I wanted to share a few thoughts on the Freeze branding process and how to get the best results. We have been very busy lately branding heifers pre- turnout. Here are some key facts which help explain the method we use to provide permanent ID on cattle.
Freeze branding uses copper alloy irons chilled in a solution of dry ice (frozen C0²) and an alcohol solution of Isopropanol (methylated spirits). On darker haired cattle application of these chilled irons alters the pigmentation of the underlying hair follicles (turning black/coloured hair white). Freeze branding was first developed in 1966 by Washington State University and has predominantly replaced the use of hot branding. Studies from the USA provide clear evidence that in comparison to hot iron branding, freeze branding causes less of a stress response in cattle (smaller increase in heart rate and fewer circulating stress hormones). This must mean that the cattle experience a lower level of pain.
The cattle are clipped in the desired area and brushed with isopropanol which creates good contact with the skin. The irons are chilled to -78°C in the dry ice solution (which takes about 20 minutes), and then placed onto the area to be branded, held in place with slight pressure. Darker cattle require about 30 seconds of contact time, with around one minute for lighter coated animals. A healing period follows the branding, with scabs forming over the branded area. This process is completed within around 3 months by which time the cattle are permanently identifiable.
It is really important that the cattle are adequately restrained – no sideways movement or jumping around! Heifers can be lively so plenty of help and a decent crush are essential. A squeeze crush can be really useful, or alternatively one that is “narrowed” using a tyre or pallet to avoid sideways movement. Failure to adequately restrain the animals results in a poor quality brand that may be unreadable! We need to organise sufficient dry ice for large sessions, so please help us by booking in good time, ideally with a few weeks notice.
Written By James Perrett, Vet Tech
