Lambs should be marked between the ages of two and 12 weeks, with the youngest animal in the mob being at least 24 hours old so that a maternal bond can form. If lambing extends for more than six weeks, consider having two mulesing/marking sessions.
There are registered pain relief options that producers can use at lamb marking, including pain relief for tail docking and castration. Animals older than six months of age require anaesthetic for tail docking and mulesing.
Tail docking and castration
Castration should be performed on lambs as early as management practices will allow, preferably before 12 weeks of age. Animals older than six months require anaesthetic.
Acceptable methods of castration without anaesthesia include:
- Cutting. The lambs should be properly restrained and the knife must be kept clean and sharp.
- Rubber rings applied according to the manufacturer's recommendations.
Tail docking of lambs is recommended by the Code of Practice for sheep for blowfly control. Acceptable methods of tail docking, without anaesthesia, are cutting with a sharp knife, rubber rings applied according to the manufacturer’s recommendation, or a gas flame heated searing iron (‘gas knife’) used according to the manufacturer’s recommendations.
It is intended that the Australian Animal Welfare Standards and Guidelines for Sheep will be regulated in Western Australia in the future. Under these standards and guidelines, the following standards apply in regards to tail docking and castration:
- A person performing tail docking or castration must have the relevant knowledge, experience and skills, or be under the direct supervision of a person who has the relevant knowledge, experience and skills.
- A person must not tail dock sheep that are more than six months old without using appropriate pain relief and haemorrhage control for the sheep.
- A person must leave a docked tail stump of a sheep with at least one palpable free joint remaining.
- A person must not castrate or use the cryptorchid method on sheep that are more than six months.
The Department of Agriculture and Food, Western Australia (DAFWA) recommends that producers use rubber rings or a hot gas knife when tail docking. The hot knife method is generally preferable for tail docking on lambs that are also mulesed. If using a hot knife when windy, consider using a wind block to maintain the knife at optimum temperature. A knife that is too cold will not cut through the tail in one motion. A knife that is too hot will cut through the tail too quickly and not cauterise the tail tip and increase the amount of blood loss.
There are two types of gas knives available to producers in Australia, a standard knife and a rotating anvil knife (known as the Te Pari Patesco knife®). Both knives cause similar wounds and work in the same way; however a Te Pari knife has a rotating anvil which stretches the woolly skin prior to cutting, resulting in bare areas on the dorsal tail surface and tip of the tail. This leaves greater bare area, where wool would normally grow and be at risk of urine stain and dags. For more information on the Te Pari knife please see link in the side menu (to flystrike page).
Lambs should be docked to the third palpable joint or to the tip of the vulva in ewes and to the same length in wethers to reduce flystrike risk. Shorter tailed lambs have higher incidences of rectal prolapse and vulva cancer. Tail docking at a shorter length does not necessarily mean less flystrike.