Methionine is an essential amino acid needed for protein synthesis and growth of broilers. Different methionine sources are available on the market: DL-Methionine, OH-Methionine under liquid or powder form and L-Methionine. They are all 100% efficient to sustain broilers’ growth performance. This bio-equivalence has been proven in several in vivo trials in different conditions & performed in various geographical areas, field experience & trials worldwide and through modelization / statistical approach.
1. In vivo trials
Several trials were conducted throughout the years in various experimental research facilities in universities or in Adisseo in-house facilities: CERN (Center of Expertise and Research in Nutrition). We can name a few:
- Trials conducted at BARC (Thailand) or at Schothorst Feed Research (Netherlands) conclude that, when compared over a practical range of doses, both methionine sources sustain similar broiler growth performance.
- Various broilers’ trials conducted at CERN with different methionine sources tested (L-Methionine, DL-Methionine and OH-Methionine) demonstrating 100% efficacy of all sources in sustaining bird growth performance.
2. Field Trials
A field study conducted in partnership with a French poultry organization was held on an unprecedented scale in 2020.
The test was conducted on 10 months on more than one million broilers receiving feed with either liquid OH-Methionine or powder methionine (DL-Methionine) in blind conditions. Birds were reared in different facilities (50 farms in total).
The conclusion is that these methionine sources have the same efficacy to sustain broilers’ performance, as no significant difference was found on Body weight gain, Feed Conversion Ratio or other parameters between the broilers’ groups. Rhodimet® AT88 brings 880 g of methionine value in formula for 1 kg product.
3. Methodology approach
Statistical approach to compare the efficacy of methionine sources in broilers
This work conducted with UC Davis (USA) demonstrates the need of appropriate explanatory variables to estimate and compare the bio-efficacy of methionine sources. The best explanatory variable in this case is the methionine intake and in most of the cases, the best performing model is the exponential model.
Evaluating growth response of broiler chickens fed diets supplemented with synthetic DL-methionine or OH-methionine: a meta-analysis
Recently a new meta-analysis, result of the collaboration between UC Davis university (USA) and Adisseo, has been published in Poultry Science in April 2022. Compared to the existing meta-analysis, this new meta-analysis benefits from 4 main improvements:
- The application of more complex and powerful mathematical models
- The use of sulfur amino acids intake as explanatory variable, instead of Methionine dose (%)
- A focus on data below the breakpoint of digestible methionine content and digestible sulfur amino acids content
- Data sources from 1985 to 2019
Using powerful meta-analysis approach including the most recent studies, no significant difference in the weight gain was detected in response to DL-Methionine and OH-Methionine at or below the requirement.