Diferencias individuales en los perros domésticos (Canis familiaris): Revisión de las evaluaciones conductuales

a review of the research on individual differences in domestic dogs is presented in this paper. temperament has been defined as the group of individual differences in behavior which is manifested steadily across situations and over time. it has been studied in a wide range of species including humans. domestic dogs have undergone intense processes of selection on behavioral traits during domestication, and in the development of different breeds. these processes produced a great morphological, genetic and behavioral variability, which turned the dog in an interesting model for the study of individual differences. in this study we present a review of the different test batteries developed for the assessment of various behavioral traits. test batteries are defined as standard experimental situations where a stimulus is used to provoke a behavior which is compared statistically to that of other individuals in the same situations, in order to classify the subjects. to achieve this aim, a brief description of seven batteries is given. four of them evaluated dogs from breeding or train ing centers. their aim was to select those animals which possess the most adequate traits to become guide or police dogs. the remaining batteries evaluated shelter dogs in order to elaborate a behavioral profile to improve the adoption process. in each battery described we analysed the operational definitions of the variables, the method used for scoring the animal's responses (overall vs. direct), the use of trained observers and the different types of stimuli used. the behavioral traits that are mainly assessed in dogs are fearfulness, aggressiveness, responsiveness to training, and sociability. fearfulness is generally assessed through the appearance of a startling stimulus, which can be intense or not, such as the reaction towards a strong noise, the open ing of an umbrella, or the sudden appearance of a human figure. aggressiveness is measured through the reaction towards a threat or pr