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The Behavior of Cows When They Are Ready to Give Birth

Like humans, cows are pregnant for roughly nine months. Gestation ranges from 279 days to 287 days -- with 283 days the average. Cows carrying males often have longer pregnancies while cows carrying females usually deliver earlier. The age and breed of the cow also affects the length of her pregnancy.

Behavior That Indicates Labor is Beginning.
- The cow separates herself from the herd before giving birth.
  
  Labor only lasts six to 12 hours, so check the cow regularly as her due date approaches. When labor is starting she may separate herself from the rest of the herd. She may lay down and get up on a regular basis and appear restless or agitated.
Physical Signs That Indicate Labor is About to Begin.
- The udder swells prior to calving.
  
  The udder will show growth two to three weeks before labor. The teats become engorged and there is colostrum in the udder. The vulva swells and secretes mucus. Two to three days before labor, the tailhead becomes sunken or hollow.
The First Stage of Labor.
- During the first stage of labor the cervix dilates and contractions begin. The stage ends when the water bag is expelled. Stage one takes two to six hours.
The Second Stage of Labor.
- The calf is born during the second stage of labor.
  
  During the second stage of labor, contractions become stronger and more intense. The calf enters the birth canal and is delivered. Stage two takes less than two hours.
The Third Stage of Labor.
- During the third stage of labor the afterbirth is expelled. Stage three takes two to eight hours.

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