Schuenemann and Piñeiro (2025) performed an observational study of the effects of transportation of dairy and dairy-beef cross calves. The results of the study suggest "that key health-related factors [e.g., failure of passive transfer, calf diseases (pneumonia and diarrhea)] early in life play a much larger role in calf mortality at weaning than transport duration."

Lay summary provided by the journal:

"For any dairy operation, calving is an essential requirement of the production system in which cows initiate lactation and provide the future replacements. In the US, most newborn dairy calves are moved to separate locations to be raised, which means they must be transported shortly after birth. This observational study looked at the association of transport duration with calf health, survival, and growth. The death rate of calves upon arrival was very low (0.015%) and was not affected by transport duration. However, the overall death rate by weaning (when calves stop drinking milk) was 2.49% and did vary with transport duration. The main factors linked to calf loss were diarrhea, calf immunity, transport duration, pneumonia, birth season, birth year, and gestation length. Preweaning growth rate of calves was different between female dairy calves transported 0.5 and 24 h, but not for other transport groups (8 or 17 h). While this study does not prove that transport duration directly causes changes in survival or growth, it shows that other health-related factors such as calf disease, colostrum management, calf type, birth season or year play a much larger role in calf mortality at weaning than transport duration when following well-established fit-for-transport practices."