Though there are broad similarities in all ranching operations, we all know that every ranch, every herd, and every enterprise is unique and different. Some ranches sprawl over miles and miles and are stocked with thousands of cattle; some operations consist of a handful of cows on a small patch of ground. Regardless of size, though, the saleable commodity for cow-calf operators is the calf crop. Perhaps the most critical phase of production is the period immediately surrounding calving. Death loss at calving can quickly destroy all the best laid plans of profitability on the ranch. Dead calves don’t sell, so regardless of your goals, vision and management practices, if you’re not on top of your game at calving time, your operation is unlikely to thrive – or even survive.

Close observation as calving approaches allows the producer to quickly intervene when calving difficulty – dystocia – occurs. Simple interventions at the correct time can often ease difficult labor and save calves. Delayed intervention markedly increases mortality. Closely observing the cow herd as calving time approaches allows the producer to accurately anticipate the onset of birth, or parturition.

Cows show typical signs when labor is approaching and when parturition is imminent. Some signs of approaching parturition are udder development and the relaxation and swelling of the vulva. As these changes occur, the cow is closely approaching calving. There is no surefire sign that labor will begin at a certain time, however, and every animal is different. Some will calve within a day or two of the first signs, but most will hold off for a week or more. Younger cattle, particular first-calf heifers, may show udder development as many as three weeks before parturition.

In general, udder filling begins around two weeks prior to birth, followed more or less closely by vulvar swelling. Often the cervical mucus plug is lost around this time, producing a thick mucous material hanging from the vulva. This is often noted pooling behind the cow when she is lying down. Loss of the cervical plug is rarely a sign of imminent calving, rather it can be seen weeks before parturition.

Signs of closely impending birth – usually occurring within 24 hours of calving -- include relaxation of the pelvic ligaments and strutting of the teats, both signs which are fairly dependable for the producer who closely observes the cow herd several times a day during the calving season. Relaxation of the ligaments can be seen very clearly in thin or moderate body condition cows and can be a clue of parturition within the next 12 - 24 hours.

Behavioral changes can also indicate approaching birth, though such changes are not sure signs. Some cows will self-isolate from the rest of the herd, or will become indifferent to feed, up to 12 hours befor the onset of parturition. Others, however, may not exhibit behavioral changes until the birthing process actually begins.

Close observation allows the rancher to get a good, accurate sense of the birthing process for individual cows in the herd. This is important, for it allows the producer to gauge and get a solid sense for the speed of the process in individual animals. Even expert cattlemen and veterinarians can rarely predict calving time from these signs alone.

Calving time can mean long hours and extra work, but spending that time and effort at calving time will almost always pay the dividend of lower death loss and more live calves sent to market.