Calf Health: Colostrum Management
Colostrum — the first milk produced by the cow after calving — is critical for calf survival and welfare. Colostrum provides immunoglobulins (passive immunity), growth factors, and nutrients that calves cannot obtain any other way, and the window for absorption is brief. Failure of passive transfer (FPT) leads to significantly higher morbidity and mortality in the critical neonatal period.
The Importance of Timing
Calves are born without functional immunity — the bovine placenta does not allow transfer of maternal antibodies. The gut can absorb immunoglobulins (IgG) through specialised enterocytes, but this ability declines rapidly after birth and is largely lost by 24 hours. Colostrum must be provided within the first 2 hours of life for optimal absorption — the earlier the better.
Calves that receive adequate colostrum rapidly have dramatically better survival rates, lower disease incidence (particularly neonatal calf diarrhoea and pneumonia), and better lifetime performance than calves with FPT.
Quality and Quantity
Not all colostrum is equal. IgG concentration varies widely between cows — older cows typically produce higher-quality colostrum; cows vaccinated before calving transfer more pathogen-specific antibodies; colostrum from cows with premature colostrum leakage before calving may be diluted. A refractometer (Brix measurement) or colostrometer assesses quality — targeting Brix >22% (equivalent to >50 g/L IgG).
Recommended quantity is a minimum of 10% of birthweight in the first 24 hours, with the first feeding of at least 3 litres (or 10% of bodyweight) within 2 hours. For a 40 kg calf this means at least 4 litres total in the first day, with the first 3+ litres given immediately.
Tube Feeding When Needed
Weak calves, those born in poor weather, those from prolonged calvings, or those not nursing adequately within 1-2 hours should be tube-fed. Oesophageal tube feeding is a welfare intervention — it ensures adequate colostrum delivery when the calf cannot achieve this naturally. Stockpeople should be trained in correct technique to avoid tracheal delivery.
Colostrum Management Protocols
Colostrum banking (freezing excess high-quality first colostrum) allows provision when cow colostrum is inadequate. Pooling colostrum should be avoided — it dilutes quality and can spread disease. Commercial colostrum replacers are available for emergency use but are inferior to good-quality fresh or frozen maternal colostrum.