Discipline: environment: 

The Dairy Industry is committed to encourage sustainable and environmental friendly farming practices. A major contribution to this commitment is to limit greenhouse gas emissions which results in global warming (the major gas being methane) and therefore the industry endeavours to embark on a programme of mitigation, aiming to inform and train farmers. A few directives and guidelines adapted by the author from pages 302 and 303 of the publication referenced below, may be of value. These are:

Greenhouse gas emissions (and as a result the carbon footprint) can be reduced on-farm by:

  1. Improved production efficiency, which has the greatest potential of all methods. Although there are other factors, more milk per cow and therefore the same total milk yield with fewer cows is the most important factor. The reason is that although the higher producing cow will produce more methane in rumen fermentation, the amount of methane per litre milk will be less and because fewer cows are used to produce the same amount of milk, the overall methane emission will be lower.

  2. Associated with 1) herd composition is important. Dry cows and replacement heifers should comprise a comparatively small percentage as their methane production cannot be offset against the milk yield.

  3. Limiting cultivation of crop fields and pasture enclosures by introducing minimum or no tillage methods. The potential is good because minimum carbon is released and less fertilizer is used. The nitrogen in the fertilizer is converted into nitrous oxide which has a high global warming potential.

  4. Saving electricity by for example using energy-saving bulbs and solar power for household and water provision.

  5. Optimizing transport by less driving occasions and ensuring full loads in away and return trips. Also, by using vehicles in good state of operation and with less carbon emission (good fuel efficiency).

  6. Providing higher quality feeds. Feeds with higher digestibility such as grains, grain by-products, oilseeds, silage and immature pasture result in less methane being produced during rumen fermentation per kg feed than feeds with lower digestibility such as hays, mature pasture and straw. By providing well-formulated supplements to growing heifers and dry cows on feeds or pasture with lower digestibility, their digestibility will improve and less methane will be produced per kg feed.

  7. Using home-grown feeds and by-products from the human food chain such as hominy chop, wheaten bran, defatted maize germ and brewer’s grains rather than cultivated feeds such as maize and protein sources such as soybeans to support livestock production. Internationally, maize and soybeans are associated with altered land-use practices (cultivation) and therefore with limited carbon sequestration or storage possibilities.

  8. Including feed additives such as oils and fats and ionophores such as monensin in feeds. They reduce methane production during rumen fermentation, but the potential is modest. 


H.H. Meissner, M.M. Scholtz & F.A. Engelbrecht, 2013. Sustainability of the South African Livestock Sector towards 2050. Part 2: Challenges, changes and required implementations. S. Afr J. Anim. Sci. 43, 298-319.