Donald Shaver search widely for diversified breeding stock. Local breeders, knowing his reputation were reluctant to sell to him for fear of competition. In 1946, there were 256 registered chicken breeders in Canada. Shaver Poultry became the 257th. By 1958, only Shaver remained, along with seven other major poultry breeders worldwide. The principle of hybrid vigour had been well established for corn, but the costs and time required to test chicken crosses were higher. Small breeders (as Shaver was at the time) could not afford permanent scientific staff, so Shaver obtained assistance from geneticists conducting research at universities and government institutions. Shaver
Callus shaver is shared with others and not properly sterilized. In very severe cases, amputation or death can result. Treatment with a callus shaver should involve the user in a longer-term care plan. Calluses are usually several skin layers deep, which means that treatment must be repeated several times on the affected area (usually the feet) if it is to remain callus free. However, there should be a period of a few days between the individual treatments, otherwise skin irritations and/or an even thicker callus may occur. The callus shaver should not be confused with a foot file (foot rasp), which is