Good colostrum management is the single biggest contributor to calf health and survival. Benefits include:
- Decrease in disease and treatments, particularly scours but also navel and joint ill
- Decrease death rates in calves
- Increased growth rates and feed efficiency
- Decrease time to get in calf
- Increased milk production for the 1st and 2nd lactation
- Decreased likelihood of being culled in 1st season
Colostrum management can be summed up by the three Qs – Quickly, Quality, Quantity.
- Calves require antibodies from colostrum to provide immunity in their first part of life. They absorb antibodies from colostrum best within the first 4-6 hours, ideally within 2 hours. The rate of absorption then declines and the calfs gut no longer absorbs antibodies after 24 hours.
- Cow’s colostrum has the greatest antibody level at birth (22% BRIX). Levels decline rapidly, 33% over the next 14 hours reaching as low as 50% at the second milking (12% BRIX). The sooner after birth colostrum is collected the higher the antibody level.
- Levels of antibody can decline in the udder and in the bucket after collection so its important to feed it soon after it is harvested.
- A high rate of calves left in the paddock to suckle fail to get enough antibody. Factors include time to rise and feed, cold temperatures, health of the dam and mothering ability. Calves should be on their feet quickly and those sitting down longer than 2 hours stay colder, have poorer antibody absorption and greater risk of illness. Best results are seen when calves are collected regularly (twice daily minimum) and bottle or tube fed colostrum as soon as possible.
- It is recommended to feed >22% BRIX colostrum. BRIX refractometers are a quick, easy to use hand held tool that can be used on farm to estimate the antibody level. Simply apply a drop of milk to the screen and measure the level via the eye piece. BRIX levels of 22% or greater indicate adequate quality colostrum. In a recent NZ study only 10% of samples were above 22% BRIX.
- Colostrum antibody levels can vary greatly between cows and not all cows make suitable colostrum. Factors such as genetics, age and length of dry period play a role.
- Jerseys produce the highest antibody levels followed by Aryshires then Fresians.
- Excessively short dry periods result in lower antibody levels.
- Cows dry for 40 days versus 60 days produce 2.2 kg less colostrum
- High bacterial levels in colostrum can inhibit antibody absorption in the calf’s gut. Colostrum is often a soup of bacteria. A recent NZ study showed a vast majority of farms fed colostrum to newborns that had excessive bacterial levels.
Strategies to reduce bacterial contamination include:
- Ensuring buckets, calf feeders and colostrum storage containers are clean and sanitised. A cover is recommended to keep out flies and rodents.
- Use of a preservative to inhibit bacterial growth. Potassium sorbate has been shown to significantly reduce bacterial growth and outperform other colostrum keepers.
- Refrigeration of colostrum. At certain times in the season it can be hard to come by enough adequate colostrum. Colostrum can be frozen for up to a year and used when decent colostrum supply is low.
- Pasteurisation of colostrum. This has been used more so overseas to lower levels of bacteria.
- Avoid feeding colostrum from known or suspected Johnes positive cows.
- Pooling colostrum from the cows first milking with second, third and subsequent milkings dilutes antibody level. This is insufficient for new born calves.
- Ensuring cows are vaccinated 3-6 weeks prior to calving boosts antibody levels in colostrum. This protects against diseases such as rotavirus, salmonella, coronavirus and E coli.
- Quantity depends on quality. Calves need to be fed larger volumes of lower quality colostrum in order to achieve adequate antibody absorption.
- The recommended volume within their first 12 hours of life is 10% of their bodyweight. This is 3-4L depending on the size of the calf. Note: If tube feeding a maximum of 2L per feed.
- Antibodies are not the only positive component of colostrum. Colostrum also contributes to gastrointestinal development and temperature management in the calf plus has antimicrobial effects. Feeding colostrum after the gut closes at 24 hours still has positive effects such as less treatment for illness, respiratory disease and scouring.
If you are wondering how you are doing on the scale of things we can assess how well your calves are doing using serum samples. Give us a call if you’d like some help.