Swine Gestation Calculator

Calculate your sow's expected farrowing date. Enter the breeding date to see the full pregnancy timeline and key milestones. Remember: 3 months, 3 weeks, 3 days!

Date when sow was bred

Pig gestation period: 110-120 days (average 114 days = 3 months, 3 weeks, 3 days); Expected Farrowing Date = Breeding Date + 114 days; Range: Breeding Date + 110 to + 120 days; Move to farrowing pen 5-7 days before expected date
Example: Breeding on January 1; Earliest farrowing: April 21 (Day 110); Average farrowing: April 25 (Day 114); Latest farrowing: May 1 (Day 120); Move to farrowing pen: around April 18

How long are pigs pregnant?

Pig gestation period averages 114 days, often remembered as "3 months, 3 weeks, 3 days" (3×30 + 3×7 + 3 = 114). Normal range is 110-120 days. First-time sows may carry 1-3 days longer. Litter size affects gestation: larger litters (12+ piglets) tend to be born 1-2 days earlier, smaller litters (under 8) may go 2-3 days longer. Breed influences gestation slightly: commercial breeds (Yorkshire, Landrace): 112-115 days, heritage breeds: 115-120 days. Sows can safely farrow from day 110 onward with good survival rates.

What are the signs that a sow is about to farrow?

Signs of impending farrowing (12-24 hours before): Udder development: "Bags up" 2-7 days before, becomes tight and shiny, Vulva: becomes swollen and relaxed, red and enlarged, Milk: can be milked from teats 12-24 hours before labor (clear → white), Restlessness: pacing, nesting behavior (shredding bedding), Appetite: may skip last meal before farrowing, Temperature drop: rectal temp drops from 102°F to 100°F about 12 hours before labor, Contractions: visible abdominal contractions, Side-lying: sow lies on side, paddling legs. Prepare farrowing crate/pen 5-7 days before expected date.

How many piglets do sows typically have?

Litter size varies by breed and parity: First litter (gilts): 6-10 piglets average, Mature sows (2-5 litters): 10-14 piglets average, Prolific breeds (Meishan, Fengjing): 15-20+ piglets, Commercial lines (selected for litter size): 12-16 piglets. Record litter trends: Litter size increases until 4th-5th parity, then declines. Average piglet survival to weaning: 85-95% with good management. Key factors: proper nutrition during gestation, comfortable farrowing environment, supervision during birth, ensuring all piglets nurse colostrum within first 6 hours.

How do I prepare for piglet farrowing?

Farrowing preparation checklist: 1-2 weeks before: Move sow to clean farrowing pen/crate, disinfect all surfaces, Provide clean, dry bedding (straw preferred for nesting), Install heat lamp or heating pad for piglets (85-90°F zone), Gather supplies: iodine (7%) for navels, clean towels, dental floss (for tying cords if needed), colostrum replacer, milk replacer, iron injections (give at 3 days), thermometer. Day of farrowing: Monitor every 2-4 hours, Record birth times and piglet weights, Ensure each piglet nurses within 6 hours (critical for immunity), Dip navels in iodine, Dry piglets if cold, Count placentas (should match piglet count - retained placenta is emergency). Average farrowing takes 2-5 hours. Call vet if labor exceeds 45 min with no progress.