Feed efficiency measures biological output of dairy cattle, the amount of energy-corrected milk per kg of feed consumed. It is calculated by dividing the amount of energy-corrected milk (ECM) by the dry matter intake (DMI). Sometimes the diet that has the highest feed efficiency is also more profitable, but this is not always the case. Production efficiency looks at the biological output per amount of money spent on feed. Production efficiency of dairy cows is sensitive to both changes in feed efficiency and changes in ingredient costs. It is therefore more predictive of dairy farm profitability than feed efficiency.

Energy requirements of a dairy cow double in the period immediately after calving117, 118. As a result, the demand for glucose increases above the supply (see Figure 1). Propionate is a key source of energy for dairy cows. More energy from propionate in the rumen increases production efficiency of cattle, providing dairy nutritionists and producers with options to increase herd profitability.

Selko Renergy can be used to increase feed efficiency of dairy cattle by increasing the amount of milk produced out of their diet. Alternatively, Selko Renergy can be used to increase production efficiency of dairy cattle by adding it to the dairy diet and replacing expensive dairy feed ingredients with cheaper alternatives.

Option 1: Add Selko Renergy on top of your diet to increase milk production

Add Selko Renergy on top of the existing diet to increase energy available for milk production. Add Selko Renergy to the diets for:

• Fresh cows
• High yielding groups of cows
• Transition cows

Option 2: Reformulate your diet to lower feed costs

Feeding Selko Renergy allows you to reduce the amount of expensive, energy-dense ingredients in the diet and replace the space with lower-cost ingredients like forages. Replace costly, energy-dense ingredients in the diet such as:

• Rumen available fats
• Rumen by-pass fats
• Starch sources like corn

An in-vivo trial was carried out by the Colorado State University to measure the impact of Selko Renergy on the production of volatile fatty acids in the rumen of steers on a diet with high levels of grain119.

Material and methods

Two groups of 4 ruminally canulated steers each were fed a high concentrate diet. One group was fed Selko Renergy at the recommended dose, the other group served as a control group. After 28 days of feeding Selko Renergy, VFA profiles and lactic acid levels were compared between the group of cattle fed Selko Renergy and the controls.

Results

Adding Selko Renergy to the diet resulted in a significant increase of total VFA by 13.3% and propionic acid by 25.7%. L-Lactate production tended to be decreased by 25.1% (see Figure 3).

Figure 3: Total production of VFA, production of propionate and production of lactate in steers fed Selko Renergy compared to untreated controls receiving the same diet.

Three performance trials in lactating dairy cows were carried out.

Trial in transition cows

A total of 72 dairy cows were included in this trial to assess the impact of feeding Selko Renergy during the close-up, prepartum, and transition period until 28 days in milk. The four groups were:

• Selko Renergy fed only prepartum

• Selko Renergy fed only postpartum

• Selko Renergy fed both pre and postpartum

• Control group without Selko Renergy

Production of energy corrected milk (ECM) was significantly improved by 5.34 kg (p = 0.05) per day in the group of animals fed Selko Renergy both pre and postpartum, 3.12 kg (p = 0.02) per day in the group fed Selko Renergy only postpartum and 2.2 kg (p = 0.10) per day in the group fed Selko Renergy only prepartum.

Trials in early and mid-lactation cows

Two trials were carried out in early and mid-lactation cows. In the early lactation trial, 66 cows were included, half of them was fed Selko Renergy and compared to controls fed the same TMR, but without Selko Renergy. In the mid lactation trial, 28 cows were included. All cows included in the trial were fed the same TMR, half of them with, the other half without Selko Renergy. In both trials, the amount of Fat Corrected Milk was compared between the cows fed Selko Renergy and the controls (see Figure 4).