As we head into the colder months, it pays to remember that livestock can experience cold stress and hypothermia that can cause death if not managed and treated.
Hypothermia means “low body temperature” – anything that increases heat loss or decreases heat production can predispose livestock to dangerously low body temperatures.
What increases risk?
Animal factors:
- low body condition: less fat = lower cold tolerance
- fleece/coat thickness: animals in full wool are considerably more buffered from the cold than a newly shorn animal
- newborn animals: particularly vulnerable as they only have a limited energy/fat reserve which can be depleted fast in cold weather events
- lambing ewes and calving cows
- sick animals.
Weather and external factors:
- wind-chill: can DOUBLE heat loss
- rain/mud
- weather systems/cold fronts with sudden drops in temperature
- nutrition and roughage access: well fed animals will produce more heat via fermentation in the rumen, whilst also being more likely to have a healthy fat cover.
What can you do to protect your animals?
- Weather event vigilance – particularly after management activities that increase risk such as shearing
- Provide shelter from wind (preferably also rain) for the most susceptible stock. This may mean housing them for 24 to 48 hours under a shearing shed (whilst also providing feed and water). Lambing and off shears paddocks should be small and well protected from cold winds using wind breaks.
- Increase nutrition and roughage: cold temperatures increase energy requirements and thus the amount of feed required for animals to maintain their body weight. After shearing, sheep need a 40% increase in feed above maintenance to cope with cold stress – use weather alerts to supply this increase before the onset of the cold event. Feeding rations in the late afternoon can help increase heat production via rumination throughout the night.
Clinical signs and Treatment
Signs to look out for include shallow breathing, shivering, huddling together and seeking shelter – at this point, efforts should be made to increase access to shelter and feed immediately.
Failure to do so could result in progression to hypothermia – where animals become lethargic, lie down, gums will turn pale to white and extremities will feel cold, before becoming moribund. ALWAYS deal with animals that are mobile first, as these have the greatest chance of survival.
Move affected animals to a warm/protected area with plenty of feed. Young lambs and calves can be provided warm water via teat to increase core body temperature. If dealing with small numbers – an appropriately sized garbage bag can be used as a coat, whilst more intensive treatment may be provided by your local private veterinarian.
Get up to date weather forecasts and alerts at:
New South Wales Warnings Summary (bom.gov.au).
For more information contact your Local Land Services District Vet on 1300 795 299.