The Importance of Colostrum Management during this Calving Season

Anne O’ Malley, Teagasc Advisory Ballina

The first milk produced after calving, colostrum, is highly nutrient-rich, provides the new born with both nutritional and immune benefits, and shapes the gut microbes. Colostrum and stable gut microbiota are important in early life ruminant development and impact the overall health of the animal. Colostrum contains immunoglobulins or antibodies necessary to protect the calf from disease and getting enough antibodies from colostrum immediately after birth, also known as colostrum-derived passive immunity, is central to the health, performance and welfare of calves. Bovine placenta prevents the transfer of antibodies from the mother to calf while the calf is in the womb. Calves are born with very poorly developed immune systems and the calf depends on the successful passive transfer of maternal antibodies from colostrum in order to defend itself against bacteria and viruses until its own active immunity begins to work, at about 3 to 4 weeks of age.

The calf is susceptible to infection as soon as it enters the birth canal, just prior to calving. Factors that impinge on the duration between birth and the first suckling will negatively impact on calf passive immunity and a key factor is difficult or abnormal calving. The antibodies in colostrum must get into the calf’s blood via absorption from the small intestine. It is vital that sufficient colostrum is consumed as soon as possible after birth because the ability of the calf to absorb antibodies starts to decline rapidly after 2 hours and ceases around 24 hours after birth. The earlier a calf suckles or is fed, the greater the level of immunoglobulin absorption.

Beef calves should suckle the cow until they are full as soon as possible after birth. It is recommended that beef calves should stand and suckle within 2 hours of calving; if not, the dam should be restrained and the calf should be assisted. If the calf is unable or unwilling to suckle, the cow should be milked out by hand and the calf fed colostrum with a bottle or a stomach tube. This may be necessary for weak calves, difficult births or where there is a poor calf cow bond. Research has shown that feeding the suckler calf 5% of its birth weight (e.g. ~2 litres of colostrum for a 40 kg calf), within one hour or so of birth, with subsequent suckling of the dam 6 to 8 hours later, ensures adequate passive immunity.

On dairy farms calves are removed from their mother’s immediately after birth and fed 3 litres of colostrum. If on-farm biosecurity and animal health and welfare measures are followed this will minimise the risk of infection on farm and the calf is less likely to suffer from failure of passive transfer. Ensure all feeding equipment used to feed colostrum is thoroughly cleaned before and after use as bacterial contamination can reduce the absorption of antibodies.

Colostrum quality can be tested using a Brix Refractometer (see Figure 1). Only colostrum with a brix value greater than 22% should be used in first feed, equivalent to a concentration of 50mg/ml of antibodies which is the threshold to ensure that calves acquire immunity passively.  Consult your vet and advisor in relation to colostrum management practice on your farm. Calves under 14 days old can be blood tested to check for failure of passive transfer. Samples can be tested in the local Department of Agriculture’s Regional Veterinary laboratory.

The calving season is a busy but rewarding time on farm but we must also take care of our own welfare and safety at this time. The natural instinct of all animal species is to protect their new born so this is a very high risk time. You must assess risk on your own farm put actions in place to minimise risk and this is where your HSA Farm Risk Assessment Document comes into action.