Personality consistency analysis in cloned quarantine dog candidates

In recent research, personality consistency has become an important characteristic. Diverse traits and human-animal interactions, in particular, are studied in the field of personality consistency in dogs. Here, we investigated the consistency of dominant behaviours in cloned and control groups followed by the modified Puppy Aptitude Test, which consists of ten subtests to ascertain the influence of genetic identity. In this test, puppies are exposed to stranger, restraint, prey-like object, noise, startling object, etc. Six cloned and four control puppies participated and the consistency of responses at ages 7–10 and 16 weeks in the two groups was compared. The two groups showed different consistencies in the subtests. While the average scores of the cloned group were consistent (P = 0.7991), those of the control group were not (P = 0.0089). Scores of Pack Drive and Fight or Flight Drive were consistent in the cloned group, however, those of the control group were not. Scores of Prey Drive were not consistent in either the cloned or the control group. Therefore, it is suggested that consistency of dominant behaviour is affected by genetic identity and some behaviours can be influenced more than others. Our results suggest that cloned dogs could show more consistent traits than non-cloned. This study implies that personality consistency could be one of the ways to analyse traits of puppies. Canine behaviour, cloned dog, puppy aptitude test Much effort has been made to assess the personalities of dogs to predict the temperaments of companion animals and to select working dogs more efficiently. Potential dog owners likely want to know their family member’s expected characteristics. Bartlett (1979) explained how to select a family dog using the Puppy Aptitude Test. Adopting suitable animals could be the beginning of a happy life for both owners and the dogs. Breeders need to check the puppies’ temperaments for similar reasons for their future dog owners. Training institutions that produce excellent working dogs focused on selecting candidates at an early age to save money and time. Svartberg et al. (2005) investigated the consistency of dogs’ behaviours using a standardized behavioural test and could deduce stable traits such as playfulness, chase-proneness and sociability. Substantial consistency of dogs’ personalities was reported by Fratkin et al. (2013), who determined the factors that influence consistency as the age, interaction between temperament and age, and length of time interval between tests. These authors did not, however, estimate the influence of the genetic background on consistency (Fratkin et al. 2013). Bartlett (1979) used 10 subtests to analyse puppies’ behaviours, including social attraction, dominant or submissive tendency under stress, willingness to work with humans and sensitivities. Volhard and Volhard (2001) divided the subtests into three drives, ACTA VET. BRNO 2017, 86: 273-283; https://doi.org/10.2754/avb201786030273 Address for correspondence: Byeong Chun Lee, DVM, PhD Department of Theriogenology and Biotechnology College of Veterinary Medicine, Seoul National University 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea Phone: 82-2-880-1269 Fax: 82-2-873-1269 E-mail: bclee@snu.ac. kr http://actavet.vfu. cz/ namely the Pack Drive, the Fight or Flight Drive, and the Prey Drive. The Pack Drive consists of three subtests, which are Social Attraction, Following, and Social Dominance. These factors seem to be related with living in a group of pack of wolves. Fight or Flight Drive includes the subtests Restraint, Elevation Dominance, and Stability. These characteristics are relevant to the ability to struggle or run away. The subtests Retrieving, Sound Sensitivity, and Sight Sensitivity belong to the Prey Drive, which is related to the hunting ability. Personality consistency is expressed as the degree of repeatability of specific traits at various intervals. Netto and Planta (1997) reported that attack scores of adult dogs between two aggression tests were correlated, and Slabbert and Odendaal (1999) found the predictability of behaviour tests targeted for police dogs. They concluded that the most reliable tests were retrieval and aggression tests, and the significance of this research on personality consistency saved unnecessary training efforts and other costs wasted on unsuitable dogs (Slabbert and Odendaal 1999). In contrast, other results showed that fear, anxiety and aggression behaviours were not consistent (Stephen and Ledger 2007). The behaviour of cloned dogs has been studied to determine the similarities among animals (Choi et al. 2014), and the present study attempted to assess the personality consistency of cloned dogs. This investigation was conducted by comparing cloned and control groups for consistency of their Puppy Aptitude Test (PAT) scores. We supposed that personality consistency of cloned animals could be different from naturally bred ones since their aptitude showed differences in the previous study. Therefore, in this project we tried to answer the question: Is personality consistency different between cloned and control groups at 7–10 and at 16 weeks? We used the Puppy Aptitude Test consisting of 10–11 subtests and examined the scores for the Pack Drive, Fight or Flight Drive and Prey Drive (Volhard and Volhard 2001). This behaviour test has been used at the Quarantine Detector Dog Training Centre (Incheon, Korea) to evaluate puppies and improve training methods. This study is the first attempt to assess personality consistency in cloned working dog candidates. Materials and Methods Subjects In this study, six cloned and four control Beagle puppies (Canis familiaris) were compared by the modified Puppy Aptitude Test (Bartlett 1979; Volhard and Volhard 2001). Cloned puppies were produced by somatic cell nuclear transfer (SCNT) (Lee et al. 2005). In brief, donor cells were derived from the abdominal skin of a 10-year-old male Beagle. This dog was selected by handlers and trainers from the Quarantine Detector Dog Training Centre because of his excellent ability in detecting forbidden items at the airport. The role of a quarantine detector dog, also called quarantine dog, is to find forbidden livestock or plant products. This work contributes to disease control by preventing transmission of sources of infection from abroad. Progesterone concentration of oocyte donor dogs was monitored and in vivo matured oocytes were collected three days after ovulation. Cells of the excellent dog were injected into enucleated in vivo matured dog oocytes, and the couplets were fused by electric stimulation and chemically activated. These embryos were transferred into surrogate mothers. All six puppies were born by caesarean section from different surrogate mothers. All operations such as collecting oocytes and caesarean section were performed under general anaesthesia and pain reliever was injected after operations. Control puppies were produced by artificial insemination. We transferred several embryos into surrogate mothers and four of them were successfully conceived. Procedures to collect in vivo matured oocytes were the same as the cloned ones and the male dog was selected randomly as if it occurred in natural breeding. Therefore, control and cloned puppies do not have genetic relations. One of the four control puppies was born by caesarean section and three of them were born by natural birth which was judged by the state of foetuses. These three puppies were littermates and the birthdates of all of the puppies are presented in Table 1. They were raised as candidates for quarantine dogs with other puppies at the Quarantine Detector Dog Training Centre. After birth, all of the puppies were monitored for 24 h at neonatal care until they became one week old. They stayed with their surrogate mothers by the weaning period. The birthdates of the puppies were different as mentioned in Table 1, though they were cared for by the same keepers and handlers. Their living quarters and food 274