Management of calves in commercial dairy farms in Mecklenburg-Western Pomerania, Germany and its impact on calf mortality and prevalence of rotavirus and infections in pre-weaned calves.

In a cross-sectional study, impact of management in dairy farms on calf mortality rates and prevalence of rotavirus and in feces of calves was investigated. Sixty-two commercial dairy herds in Mecklenburg-Western Pomerania, Germany, were stratified selected in 2019. We performed in-person interviews and fecal specimens in samples of all-female calves of age 7 up to 21 days. Management data were documented on farm level. A Multiscreen Ag-ELISA was performed to determine rotavirus and . Associations between two calf mortality rates, detection of and rotavirus, and predictors were examined with GLM models. In farms with routine vaccination against respiratory diseases, 31-days mortality rate was 4.2% +/-1.26 compared to 7.6% +/-0.97 ( = 0.040) on non-vaccinating farms. Six-months mortality was lower in farms that continued feeding milk to calves during periods of diarrhea compared to farms that did not (6.9% +/-0.8 vs. 12.4% +/-2.3). In case of a routine shifting of calves from the calving box into calf boxes less was detected compared to an individual moving of calves (33.3% +/-2.6 vs. 19.6% +/-5.3;  = 0.024). Our model confirms a positive association between occurrence of aqueous feces and frequency of detection of (45.4% +/-23.6 vs. 21.4% +/-18.7;  < 0.001). Frequency of detection of rotavirus was lower in farms that reported a defined amount of applicated colostrum per calf than in farms that presented a range of colostrum instead of a defined amount. This study indicates the potential for mitigation of risk factors for mortality in calves.