TY JOUR TI THE ROLE OF THE PTARMIGAN (Lagopus lagopus Montin.1776) CAECUM IN THE REGULATION PROCESS OFMICROELEMENT STRUCTURE KW ptarmigans KW heavy metals KW caecum KW nutrition JO Bulletin of KSAU AU Kochkarev, P.V. PY 2014 IS PB Krasnoyarsk State Agrarian University