An increasing number of countries are banning or limiting the use of antibiotics. This stimulates the believe that supporting beneficial microflora will boost the animal’s innate immune system in more than one way. Eubiotics play an important role because they not only act locally, but also have an indirect positive systemic effect.
|The application of benzoic acid in piglet feed has been shown to suppress pathogens like Escherichia coli (pictured) and Salmonella. Photo courtesy CDC/Janice Haney Carr
By Jorge Cervantes López, regional product manager – Eubiotics, DSM Nutritional Products
Just a few decades ago, vitamins were considered ‘additives’, meaning they were considered useful but not essential. Today, we could not even consider a diet being complete, or in some countries even legal, without the addition of vitamins, almost for all farm species. The same scenario is being repeated today in the case of eubiotics, products that instead of working only against harmful bacteria (such in the case of antibiotics) work towards improving overall gut health and animal performance. The ban of antibiotics as growth promoters in several countries worldwide has caused many problems, but created new challenges and opportunities. Today, based on extensive research and commercial experience, the search for antibiotic replacements, the eubiotics, have opened new horizons in the management of gastrointestinal health, with or without the use of old-fashioned antibiotics. What was considered up to now as ‘additives’ is now considered, in most piglet formulations worldwide, an essential part of quality feed.
The best example is the case of probiotics. Beneficial bacteria are fed to animals to help in the establishment of a healthy microflora to compete against pathogenic bacteria. Today, of course, using probiotics is part of an integral approach in replacing antibiotics. But, even where antibiotics are (still) allowed, adding the right probiotic product in the feed continuously even during antibiotic ‘pulses’ is considered beneficial in establishing a gut microflora that will be even healthier than before; thus minimising the need for further or stronger antibiotic ‘pulses’ down the productive cycle. Certainly, there is nothing better than natural immunity, and such a benefit can be obtained by a self-sustained and healthy gut system.
The application of benzoic acid
Finally, it has become common knowledge that a healthy gut means a healthy microbiota, reflected by a balanced diversity among beneficial micro-organisms at the exclusion of pathogenic ones. Antibiotics work towards eliminating certain pathogenic bacteria, but do not influence the rest of the microflora. On the other hand, a well-designed complement of eubiotics not only offers the same bacteriostatic and bactericidal effects, but it also offers the extra benefit of helping in establishing and maintaining a healthy gastrointestinal flora. This second part can be of use even in the case where antibiotics are still part of an overall farm health programme.
For example, the application of benzoic acid in piglet feed has been shown to suppress pathogens like Escherichia coli and Salmonella. In fact, benzoic acid has been shown to be the most efficacious organic acid, in that a smaller dosage is required to suppress a larger population of these pathogenic microorganisms. However, it is now known that organic acids must first cross the bacterial cell wall of pathogens in order to enter in the cytosol where they will exert their disrupting effect causing cellular death. On the other hand, it has been realised that certain plant extracts, such as eugenol and thymol, can substantially increase the permeability of the bacterial outer membrane, thus making the work of benzoic acid even easier as it can attack bacteria with a greater number of molecules. And, when a probiotic preparation is added to this blend, then there is maximal efficacy as the pathogenic bacteria eliminated are replaced by beneficial strains.
Benefits of eubiotics
In essence, gastrointestinal health is not a linear process, but a dynamic one where many factors are interlaced; that even when antibiotics are used, there is still room for improvement in terms of gastrointestinal health. And, so far, we have discussed only ‘passive’ gastrointestinal health, in that, the major factor concerned has been the balance between the ‘good’ and the ‘bad’. There is also an ‘active’ part that is being played by the beneficial microflora, and that is the enhancement of host immunity. The majority of scientific evidence goes towards the direction of supporting the hypothesis of beneficial microflora boosting the animal’s innate immune system, in more than one ways. Thus, eubiotics act not only locally, but have an indirect positive systemic effect.
Other benefits we have come to recognise in eubiotics, again as part of the continuous search for antibiotic replacements, is that of digestive aid. For example, curcumin and piperine are known to stimulate the secretion of digestive enzymes, therefore enhancing nutrient digestibility. This not only improves animal performance (direct effect), but it also deprives pathogenic bacteria in the lower gut segment of essential nutrients that they would otherwise use to grow and proliferate (indirect effect). Of course, the stomach acidifying potential of certain organic acids is also well known: reduced stomach pH increases protein digestibility and this translates to improved growth and feed efficiency or in reduced feed cost (if the effect is taken into account during feed formulation). Thus, it is seen that eubiotics can not only replace antibiotics, but in addition, they offer further benefits, quite often even in the presence of antibiotics.
Currently, the European Union, South Korea, and New Zealand prohibit the use of antibiotics in feed for growth promotion, whereas other countries allow the use of some antibiotics, even though they are constantly reviewing their policies for approved uses. In many other countries, antibiotic use surveillance and resistance data collection systems have been developed in order to monitor and safeguard against resistant strains that could potentially threaten public health. Even in countries where antibiotic use is not restricted, there is discussion in production circles about voluntary use of antibiotic replacements, especially when end products are destined for exportation to countries that ban or control use of antibiotics. Final remarks: There is a growing globalised concern on the prevalence of resistant bacteria to antibiotics. There is no denying that the post-antibiotic era is already here and even if not yet in all countries, it does not hurt to be prepared, if only to be able to export meat and eggs in a global economy. There is considerable experience gained through much trial and error in countries which they first went the path of complete ban on antibiotics, and the process has revealed not only suitable replacements, but also new unexplored frontiers that take animal health to new levels.
As with any additive, there is always a period of ‘testing’, but those that actually offer substantial and tangible benefits quickly become essential. As long as animals are raised under commercial conditions where their health is far from ideal, there is always room for new technologies in improving their health and welfare, and in the process even protecting our own health and welfare, in the long run. Because eubiosis is a virtue that we owe first to ourselves.