One of the most frustrating experiences in backyard pig breeding is not knowing whether your sow actually conceived. You had the boar service her, you waited, and now you are not sure if she is pregnant or if you need to try again.
"Nagburos na ang anay." (The sow is already pregnant.)
There is no simple blood test available to backyard farmers. But there are reliable signs you can observe — and the most important one comes just 21 days after mating.
The 21-Day Test: No Return to Heat
This is the most reliable early indicator available to backyard farmers without ultrasound equipment.
A sow's heat cycle is approximately 21 days. If she was successfully bred, she will not show heat signs at the 21-day mark. If she shows heat again — restlessness, swollen vulva, mounting behavior, standing still when you press on her back ("standing reflex") — she did not conceive.
Mark the breeding date on your calendar immediately. Then watch carefully at days 18–24.
"Gipanglaway na ang anay." (The sow is drooling/in heat.) — This is what you do not want to see at the 21-day check.
Progressive Signs Through Pregnancy
Weeks 1–3: No visible signs
Nothing externally visible. The only test is the 21-day heat check.
Weeks 4–8: Behavioral changes
- Calmer temperament — less restless, less interest in the boar
- Increased appetite — eating more than usual
- Weight gain begins — steady increase, concentrated in the body (not legs)
Weeks 8–12: Physical changes become visible
- Belly begins to enlarge and drop — noticeable from around day 60–70
- Teats become more prominent — slight enlargement
- Steady weight gain — a pregnant sow gains 30–50 kg over the full gestation
Weeks 13–16 (last month): Obvious signs
- Large, low-hanging belly — unmistakable at this point
- Udder development — teats swell, especially in the last 2 weeks
- Milk letdown test — from about 24–48 hours before farrowing, you can gently squeeze a teat and express milk or waxy colostrum. This confirms farrowing is imminent.
- Nesting behavior — sow becomes restless, paws at bedding, gathers straw or materials
- Vulva swells — may show mucus discharge in the final 24 hours
- Restlessness — lying down, standing up, lying down again in the 12–24 hours before delivery
The 114-Day Rule
Pig gestation is remarkably consistent: 114 days — easy to remember as 3 months, 3 weeks, and 3 days.
Normal range is 112–117 days. First-time gilts sometimes farrow 1–2 days earlier.
If you know the breeding date, calculating the due date is simple. This is why writing down the breeding date is the single most important record in pig breeding.
Preparing for Farrowing
Start preparing 7 days before the due date:
- Move the sow to a clean farrowing pen. At least 2m × 2.5m. Scrub the floor with lime (apog) before she enters.
- Install guard rails — a horizontal bar 20–25 cm from the wall and 25 cm above the floor. This prevents crushing, the #1 killer of newborn piglets.
- Provide bedding — rice straw or dried banana leaves. Never bare concrete for farrowing.
- Reduce feed slightly in the last 2–3 days before expected farrowing. A full gut makes delivery harder.
- Ensure abundant clean water — a farrowing sow needs more water than at any other time.
Supplies to have ready:
- Clean rags or towels (for drying piglets)
- Iodine / Betadine (for navel dipping)
- Thread or dental floss (for tying umbilical cord)
- Clean scissors (sterilized, for cutting cord)
- Iron dextran injectable (inject piglets on day 3 to prevent anemia)
Common Problems
Sow has no milk after farrowing (agalactia)
If the sow does not let down milk within a few hours of farrowing, piglets will starve. Causes include mastitis, metritis, or severe stress. This is a veterinary emergency — call your municipal vet immediately.
Too many piglets for available teats
Average litter is 8–12 piglets, but sows have 12–14 functional teats. In large litters, the weakest piglets get pushed off. Cross-foster to another sow that farrowed around the same time, or bottle-feed with commercial milk replacer or fresh goat's milk.
Inbreeding
Very common in barangays where one boar services all sows for years. Inbred litters are smaller, piglets are weaker, and stillbirths increase. Replace or exchange boars every 1–2 years.
Bisaya / Cebuano
Para sa mga mag-uuma
Unsaon pagkahibalo kung nagburos na ang anay (sow)?
- 21 ka adlaw human sa pagpahabal — kung wala na mobalik ang heat (init), nagburos na siya
- 2 ka bulan — magsugod og dako ang tiyan, mokalma ang kinaiya
- 3 ka bulan — klaro na gyud nga dagko ang tiyan, modako ang mga suso
- 114 ka adlaw — manganak na. (3 ka bulan, 3 ka semana, 3 ka adlaw)
Importante gyud: isulat dayon ang petsa sa pagpahabal! Kung dili nimo mahinumduman, dili nimo makalkula kung kanus-a manganak.
Bago manganak: limpyohi ang tangkal, butangi og guard rail, andama og trapo, Betadine, ug iron injection.
Learn More
- How many piglets does a native pig usually have? — litter size by breed
- Why piglets die in the first week — how to prevent neonatal mortality
- How to build a backyard piggery — farrowing pen design
- Best pig breeds for small farmers — breeding traits by breed
Sources: FAO Farmer's Handbook on Pig Production (breeding and reproduction chapter), ThePigSite breeding management guides, DA-ATI swine production training modules, UPLB College of Veterinary Medicine swine reproduction manual.
