Benefits beyond growth: How methionine levels, sources boost poultry health

Essential amino acid methionine delivers antioxidants, and resilience to heat stress and immune challenges.

DL-methionine, an essential amino acid in dry form with 99% purity, is known for promoting growth in poultry and livestock production. However, the supplement brings additional benefits to live production, the feed manufacturer and the nutritionist.

Dr. Victor Naranjo, Evonik's technical services director for the Americas, joined the Chat to highlight several lesser known benefits of DL-methionine for animal health and nutrition. 

Transcription of Feed Strategy Chat with Dr. Victor Naranjo, technical services director – Americas, Evonik

Jackie Roembke, editor in chief, WATT Feed Brands and Feed Strategy: Hi, everyone. Welcome to Feed Strategy Chat. I’m your host, Jackie Roembke, editor in chief of WATT Feed Brands and Feed Strategy magazine.

This edition of Feed Strategy Chat is brought to you by Evonik, a global provider of science-driven products and services for the sustainable and efficient production of meat, fish, eggs and milk.

Today’s poultry and livestock producers are under pressure to boost performance while maximizing their productivity and profitability. One key way to achieve this is to correctly supplement and use the best amino acid sources on the market. Evonik’s MetAMINO ensures an adequate supply of sulfur amino acids — particularly the essential methionine. Livestock producers who use MetAMINO can achieve not just better, but the best, results in animal health and productivity.

Today we’re joined by Dr. Victor Naranjo, Evonik’s technical services director for the Americas region. He’s here today to examine how methionine levels and sources can enhance poultry and livestock production beyond an animal’s growth.

Hi Dr. Naranjo, how are you today?

Dr. Victor Naranjo, technical services director – Americas, Evonik: Hello, Jackie. Very good. Thank you for the invitation. It's a pleasure to be here.

Roembke: Thank you for participating. Well, let's get right into it. Please explain the difference between DL-methionine and methionine hydroxy analogs or MHA.

Naranjo: Yes. DL-methionine and liquid methionine hydroxy analog (MHA) are both supplemental sources that are commonly used to help nutritionists to precisely meet the sulfur amino acid requirements in poultry diets. The differences are that DL-methionine is a dry product with 99% purity of DL-methionine, and liquid MHA contains 12% water and 88% concentration of DL-MHA. From a chemical point of view, that brings us a difference in which the DL-methionine is amino acid per definition with a racemic mixture of DL-methionine; and liquid MHA is an organic acid, as it contains a hydroxy group instead of an amino group. Therefore, animals need to convert that hydroxy analog component into the utilizable form of L-methionine.

Because of these differences, MHA products are absorbed through different ways, which are less efficient than the DL-M resulting in a slower reduced intestinal absorption, greater microbial degradation and also overall reduced utilization, compared to DL-methionine, which is well established to be 100% bioavailable to the animal.

Roembke: Does one of these methionine sources exhibit better antioxidant function than the other?

Naranjo: Yeah, this is a very interesting point, Jackie. And first of all, it's very important to mention that oxidative stress is certainly a relevant challenge in animal production and this part is triggered by different stressors, such as heat stress, stocking density, different metabolic dysfunctions, dietary insufficiencies — among different factors.

Methionine, besides serving as an essential amino acid in building block for protein deposition and feathering, it is also critical for methyl donor for DNA methylation and also a key precursor for the synthesis of glutathione and taurine, which are important molecules involved in the antioxidant and immune function.

It is well documented that this deficiency of methionine plus cysteine levels impair immune function and antioxidant capacity of the birds. Recent trials have confirmed that the antioxidant capacity and these immune response parameters can be significantly improved when we increase the levels of DL-methionine or methionine plus cysteine levels. But, interestingly, no additional benefits or differences are obtained when using liquid D-MHA or in the conversion of these antioxidant products as it has been claimed. On the contrary, some recent literature has demonstrated that, at cellular level, the conversion of the MHA to L-methionine, which is the utilizable form by the animal, resulted in higher concentration of H202 that is a strong reactive oxygen species (ROS). This indicated that the metabolism of MHA may even add some oxidative stress at cellular level.

Roembke: Beyond the antioxidant properties that you just mentioned, what are the other benefits of supplementing with DL-methionine?

Naranjo: DL-methionine, as mentioned before, is a source that is 100% bioavailable to the animal. As a powder, it also has excellent handling properties to be managed in the feed mill. There are no scientific doubt or debates about the utilization to the animal or its easiness of application at the feed mill level.

Therefore, the use of DLM allows practical nutritionists to precisely meet their specific needs of methionine plus cysteine. This translates into the most cost-effective approach to fully guarantee and monitor your optimal methionine plus cysteine levels to optimize and maximize your performance, health and feathering conditions under different production and challenge conditions.

Roembke: You just pointed out some very interesting attributes. To take it a step further, is there recent or ongoing research related to methionine and its effects on animal health and performance? And if so, could you discuss those findings?

Naranjo: Yes, for Evonik, methionine continues to be one of the most important topics to be part of our research projects. We are continuously evaluating the optimal levels of methionine plus cysteine and the impact of methionine sources on growth performance, carcass yields, and immune parameters, and the effects of the sources on their different production and challenge conditions.

Recently, for example, colleagues in United States completed a practical trial validating the impact of replacing 100 parts of MHA products with 65 parts of the DL-methionine — or in other words, applying scientifically the derived bio-efficacy value of 65% of MHA — at two different levels of crude protein, which is a current trend and need in the industry.

In this study, the replacement proportion of 100 to 65, MHA to DLM, did not affect body weight gain or feed conversion ratio, but we found potential to improve meat yield when using DL-methionine, which was an indication of greater absorption or utilization of DLM compared to MHA at these doses of specific methionine plus cysteine levels.

For us, this is a very important topic that we are continuously evaluating and also summarizing all of these research results into our MetAMINO ATLAS and more recently in MetAMINO Calculator where different users can calculate the benefits of using DLM compared to liquid MHA for their formulation, feed mill and the procurement part.

Again, our main approach is to determine the optimal levels of methionine plus cysteine to improve the performance health and the feathering conditions in poultry production.

Roembke: Excellent. Thank you so much for those insights and that information. For more information on Evonik and MetAMINO, please visit

Thank you so much, Dr. Naranjo, and thanks to you for tuning in.