Feed Polysaccharides: Nutritional Roles and Effect of Enzymes
Published:January 31, 2011
Summary
INTRODUCTION Cereal grains and vegetable protein sources contain between 10-75% of non-starch polysaccharides (NSP). NSP in cereals form part of the cell wall structure and in vegetable proteins, such as legumes, may also play a role as an energy storage material. As far as monogastric animal nutrition is concerned, NSP as the major part of fibre (fibre is the sum of NSP and lignin) are regard...
Thank you very much for your excellent article on the use of enzymes in poultry feeds containing cereals. Algeria is a major producer of barley, poultry feed manufacturers have substituted some corn imported with barley. Replacement rates corn are 25[percent] in laying hens and 35[percent] in the broiler diets. We used an enzyme complex containing several enzymes. Performance of production (laying rate [percent], egg quality, body weight, feed intake, feed conversion….) were unchanged compared with birds receiving 100[percent] corn
Very interesting and informative article for the nutritionists. There is great influx of NSP enzymes in the market by various companies all over the world. Everyone pushing its product to use for some extra energy or to save some cost or both. Author has discussed many aspects of this issue and I am sure that nutritionist could get some very useful information to decide to include enzyme in their diets or not through this article.
Well Done.
Re Nadir's comments, I would like to make two points; firstly, the enzyme. There are many types of enzymes all purporting to enhance nutrient digestibility. However, there is tremendous variation in their efficacy. For example, a single fermentation using A. niger can produce 11 different families of xylanase with a wide range of efficacy and activities in terms of substrate affinity and other characteristics, such as pH sensitivity and thermostability. So until we have a method to predict enzyme response accurately, it is difficult to know whether an enzyme has done what is supposed to; secondly, the substrate. In this case, barley was used to substitute corn. The key substrate is the beta-glucan, which is affected by storage, variety, and geographical location where it is grown. Thus, it is possible that the barley used in the experiment was a low viscosity barley which does not respond to enzymes as well as a high viscosity (high beta-glucan) barley.
Sometimes you see a literature of a enzyme product, even by an internationally reputed company, you find a long list of enzymes in their product and when you used the product according to their instructions, you end up in huge losses. The companies tend to provide incomplete information in their product rather they only provide information that support the selling of product. They shamelessly sell the product to a client who trusted them and when the product never works, they have many excuses and try to sell another product. But most of the times they never return to the customer.
I believe that use of enzyme to improve performance in not a simple task, a nutritionist most study in detail of all the ingredients of the diet and most use some independent source of literature to calculate different options.
When feed is formulated between 3100 to 3300 Kcal and product ask to adjust 150 Kcal, which is less than 5% of ME and even with that high energy diet CV is more than 5%, you can never access that the enzyme product worked on not. The real challenge would be when you formulate a low density diet with 2750 Kcal and then use the product to get the results. In this kind of diet, real potential of enzyme could be tested.
Very good article enlightening the soluble & insoluble NSP of all carbohydrate sources of the most dietary energy & fiber found in major feed ingredients used for monogastric diets.
Use of cocktail enzymes will help for the utilization of both soluble & insoluble NSP for additional energy source.
Nutritionists will definitely take note of this article.
Thanks for comprehensive review on Polysaccharides degrading enzymes. I think in the Maize Soy diets particularly in Broilers enzyme supplementation give inconsistent results. Secondly enzyme products are so variable that their cocktail of enzymes vary considerably. As the age grows there is less use of enzymes. If we increase the dose diarrhoea occurs. If we supplement antibiotics with enzymes the performance dips. Can individual enzyme products eg. pectinases or cellulases can come in the marlet? Only phytase in layers and NSP degrading enzymes in Wheat, Oat based diets are successful. At present price of wheat is more than Maize. Thanks.
Congratulation for a very informative discussion on enzymes. I had been working and also tried different enzymes preparation. And it is true that different companies claimed differently. I agreed on what you have discussed that variation on the nature of which the enzymes were extracted. And various degree of fermentation could affect the potency and stability of the enzymes. To those interested in evaluating enzymes just remember the lock and key principle. And also the ration of the substrate vs the specific enzymes you are evaluating. Its does not mean when the manufacturer indicates a enzyme is there with out the specific amount it is sufficient enough to act on the said substrate. All enzymes might have side activities. Enzymes indeed minimize the variability in nutrients of raw materials.
I also agreed with Dr. Ramzee that enzymes should be tested on the extreme or at lower energy level of their claim. Enzymes also is not linear. Find the right combination of enzymes depending on the feed ingredient you are handling.
Dear Readers,
I also validate that the ME sensitivity is greater for the lower ME diets and studies should be done for low caloric density diets such that the true potential of the Carbohydrases/ NSPases could be established.
Also there should be some correlation established between different exogenous enzymes sources and there assay methods with respect to there application in the feed.
Moreover, Some commercial products have irrelevant enzyme in their cocktail products,some of which are already endogenously present in the monogastrics in abundance.
Overall-this article is very informative.
Regards
The key is to understand the nature of the substrates present in the ingredients used to formulate the feed. For soluble NSP (fibre) like beta-glucans and arabinoxylans, xylanase and beta-glucanase are highly effective in depolymerising these NSP into smaller polymers (with some limited amounts of monomers released). This action acts like removing the snags from a river, leading to amelioration of the anti-nutritive effects of NSP on nutrient digestion and absorption, restoring normal gut function, including digestion and absorption of nutrients.
For insoluble NSP, such as cellulose, straight-chain mannans, lignified or methylated xylans etc., the action of carbohydrases is highly complex. Some enzymes targeting these polymers will be able to cleave the molecules occasionally, leading to opening up cell walls and giving endogenous enzymes access to entrapped nutrients. But it is extremely difficult to use enzymes to release enough monomers from insoluble NSP to have a noticeable effect on ME in monogastric animals.
Thus, predicting enzyme response in monogastric animal diets will require an accurate understanding of the substrates present in the ingredients, the activities (both in-feed and in situ) of the enzymes used, and other factors such as the endogenous enzymes present and the efficacy of products released by the exogenous enzymes in contributing towards energy metabolism and protein accretion.
Hello Dr. Choct, if you ever read this comment since is more than 2 years you answered to some other people. I am a great admirer of your work and I am so interested - I work with Danisco Animal Nutrition in West Europe - . I would like to know in the light of your last comment (April 2011!) what kind of enzyme activity would then be needed in a completley wheat based diet in poultry; would a single xylanase be enough (so it helps with both sNSP and insNSP)?. Many many thanks, hope one day you come over to Spain and we could meet (easier this than me flying to Australia). Cheers from Madrid.
Dear Rafael, I am sorry this has taken such a long time as I have overlooked your comments. It is a very good question because wheat contains not only arabinoxylans but also an appreciable amount of beta-glucans. So in theory, products with xylanase and beta-glucanase activities would do a better job than single activity products. However, we have seen single xylanase products having equally good effects on the performance of birds fed wheat-based diets. The problem is that wheat quality varies tremendously and it is impossible to dissect the effects of various factors including enzymes in a complex diet fed to animals that, in turn, are affected by other factors such as the environment, management and disease. Re insNSP vs sNSP, we published a paper in British Journal of Nutrition in 2004, which compared three different xylanases that had different substrate affinities.
Many thanks Mingan. Great answer and we had the chance of meeting each other very recently, during EPC at Stavanger. Keep the sharing and finding great discoveries for the rest. Thanks.
Good day, nice article indeed. in our market we have a lot of wheat bran and corn bran. is there any experience on the level of inclusion of these ingredients for broilers and layers with use of enzymes?
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Reply
Tahir Mahmood
16 de octubre de 2016
Dear Mingan, I have gone through many of your research articles and these papers always give a deep insight about the role of NSPase more often in wheat-based poultry diets. In countries like Pakistan where wheat being the staple food for the general masses, government exercises control over use of wheat in poultry diets. Therefore, the feed industry usually uses maize-soya diets. Most of the nutritionists in Pakistan believe that there is little room for improvement for NSPase in maize-based diets. Some commercial companies have started marketing NSPase which contain debranching enzymes as well. You along with your team being the real experts in NSPase domain are in a better position to explain the real use of NSPase with debraching enzymes in maize-based diets. I would like to know your thoughts about this issue.
Regards,
Tahir
HI SIR, I WANT TO KNOW HOW MUCH CRUDE PROTEIN WE CAN TAKE FROM SUPPLEMENTAL AMINO ACIDS OF THE TOTAL CRUDE PROTEIN OF THE DIET. E.G., IF THE CP OF DIET IS 22%, THEN WHAT PERCENTAGE OF IT MAXIMUM SHOULD COME FROM CRYSTALLINE AMINO ACIDS. best regards
