Your pig has been eating for months, but it is still small. Your neighbor's pig, bought at the same time, is already twice the size. What is going wrong?
"Kung gamay kaayo mokaon ang baboy, naa gyud problema." (If the pig eats very little, there is definitely a problem.)
Slow growth in Philippine backyard pigs almost always comes down to one of five causes. Most are fixable once you identify them.
Expected Growth Rates
Before diagnosing a problem, know what is normal:
| Breed Type | Expected Daily Gain | Monthly Gain |
|---|---|---|
| Native pig | 0.15–0.25 kg/day | 4.5–7.5 kg/month |
| Native × commercial cross | 0.35–0.50 kg/day | 10–15 kg/month |
| Commercial breed (backyard fed) | 0.55–0.75 kg/day | 17–22 kg/month |
If your pig is gaining significantly less than these ranges for its breed type, investigate the causes below.
Cause #1: Internal Parasites
This is the most common cause of slow growth in Philippine backyard pigs.
Research shows that roundworm (Ascaris suum) infection can reduce weight gain by up to 40% and feed conversion by up to 25% (Polley & Mostert, 1980). pig333's health section documents the economic impact of subclinical parasitism on growth performance. Prevalence in Philippine backyard herds ranges from 25–60%.
Signs:
- Pot belly with thin body
- Rough, dull hair coat
- Visible worms in feces (large, white, 15–30 cm)
- Coughing (larval migration through lungs)
- Eating normally but not gaining weight
Fix: Deworm immediately with ivermectin or albendazole. Then deworm every 3–4 months going forward. Deworm the sow 2 weeks before farrowing to reduce piglet transmission.
See How to deworm pigs in the Philippines for detailed protocols.
Cause #2: Poor Feed Quality or Quantity
Pigs need to eat approximately 3–4% of their body weight daily in feed. A 50 kg pig should eat 1.5–2.0 kg of feed per day. If it is eating less — or if the feed lacks protein — growth stalls.
Common feed problems:
- Kitchen scraps only. Scraps are inconsistent and usually low in protein. Pigs on scraps alone grow at half the rate of properly fed pigs.
- Rancid rice bran. Rice bran stored more than 2 weeks in Philippine heat goes rancid. Pigs refuse it or eat less.
- No protein source. Corn and rice bran provide energy but insufficient protein. Without copra meal, fish meal, or soybean meal, pigs grow fat slowly instead of building muscle.
- Not enough feed. Under-feeding to save money actually costs more because it extends the grow-out period.
Fix: Provide a balanced ration with adequate protein (14–16% for growers). See Best feed mix for backyard pigs for a practical formula.
Cause #3: Heat Stress
Philippine daytime temperatures routinely reach 30–37°C. Pigs cannot sweat. Above 25–30°C, pigs enter heat stress and voluntarily reduce feed intake by 80–100 grams per day per degree above their comfort zone.
At 35°C, a finishing pig may eat 500+ grams less per day than at 25°C. Over a month, that is 15 kg less feed consumed — which translates directly to slower growth.
Signs:
- Open-mouth breathing (panting)
- Seeking wet areas constantly
- Reduced eating, especially during the hottest part of the day
- Skin feels hot to touch
Fix:
- Provide shade — direct sun on a pig pen is the worst setup
- Ensure 24-hour water access (pigs drink 30–50% more in heat)
- Sprinkle water on the pig or pen floor during peak heat
- Feed during cooler parts of the day (early morning, late afternoon)
- Improve ventilation — open-sided pens catch more airflow
Cause #4: Chronic Disease
Subclinical infections — diseases that do not make the pig visibly sick but reduce appetite and nutrient absorption — are common in backyard herds. ThePigSite's diagnostic guides cover how to identify these hidden growth robbers.
Common culprits:
- Chronic respiratory infections (mild cough, slight nasal discharge)
- Mange (constant itching = stress = less eating)
- Subclinical scours (soft stool, not full diarrhea)
- Stomach ulcers (from finely ground feed or stress)
Fix: Have a veterinarian examine any pig that is growing significantly below expected rates despite good feeding. Municipal vet consultations are usually free for registered farmers. Nutritional deficiencies can also cause slow growth — see pig vitamins and supplements to check if your ration is missing key micronutrients.
Cause #5: Overcrowding and Stress
Pigs that are overcrowded fight more, eat less, and get sick more often. Stress hormones directly suppress growth.
The recommended floor space is 0.8–1.0 sq.m per finishing pig. Five pigs in a 2m × 2m pen (0.8 sq.m each) is the absolute minimum — 1.0 sq.m or more is better.
Fix: If your pigs are visibly competing for feed, fighting, or have bite wounds on ears and tails, they need more space or smaller groups.
A Quick Diagnostic Checklist
When your pig is not gaining weight, work through this in order:
- When was the last deworming? If more than 3 months ago → deworm now.
- Is the pig eating its full ration? If not → check feed quality and heat stress.
- Does the feed have adequate protein? If just corn/scraps → add protein source.
- Is there shade and water 24 hours? If not → fix immediately.
- Is the pig coughing, scratching, or has diarrhea? If yes → call veterinarian.
- How many pigs per pen? If overcrowded → separate or expand.
Bisaya / Cebuano
Para sa mga mag-uuma
Ngano dili motubo ang baboy? Lima ka rason:
- Ulod — ang pinaka-kasagaran. Nag-menos og 40% sa tubo. Pa-deworm kada 3–4 ka bulan.
- Sayop nga pagkaon — kinahanglan og protina (copra meal, fish meal), dili lang darak ug mais.
- Init kaayo — kung sobra sa 30°C, mokunhod og kaon ang baboy. Butangi og landong ug tubig.
- Sakit — bisan dili makita, ang gamay nga sakit makapakurog sa tubo. Padala sa vet.
- Puno kaayo ang tangkal — kung mag-away ang baboy, dili kaayo mokaon.
"Ang baboy nga hilom, mao'y labing tambok." (The quiet pig is the fattest — a pig that eats and rests calmly gains weight fastest.)
Learn More
- Why did my pig stop eating? — diagnosing sudden feed refusal
- Complete feed formulation guide — get the protein balance right
- Pig feed consumption chart — how much should your pig eat
- FCR Calculator — measure your feed conversion ratio
- Feed Cost Calculator — optimize your feed spending
Sources: Polley & Mostert 1980 (parasite effects on weight gain), Lee et al. 2005 (Philippine smallholder pig management constraints), MSD Veterinary Manual (nutritional diseases of pigs), FAO Farmer's Handbook on Pig Production, pig333.com heat stress research.
