title: The behavioral and endocrinological development of stress response in dogs.
abstract: Endocrinological stress response has been shown to be absent in a specific period of the early life of rodents; this is named the stress-hyporesponsive period (SHRP). The SHRP is a significant period for the appropriate development of infants. In this study, the presence of SHRP in dogs was identified by conducting a 5-min separation test in 142 Labrador retriever puppies in their early socialization period and measuring the changes in urinary cortisol levels. An increase in cortisol after separation was found after 5 weeks of age, suggesting that the SHRP persists until 4 weeks of age in dogs. The distress vocalization during separation changed and the lactating behavior decreased rapidly around 5 weeks of age, suggesting that the endocrinological and emotional aspects of development change at approximately 5 weeks of age and maternal inhibition of cortisol might occur in dogs as well as rodents.
authors.affiliation: Department of Animal Science and Biotechnology, Azabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa, 252-5201, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Nagasawa
authors.forename: Yoh
authors.initials: Y
authors.lastname: Shibata
authors.forename: Akiko
authors.initials: A
authors.lastname: Yonezawa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Morita
authors.forename: Masanori
authors.initials: M
authors.lastname: Kanai
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Mogi
authors.forename: Takefumi
authors.initials: T
authors.lastname: Kikusui
mesh_terms: D000818:Animals; D004285:Dogs; D004644:Emotions / Q000502:physiology; D006854:Hydrocortisone / Q000652:urine*; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology; D008426:Maternal Deprivation; D010913:Pituitary-Adrenal System / Q000503:physiopathology; D013315:Stress, Psychological / Q000503:physiopathology* / Q000652:urine
chemical_list: D006854:Hydrocortisone
keywords: cortisol; dog; maternal behavior; stress-hyporesponsive period; vocalization