Your subscriptions

You are here

Homeagain Frequently Asked Questions

Frequently Asked Questions

  • How does HomeAgain® Thermochip® (Mini) work?

    HomeAgain Thermochip and Thermochip Mini work in the same way as any other classical pet identification microchip to improve the chance of a pet being reunited with their family should they ever become lost.

    In addition to acting as an identification microchip, HomeAgain Thermochip has an integrated temperature biosensor, which makes it possible to collect measurements of an animal's subcutaneous temperature at the location of the microchip. HomeAgain Thermochip can measure the temperature in the range of 33 °C to 43 °C.

    The temperature at the implantation site and the identification number can be read simultaneously using a compatible microchip reader, such as the SureSense® Universal Microchip Reader or Global Pocket Reader® Plus (GPR+).

    Multiple temperature values collected consecutively or regularly (during the daytime for several days, in the early morning and/or in the late evening) can establish a trend for an individual animal’s profile and daily variations.


    A closer look at the components of the HomeAgain Thermochip

    Image the components of the HomeAgain Thermochip

  • Regarding thermometer calibration how does a HomeAgain Thermochip compare to a classic digital thermometer?

    Classic digital thermometers use an external probe which encapsulates the electronic heat sensors to capture body temperature measurements directly. It is necessary to calibrate a classic digital thermometer as the accuracy can drift over time for various reasons such as mechanical shock.

    HomeAgain Thermochip uses a different temperature measurement technology as the temperature biosensor is fully integrated in the microprocessor of the bioglass-encapsulated microchip, thus protecting the device from mechanical shock. 

  • How does the HomeAgain Thermochip temperature biosensor work?

    HomeAgain Thermochip has a pair of transistors built into the chip integrated circuit. The transistors’ junction voltages are proportional to the temperature, and this is what allows the microchip to produce an output signal that is proportional to temperature. This signal is further converted to a digital value. The SureSense® Universal Microchip reader and Global Pocket Reader® Plus read the HomeAgain Thermochip and convert the digital value to its corresponding temperature value.

    How HomeAgain Thermochip microchips and readers work together

    Image of How HomeAgain Thermochip microchips and readers work together

  • Which reader can display HomeAgain Thermochip information?

    A HomeAgain Thermochip's microchip number can be read by all ISO microchip readers, just as for any other microchip. We recommend using the SureSense Universal Microchip Reader or the Global Pocket Reader Plus (GPR+) reader to read the temperature value of HomeAgain Thermochip.

    We can ensure the reliability of the temperature value transmitted by HomeAgain Thermochip with our readers SureSense and GPR+. We don’t know how other readers could interpret the signal sent by HomeAgain Thermochip and therefore we cannot ensure the reliability of the temperature data that other readers may be displaying.


                        Global Pocket Reader Plus reader scanning a dog                                                                     

    Image of Global Pocket Reader Plus reader scanning a dog


       SureSense Universal Microchip Reader scanning a dog

    Image of SureSense reader scanning a dog

  • Does HomeAgain Thermochip have a battery inside?

    No, HomeAgain Thermochip is a passive and inert identification microchip which stores a unique and locked 15-digit identification number. HomeAgain Thermochip is a certified and ISO compliant identification microchip. It has no battery and no other internal power source. The identification number and the change to the animal's temperature can be read scanning with an adapted reader such as the SureSense Universal Microchip Reader or the Global Pocket Reader Plus (GPR+).

  • Is HomeAgain Thermochip safe for pets and horses?

    HomeAgain Thermochip is encapsulated in a biocompatible and inert material called Bioglass commonly used for the manufacturing of classical pet microchips used by veterinarians or certified implanters for more than 15 years.

    Packed in a sterile-proven disposable syringe, HomeAgain Thermochip is certified by the International Committee for Animal Recording (ICAR – and is as safe as any other pet identification microchip.

  • Can I implant a HomeAgain Thermochip in an animal if they are already microchipped?

    If the animal’s identification microchip works, we strongly recommend that you do not microchip the animal again with a HomeAgain Thermochip. Double microchipping is not recommended for regulatory and traceability reasons, as two microchips implanted in the same animal at close distance would bring interferences during the reading, thus resulting in microchip reading failure.

  • Is HomeAgain Thermochip available for the identification of ALL species?

    HomeAgain Thermochip is a permanent identification microchip recommended for the identification of dogs, cats, ferrets, pet rabbits, small mammals, birds, and equine. There are 2 sizes available: HomeAgain Thermochip is the classic size, which is 2.12mm in diameter and 13mm in length and packed in a 12-gauge needle; and the HomeAgain Thermochip Mini, which is 1.5mm in diameter and 10.7mm in length and packed in a thinner 14-gauge needle.

  • Is HomeAgain Thermochip a mini-sized identification microchip?

    No, HomeAgain Thermochip is a standard-sized identification microchip - having the size of 2.12mm in diameter and 13mm in length – packed in a 12-gauge needle.

    HomeAgain Thermochip Mini is a mini-sized Thermochip, which is 1.5mm in diameter and 10.7mm in length and packed in a thinner needle size (14 gauge).

  • How does the temperature measured by a HomeAgain Thermochip compare with rectal temperature readings?

    HomeAgain Thermochips are designed to monitor an animal’s individual temperature range to assist in identifying variation in temperature from an individual’s baseline readings with ease.

    Some recent studies conducted both in humans and in pets highlighted the importance that the individual normal temperature is not a specific number, but rather a range of values that depends on the time of day, the site of measurement, and the person’s age 1,2,3,4.

    In dogs, the temperature might also vary in different locations. Indeed, some recent studies aiming to compare different temperature reading techniques demonstrate that body temperature varies by location5. For instance, the results of recent investigations are indicative that the ear and rectal temperature readings should not be directly compared in dogs and cats, but rather compared against a reference range of temperatures for that particular site6.

    Consequently, the temperature values collected using HomeAgain Thermochip do not aim to be compared with the rectal temperature values and does not aim to replace this technique widely used by veterinarians. The best approach is to understand an individual’s reference range for a particular site.

  • What is the reading distance of HomeAgain Thermochip?

    HomeAgain Thermochip is primarily an identification microchip for companion animals compliant with the ISO 11785 standard using the FDX B reading technology. As a passive radio-frequency identification tag operating at the low frequency of 134.2 kHz, readers will work at close proximity, with a read range of up to 10 cm on average.

    An increased read range can be observed (up to 20 cm) but would only rely on the position of the microchip in the animal AND on the performance/quality of the reader used.

  • What is the precision of the temperature value collected by HomeAgain Thermochips?

    An independent laboratory study was conducted to evaluate the accuracy of the temperature-sensing identification microchip using a calibrated methodology.9

    The trial consisted of collecting the microchip temperature values from 10 HomeAgain Thermochips (sampled randomly from two different production lots) and by 4 thermometers of different brands, which were all placed in a calibration bath. Temperature values were collected at every 0.5 °C between 33 °C and 43 °C.

    The average of the microchip temperature values collected, and the ones measured by the 4 thermometers were quite similar, with a difference range varying between 0 °C to 0.18 °C.

  • Is there an influence of external temperature on HomeAgain Thermochip temperature?

    HomeAgain Thermochip displays the animal’s temperature at the implantation site. In pet animals, HomeAgain Thermochip is placed subcutaneously. Any factor that can influence subcutaneous temperature, will have an impact on the HomeAgain Thermochip temperature. Both freezing weather and a thermic blanket (in contact with the skin above the HomeAgain Thermochip) may have an impact on the HomeAgain Thermochip temperature value. This is another reason why it is recommended to study temperature variations with HomeAgain Thermochip, and not the value itself.

    For horses, the implantation of HomeAgain Thermochip is deeper leading to a lower impact of the external temperature on the HomeAgain Thermochip temperature.

  • Does Magnetic Resonance Imaging (MRI) affect the functionality of implanted temperature-detecting microchips such as HomeAgain Thermochip?

    Two recent studies showed that MRI with a 1.0-T magnet should not induce microchip failure. The first study concludes that the microchips tested do not pose any safety hazard to patients undergoing MR imaging with this 1T system. The second study concludes that site of imaging, mean MRI scan time, brand or frequency of microchip did not affect the functionality of the microchip.7,8

    These two recent clinical studies demonstrate that MRI does not interfere with the functionality of the implanted microchips (the microchip numbers have been successfully detected and read). Based on these results and the fact that the temperature-detecting feature and the microchip number are two inseparable data sets, contained in the same integrated circuit, we can conclude that MRI should not be a potential cause of temperature-detecting microchip failure.

  • What prevents the microchip from migrating?

    All HomeAgain microchips are coated in parylene, a transparent, inert, biocompatible substance, applied to the surface of the bioglass-encapsulated identification microchip at the end stage of the manufacturing process. Parylene exerts cell adhesion properties with surrounding tissues, favouring tissue adhesion10.

  • How robust are HomeAgain Thermochip microchips?

    HomeAgain Thermochip microchips are of the highest quality and robustness. They meet the most critical mechanical properties standards applied to microchips for shock (IEC 60068-2-27) and for vibration (IEC 60068-2-6). As part of the quality control procedure, internal drop testing is conducted using stressful demanding conditions that are more challenging than in real life.

  • Can microchips migrate once implanted into an animal?

    A laboratory trial published in 1999 was conducted in 15 adult beagle dogs to investigate the level of migration of 90 microchips manufactured by 2 different companies implanted in 6 different locations (lateral neck, cranial and caudal to the shoulder on both sides). This demonstrated that microchips at all the sites had migrated to some extent (>1cm), and that the migration started early and continued over time. The microchips at the shoulder sites migrated more commonly than those at the head sites. There was no significant difference in migration between the 2 types of microchips used in the study.12

    However, microchip migration has limited effects on the animal providing the microchip can be read and remains functional. This was the conclusion of a report published in 2010 by the Microchip Advisory Group as part of The British Small Animal Veterinary Association, which consolidated all microchip reactions reported by veterinary practices and implanters between 1996 till 2009.13

    Furthermore, the incidence of chip migration remains low in the UK, at 0.01%. Since the Compulsory Microchipping law that came into force on April 6th 2016 in the UK, the reporting of any Microchip Adverse Reaction became compulsory and must be declared to the Veterinary Medicine Directorate (VMD). From April 2014 till December 2015, 1.6 million pets were identified. During this period, 1420 adverse reactions were reported, including 729 migration cases. Among these 729 cases, only 302 have been qualified by the authorities as “true” migration issues, providing an incidence of 0.01%.14

To report an adverse reaction or product-related problem with HomeAgain microchips please fill in an adverse event form or alternatively call MSD Animal Health on 01908 685685.

For any further questions please contact us at and a member of our team will respond to you as soon as possible.



1. Body heat: Older is colder. Harvard Health Letter Vol 31. Number 6. April 2006, p6.

2. Gomolin IH, Aung MM, Wolf-Klein G, Auerbach C (2005). Older is colder: temperature range and variation in older people. J Am Geriatr Soc. 2005 Dec; 53 (12):2170-2.

3. Refinett R. et al. (2003). Daily rhythmicity of body temperature in the dog. J Vet Med Sci. 65(8):935-7.

4. Piccione G. et al. (2010). The daily rhythm of body temperature, heart and respiratory rate in newborn dogs. J Comp Physiol.  180(6):895-904.

5. Sousa, M. 2016. Measuring body temperature: how do different sites compare. Vet Rec 178:190-1.

6. Konietschke, et al. (2014). Comparison of auricular and rectal temperature measurement in normothermic, hypothermic, and hyperthermic dogs,Tierarztl Prax Ausg K Kleintiere Heimtiere. 42(1):13-9.

7. Martin A. Baker, Iain MacDonald (2011). Evaluation of magnetic resonance safety of veterinary radiofrequency identification devices at 1T. Veterinary Radiology & Ultrasound, vol. 52, No.2, pp 161-167.

8. Katherine A. Haifley, Silke Hecht (2012). Functionality of implanted microchips following magnetic resonance imaging. JAVMA Vol 240, No5, March 1,.

9. Independent lab study demonstrating HomeAgain Thermochip is a reliable monitor of temperature, compared to 4 digital thermometers (data on file).

10. Chang Tracy Y. et al. (2007). Cell and Protein Compatibility of Parylene-C surfaces. Langmuir  23, 11718-11725.

11. Wolgemuth Lonny. Parylenes : Advanced Polymers for Medical Devices, As presented at the Medical Plastics 2006 Conference in Copenhagen, Denmark November 29, 2006.

12. Jansen J-A. et al. (1999). Biological and migrational characteristics of transponders implanted into beagle dogs. The Veterinary Record.  145, p329-333.

13. Lawrence, C (2010). Microchipping Update: Overview and update of microchip identification. BSAVA CompanionVol 2010, Issue 3, Mar 2010, p. 4 – 7.

14. VMD Microchip Adverse Event Reporting Scheme Apr14-Dec15 Review. Microchip adverse event reporting scheme 2015 review - GOV.UK (

15. Auclair-Ronzaud, J. et al. (2020). No-contact microchip monitoring of body temperature in yearling horses. Journal of Equine Veterinary Science, 86,p. 102892

16. Kang, H. et al. (2020). The use of percutaneous thermal sensing microchips for body temperature measurements in horses prior to, during and after treadmill exercise. Animals, 10(12), p.2274.

17. Auclair-Ronzaud, J. et al. (2020). No-contact microchip measurements of body temperature and behavioural changes prior to foaling. Theriogenology, 157, pp.399-406.


Please choose one of the following options

New chat

Hi there! How can we help?