Key facts about zinc
Zinc in a nutshell
Zinc is an essential trace element in animal feed and therefore worth taking a closer look to its’ special characteristics: The many functions of zinc indicate the importance of a needs-based care for the health, fertility and performance of animals. Eyes, bones, liver and hair are especially rich in zinc.
But other processes such as the production of enzymes and a functioning gut barrier are also dependent on zinc. A deficiency leads among other effects to reduced feed consumption and poor growth in many animals. Zinc additives are therefore an indispensable part for many mixed feeds.
History of zinc-supply in piglets
Concerning pigs, probably the most sensitive stage of their breeding together with farrowing is weaning, a sudden and extremely stressful moment (Campbell et al., 2013). To avoid post-weaning diarrhea in piglets, pharmacological dosages of zinc oxide in the dimension of 2000 – 3000 ppm have shown good effects in the past but also carry risks.
The use of pharmacological levels of ZnO in piglets has raised several concerns, which main issue is related to the considerable risk for the environment derived from the application of Zn-rich manure to land as a non-volatile and non-degradable heavy metal (Jensen et al., 2016). Another worry is related to its’ toxic effects (Burrough et al., 2019) because of the excessive accumulation of Zn in animal tissues such as kidney, liver, and pancreas (Komatsu et al., 2020). In addition, several studies proved that supplementation of pharmacological zinc oxide in piglets might also contribute to the acquisition and spread of antibiotic resistances (Yazdankhah et al., 2014).
Together with a considerable increase of multi-resistant E. coli strains (Ciesinski et al., 2018), pharmacological zinc oxide dosages are putting any potential antimicrobial activity of both antibiotic and zinc at risk. Finally, the impact of ZnO on the intestinal microbiota reveals remarkable effects on porcine microbial populations (Vahjen et al., 2011).
Legislation is changing all over the world!
Still, there are plenty of countries all over the world using pharmacological dosages of zinc oxide up to 3000 mg/kg final feed. Knowing about the impacts, more and more countries are discussing the usage of high amounts of zinc in feed and are preparing future bans.
EU-ban of veterinary zinc-products from June 2022
The decision not to allow further marketing authorizations for veterinary zinc-products has been taken in 2017 already. The five-year transition period for zinc as a veterinary medicinal product will end in June 2022, following the legislation of 2017. Veterinary zinc-products that are used to treat post-weaning diarrhea are then no longer available. To cover the essential requirement, a zinc-content of max. 150 mg/kg will still be permitted in piglet feed.
New advanced feed concepts request zinc supplements in accordance to current feed law restrictions. MIAVIT can look back on many years of experience in the field of "medicinal ZnO-free diets", offering a powerful solution called MiaTrace Zn. MiaTrace Zn aims to meet the physiological demand of the animals and to support overall intestinal health in the best possible way.
Learn more about MiaTrace Zn and watch the following video:
Zinc in modern piglet nutrition - Part II
Burrough, E. R., De Mille, C., & Gabler, N. K. (2019). Zinc overload in weaned pigs: tissue accumulation, pathology, and growth impacts. Journal of Veterinary Diagnostic Investigation, 31(4), 537-545.
Campbell, J. M., Crenshaw, J. D., & Polo, J. (2013). The biological stress of early weaned piglets. Journal of animal science and biotechnology, 4(1), 1-4.
Ciesinski, L., Guenther, S., Pieper, R., Kalisch, M., Bednorz, C., & Wieler, L. H. (2018). High dietary zinc feeding promotes persistence of multi-resistant E. coli in the swine gut. PLoS One, 13(1), e0191660.
Jensen, J., Larsen, M. M., & Bak, J. (2016). National monitoring study in Denmark finds increased and critical levels of copper and zinc in arable soils fertilized with pig slurry. Environmental Pollution, 214, 334-340.
Komatsu, T., Sugie, K., Inukai, N., Eguchi, O., Oyamada, T., Sawada, H., ... & Shibahara, T. (2020). Chronic pancreatitis in farmed pigs fed excessive zinc oxide. Journal of Veterinary Diagnostic Investigation, 32(5), 689-694.
Vahjen, W., Pieper, R., & Zentek, J. (2011). Increased dietary zinc oxide changes the bacterial core and enterobacterial composition in the ileum of piglets. Journal of animal science, 89(8), 2430-2439.
Yazdankhah, S., Rudi, K., & Bernhoft, A. (2014). Zinc and copper in animal feed–development of resistance and co-resistance to antimicrobial agents in bacteria of animal origin. Microbial ecology in health and disease, 25(1), 25862.