Pig (Sow/Boar) — Feed Requirements Guide
Sows and boars are the breeding stock of swine operations, requiring carefully managed nutrition to optimize reproductive performance and longevity. A mature sow at 400 lbs has widely varying feed requirements depending on production phase, ranging from 4-6 lbs per day during gestation to 12-18 lbs per day during lactation. Swine are monogastric animals that require amino-acid-balanced diets with high energy density, unlike ruminants that can derive nutrition from fibrous forages. Lysine is the first-limiting amino acid in swine diets and is the basis for formulating protein levels. Sow nutrition directly affects litter size, piglet birth weight, milk production, and the sow's ability to rebreed promptly after weaning. Modern swine genetics have increased litter sizes to 12-16 piglets, placing enormous nutritional demands on lactating sows.
Pig (Sow/Boar) Nutritional Requirements by Life Stage
The table below shows how dry matter intake, protein requirements, and feed costs change across the 3 life stages of pig (sow/boar) production. Life stage adjustments account for the dramatically different energy and protein demands of lactation, growth, gestation, and maintenance. Click any life stage for a dedicated page with detailed feeding recommendations and management tips.
| Life Stage | DMI Adj. | Daily DMI | Protein % | Daily Protein | Monthly Cost* |
|---|---|---|---|---|---|
| Gestating Sow | 0.7x | 8.4 lbs | 14% | 1.2 lbs | $21.48 |
| Lactating Sow | 1.5x | 18.0 lbs | 18.2% | 3.3 lbs | $46.02 |
| Gilt Development | 1.1x | 13.2 lbs | 16.1% | 2.1 lbs | $33.75 |
*Monthly cost estimated using grass hay at $150/ton. Actual costs vary by feed type and region.
Recommended Feeds for Pig (Sow/Boar)
The following feeds meet both the minimum crude protein and TDN requirements for pig (sow/boar) at maintenance level (14% protein, 75% TDN) when fed as the sole feed source. In practice, most feeding programs combine multiple feed ingredients to optimize cost and nutritional balance.
| Feed | Protein | TDN | As-Fed/Day | Cost/Ton |
|---|---|---|---|---|
| Soybean Meal | 44% | 84% | 13.3 lbs | $450 |
| Cottonseed Meal | 41% | 75% | 13.2 lbs | $380 |
| Distillers Grains (Dried) | 27% | 86% | 13.3 lbs | $200 |
| Corn Gluten Feed | 21% | 80% | 13.6 lbs | $200 |
| Broiler Starter | 22% | 78% | 13.3 lbs | $450 |
Feeds Requiring Supplementation
These feeds meet either the protein or TDN requirement but not both, and would need to be combined with other feeds in a balanced ration. The table indicates which nutritional requirement is met and which needs supplementation.
| Feed | Protein | TDN | Protein OK? | TDN OK? |
|---|---|---|---|---|
| Alfalfa Hay | 18% | 58% | Yes | No |
| Haylage (Baleage) | 14% | 60% | Yes | No |
| Whole Corn | 9% | 88% | No | Yes |
| Cracked Corn | 9% | 88% | No | Yes |
| Barley | 13% | 84% | No | Yes |
| Wheat Bran | 16% | 67% | Yes | No |
| Canola Meal | 36% | 74% | Yes | No |
| Layer Pellets | 16% | 70% | Yes | No |
| Fat Supplement (Bypass Fat) | 0% | 180% | No | Yes |
| Urea (Feed Grade) | 281% | 0% | Yes | No |
Feeding Pig (Sow/Boar) at Different Body Weights
Body weight directly determines dry matter intake. The table below shows how daily feed requirements change across a range of body weights for pig (sow/boar) at maintenance level. Use the calculator for custom weights, life stages, and herd sizes.
| Body Weight | Daily DMI | Daily Protein | Monthly Feed | Annual Feed |
|---|---|---|---|---|
| 240 lbs | 7.2 lbs | 1.0 lbs | 216 lbs | 1.31 tons |
| 320 lbs | 9.6 lbs | 1.3 lbs | 288 lbs | 1.75 tons |
| 400 lbs | 12.0 lbs | 1.7 lbs | 360 lbs | 2.19 tons |
| 480 lbs | 14.4 lbs | 2.0 lbs | 432 lbs | 2.63 tons |
| 600 lbs | 18.0 lbs | 2.5 lbs | 540 lbs | 3.29 tons |
Herd Size Feed Budgets for Pig (Sow/Boar)
Planning feed purchases and storage requires estimating total feed needs for your herd over time. The table below shows monthly and annual feed requirements and costs for various herd sizes of pig (sow/boar) at maintenance level using grass hay at $150/ton.
| Head Count | Daily DMI Total | Monthly Feed | Annual Feed | Annual Cost |
|---|---|---|---|---|
| 5 | 60.0 lbs | 0.90 tons | 10.95 tons | $1,866.48 |
| 10 | 120.0 lbs | 1.80 tons | 21.90 tons | $3,732.95 |
| 25 | 300.0 lbs | 4.50 tons | 54.75 tons | $9,332.39 |
| 50 | 600.0 lbs | 9.00 tons | 109.50 tons | $18,664.77 |
| 100 | 1,200.0 lbs | 18.00 tons | 219.00 tons | $37,329.55 |
| 200 | 2,400.0 lbs | 36.00 tons | 438.00 tons | $74,659.09 |
Other Animals
Browse feed requirement guides for other livestock species.