Threonine key nutrient in lower protein broiler diets: researcher

There is a trend for lower crude protein (CP) diets in animal production in the Netherlands, says a poultry expert based at Schothorst Feed Research.

“Lowering dietary CP contributes to more sustainable broiler production, and is more cost effective,”​ said Laura Star, poultry nutrition researcher at that Dutch facility.

We caught up with her at a workshop run by Ajinomoto Eurolysine in conjunction with Altilis Animal Nutrition, on the sidelines of SPACE 2017 in France earlier this month.

Threonine is precursor for glycine ​

Star’s talk focused on the optimal levels of threonine that are required in reduced CP diets for broilers.

Threonine, she said, is able to spare the glycine requirement in low CP diets.

“Protein is an expensive nutrient. Lower CP levels is interesting for feed mills, it makes them more competitive.  On the other hand, [animal production] in the Netherlands is very high in nitrogen excretion, so also for that it is of interest to reduce nitrogen levels and you can do that by lowering the crude protein level in the diets.”​

“If you reduce your CP levels you have to be aware that the amino acids you supply are still at the right level. They should not be limiting as then you will be limiting the performance of the birds. That is valuable for all amino acids, but Threonine is particularly important in that it is a precursor for glycine, so if you go down in your CP levels, you will also go down in your glycine levels, and that might become limiting and then it is of interest to feed extra threonine in your diets.​

“Threonine is a key nutrient in gut health. It is important part of the mucus layer in the intestine. If a bird is infected, and has a damaged gut, if you feed extra threonine you will help the bird to increase its feed intake have better growth.”​

The Ajinomoto Eurolysine/Altilis event, which included presentations from academic as well as industry researchers, was targeted at feed manufacturers. It covered, among other topics, new insights into the optimal amino acids levels in lower CP diets, the impact of probiotics on the poultry gut microbiota and the benefits of incorporating capsaicin into broiler feeds.