The importance of this difference in terms of quantity can be shown by determining percentage of absorption of complete and intact fats, monoglycerides and fatty acid.

Several fatty acids have been identified that have adverse effects on poultry health or performance: 1. Cyclopropane (CPFA), that have a propene ring in their carbon chain. 2. Erosic acid (docosnoic acid) is an important fatly acid in turnip and mustard meal. The amount of uric acid in turnip meal in the older varieties such as Brassica campestris and Brassics napus varies from 25%-45%

The digestibility of fats is affected by the following factors:

• Length of fatty acid chain
• Number of double bonds in fatty acid
• The presence or absence of liner bond (in fact, fat is in form of triglycerides or free fatty acid)
• Saturated and unsaturated fatty acid on glycerol of one triglyceride molecule
• Chicken age
• Ratio of unsaturated to saturated fatty acid in mixture of free fatty acids.
• Intestinal microbial
• Dietary composition
• Amount and types of triglycerides that are mixed with fats.

The balance of saturated fatty acid and unsaturated in diets and bile salt secreted are important factors in the absoption of poultry fat.