Last February we discussed getting prepared for the calving season (“A Successful Calving Season Leads to More Pounds at Weaning”), by preparing the calving area, gathering equipment, knowing the stages of labor, taking care of the newborn and data collection. In this column, I would like to add more detail to the stages of labor. Not being a veterinarian, I have gathered information from varied sources and personal experience.
From the blog “Beef Cattle 101” (https://beefcattle101.wordpress.com/), Ryan Goodman nails it with his title: “5 Signs You’re About to Miss Supper.” These signs represent the stages of labor. Knowing something about them will reduce your risk of losing a calf due to inaction or acting too soon. Not in any particular order, Goodman lists these five signs, with the stage of labor in parentheses:
- You see feet (2).
- Tail twitching (1)
- Segregation from the herd (1)
- Swelling vulva (1)
- Bagging up (1)
This stage is marked by dilation of the cervix, a.k.a. “the preparation phase.” This can take up to 3 hours in a cow and up to 72 hours for a heifer. During this phase the ligaments of the pelvis and associated structures relax. The cervix, vagina and vulva all dilate, and the cervical mucous plug is released. All these changes are to facilitate the passage of the calf. Interference before this stage is completed should be avoided because dilation of the cervix will be incomplete, making it susceptible to irreparable damage.
Noticeable signs in the cow/heifer:
- Tail twitching
- Restlessness, kicking at her belly
- Stand with tail raised and back arched.
- Segregation from the herd
- Swelling of the vulva “springing”
- Expulsion of clear mucous
- Bagging up, enlarged teats
- No signs. A few cows may not show any signs until you see the water bag or feet, which is technically the start of Stage 2. As you become more experienced you will notice subtle signs, which mean a new life is on the way.
The start of the second stage of labor is signaled by the appearance of the water bag. At this stage, the fetal membranes, followed by the calf, are forced into the cervix or birth canal. When you see the water bag, note the time. Knowing how long the cow/heifer has been in this stage is crucial to determine if she needs assistance. Cows should calve within 2 hours and heifers within 1 hour of the appearance of the water bag. If progress is not made within this timeframe, she should be examined.
- Noticeable signs in the cow/heifer:
- Water bag protruding through the vulva
- Feed protruding through the vulva (though feet can move in and out initially)
- Strong and coordinated contractions
- Cow/heifer can be standing or lying on her side.
- Birth of the calf
The final stage of labor is cleaning or passing of the afterbirth. The continued contractions of the uterus expel the remaining fetal membranes. The third stage of labor lasts 1 to 8 hours. Cows not cleaning within 12 hours of birth of the calf are considered to have a retained placenta. Discuss treatment of retained placenta with your veterinarian.
The table in this article lists stages of labor and associated events. Most of us who raise beef cows work off the farm; therefore, the labor process can easily occur during the time we are at work. Knowing the signs to look for to ensure that we know where a cow is in the birthing process can mean the difference between failure or success and profit or loss.