Reducing greenhouse gas emissions of New Zealand beef through better integration of dairy and beef production

Integrating dairy and beef production offers opportunities to reduce greenhouse gas (GHG) emissions of beef production, which is dominated by emissions related to maintenance of the breeding cow. This study aims to quantify the GHG reduction potential of the New Zealand (NZ) beef sector when replacing beef breeding cows and their calves with dairy beef animals. To this end, we combined a cattle herd model of NZ beef and dairy production with GHG emission calculations of beef production. We computed GHG emissions (to farm-gate stage) of the current amount of beef produced, while increasing the number of dairy beef calves at the expense of the number of suckler-beef calves. GHG emissions were 29% lower per kg carcass weight for dairy beef animals compared to suckler-beef animals. The average emission intensity decreased from 21.3 to 16.7 kg CO2e per kg carcass weight (−22%) as the number of suckler-beef animals declined to zero and dairy beef animals increased. Integrating dairy and beef production would enable the NZ beef sector to reduce annual GHG emissions by nearly 2000 kt CO2e (i.e. 22% of the total sector's emissions), while the dairy sector would improve their social licence to operate by reducing the number of surplus dairy calves slaughtered from 4-days old.