Nitrogen use efficiency in global animal production systems 1970 – 2015

Global animal production increased considerably in the period 1970 – 2015. Global animal numbers have also increased but not as fast as animal production. Nitrogen use efficiency can be studied at three levels, namely animal level, farm level with animals, and regional level. This paper studies the effect of increased global animal production on the trend of nitrogen use efficiency. 

During the period 1970 – 2015, global animal production increased considerably: meat with 220%, milk from dairy cattle 80%, and eggs with 290%. Table 1 shows the increase of animal production per category for the years 1970, 1985, 2000 and 2015. The year 1970 was taken as the reference year. Table 1 also shows the increase in global animal numbers for the same period. Table 1 learns that the increase in animal production is always higher than the increase in animal numbers. In other words, production per head of animal has always increased during this period.