- Calving chains/handles and calf puller
- Warm water
- Palpation sleeves/gloves
- Obstetrical lubricant and surgical soap
Normal Stages of Calving:
Stage 1: Progressive relaxation and dilation of the cervix and initiation of uterine contractions moving the calf into the birth canal. During this period is when the cow/heifer may seem uncomfortable, become isolated, vaginal discharge may be present, and the waterbag (chorioallantois) may be seen outside the vagina. Mature cows may show few signs compared to heifers. The first stage of calving lasts on average 6 hours but can last up to 24 hours.
Stage 2: Occurs when the waterbag breaks and the dam begins to have strong uterine contractions which forces the calf into the birth canal. The dam may get up and down repeatedly but will usually deliver the calf laying on her side. This stage lasts 2-4 hours in mature cows and slightly longer in heifers and ends with expulsion of the calf. A delay in this stage indicates that the cow may have dystocia. However, it is important not to disrupt the dam during this time as she may delay progress if overly disturbed.
Stage 3: This is the last stage of calving and is characterized by the dam passing her placenta. In many cases it may take only a few minutes or hours but it is not abnormal for some animals to take up to 18 hours before passing the placenta. After 24hours without passing the placenta qualifies as a “Retained Placenta”
When something isn’t going right…
A dystocia is defined as any delay of the first or second stage of labor and can be caused by factors associated with either the dam or the calf.
Dam factors causing dystocia include uterine inertia and abnormalities of the birth canal. Uterine inertia is when the uterus no longer contracts and expulsion of the fetus does not occur. This can be due to a lack of uterine contractions due to an abnormality of the uterine muscles (primary uterine inertia) or due to exhaustion of uterine muscles due to an impediment of fetal expulsion (secondary uterine inertia). In animals with primary uterine inertia the cervix is dilated and the fetus not yet in the birth canal. With secondary uterine inertia there is usually malposition, malpresentation, or large calf preventing expulsion of the fetus.
Calf causes of dystocia are various but include abnormal position, posture, or presentation, fetal monsters, and simply an oversized calf. The last two causes are obvious causes of dystocia. It is the abnormal position, presentation, or posture of a calf that can often be difficult to correct. The actual presentations that producers sometimes see include: leg back (either forward or backward presentation), head back (can sometimes be an indicator of fetal oversize), breech (tail and hindquarters with both back legs down), and various combinations (especially if twins are present!)
When to assist calving:
- If the water bag is visible for 2 hours and the cow is not trying.
- If the cow has been trying for over 30 minutes and made no progress.
- If the cow has quit trying for more than 20 minutes after a period of progress.
- If the cow or calf is showing signs of stress or a swollen tongue or severe bleeding from the rectum of the cow.
- If it appears that the delivery is abnormal (backwards/leg back).
With these guidelines in mind I hope to not make you feel rushed when you see a cow calving. The process normally takes time and early intervention can be stressful on the cow and calf and potentially disrupt the cow and calf bond.
Before the vaginal exam:
- Ensure animal is properly restrained whether standing or laying down and all people are in a safe position.
- The vulva and perineum (area around the vulva) should be cleaned with surgical soap (betadine or hibitaine scrub) and water.
- There may be frequent recontamination of the vulva as the cow strains and defecates. Keep cleaning the area so you don’t drag manure into the vagina.
- Shoulder length palpation sleeves are ideal for vaginal exam to reduce risk of becoming contaminated with fetal fluids that may contain material infectious to humans.
- Generous amounts of lubrication using Obstetrical lubricants can be extremely helpful.(Do Not use J-Lube!)
The Vaginal Exam:
- Cervix open/closed
- Cervix dilation
- “Water bag” fetal membranes open
- Presence of feet
- Uterine torsion
Is it a front leg or a back leg?
Generally speaking if the dewclaws are down it’s a front leg and if they are up it’s a back leg. However, that’s only true in the calf coming in normal forward or the typical backward presentation. This can easily be complicated with if a front and a back leg are coming or if twins are present. So a more reliable way to tell front from back leg is this:
The first two joints on the front let (fetlock and carpus see image) will bend in the same direction. The first two joints on the back leg (fetlock and hock see image) will bend in the opposite direction.
From here one can get a general idea of the position of the calf and hence how to potentially correct the position allowing for normal extraction of the calf.
Requirements Before Pulling:
- Two feet and head engaged in birth canal/pelvis
- Properly placed calving chains (double loop above/below fetlock)
- Two feet and hips engaged in birth canal/pelvis
- Properly placed calving chains (double loop above/below fetlock)
NEVER PULL A CALF IF THERE IS A LEG BACK OR HEAD BACK!!!
NEVER PULL A CALF IF CERVIX IS NOT DILATED ENOUGH!!!
With the calf coming front feet forward it is important to assess if the calf is able to be pulled. This requires pulling on the legs of the calf. Proper chain placement is critical (see diagram) as an improperly placed chain can damage/break the calf’s leg. If only the head is present in the birth canal then the shoulders should be delivered by pulling on one leg and then the next (see diagram) to bring them into the birth canal one at a time. If you are unable to get the head or both shoulders into the birth canal a caesarean section may be required. However, after both shoulders and the head are in the pelvis equal traction on both legs can be applied. The calf should be pulled in a slightly downward motion to accommodate for the curve of the pelvis (do not pull straight out and horizontal with the ground).
The next obstacles is the hips. Occasionally a calf can become “hip locked” or the calves hips are stuck in the birth canal. Fortunately this can be easily fixed by rotating the calf as the cows pelvis is oval (see image). It can take up to a 180˚ turn of the chest to get the hips to rotate enough to allow for extraction of the calf.
A calf that is presented backwards can not only be difficult to deliver but has many more complications. Backward calves umbilical cords are more likely to prematurely rupture or have pressure on their umbilical cord increasing the risk of a calf running out of oxygen (hypoxia) or umbilical conditions. These calves may have to have their hips rotated so they fit through the oval birth canal of the cow (see above diagram). This can be done by crossing the legs before pulling the calf. In the backward presentation a vaginal delivery is likely if the hocks can be exposed outside of the vulva. If the hocks can’t be exposed then a caesarean section is likely needed. Once the hips are presented a vaginal delivery is generally easy. When pulling a backwards calf the calf should be pulled almost straight out from the cow. Hard pulls in the posterior presentation could result in fractured ribs or puncture of the lungs if care is not taken.
These include a leg back or head back. Both of these conditions require correction before the calf can be delivered. The leg back may require repulsion (pushing the calf back into the uterus) to allow enough room for the leg position to be corrected (this can be difficult with the cow straining and may require veterinary attention). With a head back this may sometimes be an indicator that the calf is too big to enter the birth canal. If correcting a head back it is important to never pull on the tongue, mouth, or jaw of a calf as it may cause trauma, bleeding, and even jaw fractures.
However if difficulty is reached, the calf is too big, can’t correct the position, or the cow is straining too hard to help correct the position then likely veterinary attention is needed.
Fetal Oversize: Calf is Too Big
- Often find a head back
- Can’t engage head and both legs into birth canal
- Can’t get both shoulders into birth canal
- Can’t get legs out to level of carpus/hand breadth of fetlock past vulva
- Can’t engage hips into pelvis
- Can’t get legs out to level of the hock
When to call the vet:
- Failure to dilate
- Head back (Can`t get head)
- Breech (Can`t get legs up)
- Uterine torsion
- Fetal Oversize (Calf is too big to pull)
- Feel guts or unrecognizable calf
- Any other situation you feel you need help
Reviving the calf:
Once the calf is out and is alive it should be stimulated to help encourage breathing. This can be done be rubbing the calf vigorously with a towel and sliding a piece of straw into the nostril of the calf.
Assisted Calving Flow Chart: