Excretion of nitrogen and organic matter in cattle manure: an evaluation of Nex and VS models from Norwegian dairy cows and growing cattle

The purpose of this report is to evaluate current models for calculating the amount of manure
and the excretion of nitrogen in feces and urine in dairy cows and growing cattle.

The report also proposes revised models for calculating the excretion of volatile solids of organic matter in different cattle categories.

The report also provides suggestions for possible improvements to future models. With the exception of heifers for slaughter, it is recommended to continue the current nitrogen models from NIR 2021 for dairy cows, breeding heifers and slaughter bulls.

For heifers for slaughter, new models are recommended. Revised models are proposed
for calculation of volatile solids excreted in feces and urine. The report also proposes various
measures to improve future models.

Dette er en korrigering og endring av en rapport som er publisert tidligere.