Abdominal palpation in the last two months of pregnancy. Examination of the ewe's udder during the four weeks before the start of lambing. Harnessed teasers Introducing teasers to the flock harnessed with marking crayons when the entire rams are removed will mark ewes that return to oestrus. These marked ewes should not be pregnant. However this method does not detect barren ewes which do not come into oestrus.
Crayons are available in red, green, blue and yellow.
Yellow crayons do not leave a clear mark and should not be used. Each colour is available in three degrees of hardness. The 'hot' crayons are the hardest, then 'mild' and 'cold' the softest. Crayon should leave a visible mark for at three weeks. Ewes mated in January in the Wongan Hills area require 'hot' crayons, but for the same month around Mount Barker 'mild' crayons are satisfactory.