Fattening pigs

Alleviate the strain on nutrient balance with feed concepts

AGRAVIS Raiffeisen AG re-conceived OlymPig pig fattening feed and adjusted it to the current conditions. The new fattening feed now corresponds to all the criteria of the feed with much less N and P.

Bernhard Walgern

The aim is to feed the pigs as far as possible "right to the point", because overconsumption leads to unnecessary excretion and thus more manure. The nutrient balance is sustainably improved through the developed feeding concept and contributes to safeguarding the future of pig fattening. AGRAVIS expert Bernhard Walgern explains the background and details of the new feeding concept.

What was the reason for the new concept?

Walgern: The new German Fertiliser Ordinance was impending and it further limits the fertilisation of manure. Instead of 20 kilograms of phosphorus (P2O5) surplus per hectare, only 10 kilograms are allowed. The reduction of the creditable N-losses is also an issue. Just like the consideration of nitrogen from the biogas fermentation residues. All of this combined leads to larger space requirements. We would like to pass on our know-how on the reduction of nutrient excretion through our feeding concept to pig farmers.

What changes are there in the feed itself?

Walgern: For an exact feed supply without overconsumption, the feed is designed on the basis of digestible nutrients. On the one hand, we combine "ideal protein" with an energy assessment according to net energy. And on the other, we calculate the feed based on digestible phosphorus. Pressure is taken off the animals' metabolism and N and P excretions are reduced further. All new developments have no impact on the performance of the animals – on the contrary. They go hand-in-hand with improved animal health. And healthy animals are high-output animals.

Evaluating energy from feed

What do you understand by ideal protein?

Walgern: In order to ensure fattening and slaughtering performance, nine praecaecal digestible (pcv) amino acids are now taken into account. Thus, even with a lower content of raw protein in the feed, all amino acids are sufficiently contained as a building block for body growth. Moreover, the reduction of raw protein in the feed also leads to lower heat loss in the metabolism. The animal therefore has more energy available for growth. In order to prevent this increase in energy turning into fat, we are now assessing the feed on the basis of net energy.

What is the difference between metabolisable energy (ME) and net energy (NE)?

Walgern: Contrary to the previous assessment according to metabolisable energy, in the net energy system, heat loss in the metabolism is taken into account in addition to energy loss from faeces, urine and methane. The lower the raw protein content in the feed, the lower the heat loss. The net energy system enables a more precise energy supply for the pigs, especially in the case of raw protein-reduced feed.

How is a further reduction of phosphorus content possible?

Walgern: The pig's phosphorus need is based on digestible phosphorus. The digestibility of the phosphorus contained in the vegetable raw materials is improved by correspondingly adding the enzyme phytase. Thus it is possible to reduce the total proportion of phosphorus in the feed whilst still maintaining the content of digestible phosphorus.