Context
In relation with its physiology and its high growth potential, the double-muscled Belgian Blue bull (dmBBB) has specific needs in amino acids compared to the other breeds used for meat production. A typical diet, based on maize silage and soybean meal, doesn't supply all the amino acids in sufficient amounts to the animal, limiting by this way the growth and the feed protein valorisation. In these practical conditions, the supply of a feed additive specifically enriched in the main limiting amino acids (His, Met, Arg, Lil, Val) permitted to increase the average daily gain of the animals by 250 g/d (Fiche n°53). Unfortunately, the cost of this additive didn't make it competitive on the economic plan. Therefore, we looked for protein sources presenting a high quality in their amino acid profile in order to satisfy the needs of the dmBBB. The potato protein concentrate (CPPT) has been chosen because it is produced in Europe, that its amino acid profile is better than that of soybean meal for 7 of the 9 essential amino acids and finally because its proteins are little degradable in the rumen. It is a by-product of the starch industry.Objectives
The objectives of the trial are: 1) to compare the nutritional interest of the CPPT and soybean meal on basis of in vivo measurements 2) to evaluate the capacity of the CPPT to improve the profile of digestible amino acids supplied by a typical diet at practical incorporation ratesResults obtained
CPPT and/or soybean meal were incorporated in iso-N and iso-VEVI diets in order to supply 30% of the proteins ingested by the animals. At this incorporation rate, no meaningful difference has been observed in the rumen fermentation parameters, neither in the digestion nor in the digestible supplies of the main nutrients (DM, OM and N). The source of proteins incorporated in the rations didn't influence the nitrogen retention of the animals, and didn't have any effect therefore on the growth performances. On basis of in vivo observations, the protein degradability of CPPT and of soybean meal was determined respectively at 0.43 and 0.60; confirming the values mentioned in the literature. The contributions and the digestible amino acids profile in the small intestine didn't differ between the CPPT or soybean meal based diets. The results of the test show the difficulty to modify the digestible amino acids profile by the manipulation of the feedstuffs incorporated in the diet. The nutritional interest of the CPPT appears limited compared to soybean meal for the dmBBB feeding.
Contribution
Project coordinatorPartners
University of Gembloux, Industrial Biological Chemistry Unit (Prof. B. Wathelet)
CRA-W, (JM Romnée)
University of Gembloux, Animal Production Unit (G. Jean, C. Boudry)
CRAW off coordinator
Dr Eric Froidmont
CRA-W
Rue de Liroux, 8
B-5030 Gembloux
Tél. : +32 (0)81 62 67 74
Fax : +32 (0)81 62 58 68
Email : froidmont@cra.wallonie.be
Funding
- CRA-W - Walloon Agricultural Research Centre
