Kieran Keane discusses recent findings from Teagasc’s feed analysis programme, highlighting notable variation in cereal crude protein levels ahead of the 2025 harvest.

As part of Teagasc’s feed and feedstuffs analysis programme for the pig sector we have been analysing cereals for well over a year now. As we approach the 2025 harvest now is a good time to reflect on results to date. We have seen a lot of variation particularly in crude protein levels of cereals. The table below shows the difference in crude protein in barley and wheat over the last 2 harvests.

Table 1: Crude protein results from wet chemistry analysis

The Average CP columns show the average crude protein values across all samples of that analysed ingredient from both the 2023 and 2024 harvest. The Highest 10% CP percentages are the averages of the highest 10% of results from each harvest and the Lowest 10% CP is the averages across the lowest 10% of results. As you can see there is considerable variation in crude protein and there has been a consistent decrease between the two harvests. This does beg the question: if the percentage of crude protein in wheat and barley is lower then what is taking its place.

Whilst the sum of the other nutrients does increase if crude protein, so far fat, fibre, ash and sugar don’t seem to follow a predictable pattern in relation to crude protein. However, dry matter and starch content do seem to have a closer relative link to crude protein levels. The tables below show the average dry matter and starch content of barley and wheat at 3 different levels of crude protein.

Table 2: Average dry matter and starch of barley and wheat at different crude protein bands.

As the level of crude protein increases so too does the average dry matter. This makes sense as the less moisture in the grain the more space for nutrients. Also, the lower the protein in the cereal the higher the starch. This is more pronounced in the barley analysed to date. As wheat and barley are bought mainly for their starch content this isn’t a bad outcome. So, the decrease in protein levels from the 2024 harvest were replaced in part by extra starch.

However, additional starch doesn’t necessarily mean that the energy of an ingredient is higher. Protein is also a contributor to the energy of a cereal. This means that a barley with 8% crude protein could potentially have the same energy as a barley with 11% crude protein when incorporated into a diet.  If we continue this example into a diet context where barley is 60% of the diet. It means that the dietary impact of using the 8%CP barley vs the 11%CP barley would be a decrease of 1.8% dietary crude protein with little or no energy decrease. As pigs will eat to energy we may be under or oversupplying protein to them.

We’ve seen firsthand in the lab how diet consistency can vary, even when using the same formulation. In one example, two finisher diets made to the same recipe just 10 days apart showed crude protein levels of 14.6% and 17.3%, respectively. The target crude protein was 16%, so while the average looks acceptable, the variation is significant. Lysine levels were measured at 1.04% and 1.16%, again the target was the average of these two, 1.1% total lysine. Synthetic lysine accounted for 42% of the total dietary lysine. This helped buffer the impact of the crude protein inclusion on lysine availability.

Interestingly, both diets had identical energy content, meaning pigs consumed similar amounts of feed each week, but received significantly more crude protein in the second batch. While pigs may still perform adequately on the 14.6% diet, the 17.3% batch represents a potential overspend. In fact, this difference could amount to an estimated cost of €3.50 per tonne, highlighting the importance of consistent diet mixing and regular feed testing.

Ultimately, ongoing analysis and adaptation will be key to maintaining feed quality and supporting animal performance in an evolving crop landscape.