Iptt 300 temperature transponder

Mice 8 weeks of age were transferred to a 30°C chamber (thermoneutrality) for two weeks. One week before cold exposure, IPTT-300 temperature transponders (Bio Medic Data Systems) were implanted subcutaneously in the dorsal region of the mice. Body temperature was assessed using a DAS-7006/7 s reader (Bio Medic Data Systems). The mice were then transferred to the cold chamber (6°C) or maintained at thermoneutrality. For the acute cold tolerance test, food was removed from the cages upon transfer to the cold chamber and body temperature was measured at the indicated time points. For the acclimated cold exposure test, food was removed from the cages after 4 weeks of acclimation to cold and body temperature was measured at the indicated time points.

Mice were housed for the duration of the testing in a temperature-controlled animal housing facility monitored and maintained at a temperature of 22°C ± 0.4°C at Stanford University. A temperature probe (14 × 2.2 mm, 120 mg, IPTT-300 Temperature Transponder, Bio Medic Data Systems) was implanted subcutaneously dorsal and lateral to the L1–L4 region of the mouse, with a reported accuracy of ±0.6°C (63 (link)). After 3 days, body temperatures were measured in the morning and afternoon using a scanner (DAS-8007IUS Reader, Bio Medic Data Systems) that allowed for temperature measurements in conscious mice in home cages.

Energy balance parameters, including locomotor movement, ambulatory activity, feeding, drinking, and calorimetry, were simultaneously assessed by the comprehensive lab animal monitoring systems (CLAMS, Columbus Instruments). Twenty-four hour urine monitoring and collection, and additional monitoring for accumulative food and water intake were assessed in metabolic cages (TECNIPLAST). Lean body mass was assessed with dual-energy X-ray absorptiometry (DEXA, Lunar PIXImus). Baseline body temperatures were assessed with IPTT-300 temperature transponder (BioMedic Data Systems) for repeated measurements, and with RightTemp^® rectal thermometer (PhysioSuite^®, Kent Scientific) for one-time measurements. Temperature acclimation to cold (4 °C) or warm (30 °C) condition was regulated by the environment-controlled enclosures (CLAMS-ENC70, Columbus Instruments). For experiments requiring temperature conditioning, mice were conditioned at the specified temperatures for 1 week prior to assessment for thermogenic capacity. To determine the effects of temperature conditioning on adaptive thermogenesis, core body temperatures were measured between 1 and 2 h after return to room temperature following the conditioning at either 4 or 30 °C. All temperature measurements were performed during the same time each day in the afternoon (2:00–4:00 pm) to reduce influences from circadian regulations.

A registered veterinarian performed daily clinical monitoring of infected rabbits for signs of malaise and neurological deficit. Measurements of rectal (for NZWRs) or body (for CTRs) temperature, as well as their weights were taken daily. For NZWR rabbits, a standard electronic thermometer was used per rectum. An IPTT300 temperature transponder (BioMedic Data Systems, Inc., Seaford, DE, USA) was implanted subcutaneously in CTRs for daily temperature measurement. The approximate size of both the draining and contralateral PLNs was also gauged by palpation in the NZWR groups. The general alertness, as well as food and water intake, were used as indicators of their well-being. Daily neurological examination by the hopping test was performed on NZWRs to observe for significant loss of coordination of hind and forelimbs [59 ]. Other neurological signs such as seizures and muscle twitching were monitored.