Yes, a male pig (boar) can and will kill piglets, including his own offspring. This is one of the main reasons boars are kept separated from sows and their litters in both farming and pet pig settings. The behavior isn’t rare or accidental. It’s a well-recognized risk that pig owners and farmers routinely manage by keeping males away from newborns entirely.
Why Boars Kill Piglets
Boars don’t have a strong paternal instinct. Unlike some species where the father helps protect or raise young, male pigs show little interest in caring for piglets and may actively harm them. A boar can bite, toss, or step on newborns, and a single bite from an adult male is enough to kill a piglet that weighs only a few pounds at birth.
Several factors drive this behavior. Boars may see piglets as competition for food, especially if they’re housed together and sharing the same feeding area. A nursing sow also isn’t available for mating, so killing her litter can bring her back into heat sooner, giving the boar another chance to breed. This type of infanticide is seen across many species where males benefit reproductively from eliminating existing young. Boars can also simply be rough and aggressive animals. Even without intent to kill, their size and behavior around small piglets creates a lethal situation.
Sows Can Be Dangerous Too
Boars aren’t the only threat to newborn piglets. Mothers themselves sometimes attack their own litters, a behavior called “savaging” in pig farming. In one study of farmed wild boar, about a third of sows showed some level of aggression toward their newborns, and two out of 24 sows killed one or more of their piglets. The risk varied significantly by genetic line, with some lines showing aggression rates above 60% while others stayed below 15%.
Savaging is more common in first-time mothers and in sows that are stressed, confined in unfamiliar environments, or startled during birth. It can range from snapping at piglets to actively biting and killing them. Experienced sows with calm temperaments rarely show this behavior.
Crushing Is the Biggest Killer
While infanticide gets the most alarming search results, the reality is that accidental crushing by the mother is the leading cause of piglet death in the first week of life. In a study tracking over 9,500 live-born piglets, about 11% died within the first week. Of those deaths, nearly 64% were from crushing, where the sow rolled onto or stepped on a piglet. The remaining 36% died from other causes including disease, starvation, and chilling.
This is relevant because it puts the infanticide risk in context. Keeping a boar away from piglets is straightforward and eliminates that danger completely. The harder problem for pig owners is managing the everyday risk of a 300- to 600-pound sow accidentally lying on a piglet that weighs two or three pounds.
How to Protect Piglets
The single most important step is physical separation. The boar should have no access to the sow and her litter from the time she’s close to farrowing (giving birth) through at least the first several weeks. Many farmers separate the boar well before the due date, since sows can become aggressive toward males as they prepare to give birth.
For the sow’s own litter, providing a warm, enclosed creep area that only piglets can access gives them a safe retreat. Piglets naturally seek warmth, so a heat lamp or heated pad in the creep area draws them away from the sow’s body when they’re not nursing, reducing the chance of being crushed. Supervision during and immediately after birth is also valuable, since the first 48 hours carry the highest risk for both savaging and accidental crushing.
If you’re raising pet pigs or a small herd, keep the boar in a separate pen or pasture with secure fencing. Pigs are strong and motivated escape artists, so a single strand of electric fence may not be enough. Solid panels or well-maintained hog wire with electric backup works best. Reintroduction can happen gradually once the piglets are older, larger, and fast enough to get away from an aggressive adult, typically around four to six weeks at the earliest, though many owners wait longer or keep boars permanently separated from young stock.