Definition: A weight log is a dated series of scale (or carefully estimated) live weights. Clean logs produce honest ADG and fair projections; noisy logs produce panic decisions.
Best practices:
- Weigh on a consistent schedule (weekly is ideal for market hogs).
- Same scale, similar time of day, similar gut fill when possible.
- Log the number the same day — memory is not a data system.
- Note health events, ration changes, or heat waves that explain outliers.
Worked example: Start 80 lb May 1; June 6 = 150 lb (36 days) → ADG ≈ 1.94 lb/day. Skip two weeks without logging and you lose the early signal that gain is stalling.
No scale? Use a tape estimate carefully, then verify. Try the tape weight estimator and the ADG calculator. Related guides: what is ADG and project fair weight.
Next step: Save weigh-ins in ShowPen so history compounds into a record book.