The first colostrum feed is critical to a calf’s short and long term health. This is due mostly to the fantastic infection fighting antibodies found in this first milk. The high nutritional content is also important to kick start a calf’s energy and growth requirements. Unlike most other animals, calves are born with no antibodies, which is risky business because antibodies are essential for protecting the animal from infections. The calf is constantly bombarded with new bugs challenging the calf’s immune system.
Very cleverly, antibodies are concentrated in the colostrum so when the calf suckles this liquid gold the calf can absorb the antibodies from its gut into the blood stream where they wait to attack pathogens and protect the calf. BUT there is a catch, the calf can only absorb these crucial antibodies in the first few hours after birth. After this it is game over, the ship has sailed, opportunity gone. A calf which missed the antibody boat has a far greater chance of getting sick or dying, and also has reduced reproductive and productive success as an adult cow. Colostrum management = lifetime consequences.
Yes calves do, after a few weeks, make their own antibodies but they are left exposed until then and the development of antibodies is often too slow for an effective response, meaning the calf succumbs to infection and disease. Whereas the colostral antibodies are ready to defend immediately.
How to achieve the best antibody absorption for the best health of your calves and future herd.
Colostrum management = the 3 Q’s
All of these three factors are important for successful colostral antibody transfer.
Absorption of the antibodies declines rapidly after birth. Here is a scary graph representing how quickly absorption declines:
As you can see you have a very narrow window of opportunity where the calf can absorb these antibodies. The first couple of hours = great! At 6 hours post birth = OK if the other Q’s are on point. At 12 hours = you are battling and at 24 hours the doors are shut.
Minimum 10% of the calf’s bodyweight in the first 6 hours. For example, a 40kg calf requires 4litres in the first 4hours for maximum benefit, you would normally split this into two feeds. Followed by another 2litres within 12hours. A lot right?! The earlier the better for antibody absorption success. Looking at the graph, if you wait until after 12 hours, that calf will require around 15litres of the same colostrum to supply the right amount of antibodies and this is clearly not practical or possible.
Another way of looking at it: the goal is to feed 100 to 150g of IgG as soon as possible after birth.
Quality refers mostly to the concentration of antibodies in the colostrum (over 50g/l IgG OR over 22% on the Brix test) and also contamination level. High quality colostrum is often referred to as ‘gold’ colostrum. These are the main factors affecting colostrum quality.
– Time from calving – antibody concentration reduces with every hour from calving, even if the cow has not been milked, her quality will be much lower 12 hours after calving than 2 hours after. As much as we wish this wasn’t true, it is, and may be the most important factor. Fresh is best!
– Volume – a high producing cow will typically have a lower colostrum quality than a lower volume cow. This can be variable.
– Leaking udders – poor quality in cows which have leaked milk prior to calving, similarly with cows milked prior to calving.
– Cow health – a sick cow has poorer quality colostrum e.g. mastitis, .
– Storage – fresh is best, there are a range of different storage methods, none as good a fresh colostrum but some are better than others. Refrigeration will maintain antibody levels and prevent bacterial growth for 24hours, beyond that freezing will adequately preserve colostrum quality for 12months.
– Vaccination – vaccinated cows will have higher levels of the associated antibodies, this is the basis of scour vaccinations – vaccinate the cow then feed the antibodies to the calves.
– Contamination – bacterial load will negatively affect the ability of your calf to absorb these precious antibodies. Be scrupulous with hygiene, harvesting methods and storage of colostrum.
BUT, there is a large amount of variation. Cows which fit the high quality criteria from above may still have poor quality colostrum. Practically what does this mean? Only target the freshest colostrum from a freshly calved, healthy, non-leaking cow for a calf’s critical first feed, and ideally test the quality with a refractometer before feeding. Testing takes only a few seconds. Over 22% brix reading is considered good concentration of antibodies. Colostrum below this should be used for 2nd and 3rd day feeding.
Cleanliness is also a very important component of quality. The longer colostrum sits around and the less clean your equipment, the more bacterial growth and the larger the bacterial challenge for the calf. Careful storage will reduce bacterial load and still maintain antibody levels for a certain period of time. Many farms also need to consider potential transfer of diseases such as Johnes therefore it is recommended to avoid pooling this first colostrum. Always be clean with equipment. A higher pathogen load will occur with unclean feeders. Always wash your feeders adequately and have separate feeders for sick calves and new-borns.
If that isn’t enough to consider, cold calves or ambient temperatures under 10 degrees celcius result in a slower antibody absorption rate.
Putting extra effort into colostrum management is well worth it for the extra benefits for your herd. You have one opportunity for each calf to get it right and the benefits are life-long! Ideally calves would naturally source enough from their mother however this scenario consistently shows a very low success of antibody transfer, so a more hands on approach is much more successful. Depending on your farming system, this normally means changing just a few steps at a time to be manageable. This is something your vet can help you with, by gathering all the information on your system and seeing where the most effective and practical improvements can be made.
You may have come across these abbreviations or terms relating to calves and colostrum:
PT = passive transfer. This means antibodies transferred to the calf i.e. successfully absorbed from quality colostrum.
FPT = failure of passive transfer. Transfer failed, calf low on antibodies due to either poor quality, low quantity or not quickly. Simple bloods tests will indicate transfer level.
Gold Colostrum = high quality or high antibody colostrum (over 50g/l IgG or 22% Brix) so suitable for newborns.
IgG = Immunoglobulins, otherwise referred to as Antibodies, a critical part of the immune defense.