Interpretive Summary: Evaluation of lipid sources and emulsifier addition on fat digestion of yellow-feathered broilers
By: Xiaomeng Ye, Yao Yu, Jiang Chen, Yi Zou, Songbai Liu, Huize Tan, Feng Zhao, Yuming Wang
Considering that commercial diets generally contain 3% to 8% added lipids to provide up to 20% metabolizable energy (ME) in broiler diets, the addition of emulsifier in diets was believed to improve the digestibility of fat. In this experiment, seven sources of lipid with or without emulsifier addition were evaluated for ME in yellow-feathered broilers. Without emulsifier addition, ME values were observed highest for cottonseed oil [4,129 kcal/kg∙ dry matter (DM)] and lowest for rice bran oil (4,036 kcal/kg∙DM) and lard (4,015 kcal/kg∙DM). With emulsifier addition, ME values were highest for soybean oil (4,177 kcal/kg∙DM) and lowest for modified palm oil (4,059 kcal/kg∙DM) and lard (4,024 kcal/kg∙DM). The emulsifier has a positive effect on the ME of rice bran oil, but the ME of cottonseed oil and modified palm oil declines with the addition of emulsifiers. These inconsistent results may be influenced by the relationship between ME and concentration of fatty acids across sources of dietary lipids. Lipids with high concentrations of unsaturated fatty acids are more easily emulsified and better digested than those rich in saturated fatty acids. Additionally, the concentration of C18:0 and C18:1 in lipids contributed to the main variance of ME prediction equation.
Read the full article on the Journal of Animal Science.