Table 1 Features of cost, accuracy and data storage of different technologies used to infer ovine heat stress
From: Technologies for the automated collection of heat stress data in sheep
| Technology | Model/type | Cost per unit (AUD) | Sensor accuracy | Data collection | Ovine studies |
|---|---|---|---|---|---|
| Temperature loggers (thermistors/thermocouples) | Thermochron iButton (OnSolution, Maxim International) | 98 + software and deployment strategy | ± 0.5 ℃ | Data storage, up to 6 months of data in memory, 1–2 year battery life | [15, 51, 53, 85, 124] |
| DST Micro loggers (StarOddi) | 475 + communication box (545), Mercury software (370) + deployment strategy | ± 0.06 ℃ | |||
| Automated tympanic probes | FeverTags®, Cow Manager, DoggTag, SenseTag, TekVet | 25–40 | ± 0.1 ℃ | Data storage, > 2 year battery life | [124] |
| Reticulorumen boluses | Smartstock, USA | 70 + station (960) and receiver (1790) | ± 0.2 ℃ | Wireless data transmission up to 200 m | [66, 69,70,71, 125, 126] |
| Infrared Thermography | IRT Thermometer; VTTS-1000 Tympanic Scanner Exergen Corporation® | 100 | 2 ℃ or 0.5% | Manual thermometry | [96, 127] |
| IRT Camera | 1000–4300 | < 0.1 ℃ ± 2% | Contactless, > 3000 m range | [25, 85,86,87, 128,129,130] | |
| Implantable devices | LifeChip® microchips with BIO-THERM® sensor | 20–50 | ± 0.5 ℃ | Data storage activated through handheld receiver | [15, 66, 86] |
| GPS collars | UNETracker, WildTrax, EarTrax-AG | 2000 | 5–10 m | Data storage | [26, 115,116,117,118] |
| Accelerometers | HOBO Pendant G data loggers | 195 | Up to 99% | Data storage & wireless transmission | [108, 112, 117, 131] |
| ActiGraphs | 290 | [109] |