In the past, swine producers have used antibiotics and pharmacological levels of zinc oxide to control pathogenic infections and improve performance in newly weaned piglets. Whereas antibiotics have been closely regulated for many years to reduce the risk of antibiotic resistance in humans, the pharmacological use of zinc oxide via a veterinarian prescription was previously permitted and commonly used in the European Union (EU).
Although the nutritional requirement for zinc in weaned piglets is between 80 and 100 ppm, research has shown that pharmacological levels of 2,000 ppm or higher can suppress bacterial growth and mitigate or prevent diarrhea. As a result, these high levels of zinc oxide have been shown to improve growth performance.
As of June 2022, the use of pharmacological levels of zinc oxide in weaned piglet feed was banned in the EU. In France, the ban began already in January 2021. This means that the use of zinc for piglets is limited to 150 ppm total dietary zinc and swine producers will have to find new strategies for preventing bacterial infections and diarrhea on their operations.
Managing piglet health and nutrition before, during, and after weaning will be critical to success and will likely not be accomplished with a single, magical ingredient. Instead, it will require a complex approach with several alternatives supplied in feed and water and diligent management strategies to prevent problems from happening or minimize the impact on performance.
Why is Zinc Oxide Under Scrutiny?
Environmental Effects of Zinc Oxide
The main reason for this change is concerns over the environment and how much the piglets are excreting zinc. Since pig manure is used as fertilizer, high amounts of zinc are spread onto the soil and may affect the absorption of other trace elements such as iron and consequently influence the synthesis of chlorophyll by the plants. Other concerns raised are the accumulation of zinc in the liver of animals and in surface water.
Combatting Antimicrobial Resistance
This is very similar to the reason why the use of antibiotics in swine production has been limited. Recent studies showed that high pharmacological levels of zinc oxide may increase the proportion of multi-drug resistant E. coli in the gut of the piglets. Furthermore, Cu, Zn and antibiotic resistance genes co-exist in animal isolates of multidrug-resistant Salmonella and methicillin-resistant Staphylococcus aureus (MRSA). This genetic linkage of the resistance genes carries the potential for metals to impact antibiotic resistance development in animal and human pathogens.
Benefits of the Ban of High Levels of Zinc Oxide
Minimize Change of the Pig Digestive System
While high levels of zinc oxide can suppress the growth of harmful bacteria, they can also suppress the growth of beneficial bacteria, such as Lactobacilli, which is essential for normal gut function. Suppose the growth of these beneficial bacteria is suppressed. In that case, this could cause the normal microflora to be out of balance after the high levels of zinc oxide are removed from the diet, leading to further problems with diarrhea.
Maintain Phytase Efficiency of the Pig Digestive System
High levels of zinc oxide can also reduce the efficiency of phytase, an enzyme that is added to piglet diets to improve phosphorus digestion.
Swine Health Management Readiness for Alternative Zinc Oxide Levels
Healthy Pigs without High Levels of Zinc Oxide Need Increased Biosecurity Measures
Prevention is always the best — and usually the cheapest — way to manage bacterial infections. Therefore, strict biosecurity measures should be in place. This includes washing, disinfecting and drying pens after a group of pigs moves out and before the next group moves in. Downtime of the facilities between groups of pigs may be beneficial also. This will help limit piglet exposure to bacteria and pathogens from the previous batch. Make sure that feed trucks are prevented from entering the farm or sanitized before coming onto the operation for deliveries. Additionally, make sure that you and your staff are properly washing and disinfecting boots before entering and leaving each barn.
Healthy Pigs without High Levels of Zinc Oxide Need Steady Vaccination Protocols
Each swine operation has its own environment and unique problems. It’s important that you consider the health status of your herd and formulate a vaccination protocol around those challenges. Following a good vaccination protocol can limit or eliminate opportunistic bacterial infections and decrease your reliance on high levels of zinc oxide.
Healthy Pigs without High Levels of Zinc Oxide Need Ideal Climate Management
This is an area of swine production that needs more attention overall. It’s not just a matter of controlling the average environmental temperature, but also effectively managing variation between day and night temperatures to keep it as narrow as possible. A five- to 10-degree Celsius (8-16 degrees Fahrenheit) variation between day and night is simply too much for piglets and can cause additional stress that opens the door for bacterial infections.
Minimize Stress of Weaning Piglets with Feed Management
Weaning is a very stressful time for piglets, and many will not eat for the first several days postweaning. Properly managing feeding prior to weaning can help jump-start piglet feed intake immediately after weaning, ensuring that they are maximizing their zinc intake without needing pharmacological levels. One such way is to provide some solid feed to them before weaning so they know what it is, where it is and how to eat it when they are removed from the sow. Once they are weaned, you should aim to provide feed that smells and tastes like milk.
Formulate Swine Diets with Essential Organic Trace Minerals
Even without pharmacological levels of zinc oxide, you will still be able to formulate your piglet diets with up to 150 ppm of total zinc to support health and support the immune system. Feeding zinc from performance trace minerals, such as Zinpro® Availa® Zn, as a partial or complete replacement for zinc oxide, can improve the gut integrity and help the pigs to mount a rapid and robust immune response against bacterial challenges. This will promote improved growth and performance even in the absence of high levels of zinc oxide.
Improve Swine Health Management Today
The ban on pharmacological levels of zinc oxide began in France in January 2021 and the rest of the EU followed in June 2022. Swine producers are altering their piglet nutrition and management to improve herd health to manage through these changes.
To start the conversation about how you can begin making changes on your swine operation, contact your Zinpro representative today.
Ready for more? Check out part two of our series for a guide to post- zinc oxide guide to weaned piglet feed management.