The article explores the possibilities of monitoring negative energy balance (NEB) in dairy cows in early lactation using precision farming tools. During the experiment with 83 dairy cows, feeding behaviour was monitored using automated sensors and blood and milk samples were collected during the early lactation period at the time of milk yield control. The results show that dairy cows with NEB exhibit reduced rumination time and higher levels of several fatty acids in milk fat, which might serve as an early indicator of NEB. In conclusion, monitoring feeding behaviour and measuring minor components of milk can play a key role in the prevention and treatment of NEB in dairy cows, thus contributing to the overall efficiency and sustainability of dairy cattle farming.