Abstract:
1. A Merino sheep dipping experiment is described at the Bathurst Experiment Station in the coastal region, which for the greater part is a tick-infested area.
2. Ninety Merino hamels were used. Half of the plain-bodied, long loose wool type and half the wrinkly short dense woolled type. Each group was divided into three lots of 15. The first lot dipped weekly in arsenite of soda of strength 2 pounds per 100 gallons of water, the second dipped in water, the third not dipped. There were thus thirty animals for each of the treatments.
3. The aim of the experiment was to establish whether the Merino sheep could withstand and adapt itself to dipping at weekly intervals for twelve months and what effect such dipping will have on the fleece.
4. Results show that weekly dipping does not influence the condition of the sheep as reflected in body weight.
5. All sheep dipped in arsenite of soda, survived after a year's treatment, and were always free from ticks and blowfly trouble.
6. Arsenite of soda had no influence on fleece weights, fibre thickness, staple length and fibre contour.
7. As regards colour, handle and appearance the wools dipped in arsenite and in water have deteriorated to some extent. Deterioration is practically of the same degree in the two dipped groups and presumably due to the hardness of the Bathurst water and not to the arsenite of soda dip.
8. As regards monetary value, as given by Messrs. John Smith & Sons, there is as much as 1d. per pound difference between the Noil from the control and that from the dipped lots, and in the Top a difference of 2d. per pound. The latter quotation at the time of estimating (23rd November, 1931), meant a difference of approximately of 1d. per pound in the grease for a 50 per cent yielding wool, or a reduction in value of about 8 per cent.
9. There was no difference in response between the wrinkly bodied short dense woolled sheep and the plain bodied long loose woolled animals.