title: A method to determine integrated steroid levels in wildlife claws.
abstract: Glucocorticoids act throughout life to regulate numerous physiological and behavioral processes. Their levels are therefore highly labile, reacting to varying conditions and stressors. Hence, measuring glucocorticoids (and other steroids) in wildlife is challenging, and devising methods that are unaffected by the stress of capture and handling should be explored. Here we use the tip of free-ranging chameleons' claws that were cut to allow individual identification, and report a steroids extraction and quantification method. Claw steroids present an integrated level representing the period of claw growth. We found that we could measure corticosterone in small amounts of chameleon claw matrix using commercial EIA kits. Using this method, we learned that in wild male chameleons, claw corticosterone levels were associated with body size. We suggest that claw-testing can potentially provide an ideal matrix for wildlife biomonitoring.
authors.affiliation: The Mina and Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel.
authors.forename: Devorah
authors.initials: D
authors.lastname: Matas
authors.affiliation: Zoology Department, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Tammy
authors.initials: T
authors.lastname: Keren-Rotem
authors.affiliation: The Mina and Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel. Electronic address: Lee.Koren@biu.ac.il.
authors.forename: Lee
authors.initials: L
authors.lastname: Koren
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000033:anatomy & histology*; D049628:Body Size; D003345:Corticosterone / Q000032:analysis* / Q000302:isolation & purification*; D004784:Environmental Monitoring / Q000379:methods*; D006724:Hoof and Claw / Q000737:chemistry*; D007124:Immunoenzyme Techniques; D008116:Lizards / Q000033:anatomy & histology*; D008297:Male
chemical_list: D003345:Corticosterone
keywords: Chameleon; Corticosterone; Glucocorticoids; Nails; Non-invasive; Reptiles