August 15, 2019
Published in Progressive Dairyman Canada, 2019
A tremendous amount of focus and attention is given to trying to reduce sickness and death occurring in the preweaning period or the first 60 days of life. However, an even more deadly period in the calf’s life occurs in the first few hours after birth.
The National Dairy Study, which was conducted in 2015, identified that many dairy farms across Canada have challenges with stillborn calves.
What is a stillborn, and how common is it in Canada?
A stillborn calf is defined as a calf that dies at birth or within the first 48 hours after calving following a gestation period of 260 days.
The National Dairy Study found approximately 5% of calves die in the first 48 hours after birth; however, as Figure 1 identifies, there is a wide spread in the number of stillborn calves on different farms, with some reporting no stillborn calves and other farms reporting more than 20% calves dying at birth or within the first 48 hours of life.
What is the cost of a stillborn calf?
Having a stillborn can be a costly event, with a reported loss of nearly $900 for each stillborn calf occurring.
Most of the cost is due to the loss of the calf; however, there are also consequences in the cow with reduced productive and reproductive performance (Figure 2). Thus, on many farms there is a tremendous opportunity.
Determining the stillbirth rate on your farm
Many on-farm software programs are capable of keeping track of stillborn calves, as is DHI, where they are able to enter it onto their software program.
However, these software programs are only as useful as the data entered into them, so before checking these programs, make sure all the calving events are correctly recorded.
How to prevent stillbirths on your farm
As 90% of stillborn calves are alive at the beginning of calving, much of this loss is preventable. The main causes for a stillborn are dystocia, or difficult calving, and lack of oxygen getting to the calf.
So improved calving management can have an impact on reducing the number of calves that die at birth or the first 48 hours. However, preventing difficult calvings from occurring could lead to the greatest reduction in stillborn calves.
There are many factors that can be influenced to improve calving events. Some of the major ones include the following:
- Movement prior to calving: Ensure the cow is calving in the designated maternity area. Calving outside the designated calving area has been shown to increase the risk of a difficult calving and stillbirths as well as a higher risk of calf disease.
If using an individual calving area, move the cow more than two days prior to calving or when the amniotic sac or feet are at the vulva, as movements at these times can lead to a shorter calving duration, reduced level of assistance and a lower risk of a difficult calving and stillbirths when compared to moving cows in stage one of parturition.
- Calving supervision: Ensuring that cows are receiving a high quality of supervision can help lead to more positive outcomes at calving. Consider using camera surveillance, providing calving management training to staff and increasing the frequency of observation of cows close to calving.
- Calving intervention: Intervening at the correct time will help improve calving outcomes in both the cow and the calf. It is recommended to apply an intervention when cows are in labour more than 70 minutes after the presentation of the amniotic sac or feet at the vulva.
However, as the onset of these signs are unknown for many calvings, monitoring progression could be used as a substitute, where progress should be seen every 30 minutes or an intervention should be applied.
- Newborn calf management: Once the calf is out of the cow, the calf needs to be assessed to determine the appropriate management that could be provided. Calves with poor muscle tone or that have difficulty breathing require assistance immediately.
When a calf is exhibiting these behaviours, ensure the nose is clear of debris to establish an airway and use either cold water in their ear or put straw into their nostril to stimulate breathing.
Finally, place the calf in sternal recumbency or in a sitting-up position to facilitate easier breathing.
Calves born from difficult calvings should also receive a pain reliever, like meloxicam, as it has been shown to improve health and vigor. They should be fed colostrum as soon as possible and placed in clean, deep-bedded straw.
Preventing difficult calvings
Many management practices occurring well before calving time can help in reducing difficult calvings. It is important to consider the following when reducing difficult calvings:
- Body condition score: Overfeeding in the last trimester will lead to larger calves being born and an excessive amount of fat being deposited in the birth canal, leading to a smaller area for the calf to pass through. To minimize this, have a target BCS of 3.50 for cows and heifers at calving.
- Size of first-time calvers: First-lactation heifers have the greatest risk of having a difficult calving, and ensuring heifers are well grown can significantly reduce the stillbirth rate. To ensure an appropriate size at calving, Holstein heifers should average 850 grams of growth per day pre-calving and have a hip height of 50 to 52 inches at breeding.
- Genetics: Selecting sires that have a good calving ease will also reduce the number of difficult calvings that occur. This is especially important to consider when breeding heifers due to their smaller pelvic size.
Stillborn calves commonly occur in the dairy industry. A large proportion of stillborn calves can be prevented through appropriate sire selection, ideal body condition score, optimizing the size of first-time calvers and proper calving management.
Work with your veterinarian and nutritionist to determine what changes would work for your farm.