Corn Silage — Livestock Feed Analysis
Corn silage is the highest-energy forage in livestock production, providing 70% TDN on a dry matter basis with moderate protein (8%). The low dry matter content (35%) means that livestock must consume large volumes of as-fed silage to meet their dry matter needs. Corn silage is a staple of dairy and beef feedlot rations, providing both the fiber and energy components in a single feed. The cost per ton of as-fed corn silage ($50) is low, but the cost per ton of dry matter ($143) is more comparable to hay when adjusted for moisture. Proper ensiling in bunkers, bags, or uprights requires rapid filling, good packing, and airtight sealing to achieve the anaerobic fermentation that preserves nutrients. Corn silage is not suitable for horses due to the risk of mold and mycotoxin contamination in fermented feeds.
Which Animals Can Corn Silage Feed?
The table below shows how Corn Silage performs as a sole feed source for each of the 20 livestock species in our database. At 8% crude protein and 70% TDN, this feed meets the protein requirement for animals needing up to 8% CP and the energy requirement for animals needing up to 70% TDN. In practice, feeds are rarely used as the sole source; this analysis helps determine where corn silage fits in a mixed ration.
| Animal | Needs CP | Needs TDN | As-Fed/Day | CP Met? | TDN Met? | Monthly Cost |
|---|---|---|---|---|---|---|
| Beef Cow | 7% | 52% | 68.6 lbs | Yes | Yes | $51.43 |
| Dairy Cow | 16% | 70% | 140.0 lbs | No | Yes | $105.00 |
| Horse | 10% | 55% | 62.9 lbs | No | Yes | $47.14 |
| Meat Goat | 10% | 55% | 15.0 lbs | No | Yes | $11.25 |
| Dairy Goat | 14% | 65% | 17.1 lbs | No | Yes | $12.86 |
| Sheep | 10% | 55% | 15.0 lbs | No | Yes | $11.25 |
| Pig (Sow/Boar) | 14% | 75% | 34.3 lbs | No | No | $25.71 |
| Pig (Grower/Finisher) | 16% | 80% | 21.4 lbs | No | No | $16.07 |
| Chicken (Layer) | 16% | 70% | 0.6 lbs | No | Yes | $0.43 |
| Chicken (Broiler) | 20% | 78% | 0.9 lbs | No | No | $0.64 |
| Turkey | 22% | 75% | 2.5 lbs | No | No | $1.88 |
| Duck | 16% | 70% | 0.9 lbs | No | Yes | $0.68 |
| Rabbit | 16% | 65% | 0.8 lbs | No | Yes | $0.60 |
| Llama | 10% | 55% | 18.0 lbs | No | Yes | $13.50 |
| Alpaca | 10% | 55% | 7.7 lbs | No | Yes | $5.79 |
| Donkey | 8% | 50% | 21.4 lbs | Yes | Yes | $16.07 |
| Bison | 7% | 52% | 102.9 lbs | Yes | Yes | $77.14 |
| Elk | 12% | 60% | 57.1 lbs | No | Yes | $42.86 |
| White-tailed Deer | 12% | 60% | 14.3 lbs | No | Yes | $10.71 |
| Miniature Horse | 10% | 55% | 17.1 lbs | No | Yes | $12.86 |
Cost Comparison with Similar Feeds
Selecting the most cost-effective feed requires comparing both the as-fed price and the price per ton of dry matter. The table below compares Corn Silage with other feeds in the silage category and common reference feeds. The cost per ton of dry matter accounts for moisture content, providing a fair comparison between feeds with different moisture levels.
| Feed | DM % | CP % | TDN % | $/Ton | $/Ton DM |
|---|---|---|---|---|---|
| Grass Hay | 88% | 8% | 52% | $150 | $170 |
| Alfalfa Hay | 90% | 18% | 58% | $250 | $278 |
| Corn Silage | 35% | 8% | 70% | $50 | $143 |
| Haylage (Baleage) | 45% | 14% | 60% | $80 | $178 |
| Whole Corn | 88% | 9% | 88% | $220 | $250 |
Feeding Guidelines for Corn Silage
When incorporating corn silage into a livestock feeding program, consider the following nutritional characteristics. With a dry matter content of 35%, each pound of as-fed corn silage provides 0.35 lbs of actual dry matter. The crude protein content of 8% means that each pound of dry matter delivers 1.3 grams of crude protein. The TDN content of 70% indicates the proportion of the feed that is digestible and available for energy.
The cost of corn silage at $50 per ton translates to $0.025 per pound as-fed or $0.071 per pound of dry matter. When evaluating whether to use this feed, compare the cost per unit of the nutrient you are trying to supply. If you need protein, calculate the cost per pound of crude protein. If you need energy, calculate the cost per unit of TDN. The most economical feed choice depends on which nutrient is the limiting factor in your ration and the relative prices of available feeds in your local market.
Storage requirements vary by feed type and moisture content. Feeds with less than 15% moisture (most dry hays and grains) can be stored in open-sided barns or covered stacks for months to years without significant nutrient loss. Feeds with higher moisture content require either airtight storage (silage, haylage) or must be consumed within days of delivery (wet brewers grains, wet distillers grains). Proper storage prevents mold growth, mycotoxin contamination, and dry matter losses that can significantly increase the effective cost per unit of nutrition delivered to the animal.
Always introduce new feeds gradually over a period of 7-14 days, increasing the proportion of the new feed while decreasing the old feed by equal amounts each day. Sudden dietary changes disrupt the microbial population in the rumen (for ruminants) or the hindgut (for horses), potentially causing digestive disturbances ranging from mild loose stools to life-threatening acidosis or colic. This gradual transition is especially important when switching between forages and concentrates, or when introducing high-starch feeds like corn or barley to animals previously consuming an all-forage diet.
Other Feed Types
Compare nutritional profiles and costs for all livestock feeds in our database.