Fat Supplement (Bypass Fat) — Livestock Feed Analysis
Bypass fat supplements (calcium salts of fatty acids or prilled fats) provide concentrated energy at 180% TDN on a dry matter basis, more than twice the energy density of corn. These products are designed to pass through the rumen without affecting fiber digestion or microbial populations, then be absorbed in the small intestine as fatty acids. Bypass fats are primarily used in dairy cow diets to increase energy density without increasing starch intake, which would depress milk fat percentage. Feeding rates are typically 0.5-1.0 lbs per cow per day, adding 2-4 Mcal of net energy to the diet. Fat supplements are also used for performance horses, show cattle being fitted for competition, and any animal requiring additional energy without increased feed volume. The TDN value exceeding 100% reflects the high caloric density of fat (9 kcal/gram) compared to carbohydrates (4 kcal/gram).
Which Animals Can Fat Supplement (Bypass Fat) Feed?
The table below shows how Fat Supplement (Bypass Fat) performs as a sole feed source for each of the 20 livestock species in our database. At 0% crude protein and 180% TDN, this feed meets the protein requirement for animals needing up to 0% CP and the energy requirement for animals needing up to 180% TDN. In practice, feeds are rarely used as the sole source; this analysis helps determine where fat supplement (bypass fat) fits in a mixed ration.
| Animal | Needs CP | Needs TDN | As-Fed/Day | CP Met? | TDN Met? | Monthly Cost |
|---|---|---|---|---|---|---|
| Beef Cow | 7% | 52% | 24.2 lbs | No | Yes | $363.64 |
| Dairy Cow | 16% | 70% | 49.5 lbs | No | Yes | $742.42 |
| Horse | 10% | 55% | 22.2 lbs | No | Yes | $333.33 |
| Meat Goat | 10% | 55% | 5.3 lbs | No | Yes | $79.55 |
| Dairy Goat | 14% | 65% | 6.1 lbs | No | Yes | $90.91 |
| Sheep | 10% | 55% | 5.3 lbs | No | Yes | $79.55 |
| Pig (Sow/Boar) | 14% | 75% | 12.1 lbs | No | Yes | $181.82 |
| Pig (Grower/Finisher) | 16% | 80% | 7.6 lbs | No | Yes | $113.64 |
| Chicken (Layer) | 16% | 70% | 0.2 lbs | No | Yes | $3.03 |
| Chicken (Broiler) | 20% | 78% | 0.3 lbs | No | Yes | $4.55 |
| Turkey | 22% | 75% | 0.9 lbs | No | Yes | $13.26 |
| Duck | 16% | 70% | 0.3 lbs | No | Yes | $4.77 |
| Rabbit | 16% | 65% | 0.3 lbs | No | Yes | $4.24 |
| Llama | 10% | 55% | 6.4 lbs | No | Yes | $95.45 |
| Alpaca | 10% | 55% | 2.7 lbs | No | Yes | $40.91 |
| Donkey | 8% | 50% | 7.6 lbs | No | Yes | $113.64 |
| Bison | 7% | 52% | 36.4 lbs | No | Yes | $545.45 |
| Elk | 12% | 60% | 20.2 lbs | No | Yes | $303.03 |
| White-tailed Deer | 12% | 60% | 5.0 lbs | No | Yes | $75.76 |
| Miniature Horse | 10% | 55% | 6.1 lbs | No | Yes | $90.91 |
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 Fat Supplement (Bypass Fat) with other feeds in the supplement 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 |
| Whole Corn | 88% | 9% | 88% | $220 | $250 |
| Mineral Supplement | 98% | 0% | 0% | $800 | $816 |
| Salt Block | 100% | 0% | 0% | $300 | $300 |
| Kelp Meal | 90% | 6% | 45% | $1200 | $1333 |
| Fat Supplement (Bypass Fat) | 99% | 0% | 180% | $1000 | $1010 |
| Urea (Feed Grade) | 99% | 281% | 0% | $500 | $505 |
Feeding Guidelines for Fat Supplement (Bypass Fat)
When incorporating fat supplement (bypass fat) into a livestock feeding program, consider the following nutritional characteristics. With a dry matter content of 99%, each pound of as-fed fat supplement (bypass fat) provides 0.99 lbs of actual dry matter. The crude protein content of 0% means that each pound of dry matter delivers 0.0 grams of crude protein. The TDN content of 180% indicates the proportion of the feed that is digestible and available for energy.
The cost of fat supplement (bypass fat) at $1000 per ton translates to $0.500 per pound as-fed or $0.505 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.