An undercoat rake is a pet grooming tool which is designed to remove hair from an animal's soft, loose undercoat without disturbing the longer hairs of the upper coat. These tools are extremely useful for brushing out animals in the late spring and early summer, when the loose undercoat can become unbearably hot, and they also help to dramatically cut down on shedding. A good undercoat rake can also promote skin health by gently stimulating circulation to the skin and removing dead skin.
Most pet supply stores sell undercoat rakes, which may come in several sizes. A cat undercoat rake is typically smaller, with very closely spaced teeth, while rakes designed for dogs are a bit larger. It is also possible to use undercoat rakes on larger animals like sheep and llamas, along with animals such as bunnies; if you have an angora rabbit, for example, an undercoat rake can be used to gently remove the rabbit's loosened fur for spinning into yarn.
A typical undercoat rake looks a lot like a rake, with flexible stainless steel teeth which are typically set close together. In some cases, two rows of offset teeth are used, to enhance the gripping power of the grooming tool. To use an undercoat rake, groomers simply gently run it over the animal, keeping the handle as upright as possible and being careful not to dig into the animal's skin with the teeth, which can be sharp and uncomfortable.
When an undercoat rake is used, the stiffer upper hairs of the animal's coat will slide through as the rake removes loosened hairs in the undercoat. These hairs tend to be fine and extremely soft, and they can clump quickly, so it is a good idea to clean the undercoat rake several times as you use it. For animals which are shedding, the undercoat rake can be a great tool, increasing comfort and reducing the risk of matting; undercoat rakes can also be more generally used to help take out mats.
When seeking out an undercoat rake, you may want to find one with a soft, flexible handle which will feel comfortable as you use it. It is also a good idea to find an undercoat rake which can be dipped in disinfectant periodically, and between animals. Consider the size of the animal that the rake will be used on; you may want to gently test the tines against the soft skin of your inner arm to ensure that the rake feels comfortable.