Behavioral reactivity of Jindo dogs socialized at an early age compared with non-socialized dogs.

The aim of this study was to determine whether socialized Jindo puppies would show different behavioral reactivity from non-socialized puppies. Puppies (n=12), 7 weeks of age, were divided into socialized and non-socialized groups. The socialized group from the 7th until 13th week after birth was provided a socialization program, and the non-socialized group was reared in a semi-isolated environment without being exposed to the program. At 13 weeks after birth, both groups were adopted by new families and raised as a family pet until adulthood. Both groups were tested in 5 behavioral tests at 7, 9, 11, 13 and 60 weeks of age, and their behavioral responses to the tests were recorded using video cameras. The contact, fearful and playful behaviors toward each behavioral test were scored on a scale of 1 to 5 points. Using all of the score data, a principal component analysis (PCA) extracted three primary factors: 'social reactivity towards humans and a dog', 'playful reactivity towards novel stimuli and a dog' and 'fearful reactivity towards social stimuli'. The three extracted factors were compared between the socialized and non-socialized groups in each test session (weeks). Based on the results, the socialized Jindo puppies in the test session at the 9th week after birth, in contrast to the non-socialized puppies, exhibited a higher intensity of playful reactivity towards novel stimuli and a dog. However, there were no effects of the socialization program on the Jindo puppies in terms of social reactivity towards humans and a dog as well as fearful reactivity towards social stimuli.