Grass-fed pasture-based systems support a more sustainable way of dairying

Our home is New Zealand, one of the best places in the world to farm grass-fed cows. Moderate temperatures, fertile soil, plentiful rainfall and abundant sunshine helps to grow lush green grass which cows graze year round. It’s thanks to our grass-fed, pasture-based farming system in New Zealand that farmers here are amongst the most emissions efficient producers of dairy in the world¹.

Science shows that New Zealand’s pasture-based system is very efficient from a water and fossil energy use perspective, when compared to other methods (housed/feedlot) of farming2. Free roaming, pasture-based cows get the majority of their water needs from the grass they eat. Housed cows have a greater proportion of supplementary feed in their diet, which has high fossil fuels requirements to cultivate, harvest and transport crops to the barns as opposed to cows grazing on paddocks.  

Our grass-fed pasture-based system can also support healthier soil and pasture biodiversity².  Housed systems will often rely on growing single crop species in a monoculture to support feeding cows. New Zealand's mixed pastures commonly have multiple species that serve different purposes and have a range of co-benefits².  For example, legumes like white clover are excellent at capturing atmospheric nitrogen, and converts into a form that helps all the pasture species to grow and provides protein in the cow’s diet. Where pastures have a good clover content this reduces the need for synthetic nitrogen fertiliser.

Diversity of pasture isn’t just found up top, grazed pastures also have more organic matter and carbon content in the soil than cultivated fields². This ensures that the soil has a better structure, increasing the amount of water and nutrients it can hold. Pastures also support healthy underground populations of earthworms and microbes, which help to break down the soil and contributes to soil health^3,4. Earthworms enhance soil nutrient cycling, making nutrients available through the soil and the pasture. Nutrient cycling is essential, as livestock can’t access nutrients like carbon and nitrogen directly.

Building on the farm-specific Farm Insights Report provided to all Fonterra farmers at the end of each year, a Greenhouse Gas module was included for the first time in 2020. The calculations allowed reporting of emissions at a per hectare basis (absolute emissions metric) and at a per kilogram of milk solids produced basis (intensity emissions metric). This data, along with other key on-farm performance metrics, helps to support farmers with the information required to make decisions and take actions on farm that will help increase efficiency. Collectively, farmers making efficiencies in their individual operations will help Fonterra to meet its climate target of a 30% intensity reduction in Scope 1 and Scope 3 FLAG GHG emissions from dairy from a FY18 base year.

Our belief is that from New Zealand’s low emissions starting point, our continued improvements, grass-fed pasture-based system, will make us the best choice for our customers. 

New Zealand grass-fed dairy, a better sustainability choice

References:

1. Journal of Dairy Science. (2022). Metabolic and production responses of dairy cows fed diets with brown midrib corn silage. Full text.
2. AgResearch Internal Report. (2020). Pasture-fed livestock production and products: Science behind the narrative, Report Number RE450/2020/071. Full text​ (AgResearch)​.
3. Dairy New Zealand. (2019-2020). Dairy New Zealand Annual Report 2019-2020.
4. Mee, J. F., & Boyle, L. A. (2020). Assessing whether dairy cow welfare is “better” in pasture-based than in confinement-based management systems. New Zealand Veterinary Journal, 68(3), 168-177. DOI: 10.1080/00480169.2020.1721034.