As another cold snap hits the UK, farms need to monitor the environment their calves are in to ensure they achieve sufficient growth and minimise the risk of any health and disease issues.  I have outlined below a number of key points regarding temperature and will follow up next month with wider environmental considerations.

Calves under 3 weeks of age have a lower critical temperature of 15⁰, below this temperature, calves divert energy that should be used for growth to just keep warm.  Do you know the temperature in your calf housing at 3am?  A thermometer that records minimum and maximum temperatures should be a standard piece of kit for anyone rearing calves to gain an understanding of the temperature variation, at all times of year to allow adjustments to be made to rearing protocols.

There are a number of ways to mitigate for low temperatures.  Firstly bedding, deep, dry straw bedding will allow a calf to nest down and protect itself to a certain degree from the cold.  Calf jackets, although initially expensive (around £20 each) can be a great investment for young calves, but make sure they are breathable and also washable at 60⁰ as they should be thoroughly cleaned and disinfected between each use.

Lastly, feeding can also be reviewed, whether as a routine change for the colder months or for just a few days if it becomes especially cold.  The advice is to feed an additional 50g of milk power or 0.33l extra whole milk per 5⁰ degree drop below 15⁰.  The important thing with any change in diet is to maintain consistency where possible, if milk powder quantity is changed on a short-term basis, it is best to feed more in total rather than increasing the concentration level of the current mix to prevent the risk of nutritional scour.  During the particularly cold weather last spring, we recommended introducing a third feed, especially for younger calves rather than just increasing the amount fed in a normal two milk feed diet.  This change in protocol was very effective, albeit resulting in a short-term increase in labour requirement but removed the risk of losing young calves that were unable to consume sufficient feed to maintain body temperature.

Small, inexpensive changes can have a massive beneficial effect to ensure calves meet their required growth rates in the first weeks of life when they are most efficient at converting their feed into growth.  The data I collected for the AHDB Calf to Calving programme highlighted that calves under growth target at weaning struggled to get back on target and more importantly, were the first to drop daily liveweight gain if they encountered an environmental or health challenge.

For more information on calf rearing, contact Andy at andydodd@fcgagric.com or your local FCG office.