The application of affordable equipment and common sense is all that’s needed to properly test the suitability of calf housing, experts have said.
Data logger information collected in September and January on one of AHDB Dairy’s 13 Calf 2 Calving farms, showed that even in winter, calf hutches saw peaks and troughs in temperature both within and between days.
Faster growth rates and better subsequent lifetime production could be improved by monitoring and managing three environmental factors; temperature, air speed and humidity, the data suggested.
According to AHDB Dairy technical manager David Ball costs can vary hugely but for around £25-£30 a farm can kit itself. He said: “A USB data logger to monitor temperature and relative humidity over time will cost about £65.”
However, it’s possible to get hold of a max/min thermometer and a hygrometer from the internet or a local garden centre for much less.
“An effective vane anemometer can cost from £7 upwards from the internet,” said Mr Ball, adding that a hot wire anemometer capable of measuring air speeds as low as 0.1 m/s would cost more, £150-plus. “The cheaper option is probably sufficient to measure air speeds in calf sheds,” he said.
The fresh insights from data loggers on the AHDB Calf 2 Calving farm showed calf hutch temperatures ranged from day time temperatures of 25C-45C and night time temperatures of 0C-5C in September and January respectively.
Mr Ball explained: “If temperatures fall below 15C, some of the energy from feed will need to be used by the calf to keep warm. 25C is also the calf’s upper critical limit – above this they need more energy to keep cool.”
- Air speed: 0.2m/second squared = less than walking speed
- Humidity: Closer to 50% the better. At 75% bacteria aren’t being desiccated
- Temperature: 15C-25C
He added: “Relative humidity levels of over 70% will result in little or no pathogen desiccation (drying). A relative humidity of below 50% will inhibit pathogen growth.”
Monitoring your shed
Independent animal health and housing expert Jamie Robertson, research fellow at the University of Aberdeen, warned that the UK’s wet environment made controlling moisture quite challenging.
He told Farmers Weekly that farmers could use their common sense and keep bedding dry, check floors were dry and strive to minimise the entry of moisture into buildings.
Mr Robertson suggested using smoke pellets to highlight stale air pockets and show where stale air could leave buildings.
Cost of equipment: A rough guide
- Temperature: Min/Max thermometer: £10-£15
- Air speed and ventilation: Smoke Bombs: £4-£5
- Air speed: Anemometer: £7
- Humidity: Hygrometer: £10-£15
- Monitoring: Take readings around the building, by doors and at calf level.