Lead Feeding – What is it and what are the benefits?

The transition period is identified as an 8-week period that involves the 4-weeks leading up to calving and the 4-weeks that follow as the cow enters lactation. Through this 8-week period, the cow is at an increased risk to disease, metabolic issues, weight loss and mineral deficits. We use this transition period as a time to condition the cow to be in optimum body condition to calve and enter the dairy by providing her with enough energy and protein to ensure that her rumen is functioning efficiently to drive milk production, good health and reproductive performance. This is where the role of lead feeding comes into play as it provides the cow with adequate protein, energy, anionic salts along with the trace minerals required throughout this transition period. A transition cow diet should consist of 120MJ/ME, 14%CP and have a DCAD equal to or below 0.

What is lead feed?
Lead feed is a combination of protein and starch grains mixed with anionic salts and trace minerals.  The anionic salts are a combination of negatively charged anions such as sulphate and chloride which will make the cows blood slightly more acidic. This is known as the DCAD (dietary cation-anion difference). The cow responds to this, mobilizing and absorbing more calcium in an attempt to buffer the acid in her bloodstream by increasing the number of anions and decreasing the number of cations (positively charged) such as potassium, sodium and calcium, to produce an overall diet that is as close to 0 or slightly negatively charged, through more anion charge present than cations. Hay, silage and pasture all have positive DCAD values but all vary within themselves and from farm to farm. The best way to determine the DCAD of a feed source is to get a DCAD feed test carried out.  A well-balanced diet can then be formulated through the use of lead feed and hay being used to make sure your cows are achieving as close to 0 or a slightly negative DCAD.

Illawarra’s tuck into some Springer 16 (Lead Feed)

The Benefits of lead feeding

1.     Reduce ruminal disruptions – Milking cows are very vulnerable to lactic acidosis and sub-acute ruminal acidosis (SARA) resulting from suppressed appetite and rapid introduction of grains/ concentrates. Papillae will be stimulated and elongated to increase their absorptive area to have better uptake and utilisation of minerals within the rumen. Microbial populations will be built up with starch utilising bacteria to lower the rumen pH and prevent the risk of SARA and lactic acidosis that can occur during early lactation.

2.     Minimise Macro mineral deficiencies – Mainly refers to calcium, magnesium and phosphorus. Milk fever and grass tetany (hypomagnesaemia) can result from conditioned deficiency where excess potassium reduces the capacity of the cow to maintain stable blood concentrations of calcium and magnesium

3.     Minimise lipid mobilisation disorder – Includes ketosis, pregnancy toxaemia and fatty liver. These diseases are all largely influenced by a failure to provide sufficient or effective energy source close to calving

4.     Avoid immune suppression – Often associated with lack of energy or protein intake. Micro-nutrients are often involved, including copper, selenium, zinc, iodine, vitamin D & E. Generally, very low incidences of cow health issues are experienced within the first two weeks post calving of cows that have been transitioned correctly, leading to lower culling rates and deaths during this period.

Springing cows chow down on lead feed.

TARGET RANGES TO AIM FOR