Perinatal mortality (PM) — the death of calves prior to, during, or within 48 hours of birth after a normal gestation — is about 8.1 percent for U.S. dairy cows, and two to five times higher for first-calf heifers.
Researcher Peng Ji at the William H. Miner Agricultural Research Institute, Chazy, N.Y., says a team of German researchers recently found that the prolonged stage II of labor (interval from water sac appearance to complete expulsion of calf) and abnormal fetal presentation were the highest risk factors for PM. “These two factors are associated with management an hour or two before calving,” says Ji.
The three critical decisions by human handlers during this time are:
• Time to move – Moving to group or individual calving pens during stage I of labor (mucus discharge) appears to interrupt and prolong labor the most. Better to move well in advance of labor, or during stage II when calving is imminent.
• Time to give a hand – Recent research suggests the old “two feet/two hours” rule of providing physical assistance is too long, and that it is best to begin assisting cows if the calf is not expelled after 65 minutes of feet appearance or 70 minutes of water sac presence.
• Calf resuscitation – A standard operating procedure should be established for cleaning the airway of newborn calves and stimulating respiration.