Adding taurine to the feed of laying hens in their later laying phase results in heavier eggs and better internal egg quality, without changing how much they eat or how often they lay.
Mechanism
Synthesis from 1 study
Taurine tells the hen's liver to make less cholesterol and get rid of more of it, so less cholesterol goes into the egg. At the same time, it increases healthy fats in the liver that get put into the yolk. This makes the egg bigger and the white thicker without changing how often the hen lays or...
Most probable mechanism
Taurine tells the liver to make less cholesterol and push more of it out as bile or store it as esters, so less cholesterol reaches the developing egg. At the same time, taurine increases the amount of healthy fats called polyunsaturated fatty acids in the liver, which get packed into the egg yolk instead. This makes the egg heavier and the white firmer without changing how often the hen lays or how much she eats.
Taurine enters hepatocytes and suppresses the expression of SREBP2, reducing transcriptional activation of cholesterol synthesis genes
Downregulation of HMGCR decreases the rate-limiting step in cholesterol biosynthesis, lowering hepatic cholesterol production
Taurine upregulates ABCG5, increasing cholesterol excretion into bile and reducing hepatic cholesterol pools
Taurine upregulates ACAT2, converting free cholesterol into cholesteryl esters for storage or lipoprotein packaging, reducing free cholesterol availability
At higher doses, taurine upregulates CYP7A1, accelerating cholesterol conversion to bile acids for intestinal excretion
Reduced hepatic cholesterol availability limits cholesterol transport via VLDL to the ovary, decreasing cholesterol deposition in egg yolk
Taurine increases hepatic production or reduces oxidation of polyunsaturated fatty acids, elevating circulating levels available for yolk uptake
During vitellogenesis, vitellogenin-bound polyunsaturated fatty acids are incorporated into the developing oocyte, increasing yolk PUFA content
Increased yolk polyunsaturated fatty acids and reduced cholesterol alter yolk physical properties, enhancing albumen viscosity and egg weight
Evidence from Studies
Supporting (1)
Community contributions welcome
Effects of dietary taurine supplementation on polyunsaturated fatty acids, cholesterol, and egg quality of egg of hens
Contradicting (0)
Community contributions welcome
Gold Standard Evidence Needed
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