Approximately one in ten calves die before reaching seven months of age in dairy farming. During a webinar organized by Littoral Normand, advisors and veterinarians discussed the main causes of calf mortality and practical solutions to reduce losses, which pose both technical and economic challenges for farmers. "The calf is the only income in dairy farming," recalls Gabriel Fougère, a Littoral Normand advisor during the webinar. So, it's crucial to preserve them. With an 8.9% mortality rate across all breeds nationally, the industry still has room for improvement. "Mortality is often underestimated by farmers. However, prices make it impossible to tolerate very high loss rates," estimates the advisor. The alert threshold for calf mortality is set at 7%. The Parthenaise breed has the highest mortality rate during the 0-7 months period, at 14.1%, closely followed by the Rouge des Prés at 14%. In contrast, rustic breeds such as Aubrac and Salers have lower mortality rates, at 7% and 7.7%, respectively. According to Fougère, "the alert threshold is at 7%." For example, with a herd of 60 cows, it is advisable to be concerned if losses exceed four calves per year. "With 60 dairy cows, if the mortality rate is 9.9% with an alert threshold at 7%, it results in a loss of nearly 5,000 euros in the dairy operation," calculates Gabriel Fougère. Prevention begins before calving. The 0-3 days period is the most critical, accounting for 54% of total calf mortality, often due to difficult calvings or lack of supervision. Littoral Normand veterinarian Jean-Michel Cuminet also advises considering late abortions. "It is also necessary to take into account calf mortality a few weeks before the mother's due date," he says, recommending attention to abortive diseases. Vaccines exist for conditions such as BVD, Q fever, and IBR. Neosporosis can also cause abortions, and affected farms must be vigilant about managing delivery to prevent dogs from licking calves or coming into contact with cattle feed. The quality of forage is also important, as a third of abortions are of mycotic origin. Therefore, avoiding mold and ensuring clean water is essential. Gabriel Fougère also emphasizes the importance of mineral supplementation for pregnant cows, recommending 150 g of CMV in the month before calving. Monitoring tools can also help farmers intervene when necessary. The 3-30 days period accounts for 21% of calf mortality, often due to diarrhea or large umbilical cords. Preventing this requires monitoring colostrum intake, which provides essential immune defenses. Jean-Michel Cuminet suggests vaccinating mothers to protect against diseases such as rotaviruses, coronaviruses, E. coli, salmonella, and cryptosporidiosis. These vaccines help transfer immunity to calves through colostrum. The umbilical cord is another point of concern, as it can be a potential entry point for bacteria. Disinfecting it is recommended, although some mothers may lick their calves' cords, introducing bacteria. The level of environmental hygiene can influence the need for disinfection, and using chlorhexidine-based products may be beneficial. Ensuring proper calf housing and thermal comfort is also important, as low temperatures can cause stress. Heating lamps may be necessary if calves have experienced difficulties during calving.