Restricted dietary protein in pregnant beef cows: I. The effect on length of gestation and calfhood mortality

Beef cows fed 0.37 Kg crude protein/day during the last four months of pregnancy had significantly shortened gestation (274 days vs. 282 days) and decreased weight gain (25 Kg vs. 66 Kg) compared to control cows fed 0.96 Kg crude protein/day. Calf mortality in the low protein group was associated with either dystocia (3 calves) or prematurity (2 calves). There were no deaths among control calves. It is suggested that protein malnutrition in late pregnancy may be a contributing factor to neonatal mortality among beef calves.