Abstract # 1891 Poster # 59:

Scheduled for Thursday, August 17, 2006 07:00 PM-09:00 PM: Session 8 (Regency West 1/3 ) Poster Presentation

Hair Loss and Replacement Cycles in Socially Housed, Pregnant, Rhesus Macaques

E. B. Davis1 and S. J. Suomi2
1NIH/NICHD/ Research Animal Management Branch,, NIH Animal Center, P.O.Box 529, Poolesville, Maryland 20837, USA, 2NIH/NICHD Laboratory of Comparative Ethology
     In the natural world a coat of hair is usually viewed as being vital for the survival of an animal. Hair often grows at distinct specialized skin sites and appropriate hair types and lengths are also grown by the organism to adapt it to environmental and climatic changes. Hair coat conditions may also reflect an individual's overall fitness level as well as advertise its rank and sexual status. The production of hair and the cycling processes it goes through are complex and the target of many interrelated endocrine systems. Our study investigated a group of socially housed rhesus macaques (Macaca mulatta), housed in an indoor/outdoor run, consisting of 2 males and approximately 10 to 13 breeding females. These animals were photographed at monthly intervals over a 3-year period (2003 - 2006). Photos were taken to assess hair coat condition, replacement intervals, and to assess if photoperiod was the main driving force behind hair coat condition. To our surprise our photos illustrate a rigid hair loss/re-growth pattern that occurred only in our pregnant females. Hair loss was noted throughout the gestation period and re-growth occurred immediately after parturition. These loss and re-growth patterns did not correlate with any seasonal photoperiod episodes. Although our photographs illustrate a direct connection between pregnancy and coat conditions there is a need to further explore the systematic endogenous factors involved in this non-seasonal event.