Persistent Effects of Neonatal Diarrhea on Holstein Dairy Cow Lactation Performance through Multiple Parities

Lay Summary Diarrhea in calves is one of the key factors affecting the lactation performance of dairy cows. This study offers brand new insights into the short-term and long-term effects of diarrhea in calves on subsequent lactation performance in Holstein cows. The observed diarrhea in calves impaired growth and reduced milk production, milk fat percentage and milk protein percentage during lactation. Meanwhile, the impact of diarrhea in calves on lactation efficiency was observed in the short term and expanded over time. Furthermore, milk production can serve as a mediating effect of calf diarrhea on milk fat percentage. These findings advocate for the need for early-life interventions to mitigate lactation losses in high-parity herds.