Minerals are often overlooked in a dry cow diet in terms of quality and quantity. It’s important to note that the mineral status of our forages can vary significantly. A mineral analysis is the only accurate way to know the mineral status of your forage to allow you to make an informed choice of an appropriate mineral supplement. Mineral labels can be difficult to interpret, and farmers may not be fully aware of what minerals are being supplied. To ensure the cow is getting what she needs, ask your supplier what the daily mineral supply is, as well as what form the minerals are in.
On many farms throughout the country, producers are using minerals containing inorganic salts of trace minerals, such as sodium selenite and copper sulphate. However, this form of trace mineral is not what the animal has evolved to use. The soil contains inorganic minerals, which are then taken up by the plant (e.g. grass) and converted to organic forms of minerals. The animal then eats the plant containing minerals in this organic form. Inorganic minerals cannot be stored by the animal and, therefore, do not allow mineral reserves to be built up for times of stress, such as calving or disease.
Feeding trace minerals in their organic form such as the Bioplex range of chelated organic trace minerals copper and zinc and Sel-Plex, an organic form of selenium from Alltech, lead to these minerals being absorbed at higher levels, stored and utilised by the animal. This helps to build the cow’s immune system and offers her greater protection from metabolic diseases during stressful times and helps improves overall cow performance, such as supporting udder health and reproductive function (Figure 1).
Feeding Bioplex and Sel-Plex minerals has also shown to reduce age at calving for first-lactation heifers by 26 days, who’s dams were fed these minerals during the dry cow period compared to dam’s fed a control (Figure 2).