In the quest to enhance poultry production and egg quality, researchers have long explored the benefits of selenium, a trace mineral crucial for various biological functions. A recent study led by Jianmin Zhou from the Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Institute of Feed Research, China Academy of Agricultural Sciences, has shed new light on the comparative effects of selenium-enriched yeast (SeY) and selenium-enriched lactobacilli (SeL) on laying hens. The findings, published in the Journal of Animal Science and Biotechnology, offer intriguing insights into the future of poultry nutrition and gut health.
The study, which involved 450 Hy-Line Brown laying hens, compared the impacts of different selenium sources on egg quality, antioxidant capacity, selenium deposition, and gut health. After a two-week pre-treatment with a selenium-deficient diet, the hens were divided into five groups, each receiving varying levels of selenium from either SeY or SeL. The results were striking.
Both SeY and SeL showed promising effects on feed efficiency and egg quality. “SeY15 and SeL15 improved the feed-to-egg ratio in the latter stages of the trial,” Zhou noted, highlighting the potential for these supplements to enhance productivity. Moreover, SeY15 and SeL30 significantly increased Haugh units, a measure of egg albumen quality, while SeY15, SeL15, and SeL60 resulted in darker yolk color, a trait often preferred by consumers.
The study also revealed that all selenium-supplemented diets increased selenium content in whole eggs, albumen, and yolk, with SeL groups showing a dose-dependent effect. This is a significant finding for the poultry industry, as it demonstrates the potential to enhance the nutritional value of eggs through dietary supplementation.
Antioxidant enzyme activities increased, and malondialdehyde (MDA) content decreased in the serum of hens receiving selenium supplements, with SeY15 showing the highest glutathione peroxidase (GSH-Px) levels. This suggests that selenium supplementation can boost the antioxidant capacity of laying hens, potentially leading to improved overall health and productivity.
However, the study also uncovered some potential drawbacks. High levels of SeL (6.0 mg Se/kg) increased serum alkaline phosphatase and aspartate transaminase, and distorted liver architecture. This indicates that while selenium is beneficial, excessive amounts can have adverse effects on metabolic functions.
The research also delved into the impact of selenium on gut health. SeL15 improved the ileal villus height-to-crypt depth ratio, a key indicator of intestinal health. Additionally, SeY15 and SeL15 altered the expression of genes involved in selenium metabolism and antioxidant defense in the liver. Interestingly, SeY15 altered ileal microbiota by increasing both beneficial and pathogenic bacteria, whereas SeL15 predominantly boosted beneficial bacteria.
These findings suggest that SeL integrates the antioxidant properties of organic selenium with the probiotic benefits on gut health, resulting in a performance-enhancing effect comparable to that of SeY. However, high SeL levels compromised productivity and metabolic functions while enhancing selenium deposition.
The implications of this research are far-reaching. As the demand for high-quality, nutrient-dense eggs continues to grow, the poultry industry is under pressure to optimize production methods. The findings from this study could pave the way for more targeted and effective use of selenium supplements, leading to improved egg quality, enhanced feed efficiency, and better overall health for laying hens.
The study, published in the Journal of Animal Science and Biotechnology, provides a comprehensive analysis of the effects of selenium-enriched yeast and lactobacilli on laying hens. As the poultry industry continues to evolve, these insights could shape future developments in feed formulation and nutritional strategies, ultimately benefiting both producers and consumers.