When training a dog for a true trailing dog to be used in the area of search and rescue there must be a definite understanding that you are NOT training for an A.K.C. title. Often the attainment of an A.K.C. title has nothing to do with following human scent nearly as often as it has to do with following the requirements that the handler sets up for the dog. Also, the motivation usually is pieces of hot dog which are laid on the track by the person who "sets" or "lays" the track.
A person training a dog for trailing must learn first the theory of scent and skin rafts; that a human being will constantly drop skin cells and that these cells form a "raft" which will drift with the wind and fall to the ground as the person moves. It is this trail of skin cells, which the trailing dog must be trained to follow. How and where the skin cells land on the surrounding vegetation or surface will determine how and where the trailing dog will locate the scent. The length of time that the scent may be picked up by the dog will depend on the quality of the training and the natural abilities of the dog, along with the effects of weather on the trail. The other requirement for successfully training a trailing dog is that the handler motivates the dog so that he will not deviate from the trail under any circumstance.
A person training a dog for a tracking title is not concerned with the life and death scenario of a true search "mission" but rather is concerned with the attainment of a title, which can only be earned by following a prescribed "track" which has been laid in a specific manner for the dog. Training for this title often involves the use of hot dog pieces laid in the track of the human, thus encouraging the dog to follow the exact foot impressions on the ground.
A person who is training a dog for certification as a "trailing dog" in the search and rescue area recognizes that the dog MUST be motivated to follow the trail of the rafts of skin to the source. The use of food, if used at all, must be limited to a reward after the trail is correctly followed. The major emphasis on training the trailing dog must be one of setting up many many different scenarios and using many different "victims", all the while recognizing that the task of the handler is to learn to recognize how the dog is reading the trail and to train the dog to identify the trail correctly through scent discrimination.
The best motivation is without a doubt the strong desire to find a human and the old standby from the beginning for this type of motivation is the "puppy runaway" which has been the basis for the training of search dogs for many many years. The difference between training an area wilderness search dog and a scent discrimination trailing dog is simply that the dog's exposure to air scenting is limited as much as possible during his early training. The human's task is to learn to "read" the dog and also to discover how the wind carries and distributes the skin cells and lastly but most importantly to motivate the dog throughout the training to want to follow the trail to its source.