New-born calves are reliant on colostrum until the immune system develops in the first couple of months of life. Colostrum provides antibodies crucial for protection against conditions such as scour and pneumonia. Ensuring calves receive adequate colostrum is challenging. Up to 50 percent of calves do not receive enough and only 30 percent have sufficient levels of colostral immunity1.
The ‘5Qs’ – Quantity, Quality, Quickly, sQueaky clean and Quantify – are key to ensure that youngstock get the best start in life.
Give the first colostrum feed of four litres, or 10 percent of bodyweight, within four hours of birth, followed by a further two litres within 12 hours of birth. A calf requires approximately 20 minutes of continuous suckling to consume enough colostrum. If a calf is not receiving adequate colostrum try feeding the calf using a nipple feeder or stomach tube.
Good quality colostrum contains at least 50 g/L of IgG antibodies. Colostrum quality varies enormously between cows, so test quality every time with a colostrometer or BRIX refractometer.
Colostrum quality decreases 3.7 pecent every hour after birth and a calf’s ability to absorb antibodies directly into its bloodstream only lasts a few hours so colostrum must be harvested quickly, and the first feed given within the four hours of birth.
Good hygiene is essential when harvesting colostrum, either to give to a calf or store for later use as it is an excellent medium for bacterial growth. At room temperature bacteria numbers can double every 20 minutes.
If colostrum becomes contaminated, a calf’s uptake of antibodies falls and can lead to sickness such as septicaemia or diarrhoea.
Fresh colostrum at room temperature should be used within one hour or within three hours if stored in a fridge. Clean, good quality colostrum can be frozen and used within 12 months. Before use, bring colostrum up to 35-40°C in a warm water bath. Never use a microwave or boiling water.
Using frozen colostrum is appropriate when a cow is producing low quality colostrum, is down or has died after giving birth. Raw colostrum from different cows should not be pooled as this lowers overall quality and increases the risk of transmitting Johne’s disease.
Reviewing colostrum management on farm is important to make sure calves are receiving the benefit of good quality colostrum. A colostrum protocol should evaluate colostrum quality and a calf’s immune status.
Step 1 – Measurement of colostrum quality: Colostrum quality is measured by testing its specific gravity using a colostrometer or BRIX refractometer. Good quality colostrum has a specific gravity > 1.050 (> 50 g/L of IgG antibodies) or a BRIX measurement of ≥ 22.
Step 2 – Evaluation of calf immunity: A calf’s immune status is measured by the total solids in serum (STS), using a hand-held refractometer, from blood samples collected from calves aged 24 hours to 7 days. This test evaluates the transfer of antibodies from cow to calf through colostrum. STS should be 6-6.5 g/dL, with at least 85% of calves above 5.2 g/dL.
1. All-Island Animal Diseases Surveillance Report for 2012.