Phosphate output from livestock manure down again

Reduced cattle herd

Between 1 January 2017 and 31 December 2018, the number of dairy cows declined by over 190 thousand or 11 percent. The number of calves, weanlings and heifers declined by over 300 thousand or 25 percent over this period. In 2017, the phosphate reduction plan for the dairy sector came into force. Considerable reductions in dairy herd size have been made as a result of this plan and the implementation of tradable phosphate rights as of 1 January 2018.
As of 2017 dairy farms are forced to dispose of dairy cows and female yearlings. In addition, nearly 600 out of the approximately 16 thousand dairy farms have announced closure.

Lower phosporus content in dairy cattle feed

Aside from herd reductions, the phosphate reduction plan has also led to a reduced content of phosphorous in compound dairy cow feed. The phosphorus content declined from 4.3 grams per kg in 2016 to 4.1 grams per kg of compound feed in 2018, a decline by over 4 percent.

In 2018, the phosphorus content of grass and maize - another common type of forage for dairy cattle - was at lower levels than in years previously.

Less phosphate production on pig farms

Phosphorus production by pigs declined slightly in 2018 due to a small decrease in the number of fattening pigs. Phosphate production in the pig farming industry came to 37.3 million kg in 2018.

Pig farmers were encouraged to switch to feed with lower phosphorus content as part of the phosphate reduction plan for pig farms <toelichting>. This contributed to a decline in phosphate production in the pig farming industry. Partly as a result of these measures, phosphate production has fallen below the 39.7 million kg production ceiling in recent years.

More phosphate production by laying hens, less by meat poultry

In 2018, phosphorus production by the egg-producing poultry sector rose by 4 percent year-on-year to 21.1 million kg. However, in the meat poultry sector, phosphorus production rose by nearly 10 percent to 6.5 million kg. These changes in phosphorus production were primarily the result of a new poultry registration system. In the 2018 Agricultural Census, the farmer’s own registration was replaced by a census method based on the Livestock identification and registration system for poultry (the Poultry Flock Information System or KIP, tr.). The change in census method is likely the reason for the trend break in the number of broilers.

In 2018, the number of laying hens rose by 3 percent to 47.7 million while the number of broilers decreased by 10 percent to 43.2 million animals. Total phosphoruse production by poultry was just over 1 percent above the phosphate ceiling of 27.4 million kg.

Phosphorus production in the remaining animal categories, e.g. sheep, goats, horses, ponies, rabbits and furred animals increased by 0.6 million kg to 7.3 million kg (2018), partly as a result of increased numbers of sheep and dairy goats.

Increased milk production per cow and higher nitrogen content in roughage

The level of nitrogren excretion in the dairy sector dropped slightly in 2018 to 292.8 million kg. This was still 303.5 million kg in 2017.

Milk production per dairy cow grew from over 8,300 kg in 2016 to 8,850 kg in 2018. Feed consumption per dairy cow grew as well. Over the past few years, the dairy cow’s diet has had a proportionally higher content of grass and feed concentrates due to increased feed consumption and a decline in the cultivation area for forage maize. Grass and concentrates contain up to three times more nitrogen compared to forage maize and thus in higher nitrogen emission levels per cow. Furthermore, the nitrogen content of grass has gone up in recent years. Therefore, despite a reduction in herd size, total nitrogen emissions have barely decreased.