A herd book works when any litter can be traced back to a sow and forward to its outcome without detective work. On a smallholding the temptation is a single running list — services, farrowings, and weanings jumbled in the order they happened — and within a year that list can no longer answer the only questions that matter: which sow reliably raises big litters, which boar pairing worked, and which sow struggled twice in a row. One page per sow, with events recorded in the same order every time, answers all three at a glance.
The Fields on a Sow's Page
Head the page with the sow herself: her identity, her year of birth, and where she came from. The first entry for each litter is the service: the service entry itself and the boar used, written at the time rather than reconstructed later. From that entry, work out the expected farrowing and write it beside the service: a pig's gestation runs to about 114 days, counted by keepers as three months, three weeks, and three days, so the expected window can be penciled in the day she is served, allowing a few days either way in practice. Add a short note of her condition at service. That single page header plus the service entry is what turns farrowing from a surprise into a planned week, with the pen ready and checks arranged around the expected window.
Farrowing and Weaning Entries
The farrowing entry records the outcome in fixed parts: how many were born alive, how many were stillborn, and how the farrowing went in plain terms. Fostering is recorded the same day and on both pages it touches: piglets moved to another sow are noted as fostered out on their birth sow's page and fostered in on the receiving sow's page, with the numbers adjusted on each, because a litter count that ignores fostering credits and blames the wrong sows. Note any piglet losses after farrowing as they happen, with the litter age in the entry label — the first week entry reads very differently from a loss near weaning. The weaning entry closes the litter: the weaning entry itself, commonly around eight weeks on smallholdings, the number weaned, and a line on the sow's condition as she leaves the pen, which is the starting point for decisions about her next service.
Start a page the day a young sow is bought or first served, not at her first farrowing, because the service entry for the first litter is the one that tends to go missing. Keep a short index page at the front of the book listing each sow and where her litters stand — served, farrowed, weaned — so a morning at the pens starts from the index rather than from flipping pages. When a sow leaves the herd, close her page with a final line saying so and why in plain terms; closed pages are what make the remaining pages trustworthy when you compare sows across years.
Reading a Sow Across Litters
With litters stacked on one page, patterns show themselves. A sow whose second litter entry matches her first — strong numbers born alive, few losses, a good weaning count — is the backbone of a small herd. A sow whose entries show shrinking litters, repeated fostering out because she could not rear her own, or poor condition at successive weanings is telling you something a single litter never could. Read before serving, the book also settles boar questions: which pairing produced the litter that thrived is there in the service entries. The book lives in the herd's Pet Passport records, keeping every sow's page together and portable. Kept current at the pen, the Pet Passport herd file on KinsLe replaces memory with a sequence a keeper can trust when planning the next mating.