Hello everyone! Welcome to my Research Digest #10.
Today's article is titled 'Effects of dietary supplemental bile acids on performance, carcass characteristics, serum lipid metabolites and intestinal enzyme activities of broiler chickens'.
This is a work from Dr. Liying Zhang's lab from China Agricultural University. The paper came out on Poultry Science in 2018.
We know that lipid digestion and absorption in the animals can only be completed with the help of bile salts. As the major components in bile salts, bile acids are the synthesized from cholesterol in the liver and consists of a mixture of individual bile acids (such as cholic acid, deoxycholic acid, chenodeoxycholic acid, etc). They act as an emulsifier to breakdown big lipid globules into smaller droplets, while activate lipase to then digest the lipids into fatty acids and monoglycerides. After digestion, bile salts are also needed to form micelles to facilitate lipid absorption into the enterocytes.
In recently years, exogenous lipase became an approach to enhance lipid utilization in poultry. Yet without the help of bile salts (or emulsifiers in general), lipid utilization still could not be optimized, especially in young birds whose lipid utilization is restricted because of limited endogenous bile salts production.
So, would an exogenous bile acids supplement help with enhancing nutrient utilization and therefore improve performance in broilers?
That is the question the authors wanted to answer.
What was done?
Very straight-forward experimental design as shown below.
The bile acids supplement is from Lachance Animal Health.
Note that the supplement contains 30% of bile acids. In the manuscript, the concentrations shown were pure bile acids (40, 60, and 80 mg/kg), here, I have converted them back to the product concentrations.
What was found?
The results were pretty consistent where both 188 and 250 mg/kg Bile Acids supplementation were effective in improving the following measurements.
- Growth Performance: Improved 42d ADG and FCR ---- FCR was reduced by 4 to 5 points.
- Carcass Quality: Improved relative carcass weight by 2.8%, eviscerated weight by 3.3%, leg weight by 2.5%, while reducing abdominal fat.
- Lipase activity: where lipase and lipoprotein lipase activity were significantly enhanced by 67-69%, respectively.
The activity of hormone sensitive lipase was reduced here by 188 and 250 bile acids supplementation --- HSL is an intracellular neutral lipase and is activated when the body needs energy generated from lipid mobilization, thus according to the authors, this reduction "suggests that bile acids are improving the efficiency of fat digestion and absorption, thus decreasing the level of needed dietary fat."
Take home message
✅ 188 - 250 mg/kg exogenous bile acids supplementation could effectively improve lipase activity, growth performance, and carcass quality in broilers.
Full Article Access 👇
Wenqing Lai, Weigang Huang, Bing Dong, Aizhi Cao, Wenjuan Zhang, Juntao Li, Hui Wu, Liying Zhang, Effects of dietary supplemental bile acids on performance, carcass characteristics, serum lipid metabolites and intestinal enzyme activities of broiler chickens, Poultry Science, Volume 97, Issue 1, January 2018, Pages 196–202.