Jetting Principles

Effective jetting is achieved by thorough wetting through to the skin in areas most likely to be affected by Flystrike that is from the poll, over the shoulders, down the back line, over the crutch and around the pizzle.
Wetting to the skin maximises the efficacy of the pesticide giving maximum length of protection.

Volume Retained

The volume of dip chemical retained in the fleece is important in achieving maximum results.
The industry recommended dose rate is 0.5 of a litre per month of wool growth, use appropriate spray nozzles so that the important areas are covered. The number of nozzles, operating pressure and the speed of sheep through the jetter determines the volume of dip applied.

Speed Through The Jetter

Jetting should not be a race against the clock. The ideal situation is to have sheep walking through the jetter, not running or barging. Positioning the jetter at an angle to the drafting race will help regulate the flow.


We supply Davey or Onga twin impellor pumps with our jetters. Twin impellor pumps provide high pressure and high flow, Davey and Onga pumps are well suited for sheep jetting. Enough pressure at the spray nozzles is required to provide adequate wetting through to the skin. Jetting trials which were carried out in 1992 by the Trangie Agricultural Engineering Research Unit of Australia found that a pump capable of 6 litres per second (360l/min) with a nozzle pressure of 450kPa (65PSI) was required. High nozzle pressures can cause misting and will actually hurt the animal making it reluctant to pass through the jetter in the future.