Catalan sheepdogs exhibiting basic herding instincts can be trained to compete in herding trials. Icelandic Sheepdogs that exhibit basic herding instincts can be trained to compete in herding trials. Frequency is high in Collies and Shetland Sheepdogs, and low in Border Collies and NSDTRs. In Australian Shepherds, Rough Collies, and Shetland Sheepdogs, blue means a blue (black-based) merle. The Polish sheepdogs were bred with local Scottish dogs to produce the Bearded Collie. Welsh Sheepdogs can be trained to compete in stock dog trials. Russian sheepdogs are not mentioned in these records, nor are any other working dog breeds. Since wolf and bear have returned, the use of Maremma Sheepdogs is not unusual. Catalan sheepdogs are prone to hip dysplasia. A shepherd's whistle is traditionally used for communicating commands to sheepdogs. There are also competitive shows for dogs, sheepdogs, and cats. She had previously been well known for breeding Old English Sheepdogs. Old English Sheepdogs only shed when they are brushed. Polish Lowland Sheepdogs are stable and self-confident. Old English Sheepdogs should not be deprived of the company and the warmth of people.