{"id":23490,"date":"2026-11-04T10:38:42","date_gmt":"2026-11-04T10:38:42","guid":{"rendered":"https:\/\/www.topro.nl\/topro-kennisbank\/begrippenlijst\/replacement-rate\/"},"modified":"2026-11-04T10:38:42","modified_gmt":"2026-11-04T10:38:42","slug":"replacement-rate","status":"publish","type":"farmula_glossar","link":"https:\/\/www.topro.nl\/en\/topro-kennisbank\/begrippenlijst\/replacement-rate\/","title":{"rendered":"Replacement rate"},"content":{"rendered":"

What is herd replacement?<\/h2>\n

Herd replacement means topping up the dairy herd. Cows that leave the farm are replaced by heifers. These heifers come from your own rearing, from outsourced rearing or are bought in when in calf.<\/p>\n

The replacement rate<\/h2>\n

The replacement rate is the share of the herd replaced by heifers in one year. The calculation is simple:<\/p>\n

Replacement rate = number of heifers entering the herd per year \/ average number of cows x 100<\/p>\n

An example: a farm with 100 cows brings 33 heifers into the herd in a year. The replacement rate is 33 per cent. The cows then stay in the herd for only about three lactations on average. Many farms in Germany are between 30 and 40 per cent.<\/p>\n

Closely related is the culling rate: the share of cows that leave the herd each year. With a constant herd size, both are the same. If the herd grows, the replacement rate is higher.<\/p>\n

Why does the rate matter so much?<\/h2>\n

In the German state of Schleswig-Holstein, rearing a heifer up to first calving cost \u20ac2,659 on average in 2024. A cow often only earns these costs back in her second lactation. If she stays for just three lactations, the profitable period is short. Every extra lactation lowers the rearing costs per litre of milk.<\/p>\n

A worked example from practice: if the productive life on a farm with 100 cows rises from three to five lactations, 13 fewer heifer calves are needed. That alone saves about \u20ac21,000 in rearing costs per year. Because there is less youngstock on the farm, you can produce more milk within the same phosphate limit. You will find the full calculation in Aim for two more lactations<\/a>.<\/p>\n

Voluntary and involuntary culling<\/h2>\n

Not every cow leaving the herd is a bad sign. Voluntary culling, for example because of low yield or genetic progress, is part of management. Involuntary culling is the problem. In seven out of ten cases, a cow does not leave the herd by choice. The most common reasons are:<\/p>\n