Emission reduction activities in the Livestock Footprint target area can achieve emissions reduction in the following ways:

• Improving fodder quality through pasture rejuvenation with legumes or herbs
• Directly reducing enteric methane production with methane inhibitors provided as feed supplements

To estimate emissions reduction from livestock target activity you will need the following data:

DMI = Dry Matter Intake (kg)

The simplified estimates below are provided for initial calculations of emission reduction. They do not represent the requirements for reporting an enterprise baseline for other purposes.  For these purposes GHG accounting tools should be used.

Assumed livestock daily emission – business as usual

The following simple calculation can be used to estimate the kg CO₂-e based on a proportion of dry matter intake¹.

GHG_BAU = 0.58 * DMI

This estimate can be used as a baseline against which emissions reduction activities can be compared. Avoided emissions can be estimated via the avoided emissions equation:

GHG_avoided = GHG_BAU - GHG _activity

Pasture Rejuvenation – legumes & pastures

Estimates of methane reduction from improved fodder are only available where DMI is 100% legume/herb composition^2-6.Partial intake of enriched pasture is poorly documented.

For estimation purposes however, we can assume following calculations can be used as simple indicators of potential emissions reduction based on legume enhanced pasture:

GHG_activity=0.58 * DMI * (1-prop*0.0025)

Where: prop is the percentage of legume in diet by dry weight. This means that for every percent increase in legume in the diet there is a ¼ percent decrease in methane emissions up to a 25% decrease.

Methane inhibitors – feed supplements

The level of methane reduction achieved when using feed supplements depends on the type of inhibitor and dosage rate. For estimation purposes we can use emissions reduction factors in the table below, with the residual factor assuming dosage requirements have been met.

Therefore, to estimate of daily emissions from livestock where methane inhibitors are used at the appropriate dosage.

GHG_activity= 0.58 * DMI * RF

Where: a Residual Factor (RF) specific to the chosen methane inhibitor, and specified dosage rate is provided in the table below for simple estimation purposes.

1 Stifkens A et al. (2022) Animal Production Science, 62(7), 622–632. doi:10.1071/AN21576

2 Stifkens A et al. (2022) Animal Production Science, 62(7), 622–632. doi:10.1071/AN21576

3 Charmley E et al. (2016) Animal Production Science 56 169-180 doi.org/10.1071/AN1536

4 Meyer, R., Shaw, J., Cheng. P and Eckard, R. (2022) Options for mitigating greenhouse gas emissions in Australian dairy farms: Costs, benefits, risks and opportunities. University of Melbourne and Point Advisory December 2022.

5 Badgery W et al. (2023) Crop & Pasture Science, 74(7–8), 661–679. doi:10.1071/CP22299

6 Eason, C. T., & Fennessy, P. F. (2023). Methane reduction, health and regulatory considerations regarding Asparagopsis and bromoform for ruminants. New Zealand Journal of Agricultural Research, 1–30. https://doi.org/10.1080/00288233.2023.2248948