AgriSearch have just published their 23rd farmers’ booklet. This booklet features the results of a series of five experiments conducted to examine ‘novel supplementation strategies’ which were designed to reduce negative energy balance in early lactation.
Today’s high-yielding Holstein dairy cows are unable to consume enough food to meet their increased energy requirements for milk production. The resulting negative energy balance in early lactation has been associated with a decline in ‘functional traits’ such as health and fertility, and an increase in involuntary culling rates.
It is generally accepted that reducing the extent of negative energy balance (minimising loss of condition) in early lactation should result in improved cow health and fertility. To address this, a series of five experiments were conducted to reduce negative energy balance in early lactation.
These examined the following important issues:
1. The effects of pre-calving and post-calving energy intake on feed intake, milk production, energy status and fertility.
2. Options to improve the energy balance of individual dairy cows through short term changes in dietary protein levels.
3. If the inclusion of protected methionine allows the protein content of the diet to be reduced without any loss of performance, and to examine the impact of this on the efficiency of nitrogen utilisation.
4. If the reproductive performance of Holstein dairy cows could be improved by offering a diet to promote early cycling (early oestrus) and improved embryo survival.
5. The effects on food intake, milk production, body tissue reserves and cow fertility of introducing additional concentrates into the diet of dairy cows at week-3, week-7 and week-11 post calving.