Attaining good gut performance has become increasingly important to livestock producers. Phytogenic feed additives (PFAs) can support good gut performance and improve feed efficiency in broilers through several ways. Battling against anti-nutritional factors is important, as is improving feed digestibility, increasing the gut’s absorption of nutrients and reducing inflammation. Plant-derived feed additives constitute a powerful tool in this regard.
Phytogenics – to get the most out of feed
The incredible biodiversity of the plant kingdom provides a large variety of different herbs and spices with an enormous number of active substances exerting different effects in the organism, ranging from stimulating endogenous enzyme secretion over influencing gut microbiota to enhancing gut protection. Their mode of action depends on the chemical structure of the active substances or constituents. Spices, herbs, essential oils or extracts exert different effects. For example, phenols such as thymol, carvacrol and eugenol (often derived from thyme, oregano and clove) and their methyl ethers have a very strong antiseptic and antimicrobial effect. Species of the families of Apiaceae such as caraway and fennel and Lamiaceae (e.g. rosemary and peppermint) have strong antioxidative properties. Other plant compounds support better digestibility by boosting digestive secretions such as bile, mucus and saliva as well as enhancing enzyme activity. Constant and reliable results in animals, however, can only be achieved with a well-defined formulation of a phytogenic blend, including standardized raw materials and effective quality control.
Phytogenics’ effect on nutrient digestibility
Gut morphology, gut protection and digestibility are interrelated and share the same target: optimizing feed consumption, minimizing losses due to poor digestion or intestinal disorders and maximizing performance. Recent scientific research at the Free University of Berlin found an innovative phytogenic feed additive* to be effective in improving nutrient digestibility and performance.
In two experiments improvements were seen in the apparent ileal digestibility of dry matter, crude ash, crude fat and calcium. The phytogenic feed additive delivered statistically significant improvements in phosphorus apparent ileal absorption as well as protein and total amino acid apparent ileal digestibility (p<0.05; Figure 1). A deeper look into single amino acid digestibility revealed statistically significant results (Figure 2). Of particular interest are differences in the first limiting amino acids in broilers. Improved digestibility does not only affect poor digestion and intestinal disorder thereof, but also are of interest due to increased performance and a positive economic result.
Digestibility: the prerequisite for performance
In another experiment, performance parameters were evaluated at the Free University of Berlin. In terms of performance parameters, Hafeez et al. 2015 showed that live weight was improved by 2.5% and feed efficiency was improved 1.9% when applying the phytogenic feed additive for 42 days (Table 1). Increases in performance parameters are even more remarkable when taking into consideration that control birds outperformed the Cobb 500 standards at 42 days of age for live weight, feed intake and feed efficiency (Table 1). The positive trial results produced an economic benefit with a net return on investment of 3.4:1.
Gut morphology: an influencer of digestibility
Improvements in digestibility of nutrients can be attributed to various factors in the gastrointestinal tract. Contributing elements are enhanced endogenous secretion and improved gut morphology. The latter is determined by the depth and length of crypt and villi in the gut. An experiment carried out at a research facility in France confirmed positive effects of the phytogenic feed additive on intestinal enzyme activity. In this study enzymes involved in sucrose, disaccharide maltose and amino acid breakdown showed increased activity (+26.2 to 27.5%) in broilers compared to control birds. Higher enzyme activity correlates positively with a greater digestibility of nutrients. Furthermore, a study conducted at Purdue University demonstrated the additive’s positive effects on birds’ intestinal morphology. Here, Reisinger et al. (2011) concluded an increase of villi length by 11.9% in challenged birds receiving the phytogenic feed additive compared to challenged control birds. Increased villi length is positively reflected in more differentiated cells and an increased capacity for nutrient absorption.
Increased gut protection
Other decisive criteria for gut health are inflammation and antioxidant status of the animal. Inflammation leads to decreased gut protection in the intestinal tract resulting from infections or feed-dependent changes. Inflammation is a costly process since it often involves significantly reduced feed intake and spends energy (the body’s natural response to counter inflammatory processes). These processes together with a decreased antioxidant status are related to lower performance (growth rates, laying performance, etc.) and associated with higher morbidity and mortality. The anti-inflammatory effects of phytogenic compounds were examined in a number of studies. The direct anti-inflammatory activity of the phytogenic feed additive was shown in a test model with inflammation-induced intestinal cells at the Justus-Liebig-University Giessen, Germany. Results demonstrated that the selected phytogenic additive decreased the inflammatory response and supported the protection of intestinal tissue by exerting antioxidant activities.
Solutions to improve efficiency in poultry production rely on good gut performance in the animal. Impaired feed conversion resulting from poor digestion and intestinal imbalances leads to a cascade of problems resulting in decreased performance. The significant influence of a precisely formulated phytogenic feed additive on gut performance via increased enzyme secretion, improved gut protection and positively influenced gut morphology contributes to an improvement in digestibility. Digestibility improvement with the selected phytogenic feed additive was in this instance confirmed in a cooperation with the Free University of Berlin. Scientific findings of enhanced digestibility show the direct correlation of improved feed efficiency and performance in animals. Both benefits are linked to greater economic success for producers.
*Digestarom® (Biomin Holding GmbH, Austria). References available upon request.
This article originally appeared in All About Feed.