Animal groups at higher risk of mastitis are: Fresh cows (up to 30 DIM) Heifers (first 2-3 months of lactation) – check mineral supply, udder oedema and stress   Furthermore, any animal with a reduced resistance due to underlying disease or feeding errors (ruminal acidosis) is at increased risk of mastitis. This can be checked by assessing the feed intake (rumen fill, feed selection), digestion (manure score) and body condition score. Advise your farmer to give particular attention to fresh cows and heifers, and to regularly check the other animals as well (rumen fill, manure score, body condition score). On farms with milk robots, farmers should regularly check the udder health of the herd (palpate all quarters for heat and swelling). You can also use milk record data. For example, you can define attention cows based on the following: cows with a SCC > 250.000/ml (first lactation cows > 150.000/200.000/ml) cows with the highest recurrence of high SCC in the past 12 months; cows with more than 2 cases of clinical mastitis last 12 months.