Increasing the level of fat in animal diets can be done by using liquid sources of fat, such as fish or vegetable oils.
In the case of ruminant animals these liquid fat forms can cause problems in the rumen, particularly with feed digestibility, thereby reducing animal performance.
Dry feed fats typically pass through the rumen for digestion in the small intestine and not in the rumen. This is why they are also called “rumen-protected” or “bypass” fats.
By supplying energy in rumen by-pass form, fats can improve animal performance and general health, leading to increased milk production and improved fertility.
There are two major types of commercially available dry feed fats:
1) calcium soaps of fatty acids
2) hardened or hydrogenated fats.
Calcium soaps can be manufactured from any fatty acids but the most common are based on palm fatty acids. They are produced by reacting fatty acids with calcium to produce a rumen-insoluble fat-source that passes unchanged through the rumen to the small intestine for digestion.