Pre-calving mineral requirements

To achieve a successful transition, the management and nutrition of dry cows need to be right.

The success of the transition revolves around four key pillars: body condition score, nutrition, minerals and management.

These pillars will lead to a smooth, stress-free calving and set cows up for successful lactation by reducing metabolic issues around calving, including milk fever, retained placenta, displaced abomasum and ketosis.

As previously mentioned, one of the four pillars relates to correct mineral nutrition. Dry cows should be fed a dry cow mineral for the duration of the period (ideally between six to eight weeks).

This is to ensure there is a good reserve of minerals built up, allowing the cow to calve down without any issues and continue into the lactation to follow.

Looking at mineral requirements in more detail, we break minerals down into two key areas: major minerals and trace elements.

1. Major mineral

requirements

Magnesium is a crucial major mineral concerning the control of milk fever. Magnesium is necessary for the metabolism and absorption of calcium within the cow around calving. Throughout the dry period, a cow needs between 25–30g magnesium per day. As a general rule for anyone feeding dry cow minerals on-farm, if the feed rate of the mineral is 150g per head per day, there needs to be a minimum of 15–20% magnesium present.

Potassium in grass silage is typically between 1.8–2.4%. However, the dry cow requirement is only 0.52%. Potassium interacts with magnesium, locking it up in the rumen, which can slow down the absorption and mobilisation of calcium, leading to milk fever. With sufficient magnesium supplementation, the typical levels of potassium can be managed. If potassium is greater than 1.8% in silage, alternative measures need to be taken, such as introducing Cal-Mag or sweetened Cal-Mag.

Unless you are following a DCAD diet programme, grass silage can supply the calcium required during the dry period. This ensures that the cow mobilises calcium reserves within her bones and bloodstream, reducing the risk of milk fever.

2. Trace minerals during the dry period

Trace minerals, or micro minerals, play a massive role in supporting immune function, fertility and production of dairy cows. Throughout the dairy cow’s cycle, calving is the most stressful period on the immune system. It is vital that throughout the dry period, the cow can build up the necessary amount of trace minerals to allow her to draw from her reserves when she calves down.

Essential trace minerals are:

Selenium: Works with Vitamin E, acts as an antioxidant and helps support cow and calf immune function. Calves fed protected selenium in the form of Alltech’s Sel-Plex® are well-developed (heart, lungs, skeletal) and have a good suckling ability. Sel-Plex sets up the cow for the lactation to come and reduces the incidence of high somatic cell count (SCC) and mastitis in the following lactation.

Copper: Copper is involved in the creation of red blood cells. In its organic form, such as Bioplex®Copper from Alltech, it is key to maintaining successful immune function pre-calving and into the lactation to follow. Bioplex Copper also plays a key role in reproduction and hoof health as the cow begins the lactation cycle.

Zinc: The trace mineral that influences udder and hoof health in dairy cows. Zinc supplementation is essential at all times of the year as it helps to keep SCC under control, reduce incidences of mastitis and maintain the hardness of the hoof. During the dry period, Bioplex®Zinc from Alltech is key to supporting immune function.

Iodine: Low dietary iodine intake during pregnancy has been associated with an increased incidence of small and weak calves, increased incidence of goitre, decreased resistance to hypothermia, decreased survival and low immune function. In the following lactation, cows recycle poorly, which means that iodine is not stored in the body and so must be supplied in the diet.

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. They are also not reserved for times of stress, such as calving or disease. The minerals contained within forages (for example, grass silage) are in an organic form, but these forages are deficient in the level the cow requires. Feeding additional trace minerals in their organic forms— such as Bioplex Copper, Zinc and Sel-Plex— leads to these minerals being absorbed at higher levels, stored and utilised by the animal. This helps to build the cow’s immune system, supports her during stressful times and helps overall cow performance.

To discuss options for implementing a successful dry cow programme this season, get in contact with Alltech today.

Make your dry cow minerals count, Bioplex and Sel-Plex trace minerals can be included in your dry cow premix or concentrate.

If you would like more information about Bioplex and Sel-plex from Alltech, contact Richard Dudgeon on 07739745379.