Feed fats – how to improve their nutritional value

Feed variability is one of the most important issues for animal production profitability.  When the diet density is variable, it becomes very difficult to predict the animal performance.

Vegetable oils and animal fats are among all the feed components that are usually added to the poultry diets, the ones that contribute the most to increase the dietary energy concentration and feed variability. This is particularly true when many different types of fats and oils are being offered to the feed mills, while in the past mainly soy oil and animal fat blends were available.

To reduce the impact of feed fats and oils on feed variability, two tools play a very important role:

1.        the correct evaluation of nutritional values of oils and fats

2.        the improvement of the digestibility rate of the fats and oils

 

The following figure shows the energy values (AME/kg) of different sources of fats and oils analyzed by Kemin, calculated with the Wiseman equation using parameters for broilers older than 21 days.

Figure 1. Energy values (AME/kg) of different sources of fats and oils

From the left to the right are 3 groups of lipid classes, the AME values are soy oil, acid oil and animal fats that are calculated on a pure fat and oil basis without considering the diluting effect of MIU (moisture, impurity and unsaponifiable) and NEM (non-elutable matter).

The AME values for acid oil and animal fats are characterized by a pronounced variability, particularly on acid oils and younger animals. Free fatty acid content (FFA), unsaturated: saturated ratio (U:S) as well as the oxidative status of lipids are the main variables playing a role on fats and oils digestibility and their variability.

The correct evaluation of nutritional values of oils and fats and the improvement of their digestibility rate play a very important role to reduce feed variability.

When accurate information on nutritional values of oils and fats is available, feed formulations are more precise and animal performance is consequently more consistent. The regular determination of oils and fats energy value by means of “in vivo” digestibility assays is complicated and involves a considerable amount of resources and costs. By measuring FFA content and U:S ratio values in the laboratory, AME values of relevant feed fats and oils can be calculated by the Wiseman equation which is well accepted and recommended by many authors.

Kemin implemented a new customer service, named Lipid Evaluation Test.   This test determines the AME value for young and adult animals, after FFA content and U:S ratio determination by evaluating  fats and oils samples and will also calculate the diluting effect of MIU and NEM on the nutritional value.

The effect of emulsifiers to improve the emulsification process is very well known, but the superior effect of LYSOFORTE® on the digestibility rate of lipids respect to phospholipids and synthetic emulsifier has been proven. The effect of LYSOFORTE on the digestibility rate of feed fats and oils is greater on fats and oils characterized by a lower digestibility rate. Based on numerous trials the effect of LYSOFORTE on energy improvement is clear on all the diets, however with  the supplementation of LYSOFORTE we have observed a clear effect in favor of Palm oil, that is characterized by a lower U:S ratio (more saturated FA) and consequently, by a lower digestibility rate. The addition of LYSOFORTE can decrease the energy gap between different diets, increasing the AME value of saturated oils based diets, like Palm oil.

LYSOFORTE Booster Dry was also tested in turkey diets based on acid oil, increasing the AME value of this by-product and recovering completely the energy gap of reformulated diet respect to positive control.

Trials were performed in piglets with LYSOFORTE Booster Dry added on top of the standard diets or added to reformulated diets (lowered energy). The addition of LYSOFORTE Booster Dry on top resulted in a clear improvement of animal performance, while the animals fed with reformulated diets were able to achieve the same or better performance with respect to the control.  These trials demonstrated the effectiveness of LYSOFORTE Booster Dry on improving the feed efficiency when used on top of feed and also in reformulation protocol.

Reformulation success and zootechnical results showed a significant improvement in economic results of the treatments groups (table 1).

Table  1.  Economic calculation

Conclusion

Feed fats and oils variability is very common and often under evaluated, which can influence feed variability and animal performance.

It is possible to alleviate the effect of fats and oils variability by means of a more precise AME evaluation, a precise analysis of lipids oxidative status and finally by increasing the digestibility rate of fats and oils by the addition of LYSOFORTE to the feed.

Kemin Internal Reference 14-00051, 08-00115, 13-00177, 14-00067