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Relative value of feed efficiency to reduce greenhouse gas emission along the dairy chain in the Netherlands - Deep Sapkota

There is a worldwide concern about greenhouse gas (GHG) emissions related to dairy farming. Among the different genetic traits in dairy cattle, feed efficiency is an important one. Increasing feed efficiency in dairy cows increases the economic performance and decreases the environmental impact of dairy production. The objective of this research was to evaluate the impact of one genetic standard deviation improvement in feed efficiency by using a whole farm optimization model.

There is a worldwide concern about greenhouse gas (GHG) emissions related to dairy farming. Breeding and feeding strategies can contribute to reducing these emissions. Among the different genetic traits in dairy cattle, feed efficiency (FE) is an important one. Increasing FE in dairy cows increases the economic performance and decrease the environmental impact of dairy production. Increasing FE, however, can affect the diets of dairy cows, farm production plan and farm management. Therefore, the objective of this research was to evaluate the impact of one genetic standard deviation improvement in FE by using a whole farm optimization model. FE of dairy cows was increased, and included in the model. Then, farm management was optimized based on two different objectives a) maximizing labor income and b) minimizing GHG emissions. The impact of increasing FE on labor income and GHG emissions was evaluated by comparing the results with the reference situation improving FE.

Results revealed that introducing FE, reduced the energy and protein requirement of the dairy cow, changed the farm production plan and reduced GHG emissions. Based on a) maximizing labor income, change in the farm plan resulted in 177 dairy cows, while further intensification was restricted by P application standards. Labor income increased by €63 per cow per year and GHG emissions reduced by 25 kg CO2e/t FPCM. Based on b) minimizing GHG emissions, change in the farm plan resulted in 187 dairy cows. Further intensification was restricted by manure application standards. GHG emissions were reduced by 59 kg CO2e/t FPCM. This reduction is more than two times higher than the reduction based on maximizing labor income. The results of FE were compared with other traits like milk yield and longevity. Milk yield becomes a choice of trait when the objective is maximizing labor income, whereas FE becomes the choice of trait when the objective is minimizing GHG emissions. FE was found to be the most promising trait for reducing GHG emissions. However, selection of traits depends on the farmers and breeding organization’s breeding goal.


Student: DN Sapkota

Supervisor: dr ir C van Middelaar

36 Ects