By Richard Turner, vet and director, St David’s Poultry Team
Over the last five years, the poultry industry, vets and nutritionists working together have achieved a great success in reducing antibiotic usage and it shows with the present level in broiler use being very low. Yet, where do we go next and equally, how do we make further reductions?
To be clear, it is my opinion that total removal of antibiotics from poultry production, in any form, would create animal welfare issues, raised mortality and poor production. It is a dream that making the animal production systems more extensive will achieve a zero usage level, particularly as we are still faced with high mortality and disease in free range and organic systems. The only way to have no antibiotic usage is to have no animal farming, which is possibly the ideal of some, but not of the majority.
It must not be forgotten that antibiotic resistance existed before any modern systems of animal production were developed, and even before antibiotics were commercially produced. The major area of stored antibiotic resistance is the soil. Within the soil structure and the surrounding plant roots, there is a war going on between bacteria trying to invade the plant root tissue, the plant producing various chemicals such as essential oils and its co-habiting fungal populations producing anti-bacterial chemicals, of which the most well-known would be from Penicillium moulds. In ancient caves scientists recently found bacterial populations with extensive antibiotic resistance. Human and animal use of antibiotics has no doubt increased the pressure on resistance and it will be very difficult to turn the clock back now resistance is so widespread in the environment. Yet, we have to try, as a world with no antibiotics is a serious worry.
Looking specifically at broiler antibiotic reduction, the basic tools and protocols are now well understood and the investments farmers have made in new buildings and advanced ventilation systems has made the implementation easier. The issue now is how we keep these low levels in a commercial world where there is no better financial return to the farmer in not using antibiotics, but an increased risk to his birds’ health and possible poorer efficiency.
The retail sector expects low controlled usage of antibiotics, the informed consumer wants this, but they both need to pay more for the product. Antibiotics and other forms of modern medicine are still the most effective way of treating bacterial infections. They are relatively cheap, easy to apply and well tested and regulated. Moving to alternative solutions the challenge is greater. There is no one product, or system, that will replace conventional medicines in the control of disease, but a range of husbandry increased costs, multiple alternative product interventions and the need, most importantly, for better monitoring and diagnosis of the early stages of illness. Even with our own health we often leave treatment later than we should because a course of antibiotics will cure even when the infection is established. In a non-antibiotic world this option will not exist.
Moving to a sustainable low level of antibiotic usage will require a detailed overall plan for the whole pyramid of production. At the high levels of pedigree stock, the innate immunity passed to offspring will need to be one of the most important selection factors, and tests and monitoring systems will need to be developed to ensure breeding programmes are achieving progress. There is no doubt that in the past some broiler breeds have had a greater propensity for changes in retro-peristalsis of the intestine in periods of mild stress leading to dysbacteriosis and wet litter. This is a big driver in antibiotic usage. The correct control of coccidiosis, which is always a challenge, also plays a major role in this area. At the parent level, and probably higher in the pyramid, we need to focus on the microbiome and in particular the intestinal microbiome and how and where changes in parental gut health can be passed to the broiler. A chick embryo at 17 days inside the egg has a gut flora and developing microbiome. Where did this come from and how do we help it develop into a healthy microbiome? This whole area is under major research by breed companies and the outcome of their work on gut health will be welcome in the near future.
But it is not all about the parent! Of course, the management of the broiler has to be of a very high level with absolute attention to detail and the farm manager has a major role to create a stable, controlled and suitable environment for the bird. Water quality and supply can still fail and the multitude of solutions available creates confusion and often lead to disillusion when testing shows water to still have high TVC. In this world, where the products are less regulated and where anyone can sell a solution, you need absolute confidence in your advisors and suppliers that they really know what they are doing. I often hear phrases on farm about what product is used for water treatment and its clear there is confusion and the wrong product at the wrong dose has been used wasting money, effort and importantly risking bird gut health.
Variations in the house temperature, humidity and ventilation will no doubt lead to stress in the bird, which clearly leads to changes in the gut bacteria. We see stress hormones changing some types of E. coli bacteria, making them more invasive leading to peritonitis, a condition that really needs good antibiotics if it is to be controlled. Monitoring the housing environment has to be in more detail and we have developed new sensor technology under Prognostix Ltd, which is purely focused on this area. Less antibiotics means better monitoring, both of bird health parameters and the environment, so that adjustments and treatments can be applied before it is too late. But this needs money.
Even with better monitoring and attention to detail there will be disease so we need to also have a range of alternative products to use. No one product, be it essential oil, short chain fatty acid, fimbriae blocker, quorum sensing inhibitor or whatever, replaces good antibiotics in the treatment of bacteria. A balanced range of products, tailored to the feed and husbandry system and monitored is the core requirement. There is no silver bullet.
Over the last decade, St David’s has moved heavily into these alternative products, and it is very clear that they bring with them a great range of different challenges. Unlike modern medicine, most of them are feed additives and as such, are less regulated, both in manufacture and in use. We are used to full detailed data sheets, having the confidence that, for example, one licenced amoxicillin is the same as another licenced amoxicillin in its activity and quality of production. Pharmaceutical companies have had to comply with, what some would say, is over regulation and the highest level of application of the precautionary principle. Now, we move to a much more under regulated world.
Don’t get me wrong, I am not asking for more regulation. This will, without a doubt, remove many products which we need if we are to achieve our goals in reducing antibiotics. For example, looking at essential oils as an example, some are manufactured in a semi-synthetic way with distillation to purify specific elements, whilst others are using the whole plant and suggesting that it’s the synergistic effect of the complete range of oils that gives better efficacy. As a supplier of many essential oils we have to be very certain we understand the sourcing of the raw materials, how they are manufactured and stored, as well as when and where to use them. Not every oregano is the same and for the best product you need to adopt the attitudes of the wine industry and look for the “terroir”. This is not easy for the farm manager who has to rely on what his supplier says.
Do not forget also that some plants can accumulate toxins such as pesticides if used, or heavy metals. Seaweed is the latest “new” product to be available in the UK and there is no doubt that from the right source, well managed and manufactured there are some interesting actions it can have in promoting good health, but also is a great way of accumulating heavy metals if the right product is not used. Investing time and energy in sourcing and fully understanding the provenance and production of many alternative products will be essential as we move to further antibiotic reduction.
We have the tools, the understanding of the holistic approach that is needed and we have the monitoring equipment and software to continue further down the road of antibiotic reduction. The issue is whether the consumer will pay for this higher quality product as there is no doubt that total removal of antibiotics, however you define them, will and does bring higher costs of production and greater risks to the farmer. Those promoting antibiotic reduction to a zero level need to be clear, what is the real agenda and if that’s for no animal production then don’t hide behind antibiotics.