Barrier 208a

Male Sprague-Dawley rats (Rattus norvegicus) were purchased from Envigo (Barrier 208A, Frederick, MD, USA) at approximately 30 days of age and 75–100 g body weight. All animal research conducted under this project was approved prior to initiation by the Armed Forces Radiobiology Research Institute (AFRRI) Institutional Animal Care and Use Committee (IACUC) under protocol 2016–05-006. Further, all procedures were conducted in compliance with guidance found in the Guide for the Care and Use of Laboratory Animals (National Research Council, 2011 ) in an Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC)-accredited research facility. After arriving at the AFRRI vivarium, rats were allowed to acclimate for at least 2 weeks prior to experimentation. Animals were pair-housed throughout the study in plastic microisolator cages with filter tops. Bedding (Teklab Sani-Chips, Envigo) was changed 2–3 times per week. Vivarium rooms were maintained at 21 ± 2 °C with 30–70 % humidity. The rooms were maintained on a 12:12-h light:dark cycle with lights on at 0600. Animals were fed standard rodent chow (Teklad Global Rodent Diet 8604, Envigo) with water available ad libitum.

All animal research in this study was approved prior to initiation by the Armed Forces Radiobiology Research Institute IACUC under protocol number 2016−05-006. All procedures involving animals were conducted in compliance with the guidelines found in the Guide for the Care and Use of Laboratory Animals [46 ] in an AAALAC-I-accredited facility. Male Sprague-Dawley (Rattus norvegicus) rats were utilized in these experiments and were obtained from Envigo (Barrier 208A, Frederick, MD) when approximately 30 days old and 75−100 g. After arriving at the AFRRI vivarium, rats were allowed to acclimate for at least 2 weeks prior to the start of experiments. Rats were pair-housed throughout the study in plastic microisolator cages (23.8 × 45.4 cm) with filter tops and bedding (Teklab Sani-Chips, Envigo). Bedding was changed 2–3 times per week. Animal rooms were maintained at 21 ± 2 °C with 30–70% humidity and a 12:12-h light:dark cycle (lights on at 0600). Rats were fed a standard rat chow (Teklad Global Rodent Diet 8604, Envigo) with access to water ad libitum.