Until recently, dietary fibres have often been regarded as an anti-nutrient, but that perception is changing. New technology developed by Cargill has allowed profound insights into the multifaceted roles of fibres, as well as identifying the types of enzymes that can optimise these functional roles to the benefit of animal gut health and performance.
In today’s Industry Perspectives piece, we talk in-depth to Ahmed Amerah, Technology Lead for Enzymes at Cargill, about this emerging research and its potential, as well as discussing what this might mean for ration formulation in future.
In this interview, we also discuss a recent research collaboration between Cargill and BASF. The work was undertaken externally by Professor Sung Woo Kim of the Department of Animal Science at North Carolina State University (NCSU), who talks about the research from his perspective in this interview.
[Feedinfo] Dietary fibres are usually thought to be anti-nutrients, but you have carried out recent research which shows that they may play a different role – can you tell us about this work?
[Dr. Ahmed Amerah] Indeed, it was traditionally believed that dietary fibre had anti-nutritional effects on poultry and swine, with concerns over its potential interference with nutrient absorption and digestion, leading to decreased animal performance.
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However, recent research has challenged this generalisation by demonstrating that the impact of fibre depends upon several factors, including its inclusion level in the diet, as well as its chemical and physical structure. Moreover, specific types of fibres have been shown to offer various gut health benefits to these animals. At Cargill, our dedication to researching dietary fibres spans over two decades, enabling us to understand and leverage their potential to enhance animal gut health and performance effectively. |
Dr. Ahmed Amerah |
[Feedinfo] Can you be specific about the functional role that fibres play?
[Dr. Ahmed Amerah] To clarify, when we refer to the ‘functional roles’ of fibres, we are describing the beneficial effects they promote within animals. These effects encompass a spectrum, from enhancing gut health by manipulating gut microbiota to improving nutrient digestibility through the stimulation of digestive tract development. Additionally, fibres can have secondary benefits such as improving litter quality, reducing ammonia emissions, and positively impacting animal welfare.
Beyond their chemical and physical structures, the functional roles of fibres are also dependent upon the species and subspecies to which they are fed. For instance, our research has illuminated that incorporating coarse particle-size fibre sources at low levels can stimulate gizzard development in broilers, leading to enhancements in gut health, nutrient digestibility, and litter quality. In broiler breeders, research showed that high inclusion of fibre-rich raw materials (wheat bran, palm kernel meal, sunflower seed meal) adversely affected nutrient digestibility. On the other hand, intermediate inclusion of such ingredients resulted in higher-than-expected digestibility coefficients compared to the average of the low and very high fibre rich diets. Considering evolving animal welfare standards, particularly with the prohibition of beak trimming, higher dietary fibre levels have been identified as a tool to mitigate issues such as feather pecking in laying hens.
Another area of research is enzymes targeting specific types of dietary fibres, such as arabinoxylan and β-glucan, which are commonly integrated into poultry and swine diets to enhance nutrient digestibility through various modes of action, including the modulation of gut microbiota.
While these insights are not novel, our approach to understanding the mechanisms of action of these fibres and technologies to modulate these fibres has evolved significantly. For example, through the utilisation of tools like Galleon™ Microbiome Intelligence developed by Cargill, we can delve deeper into the impact of fibre type and level on gut microbiota composition and the rate of microbiome maturation.
Furthermore, we can explore how specific enzymes influence shifts in gut microbiota, recognising that not all enzymes induce the same direction of shift. More recently, we've begun leveraging gene expression tools to gain a more comprehensive understanding of how fibres function at a molecular level. By combining insights from the Galleon™ platform with data from gene expression analyses, we can gain profound insights into the multifaceted roles of fibres, as well as identify the types of enzymes that can optimise these functional roles to the benefit of animal gut health and performance.
[Feedinfo] Do fibres have a different impact on poultry vs swine, and what does this mean for producers?
[Dr. Ahmed Amerah] The digestive systems of poultry and swine differ in their anatomical structures and functional processes. Poultry possess a gizzard, a muscular organ tasked with grinding ingested feed particles and thoroughly mixing them with digestive enzymes. However, conventional grinding practices employed by feed mills can reduce gizzard size and compromise overall gut function. Consequently, stimulating gizzard development through the inclusion of coarsely ground grains or coarse fibres becomes important to improve nutrient digestibility and promote gut health, particularly in pelleted diets commonly used in broiler production. However, in pelleted diets, it is difficult to maintain the larger particle size of the ground grains and then the coarse fibre inclusion becomes more relevant and gives a practical solution to stimulate the required gizzard function.
In swine, dietary fibre has been associated with reduced nutrient digestibility and increased demand for specific amino acids. However, the type and structure of fibre play a major role here, in addition to the age of the animal. Recent Cargill research conducted in the Netherlands revealed that the fibre fraction present in hydrothermal mechanical (HTM) processed soybean meal (SBM) possesses prebiotic properties, modulating microbiota composition through readily fermentable oligosaccharides. Moreover, HTM SBM exhibited double the non-starch polysaccharide (NSP) digestibility compared to conventional SBM, indicating more fermentation of the fibre fraction. In swine, a substantial portion of energy can derive from fermentation processes within the digestive tract, underscoring the importance of fibre’s role in energy utilisation.
It's crucial to recognise that the effects of fibre, influenced by its physical and chemical characteristics and inclusion levels, vary not only between poultry and swine but also within their respective subspecies. Understanding these complexities is critical for optimising nutritional strategies tailored to each species’ unique digestive physiology and dietary requirements.
[Feedinfo] Cargill and BASF have recently collaborated and worked with NCSU to look at the functional roles of NSP and its interaction with NSP enzymes. Professor Kim, can you talk about this in more depth from your perspective? The work also looked at how fibres and enzymes affected the gut microbiota and immunity – what did you find?
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[Professor Kim] This has been a great opportunity for me and NC State University to collaborate with BASF and Cargill. We have multiple research collaborations testing a hypothesis that exogenous NSP enzymes can provide opportunities to add functional values of NSP, helping the gut health of young pigs. We had extensive discussions to develop this hypothesis, experimental design, research protocols, and data analysis. This opportunity was a good example of industry-academia collaboration. |
Professor Sung Woo Kim |
One of the main questions to evaluate was whether exogenous NSP enzymes can provide opportunities to add functional values of NSP, helping the gut health of young pigs. Nutritionists know how to formulate nutritionally well-balanced diets for newly weaned pigs. However, it is practically hard to avoid antinutritional compounds in diets as antinutritional compounds are naturally included in major feedstuffs we typically use.
These antinutritional compounds are shown to alter mucosal microbiota, mucosal immunity, mucosal structure, digestibility, and growth of young pigs. Some soluble NSPs, including various types of arabinoxylans and galactomannans, are shown to possess antinutritional effects giving intestinal challenges, especially to young pigs and poultry.
Dietary supplementations of beta-xylanase and beta-mannanase have been shown to effectively reduce the molecular size of these soluble NSP to oligomers. These oligomers have been sources of shifting bacterial populations associated with the jejunal mucosa in a direction of reduced ammonia-producing bacteria and increased lactic acid producing bacteria. These changes directly and indirectly reduced inflammation and oxidative damage in the jejunal mucosa, resulting in improved nutrient utilisation in the small intestine with a positive growth response of nursery pigs.
It was also interesting to see that the presence of phytase enhanced the functional benefits of exogenous beta-xylanase and beta-mannanase. In these research works, we have been focused on investigating the changes in microbiota associated with the mucosa of the jejunum and related immune responses in the jejunum. This is related to the importance of mucosal microbiota and the small intestine specifically for young pigs (as compared to luminal microbiota and the large intestine for adult animals).
[Feedinfo] What does this work mean for anyone formulating diets, and can we expect to see more research which will develop this approach further?
[Dr. Ahmed Amerah] The practical implementation of new insights into the functional roles of fibres is of great importance. However, before applying this knowledge, a comprehensive understanding of the chemical composition and dietary fibre levels in feed is vital.
This knowledge forms the basis for anticipating the potential positive or negative impacts of these fibres. Adjusting fibre levels and types to optimise their functional roles and potentially formulating diets around such insights may become standard practice. For instance, at Cargill, we've pioneered a distinctive approach to characterising various carbohydrate fractions, including fibres, in ingredients.
This knowledge resulted in the creation of two unique nutrients tailored for pigs throughout their lifecycle, namely, structural, and fermentable carbohydrates. This classification allows us to quantify the biological functions of these fractions across different ingredients, translating into precise nutrient recommendations for feed formulation. These recommendations aim to achieve desired performance, sustainability, and economic goals while promoting gut health and performance. Maintaining a balance between these nutrients throughout a pig's lifecycle is essential. Our research indicated that imbalances can significantly impact animal performance adversely.
An inevitable question arises: How can we manipulate the fibre fraction to achieve this balance or mitigate the negative effects of certain fibre types? One strategy involves the hydrothermal (HTM) treatment of selected ingredients, offering a means to modify fibre properties. Additionally, enzyme supplementation becomes indispensable for mitigating the adverse effects of specific fibres, such as arabinoxylan, ß-glucan or mannan, while facilitating the creation of desired fermentable fibre types that function as prebiotics. At Cargill, we synergise both hydrothermal (HTM) treatment and enzyme supplementation technologies to optimise the gut health benefits of fibres, thereby maximizing animal performance.
Published in association with Cargill