Cows go into estrus for four to 30 hours, which is indicated by swelling and redness of the vulva and general restlessness. During this time they are ridden by other cattle, both male and female. The full estrous cycle lasts between 14 and 24 days. Ovulation occurs approximately 12 hours after estrus ends. Gestation lasts between 240 and 330 days.
The actual birth should take less than two hours, and the placenta should follow two to six hours after the birth. Calves are generally born feet first with their heads between their forelegs. They receive their immunity from colostrum, which is a milky white fluid that appears after giving birth but before true breast milk appears. The Northern Virginia Community College's veterinary department advises feeding newborn calves at least 4 pounds of colostrum within an hour of birth to improve chances of survival. Cows are primarily bred for livestock purposes, focusing on weight gain to increase profits at slaughter. They are herd animals that establish a hierarchy that becomes evident during feeding and watering times. They communicate through body language, pheromones and vocalizations. Bulls display outward aggression by pawing at the ground with a hoof and charging. This behavior has also been witnessed in cows protecting their calves. Cows also kick with their hind legs.