Selenium yeast in poultry production

From Ghislaine Roch (Canada) presentation at Lallemand’s International Selenium yeast seminar (Grenaa, Denmark, 2007)


Ghislaine Roch, independent feed nutritionist in Canada, has been working on antioxidants in animal production for over ten years. In Grenaa’s seminar, she stressed the importance of antioxidants in poultry management, explaining how modern animal production practices, associated with stress factors and intense metabolism, cause an increase in free radicals production, leading to lower performances, health problems as well as decreased quality of end products (meat and eggs).

Ghislaine Roch runs a poultry research farm in Canada, where she has conducted several studies with Alkosel®R397 vs. inorganic selenium, describing positive effects of the organic selenium source on:

1. Performance: average weight gain and feed conversion ratio are improved,
2. Skin elasticity and feathering (cellulitis prevention)

She also reported additional evidences that selenium yeast supplementation in broiler breeders and in layers improves hatchability, eggs quality (color) and antioxidative properties: selenium content, Vitamin E content and GSH-Px (glutathione peroxidase) enzymatic activity are increased.


Improving zootechnical performance

This trial was performed on 672 broilers, in three groups, from day 0 to slaughter (5 weeks).

Alkosel®R397 improved overall average daily weight gain when compared to selenite. This effect was statistically significant in the last week of the trial (106.6 g vs. 99.6 g). Overall feed conversion rate and slaughter weight were also significantly improved with Alkosel®R397, compared to inorganic selenium (1,546 vs 1,684), offering the producer a good return on investment.




Graph 1: Selenium yeast improves average daily weight gain in broilers compared to selenite.



Enhanced maternal immune transfer

In another study (Venne, 2003), broiler breeders were supplemented with Selenite or Alkosel®R397 between weeks 20-35, and antibody against several diseases were measured in the broilers.



Graph 2: Alkosel®R397 in broiler breeders diet offers better chicks protection against infectious Bursal disease and Reovirus



It appears that for two of the pathogens tested, infectious Bursal disease and Reovirus, Alkosel®R397 supplementation allowed a better maternal immunity transfer, with a 20 to 25% increase in the antibody titer, offering a better protection to the chicks and increased liveability for the first 10 days.


Improved fertility

A fertility study was performed in Portugal in 2004, on 520 cockerels, during 4 months. When compared to selenite, Alkosel®R397 improved males fertility, with an increase of 4.2% in the number of saleable chicks.




Graph 3: Alkosel®R397 increases males fertility



Improved eggs quality

Alkosel®R397 supplementation in layer hens increases eggs selenium content, compared to equivalent doses of selenite, due to the higher bioavailability of organic selenium. In a trial performed in 2003, G. Roch obtained a 92% increase in egg selenium content with Alkosel®R397.




Graph 4: Alkosel®R397 improves eggs selenium content.



The benefits are very wide: from the consumer, for which selenium status is generally too low (link human part), to reproducing flocks, for improving chicks’ antioxidant status.

It has recently been demonstrated that there is a linear correlation between the amount of selenium yeast in the diet and the eggs selenium content.


Safety

Finally, Ghislaine Roch presented a trial in broilers with high dose of selenium yeast (5 ppm), showing a significant improvement of performance (FCR and slaughter weight), and a significant increase of the animals’ blood, liver and muscle selenium content. She insisted that equivalent dose of selenium in its mineral form would be highly toxic. The lack of toxicity of high selenium yeast dosage is another important argument in favor of selenium yeast.

Ghislaine Roch concluded that selenium yeast was the most bioavailable, less toxic source of selenium to be used in poultry diet. It does contribute to improve growth performance in commercial conditions and appears to reduce the impact of stress in commercial farming, lowering mortality rates and improving flock uniformity. By improving eggs selenium status, selenium yeast Alkosel®R397 can also play a role in improving eggs nutritive value and quality for consumers.


Key points:

• Modern production practices lead to anti-oxidant deficiency in poultry.
• Organic selenium (Selenium yeast) is more bioavailable that inorganic selenium.
• Selenium yeast supplementation improves broilers, breeders and layers zootechnical performances.
• Selenium yeast supplementation increases resistance to cellulitis and improves maternal immune transfer.
• Selenium yeast supplementation improves fertility and hatchability.
• Selenium yeast supplementation increases eggs selenium content and improves eggs conservation.