UK soils are typically rich in iron, with it being the fourth most abundant element found in soil, and levels in excess of 100mg /kg DM quite typical. This means that iron requirements for ruminants are more than met by grazing and preserved forages such as hay or silage. Of course iron is an important nutrient, with it’s main role being linked to haemoglobin in the blood and transfer of oxygen to the tissues. Therefore, surely although the animal is already getting enough in their diet, won’t it help them to add some more. Or should we be considering the adage ‘it is possible to have too much of a good thing’?

The simple answer is, ‘Yes’, the thinking farmer will avoid adding additional iron to their flock, if they want to truly maximize animal production.

Excess iron is not easily excreted by ruminants, and will accumulate in the liver where it can lead to iron toxicosis. However, long before we reach toxic levels we can see negative impacts on animal health and production. Excess iron limits the uptake of other dietary elements, particularly key nutrients such as copper and zinc. Recent research shows that excess dietary iron damages the immune function of sheep, reducing levels of the body’s key antioxidant, glutathione, and lowering overall antioxidant capacity(1), and negatively impacted nutrient digestibility, rumen fermentation and bacterial communities in sheep(2).

To avoid the deficiencies and imbalances commonly seen with these nutrients, not only do we need to ensure we are providing appropriate drenches (with or without copper) at key times; but just as importantly is to ensure we are not upsetting nutrient uptake by overproviding iron.

Within the UK it is advised to leave iron provision to the forage alone, and instead ensure optimal nutrition is provided with broad spectrum drenches, such as Greencoat Farm Vit & Min. For targeted nutrition to support health and vitality, particularly in young and finishing lambs, we advise Greencoat Farm Maxithrive B12, providing natural bioavailable cobalt from Vitamin B12, with broad spectrum B vitamins, and the antioxidants A, E and selenium. Natural cobalt from Vitamin B12, also known as cobalamin, is preferable to using supplements containing high levels of synthetic cobalt. Vitamin B12 is the natural form of cobalt and so naturally bioavailable, meaning feeding excessive levels is not necessary. Vitamin B12 products are also safer to use, as the synthetic cobalt compounds are considered to be carcinogenic, and therefore a risk to both you and your farm staff in the long-term.

1. Liu et al (2020) Effects of different doses of excessive iron in diets on oxidative stress in immune organs of sheep. Biological Trace Element Research. Oct 197(2) 475-486 2. Wang et al (2020) Effects of over-load iron on nutrient digestibility, haemato-biochemistry, rumen fermentation and bacterial communities in sheep. Journal of Animal Physiology and Animal Nutrition. Jan 104(1) 32-43