AgResearch scientists are investigating a special type of fat that new-born lambs use to generate heat and which has a bearing on survival rates.
A research physiologist at the Grasslands campus in Palmerston North, Sue McCoard, says they've found that giving nutritional supplements to ewes during pregnancy can boost the amount of brown fat in lambs.
She says that could hold the key to whether lambs, especially twins or triplets, survive cold weather.
Dr McCoard says brown fat stores are quite high in a new-born lambs and they are burnt very quickly, so they are broken down by the lamb shortly after birth.
She says within about three days most of the stores of brown fat are gone and although they retain small amounts of brown fat through into adulthood, it's particularly important for the survival of the lamb in the first one to three days of age.
Dr McCoard says the project is also looking at the use of thermo-imaging as a non-invasive way to gauge the amount and availability of brown fat carried by each animal.
Before, the animals had to be slaughtered to measure the fat levels.