The incidence rate of SM was higher in the NRCS group (129 cases
per 1000 animal-days at risk) than in the RCS group (81 cases per
1000 animal-days at risk).
In this study, cows which did not suckle their calves after milking were 1.59 (1.20–2.10) times more likely to develop SM than cows that did suckle.
The overall prevalence of CM per cow was higher in the NRCS
group (5.8%) than in the RCS group (1.3%), while at the quarter level
it was 1.51% and 0.26% for the NRCS and RCS groups, respectively.
The incidence rate of CM for the NRCS and RCS groups was 53 cases per 10,000 animal-days at risk, and eight cases per
10,000 animal-days at risk, respectively.
Cows that did not suckle their calves after milking were 6.59 (3.15–13.93) times more likely to develop CM than cows which did suckle.