🐖 Swine Gestation Calculator

Plan farrowing schedules, housing, and nutrition by calculating sow gestation timelines.

Record the AI or natural service date. Rebreedings should be logged separately.

Gestation Overview

Swine follow the “3 months, 3 weeks, 3 days” rule: about 114 days. Monitor for farrowing signs as early as day 112.

How to Use This Calculator

1

Track breeding events

Enter the insemination date for each sow to build a farrowing schedule.

2

Monitor gestation progress

Use the due window to time vaccinations, feed adjustments, and crate moves.

3

Prepare for farrowing

Gather clean towels, heat sources, and ensure farrowing stalls are sanitized before the early window.

Formula

Farrowing Date ≈ Breeding Date + 114 days

Known as the “3-3-3 rule,” sow gestation approximates 3 months, 3 weeks, and 3 days. The ±2 day window covers natural variation.

Full Description

Predictable farrowing schedules help swine producers optimize labor, reduce stillbirths, and manage sow condition. This calculator offers quick due date projections alongside reminders for diet and housing changes.

Maintain accurate breeding and farrowing records to evaluate conception rates, weaning performance, and sow productivity throughout multiple parities.

Frequently Asked Questions

How do I confirm pregnancy in sows?

Ultrasound around day 28–30 or Doppler heartbeat detection offers reliable confirmation.

When should I move sows to farrowing crates?

Typically 3–5 days before the due window (around day 110) to allow acclimation and pen sanitation.

What are signs that farrowing is near?

Reduced appetite, nest-building behavior, and milk let-down occur 12–24 hours prior to labor.

What if farrowing exceeds the late window?

Monitor closely and consult a veterinarian if no farrowing activity occurs by day 118 or if the sow shows distress.