A litter log earns its keep at the next mating decision, when you are trying to remember whether a sow is genuinely productive or just memorable. Memory flatters; a card that was filled in honestly at each farrowing does not. The format below is deliberately plain — a page per litter, kept with the sow's own record — because a system simple enough to complete by lamplight in the farrowing pen is the one that actually gets completed.
One Record Per Litter, on the Sow's Own Card
Start a fresh section for every farrowing rather than a running farm diary. Head it with the sow's name or number, her parity — which litter of her life this is — the boar she was served by and the day she farrowed. Record the count as it was found and finished: total born, born alive, and born dead, keeping those categories separate rather than merging them into a single flattering figure. Add the practical notes that will matter in a fortnight: how she milked, whether she was unsettled or turned on any piglets, and any piglet that started small or struggled, so the losses column later has context rather than mysteries.
The Numbers That Must Add Up
The whole value of the format is an equation a child could check. Born alive, plus any piglets fostered onto her, minus any fostered off to another sow, minus deaths, must equal the number she weans. If the weaning count does not reconcile, something was missed on a busy day — a death unrecorded, a foster swap forgotten — and it is far easier to catch standing in the pen than at the end of the season. Fostering lines deserve the same care as births: write which sow each piglet went to or came from, on both cards, so neither litter's figures are quietly distorted.
Writing Losses Down Honestly and Promptly
Losses are where litter records usually start lying. A piglet found dead gets skipped until the count at weaning, stillborns get folded into born alive to make the sow look better, and by the end nobody knows her real figures. Record every death on the day, with a brief factual note of the likely cause as you found it — laid on, chilled, scouring, fading despite feeding. These notes are not blame; they are the only way patterns show themselves. Three litters losing piglets the same way in the first two days is a housing or management clue, and it is invisible if the deaths were never written down.
What the Finished Log Tells You About Each Sow
With a card per litter, a sow's career reads at a glance: litter size by parity, her losses pattern, how many she actually rears to weaning rather than how many she produces, and whether fostering usually flows toward her or away from her. That is the evidence base for the real decisions — which sows to breed again, which gilt to keep as a replacement, which bloodline is quietly carrying the herd. Update the card while the farrowing pen is still fresh in your mind, and the record stays an asset instead of archaeology.
Keeping those cards together is the habit KinsLe's Pet Passport supports — a sow's records held in one packet across her breeding life, so her next mating is decided from her whole history, not from memory.