub them dry. The gilt sees no piglets, hears no squealing, and the trigger is removed.
- Make sure the farrowing finished. A retained piglet or placenta keeps her in pain and aroused. If you can feel a piglet in the canal, she needs help — see difficult farrowing.
- Quiet the room. Strangers, dogs, lights, noise — all out. Sit out of her direct line of sight if you must stay.
- Decide on sedation. If you have Stresnil, give it now. If not, give her 30-60 minutes of silence and try a calm reintroduction. Most rural agrivets don't stock it.
- Reintroduce one piglet at a time once she is recumbent. If the first latches, add the rest. If she lunges, pull the piglet and try again in an hour.
After Stresnil, keep piglets away at least 20 minutes, until she lies on her side (ThePigSite). Never foster extra piglets onto a gilt in her first 12 to 24 hours; NADIS says it can trigger attacks (NADIS).
For a gilt you're worried about, NADIS lists boxing piglets away during farrowing as standard prevention. I box each piglet once it's breathing, then return two or three after she finishes and lies flat, grunting. It means one long night with a flashlight. Worth it.
Tell Savaging From The Two Things People Confuse It With
| Sign | What it is | What to do |
|---|---|---|
| Piglet has bite wounds on head, neck, or legs; sow barked or lunged | Savaging (active aggression) | Separate, sedate, possibly cull |
| Piglet is dead with crushed thorax, no bite wounds, sow lay down on it | Overlay (accidental crushing) | Pen design fix: anti-crush rails, creep area |
| Sow is eating an already-dead piglet, no aggression toward live ones | Post-mortem cannibalism (cleanup behaviour) | Look for the upstream cause: stillbirth, MMA, dystocia |
These three get lumped together as "kinakain ang biik," but the fix for each is different. A savager bites; a crushing sow lies down; a cannibal scavenges what is already dead.
Why Gilts Do It
The triggers stack:
- First-time anxiety. Gilts savage roughly 3x more than older sows.
- Painful farrowing. Dystocia, retained placenta, large piglet. Pain plus newborn squeals = aggression.
- Crowding and crating stress. Especially if the gilt was crated less than 3 days before farrow.
- Audience. A stranger watching, or even a familiar person standing in her sight line, makes it worse.
- Genetics. Breeding plays a part. ThePigSite's disease guide finds it more common in purebred Large White gilts than in Landrace or Duroc (ThePigSite, Savaging of Piglets). If your boar's daughters keep doing this, the boar is the problem.
- Body condition. Overconditioned gilts (BCS above 3.5) have harder farrowings and savage more.
- No nesting material. Rice straw or chopped kogon to redirect onto reduces incidence.
What the studies found
Of 6,625 crossbred gilts on seven farms, 5.3% showed aggression toward piglets and 2.9% killed piglets; continuous light reduced fatal savaging and recorded piglet squeals did not help (Harris & Gonyou 2003). Leave a dim bulb on.
In Chen et al. (2008), nest building didn't predict savaging but restlessness did: savagers changed posture more often before and during farrowing (Chen et al. 2008). A gilt that keeps getting up and flopping down in early labour needs the box ready.
The Week Before Farrowing
Get her due date from the farrowing calculator, then:
- Move her in at least 3 days early. NADIS says gilts crated just before farrowing are often agitated, and that gilts with little human contact settle worse. Scratch her back at feeding, same person daily (NADIS).
- Don't let her get fat. NADIS links excess condition to savaging and suggests swapping some feed for bran pre-farrowing. Darak works.
Heat matters too. Muns et al. (2016) found raising the farrowing room from 20°C to 25°C made crated sows breathe faster, run hotter and eat less (Muns et al. 2016, via 3tres3). Savaging wasn't measured, but PH afternoon pens run well past 25°C, and a panting gilt isn't calm. Shade the roof, fan her head end, keep the heat in the piglet box.
Sedation: How Much Stresnil
Azaperone (Stresnil, 40 mg/mL) is the standard tranquiliser for an aggressive sow.
The figures below are from the Stresnil 40 mg/mL product summary on the HPRA register, which lists "treatment of aggression in sows i.e. in sows that do not accept their new-born piglets, or bite them" as an indication.
- Dose: 2 mg/kg IM, which is 1 mL per 20 kg
- Volume: for a 150 kg gilt, about 7.5 mL (do the math for your animal)
- Effect: she should accept her piglets ½ to 1 hour after the shot
- Duration: 1 to 3 hours, depending on dose and weight
- Meat withdrawal: 18 days
The same label warns that too low a dose may not curb aggression and too high a dose can bring it back on waking, so weigh or tape-measure her rather than guess. See how to inject pigs for IM technique.
PH availability is the real problem. Stresnil is not commonly stocked at provincial agrivets, and it is a prescription drug, so the realistic route is a private or municipal vet who can bring or order it. Ask your vet before farrowing night, not during it.
If no Stresnil, no vet, and the gilt keeps attacking after 60 minutes of quiet recovery, switch plans and hand-rear the litter.
Hand-Rearing The Litter
Most PH backyard farmers can't foster. Hand-rearing is the realistic answer.
The 24-hour colostrum window is non-negotiable. Piglets need around 150 mL/kg birth weight in the first 16 hours to absorb antibodies. After 24 hours the gut closes and missed colostrum cannot be recovered.
In order of preference:
- Milked from the gilt herself, even between attacks, if you can restrain her safely. A vet can sedate her for milking.
- Bovine colostrum from a freshly-calved cow, if any neighbour has one. Imperfect but real antibodies.
- Commercial piglet milk replacer (OptiLac and similar). Rare outside Manila and Cebu vet supply houses.
- Backyard mix: evaporated or condensed milk diluted with warm water plus a raw egg yolk per cup. Not as good as anything above, but better than nothing past hour 24.
See why piglets die in the first week for the full neonatal protocol and iron injection schedule.
Cull Or Second Chance?
The cleanest empirical rule:
- First-time savaging, 1-2 piglets killed, gilt responded to sedation and let the rest nurse: give her a second chance. Savaging is less common at later litters (Chen data below).
- Savaged a second litter, killed 3+ piglets despite intervention, or seriously injured survivors: cull.
- Same line keeps producing savagers: suspect the boar, not just the gilts.
Chen's data also show why a second chance is reasonable: 10.7% and 14.6% of gilts savaged on two farms, versus 5.3% and 6.25% of sows at their second farrowing (Chen et al. 2008). Next time, move her early and have the box ready.
A sow that fails her second farrow is unlikely to ever be a good mother. The economics and the welfare both point the same way.
Late-gestation pain triggers savaging, prolapse, and lameness; see the pig limping guide and prolapse first aid.
Bisaya / Cebuano
Para sa mga mag-uuma
Kung ang anay nimo (labi na ang first-litter nga gilt) mokaon o motuklaw sa iyang biik, ayaw og kahibulong, dili pa kana sentensya sa kamatayon. Kuhaa una ang biik, ibutang sa init nga kahon (35°C), pahilumon ang palibot. Daghan nga pagsavage gikan sa kasakit sa pagpanganak: tan-awa kung naa pay biik nga wala makagawas, o kung wala mahuman ang placenta.
Kung naa kay Stresnil, dosis 2 mg matag kilo nga IM (1 mL matag 20 kilo), mga 7.5 mL para sa 150 ka kilo nga anay. Lisod kini pangitaa sa probinsya nga agrivet. Ang oxytocin dili gamiton para mopugong sa pag-attack, kana para sa retained piglet ug pagpa-gatas lang. Sa unang sayop, hatagi siya og second chance. Kung mausab sa sunod nga panganak, ihawon na lang. Sa datos ni Chen, mas talagsaon ang pag-savage sa ikaduhang panganak kaysa sa una.
Sources
- MSD/Merck Vet Manual: Behavior of Swine
- NADIS: Savaging of Piglets (cull rule, crating 3+ days ahead, boxing piglets)
- Harris & Gonyou 2003, Can. J. Anim. Sci. 83:435-444
- Chen et al. 2008, Appl. Anim. Behav. Sci. 109:238-248
- Muns et al. 2016, J. Anim. Sci. 94:377-384 (3tres3 summary)
- ThePigSite: Savaging of Piglets / Cannibalism (first-litter gilts, Large White over Landrace and Duroc, straw before farrowing)
- AHDB: Colostrum Management for Pigs (150 mL/kg, 24-hour window)
- HPRA: Stresnil 40 mg/ml Solution for Injection for Pigs, product summary (2 mg/kg sow aggression dose, 1-3 h duration, 18-day meat withdrawal)
