A survey of calf management practices and calf mortality in dairy herds in Finland

Good care practices and colostrum feeding of newborn calves are important for a calf's future health and growth. This study aimed to determine cow calving and calf care practices, focusing on factors affecting calf mortality within the first week (including stillbirth) and from 1 wk to 3 mo of age on dairy farms in Finland. Our research used an online survey designed based on the literature and management practices and distributed to dairy farms via farm information channels, social media, and direct communication with veterinarians. Data were collected from September 2021 to December 2022, yielding 186 complete and usable farms for analysis. The online survey covered questions on basic farm information, calving observation, colostrum management, and calf care, along with production and mortality data. The farmer provided all data used in the study by completing the questionnaire. The responses were processed, and statistical analyses were performed using logistic regression models to identify predictors of calf mortality in calves aged less than 1 wk, including stillbirths (median mortality 4.1%), and calves aged from 1 wk to 3 mo (median mortality 1.3%). The results showed that larger herd sizes (more than 75 cows) were associated with increased mortality in both age groups (odds ratio [OR] = 2.7, 95% CI 1.3-5.9; and OR = 2.3, 95% CI 1.1-5.0, respectively). For calves less than 1 wk old, mortality was higher in insulated barns (OR = 2.1, 95% CI 1.0-4.7), when fed less than 3 times daily (OR = 2.3, 95% CI 1.1-4.8), and when no hay or straw was used as bedding (OR = 2.5, 95% CI 1.0-6.8). The mortality rate for calves aged less than 1 wk was higher on farms using a group pen for calves after separation from the dam or an automatic milking system (AMS) for the first colostrum harvest;the OR for group pens housing 2 to 4 calves compared with single pen was 2.7 (95% CI 1.0-7.7) and the OR for pipeline or parlor milking of the first colostrum compared with AMS was 0.3 (95% CI 0.1-0.7). In calves aged 1 wk to 3 mo, mortality was higher on farms using AMS as the main milking method; the OR for both, parlor and pipeline milking was 0.3 (95% CI 0.1-0.8), and the OR for feeding low-quality colostrum was 3.4 (95% CI 1.3-9.6). Mortality in calves aged 1 wk to 3 mo was lower when the farm could store colostrum in the refrigerator or a cold bath (OR = 0.5, 95% CI 0.2-1.0). This study highlights the importance of herd size, barn type, milking methods, and colostrum management in calf survival, providing valuable insights into improving dairy farm management practices. Despite the relatively low number of farms included, the findings offer guidance for dairy farmers and veterinarians aiming to enhance calf care and reduce mortality rates on dairy farms.