Feed Intake by Lactating Goats in Confinement

Use this Feed Intake Calculator to calculate the daily feed intake for mature lactating goats. Enter the data into the table and then click the Calculate Feed Intake button. The results will be displayed in the table at the bottom of the page.


We will use a 50-kg dairy goat with 0 body weight (BW) change producing 3 kg of milk with 3.5 % fat and consuming a diet with 11 MJ/kg dry matter (DM) of ME.
1. Choose biotype of the goat meat, 50% or more Boer
indigenous or local
2. Enter body weight (kg)
3. Enter average daily gain (g/day)
4. Enter milk production (kg)
5. Enter milk concentration of fat (%)
Enter dietary ME concentration (MJ/kg DM)
You can use the TDN calculator below and the ME concentration will be entered automatically.
7. Enter % DM in diet (default is 90%)
To convert from English to metric system,
enter your values here.
They will be automatically entered into the table to the left.
Milk production


For example milk concentrations noted by Nsahlai et al. (2004) for different goat breeds and stages of lactation, click on this button:

To estimate the dietary ME concentration, often feed tags list the Total Digestible Nutrient (TDN) concentration. Likewise, most commercial feed laboratories estimate the TDN concentration based on various analyses, such as for crude protein and fiber fractions.

The ME concentration can be calculated with these simple formulas:
ME (MJ/kg) = TDN (%) × 0.15104 and
ME (Mcal/kg) = TDN (%) × 0.0361.

Enter TDN (%)
ME (MJ/kg)
ME (Mcal/kg)

The approach used to develop predictions of voluntary DM intake by goats was based on an assumption of constant overall efficiency of utilization of ME. Therefore, ME requirements from other studies of this project were employed, along with assumptions of efficiencies of ME utilization. In accordance, inputs necessary to predict intake entail factors influencing the partitioning of energy for use in various physiological functions, including production level. It is important to note that input of an unreasonably high level of production given the characteristics of the animal and nature of the diet will result in a comparable unlikely estimate of feed intake.

The concentration of crude protein (CP) in the diet did not have a significant effect on intake in the prediction equation development process. Therefore, accuracy of intake prediction is contingent upon the diet supplying adequate ruminally available CP for normal growth and digestion by ruminal microbes and an amount of metabolizable protein (MP) and array of amino acids absorbed in the small intestine sufficient to achieve the level of performance input.

Data on which this calculator is based were from goats in pens or stalls and not in late gestation or experiencing appreciable compensatory growth or effects of acclimatization. Correspondingly, adjustments of the maintenance ME requirements available in other calculators are not employed here. Therefore, caution should be exercised if using this calculator to determine if an estimate of feed intake based on a ME requirement calculator with the maintenance requirement being substantially affected by adjustments is likely or not. However, adjustments can be used with the Option B Calculator "Feed Intake with Adjustments of the Maintenance Energy (ME) Requirement - Lactating Goats".

The example prediction of DM intake with 3 kg of milk with 3.5% fat is 2.08 kg.

Predicted ME intake (MJ):
Predicted DM intake (kg):
Predicted DM intake (% BW):
Predicted as fed intake (kg):
Predicted as fed intake (% body weight):

The source used in this calculation method is:

Luo, J., A. L. Goetsch, I. V. Nsahlai, J. E. Moore, M. L. Galyean, Z. B. Johnson, T. Sahlu, C. L. Ferrell, and F. N. Owens. 2004. Voluntary feed intake by lactating, Angora, growing and mature goats. Small Ruminant Research 53:357-378.

Nsahlai, I. V., A. L. Goetsch, J. Luo, Z. B. Johnson, J. E. Moore, T. Sahlu, C. L. Ferrell, M. L. Galyean, and F. N. Owens. 2004. Metabolizable energy requirements of lactating goats. Small Ruminant Research 53:253-273