Finding the right amount of methionine required in animal feed

The current raw material cost pressure is immense in all areas of animal production

In order to minimise such cost impacts, everyone is trying to remove any unnecessary costs, while maintaining animal productivity, health and welfare.

One area that should be reviewed is safety margins. This is how nutritionists try and cope with the variable nutritional content of raw materials, basically by either formulating to produce formulae with levels of critical nutrients slightly above those actually required by livestock; or by slightly underestimating the supply from the raw materials.

Either approach requires very good understanding of raw material quality and its inherent variability. It also requires complete confidence in the supply of nutrients from pure materials such as methionine sources. When safety margins are wide, any incorrect assumption on nutrient supply can be covered by slight oversupply from all raw materials. If safety margins are reduced or removed completely, this deficiency will be exposed, leading to reduced animal performance.

A good example is methionine – the first limiting amino acid in poultry feeds. It can often be the primary limitation on performance, after energy. A mistaken value applied to one of the two main sources of methionine can have a profound impact. Research has consistently shown that the methionine precursor MHA-FA has an efficacy of only 65% compared to the standard DL-Methionine. However, many people are persuaded to use a much higher value, often around 80%. This means that in a typical broiler feed diet containing 3.5 kg MHA-FA, there is a potential deficit of 0.05% digestible methionine. When safety margins are removed or reduced, this gap in supply will potentially lead to reduced growth, increased FCR, and an increased risk of intestinal problems due to other underutilised amino acids acting as a growth medium for gut flora.

Click here to see your benefits through the MetAMINO calculator.