Last January the average temperature recorded across the UK was 4.1°C, for February it was 2.4°C. The lower critical temperature (LCT) for a calf under three weeks (the temperature below which a calf needs additional energy to keep warm) is between 10°C and 15°C – depending on wind speed.
This clearly shows that we should be doing something to help the animals most susceptible to cold temperatures. So, what are our options?
During the cold months it is especially important to ensure that housing is adequate. Ensuring new born calves are rapidly dried (either by the dam or by you depending on your system used) ensures that the very limited supply of brown fat calves are born with isn’t burnt off before colostrum is ingested.
The temperature that calves feel their environment is at is a mixture of the actual temperature, airspeed and humidity. It is vital to reduce damp by ensuring there is good drainage. Ventilation is key to good calf health but ensure there are no draughts at calf level (remember pre-weaned calves cannot produce the stack effect).
If calves are kept in a high ceiling building, consider building shelters using straw bales and off-cuts of wood. Finally, make sure the calf has plenty of dry, clean bedding. When a calf has nested down in straw you should not be able to see its legs.
Calf jackets help create a micro-environment for your calf, keeping it warmer and allowing it to conserve more energy, to be used for growing.
There are, however, some important things to consider when buying calf jackets:
- Firstly, is it breathable? Poor jackets are like us wearing cheap waterproofs, they don’t allow moisture to pass through and therefore they trap a layer of sweat along the calf’s back. Conversely, if your calves are outside at all, is it water resistant/ waterproof? Calves outside do not want to be stuck with a waterlogged blanket over them.
- Is it machine washable? This is really important with disease control. Ideally, the worst contamination should be removed using a hose or by soaking, the jackets can then be put in the washing machine (NB if you have a cryptosporidium problem on your farm they will need to be soaked in a licensed disinfectant before being put in the washing machine). Lesser quality jackets will shrink on washing.
- Finally, how does it attach to the calf? There are various different types of straps and fastenings. The main considerations are: adjustable straps – these should be checked, at a minimum, weekly; and types of fastenings. Velcro fastenings may seem quick and easy but they are readily clogged with dirt and easily removed by that cheeky calf with a wandering tongue. For this reason simple clips are advantageous.
We offer a range of calf jackets including cosy calf; please speak to one of the vets about the available options.
How Can We Check That Our Management Is Working?
Monitor your calves!
Hopefully they are being checked at least twice a day but simple signs of ill health include:
- Dropped ears
- Discharge (from nose or eyes)
- Refusing feed
- Coughing or scouring (diarrhoea).
Another way to ensure all these additions are working is to record weights. A quick, cheap and easy way to start is using a weigh tape to record a birth weight, four week weight and a weaning weight. This allows us to calculate a rough daily live weight gain (as mentioned above, the target is 0.8kg/day), the four-weeks of age weight allows us to see if our management is working and adjust accordingly in order to maximise our key eight-week period.
We understand that sometimes, whilst you are keen to try these things, there aren’t enough hours in the day! Scarsdale Vets is proud to have several trained veterinary techs, who in addition to coming and helping with weighing, can help with vaccinating and calf health scoring (using a recognised method for identifying pneumonia). If this is something that you are interested in, please contact the practice.