Economics of Low Protein Broiler Diets: A Formulation Exercise
Published:February 25, 2021
Summary
I. INTRODUCTION Papers have been presented at the past two APSS meetings on the subject of low protein diets (Kidd and Choct, 2017; Hilliar and Swick, 2018; Lambert and Corrent, 2018). Few, if any, have taken note of the economics of such diets. This paper is an examination of the costs of low protein diets. A brief history of amino acids is worth reviewing. Each time a limiting amino acid be...
Good day,
100% correct. We have tried lower protein diets in Canada as well, but almost always, higher protein diets are more economical and the performance is better as well. And I've tried supplementing with synthetic VAI as well.
What wasn't mention in the article was the protein level in the wheat used, as that makes a huge difference in the ability to lower protein levels and/or performance. The higher protein wheat (150 g/kg) along with lower protein in the diets will make for worse results then say using a wheat that has 105 g/kg.
Thank-you for sharing your work.
George Entz,
Dear all, enzymes are specific of substrates, I strongly recommend to check the energy and amino acid value improved by phytases or NSP xilanases, take care, the effect is secundary, and because of that inconsistent, dependent, if you have low phosphorus level or NSP carbohidrates in your diet, and you have the secundary effect because of Phosphorus defficiency, amino acid digestibility values are decreased, if you are phosphorus or phytase and recover phosphorus, what you really do is to recover amino acid digestibility values, if you give a matrix on amino acids and energy when you have secundary effects what you really are doing is over estimating the value of enzimes, and I have seen several mistakes and issues on the field due to over estimation of enzymes or other additives, blaiming secundary effects
Carlos Martínez Amezcua,
Sorry there is a mistake, in my comment>
Phosphorus defficient, amino acid digestibilities values are decreased, if you add phosphorus or phytase, what you are really doing, is recovering AA digestibility, just think, what is the right sentence
1) Phosphorus Defficient diet AA dig 70/80 if add phosphorus or phytase recovers to 88/90!! or
2) PHosphorus defficient diet AA dig 88/90 % and if add phosphorus or phytase you move it to 100%??????????????,
Take care!!! second answer is what you are doing if you give matrices because secundary effects
Carlos Martínez Amezcua Hi Carlos, Great point you are making! If we reduce the crude protein and use more crystalline amino acids to satisfy their requirement soybean meal inclusion is decreased. There will likely be less benefit of phytase as there is less substrate (phytin) for the phytase to degrade. I don't have the full answer but I agree that the phytase matrix values will likely be affected. Bob Swick
Dear Bob,
Thanks for sharing this work.
Did you apply in formulations all parameters of matrix of enzymes: minerals plus energy plus AAs? And when combining phytase with NSPase, using 80% of each matrix for AME and AAs?
Dimcho Djouvinov
Hi Dimcho,
I use full matrix values for phytase being what the manufacturer recommended for energy, Ca, P, Na, amino acids for the dosage used. I do not use matrix values for xylanase. If the wheat seems to be low energy based on Evonik NIRS NRG scanning, I add 60 to100 kcal/kg to the AMEn when using xylanase. I believe the xylanase does a good job at raising the AMEn of low energy wheat and reducing the variability.
Of course what ever one does can be criticised but that is what I do.
Best regards,
Bob Swick
Robert Swick What's your opinion on using phytase+xylanase/NSPase and considering their matrix as 1+1=1 (like we do at commercial level to avoid inconsistency of ingredients) OR 1+1=2 (seems logical on mathematical grounds) OR 1+1=3 (could be logical as more enzymes release entrapped nutrients by breaking complex NSP+phytate structure)?
Juarez Donzele I tend to agree. I think there is a lot of focus on reduced protein without regard for economics and performance. And in the real world, we have challenges with Eimeria and Clostridium not to mention viruses and parasites. When there are GIT challenges, having less undigested protein reach the hindgut is advantageous as there will be less ammonia produced. Ammonia increases pH and favours the growth of Clostridia. This means it is better to formulate feed with protein that is highly digestible as opposed to poorly digested. A combination of high quality grain, soybean meal and lysine with methionine and threonine is recommended. Bob Swick
One must have high quality ingredients for performance. Also L Value, L Arginine plus glycine to provide a nitrogen pool when using low crude protein diets
Cheap will not work
John Wills, PhDHi John!
Yes I totally agree that cheap will not work! Nothing better than intact protein from soybean meal (when sustainably produced) balanced with minor amounts of added amino acids to meet the ideal digestible amino acids requirements. All the best!
Bob
Robert Swick
Although their considerations are consistent, it must be considered, that in addition to our previous considerations, that the health challenge, mentioned above, constitutes one of the factors, which can compromise the performance of the birds, when the crude protein is reduced. This is due to the fact that the health challenge increases the demand for amino acids considered as non-essential, including glutamine, glutamate and glycine, whose concentrations are reduced. Even due to this fact these amino acids are considered conditionally essential.
The prices are a moving target. But yes that paper is AUD not Euros. We can say that as time goes by, the purified AA sources will likely get cheaper as demand picks up and economy of scale is realised. The next thing to be considered will be sustainability. On first thought, most will think purified sources will be more sustainable than SBM. However one needs to consider the input materials to produce purified AA sources including water, starch, sugar, nitrogen and electricity for maintaining fermentation temperature and drying the final product. Methionine is truly synthetic being made from petroleum derived chemicals methyl mercaptan, acrolein and hydrogen cyanide (and petroleum is not very sustainable). Soybeans are grown on farms using varying degrees of sustainable practices. But they do employ rural people and put more nitrogen into the soil than they take away. The amino acids produced by soybeans use nitrogen fixed from the air. When produced in situations where they do not impact important natural habitats they are truly a highly sustainable miracle crop.
Robert Swick . Excellent comment on sustainability, however do not discount the sustainability of the chemicals used to produce the amino acids and vitamins. Many times the production of these nutrients using chemicals is an integrated operation and they used chemicals (by products) from the production of other products. Many times cyanide and HCl acid are in surplus from other reactions. To get a true value of sustainability, one must calculate the entire production processes of producing several products.
David Wicker Ph. D.Hi David, Thanks for the comments and great to hear from you! Yes, the sustainability aspects need to be worked out for sure. Getting an economic value is relatively easy compared to a sustainability value. Sustainability needs to consider things like fossil fuel consumption, climate change, eutrophication, acidification, smog formation, land use, employment and probably some others we haven't thought of yet. And then we need to distill them down into a simple index so we can use it to formulate feed. Perhaps such an index can be used as another "nutrient" in the ingredient matrix. The weighting of the components of sustainability will require some agreement between people. Anyway just some further thoughts..... Best regards, Bob
