Freeze branding In response to intense consumer pressure for an alternative to mulesing an adaptation of the
freeze branding branding process was hit upon in the 2010s. The new technique was soon christened
steining after its developer, John Steinfort, an Australian veterinary scientist. In 2019 Australian Wool Network (AWN), a private corporation servicing the Australian wool industry, provided Steinfort funding to commercialize the technique. During
steining a set of clamping jaws designed by Steinfort is used to pinch up rolls of skin near the tail and anus of a lamb. Once sufficient skin is in the clamps liquid nitrogen is pumped through the jaws and onto the pinched skin. This rapidly freezes the lamb's skin. The goal is to achieve the level of cellular injury that prevents future hair growth but not so much that a 3rd degree cold burn is created. Pinching the skin is thought to mitigate the degree of the cold burn by removing it somewhat from the muscles and
connective tissue beneath. The treated skin goes through the same stages of healing seen in the long method of freeze branding, terminating with permanent hairlessness. Studies show this method is at least as good at preventing flystrike as mulesing and carries few long-term consequences for the lamb's later growth and wool production. Steinfort and others invested in the process have claimed it is less painful and distressing to the animals on which it is practiced. They argue that affected nerve endings are immediately numbed and that sensation does not return during healing, when a scab forms and is eventually sloughed in 6 to 8 weeks. A 2018 study found behavioral markers indicating pain and distress in lambs who had been steined without analgesic treatment compared to those who had been given analgesics. In 2020 a
University of Melbourne researcher named Ellen Jongman was commissioned to study the issue by the company Steinfort formed to commercialize his technique, SteinfortAgVet. The name of Steinfort's company subsequently changed to AgVetInnovations. In March of 2021 AWN cut ties with Steinfort and divested from this application of freeze branding.
Breeding programs As of 22 July 2021 the position of the
RSPCA is that Australian Merino sheep have not been ethically bred, as seen in their susceptibility to flystrike. They believe "any painful procedure to change the breech area should only be considered an interim, short-term solution that accompanies a breeding program that focusses on flystrike resistance, and is carried out only where absolutely necessary to manage at-risk sheep." Merino sheep bred on selection principles may be more resistant to flystrike because they are plain bodied (lower skin wrinkling around the breech). Studies have shown that flystrike is lower in plain bodied sheep. However, mulesed animals had consistently lower flystrike than unmulesed regardless of body type. The resistance of plain-bodied Merino sheep to flystrike arose from field investigations by Australian scientists, Drs H. R. Seddon and H. B. Belschner, in the early 1930s. Non-mulesed Merino ewe bodies were graded as plain (A class), wrinkly (B class) and very wrinkly (C class). The plain-bodied (A class) Merino ewes were much less susceptible to flystrike than wrinkly-bodied Merinos (B and C class). In these Merino flocks, the sheep are plainer than the plain-bodied (A class) Merino ewes and therefore more resistant to flystrike. The rams and
semen from these studs are used in over 3,000 of the 45,000 Merino farms in Australia. Using breeding principles, wrinkle-skinned Merino flocks which require mulesing have been transformed into plain-bodied and mules-free flocks within five years. and even early reviews proclaimed the effectiveness of using dip across the whole animal, rather than cutting one small portion that left the rest of the animal still susceptible "dipping is still the most cost-effective means of protecting sheep from flystrike". • Topical protein-based treatments which kill wool follicles and tighten skin in the breech area (
intradermal injections) • Biological control of
blowflies. • Plastic clips on the sheep's skin folds which act like castration bands, removing the skin (
breech clips). ==See also==