Chicken business is under added pressure to deliver high quality eggs and meat, as well as meeting consumers' needs for natural, safe, and environmentally safe feed additives. Synthetic colorants and chemical antioxidants have long been used to increase egg yolk coloration, poultry skin coloration, and bird health, but they are falling out of favor as they are also a safety issue as much as consumers tending to favor natural sources.
This has stimulated increasing interest in astaxanthin, a dietary carotenoid pigment that is a potent antioxidant. Famous for imparting salmon, shrimp, and flamingos their pink-orange color, astaxanthin is currently also under intense testing for use in animal feed. But farmers and feed producers ask one question: Is astaxanthin safe to use in poultry feed?
This article discusses what astaxanthin is, its use in poultry feed, its advantages to egg and meat quality, and the science behind its safety.
What is Astaxanthin?
Astaxanthin is a natural carotenoid pigment which occurs in microalgae (Haematococcus pluvialis), red yeast (Xanthophyllomyces dendrorhous), krill, and crustacean shells. It is a member of the xanthophyll group of carotenoids and one of nature's most potent antioxidants.
In contrast to all other carotenoids, astaxanthin is not metabolized to vitamin A but instead has direct health-promoting activities. In poultry, it is supplemented in feed for two reasons:
- Pigmentation – increasing pigmentation of yolk, skin, and shanks.
- Health benefits – enhancing immunity, reducing oxidative stress, and enhancing reproductive performance.
Why Use Astaxanthin in Poultry Feed?
1. Improved Egg Yolk Pigmentation
Pigmentation of egg yolks is a key consumer quality trait. Yolks of astaxanthin-fed laying hens are more yellow-orange, a trait that will most probably be identified with freshness and nutritional value. Natural astaxanthin gives colour, as compared to synthetic pigments, and also imparts health benefits to the birds.
2. Antioxidant Protection
Astaxanthin has been found to be as powerful as 6000 times vitamin C and considerably more potent than vitamin E in antioxidant activity (Hussein et al., 2006). Oxidative damage in poultry is harmful to fertility, growth, immunity, and meat quality. Astaxanthin, by inhibiting oxidative damage, protects meat, egg, and tissue from lipid peroxidation.
3. Immune Support
It has been proven through studies that supplementing with astaxanthin improves immune performance in poultry, increasing disease and stress resistance
4. Improved Meat Quality and Shelf Life
Oxidation is among the primary causes of meat quality decline. Birds that are fed astaxanthin exhibit lower oxidative rancidity in muscle tissue, resulting in longer shelf life and more acceptable meat
5. Reproductive Health
Astaxanthin was found to enhance fertility of breeding hens and cocks by antioxidant protection of reproductive cells against oxidative damage
Safety of Astaxanthin in Poultry Feed
1. No Toxic Side Effects Reported
Several trials with poultry have shown that astaxanthin supplementation is not toxic, causing no unfavorable side effects to feed consumption, growth rate, egg laying, and general health. Birds may be safely fed on diets containing natural astaxanthin at suitable inclusion levels.
2. Regulatory Approvals
- European Food Safety Authority (EFSA): Authorized astaxanthin as a feed additive in poultry, aquaculture, and companion animals at particular inclusion levels.
- U.S. Food and Drug Administration (FDA): Acknowledges natural astaxanthin from Haematococcus pluvialis as Generally Recognized as Safe (GRAS) for food and feed uses.
3. Human Consumption Safety
Astaxanthin residues that are deposited in meat and eggs are safe for human use. Indeed, astaxanthin is also marketed as a dietary supplement for human beings with acceptable safety for consumption up to 12 mg daily (EFSA, 2014).
4. Poultry Dosage Recommendation
A trial demonstrates 20–80 mg/kg of feed supplementation levels are adequate for pigmentation and health. Anything higher is not usually required and not cost-effective, but still safe.
Evidence Supporting Safety
- Egg Pigmentation Study: Sun et al. (2012) reported that astaxanthin supplementation of laying hens promoted yolk colour scores considerably without having any negative impact on health.
- Broiler Health Study: Zhang et al. (2011) observed enhanced antioxidant enzyme activity and immune response in broilers that received astaxanthin-supplemented diets.
- Reproductive Performance: Nishigaki et al. (2008) demonstrated that fertility in breeder chickens was increased with astaxanthin supplementation by safeguarding the sperm and egg cells against oxidative stress.
- Meat Quality: Akiba et al. (2001) found that birds fed astaxanthin showed lower levels of lipid peroxidation in broiler meat, affirming its function in ensuring meat shelf life.
Limitations and Considerations
Although safe, farmers need to take the following into consideration:
- Cost: Natural astaxanthin is costlier than synthetic pigments, though prices are slowly decreasing.
- Source Quality: Effectiveness and safety are source-dependent. Algal astaxanthin is superior to synthetic astaxanthin based on its high antioxidant potency.
- Adequate Dosage: Supra-supplementation is devoid of likely toxicity but could be economically inefficient.
Conclusion
So, is astaxanthin safe for animal feed applications? The science and regulation firmly affirm the affirmative. Astaxanthin is not just safe but actually highly advantageous. It enhances the yolk color of eggs, enhances immune function, enhances reproductive performance, and preserves meat quality-nearly all this at natural and consumer-acceptable cost.
For broiler manufacturers looking to minimize dependence on synthetic additives, astaxanthin is a robust and environmentally friendly solution. With the use of natural feed additives such as astaxanthin, the poultry industry can respond to consumers' calls for healthier, safer, and more natural animal food products.
References
Akiba, Y., Sato, K., Takahashi, K., Matsushita, K., Komiyama, H., Tsunekawa, H., & Nagao, H. (2001). Meat color modification in broiler chickens by feeding yeast Phaffia rhodozyma containing high concentrations of astaxanthin. Japanese Poultry Science, 38(1), 36–43.
Christaki, E., Karatzia, M. A., & Florou-Paneri, P. (2013). The use of natural carotenoids in animal nutrition: Current knowledge and future directions. Animal Feed Science and Technology, 197, 1–11.
EFSA (European Food Safety Authority). (2014). Scientific Opinion on the safety of astaxanthin for the target species, consumer and environment. EFSA Journal, 12(7), 3724.
Hussein, G., Sankawa, U., Goto, H., Matsumoto, K., & Watanabe, H. (2006). Astaxanthin, a carotenoid with potential in human health and nutrition. Journal of Natural Products, 69(3), 443–449.
Nishigaki, T., Itoh, T., & Amano, T. (2008). Astaxanthin as a nutritional supplement in poultry reproduction. Reproductive Biology and Endocrinology, 6, 35.
Sun, Z., Liu, J., Zeng, X., Huangfu, J., & Wang, Y. (2012). The effect of dietary astaxanthin supplementation on egg yolk pigmentation and antioxidant capacity in laying hens. Poultry Science, 91(8), 2069–2075.
Zhang, J., Sun, Z., Sun, P., Chen, T., & Qian, H. (2011). Effect of astaxanthin-rich microalgae on growth performance and antioxidant capacity in broilers. Animal Science Journal, 82(5), 734–739.
