Emma Cuttance from VetEnt Te Awamutu explains how to ensure your calves have the best start to life.
Calves are born with a poorly developed immune system, meaning they lack protection against infectious diseases. To obtain immunity until their own system is up and running, they must absorb antibodies – specifically Immunoglobulin G (IgG) – from colostrum.
Calves that fail to absorb enough IgG in their first 24 hours are considered to have Failure of Passive Transfer (FPT). This can result in increased rates of mortality and disease, and long-term reductions in animal productivity.
How prevalent is FPT?
In 2015, DairyNZ and the Sustainable Farming Fund funded a study of 4000 dairy calves from nine regions across New Zealand. The research found that on average 33 percent of all calves fail to absorb enough IgG, and the range from farm to farm is 5-80 percent. This indicates many calves are not getting enough good-quality colostrum soon after birth.
How can you prevent FPT?
Regardless of how you feed colostrum to your calves, follow these steps below to help prevent FPT.
Step 1: Test calves for FPT
Firstly, test for levels of immunity by blood sampling 12 healthy calves between 24 hours and seven days old. If the prevalence of FPT is above 20 percent then talk with your veterinarian about steps 2 and 3 below.
Step 2: Test colostrum quality
Use a Brix refractometer (available through farm supply stores) to test the colostrum you intend to feed to newborn calves. Brix readings of more than 22 percent indicate the colostrum has a suitable concentration of IgG in it. You can start by testing the pooled colostrum. If this is of poor quality, you’ll need to test individual cows as they will give different results.
Step 3: Follow some basic quality control methods
- Feed new-born calves 10-15 percent of their bodyweight (4-6L for a 40kg calf) in gold (the best quality) colostrum within 6-12 hours of birth.
- Feed newborn calves gold colostrum only from cows with a Brix reading of more than 22 percent. If you’re pooling colostrum, select only healthy cows. Be aware that pooling colostrum increases the risk of infecting calves with contagious diseases such as Johne’s.
- Use hot soapy water to clean all equipment and buckets, as this will remove colostrum fatty residues that can cause bacterial contamination.
- Store colostrum in a lidded drum or vat and stir regularly. Ideally, colostrum should be refrigerated (at 4° C).
- Quickly – get colostrum to your calves within 6-12 hours of birth.
- Quantity – give your calves 10-15 percent of their body weight in colostrum.
- Quality – feed your calves colostrum with high IgG concentration and low bacterial contamination.
This article was originally published in Inside Dairy June 2017