Quality Electronics for Wildlife,
and Special Applications
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|Page last updated on Tuesday June 11, 2013|
Historically implants have been used to instrument animals to monitor physiological parameters such as core body temperature, subcutaneous temperature, and heart rate. In early studies there were many concerns over the potential adverse health effects of implant surgery and long term implantation of the system in the body of subject animals. Early reports and observations on several species of mammals, birds, and reptiles implanted for extended time periods indicated that implantation did not seem to adversely affect the behavior of the animal, induce a generalized inflammatory response, or prevent the reproduction of the species that were studied. It was noted that implants were "walled off" soon after implantation. Implants have been successfully removed from animals as long as 7 years after initial implantation surgery. In many instances animals carrying implants have successfully reproduced born and reared young. Although much of this information is anecdotal and has been collected as simply observations during studies specifically addressing other research topics, field reports on the health issues of implanted animals have been extremely favorable. If you choose to use an implant device in a study, Telonics recommends that you review the appropriate literature and consult with the appropriate oversight entities responsible for animal care, health, and treatment at your institution or agency.
Implants though initially used to monitor physiological parameters have more recently been used on numerous species which have a body morphology not suited to wearing external transmitting units. For example, otters simply do not wear collars well and harnessing techniques have been shown to be ineffective and in some cases dangerous to the animal's survival in its environment. Similarly snakes, lizards, and many species of fish are only instrumented using implant technology.
In other applications, the presence of an external device can influence the individual interaction with predators, conspecifics, or even offspring. Therefore in some behavioral studies implant technology is the preferred instrumentation technique because there are no external marks or devices.
Other applications include detection or parturition, the onset of disease processes, or estrous. Radio transmitter implant technology has developed steadily over the years and is today a mature technology for scientific research.
The first step in selecting an implantable transmitting subsystem is determining the appropriate size and weight for the configuration, which includes the transmitting electronics, power supply, and packaging. Often the size and weight of an implant can be greater than with configurations placed on the animal using an external attachment such as a collar. This is especially true with smaller subjects. This is not a recommendation to use the largest implant, but recognition that implants can often be positioned near the center of gravity of the animal, where more weight can be carried and the positioning of the unit is less likely to interfere with normal behavior.
Figure 1. Standard Implantable
Subsystems using Internal Antennas
Click here for
Micro-miniature Implantable Units
|Config.||Dimensions (in, cm)||Unit Weight (g)||Operational Life
@ 60 BPM
Std. Pow (months)
@ 60 BPM
Low Pow (months)
|IMP-100||1.6 x 0.7
4.1 x 1.8
|11||0.7||1.8||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-130||2.1 x 0.75
5.3 x 1.9
|19||4.1||10.5||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-140||4.2 x 0.75
10.7 x 1.9
|40||9.2||23.5||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-150||2.1 x 0.9
5.3 x 2.3
|21||4.1||10.5||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-200||2.4 x 0.9
6.1 x 2.3
|25||7.5||19.2||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-210||2.9 x 0.9
7.4 x 2.3
|38||7.5||19.2||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-325||3.7 x 0.9
9.4 x 2.3
|42||15||38.3||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-400||3.8 x 1.3
9.7 x 3.3
|~95||31.8||81.2||MK8||MS6, MA, MS9, MDC, MS4, MS5|
|IMP-700||6.0 x 1.3
15.2 x 3.3
|~158||63.6||162.4||MK8||MS6, MA, MS9, MDC, MS4, MS5|
The MK8 Transmitter is a single frequency, microprocessor controlled pulsed-CW transmitter, designed for operation in the 140 - 220 MHz frequency range.
|Frequency Range||140 - 220 MHz|
|Frequency Tolerance||±17 ppm max @ 25°C
±25 ppm max -40°lC < Temp < +60°C
(<7ppm typical w/ variation in load impedance - 6:1VSWR)
(<3ppm typical over supply voltage range at room temperature)
|Temperature Range||-40°C to +60 °C (Note: Temperature range is for the transmitter only. The power supply must provide the required peak current and voltage requirements for the transmitter over the expected temperature range.)|
|Shutdown Component||Externally shutdown by presence of a small magnet|
|RF Pulse Width||15 msec standard
Can optionally be configured from 12 - 255 msec
|Pulse Period||Configurable from 200 - 10000 msec (6-300 Bpm)|
|Spurious Emissions||Non-coherent Spurs <-50 dBc|
|Harmonic Suppression||Coherent Spurs <-10 dBc|
|Available Sensors||Motion (Hg switch - activity/mortality) - options MS6, MA
Position (Hg switch - head up/head down) - option MS9
Temperature Triggered Mortality Sensor - option MS5
Temperature Measurement Sensor - MS4
- For 0.4 deg resolution option
±(0.6deg + 0.1deg) = ±0.7degC (±20°C)
±(0.9deg + 0.1deg) = ±1.0degC (±40°C)
- For 0.1 deg resolution option
±(0.15deg + 0.1deg) = ±0.25degC (±10°C)
|Seasonal Timing||8 factory programmable on-off duty cycles - option MDC
Typical timing accuracy of < ± 30 min/yr is reasonable for most applications
Chart reflects known error limits
|FCC Emission Designator||1k00P0N * California Users - The MK8 transmitter exceeds the emission designator requirement of 2k00P0N for operation in California. The MK8's 1k00P0N emission designator is identical to 2k00P0N except that it occupies only half of the 2 kHz bandwidth allowed by the State of California for wildlife tracking.|
|Opt. MDC MK8 Duty Cycles||Transmitters can be programmed to cycle through up to eight sequential time periods or "duty cycles" in order to extend transmitter life. Within each duty cycle, the transmitter can either be "on" or "off". Pulse rates can be uniquely defined for each "on" duty cycle. Each duty cycle can be defined from eight seconds to approximately 50 months in length. Duty Cycle timing begins at the moment the magnet is removed to initialize the transmitter. Upon completion of the last programmed Duty Cycle Period, the transmitter begins again at the first duty cycle.|
|Opt. MA Activity Sensor||Varies the pulse period depending on the relative activity level of the animal. A motion-sensitive switch detects animal movements and the microprocessor monitors changes in the state of the switch (open vs. closed). A user-defined evaluation time is established and the number of switch state changes is recorded by the microprocessor. The maximum number of state changes is limited to one per second by the software. The transmitter pulse period varies between two user-defined pulse periods. One pulse period corresponds to "no activity" and the other corresponds to a user-defined "maximum activity level". A graph supplied with the transmitter correlates activity level and pulse period.|
|Opt. MS4 Temperature Sensor||Monitors body temperature in proximity to the collar on the animal (pulse period varies
with temperature). User may define the desired pulse period vs temperature characteristic of
the transmitter (contact factory for details). Standard temperature resolution is
approximately 0.4°C. Optional high-resolution circuitry provides approximately 0.1° C
The MS4 temperature sensor circuitry provides accurate temperature measurements, even when the transmitter cannot be recovered and recalibrated after period of data collection. This virtually eliminates calibration drifts due to aging and battery voltage changes over time.
|Opt. MS5 Temperature-Triggered Mortality Sensor||This option determines a mortality event in an endothermic animal with a stable body
temperature. Faster (mortality) pulse rate is triggered when body temperature drops below a
user specified temperature.
Note: Pulse rate is returned to original rate if temperature rises back above the specified temperature. Consideration of the ambient temperature is a consideration in selection of the transition threshold. For example, temperature-controlled sensors would probably not be suitable in areas where high ambient temperatures would prevent rapid cooling of body after death. This option is often used in monitoring waterfowl mortality events where motion sensitive mortality sensors may not be applicable (e.g. where the body may continue to be rocked by waves on the surface of a lake). Available in all implant configurations. Please contact the laboratory to discuss implementation of this sensor before ordering.
|Opt. MS6 Mortality-Motion Sensor||Provides "active or alive" or "inactive or dead" pulse period depending on activity
state of the study animal. A motion-sensitive switch is incorporated in the unit to detect
animal movements. The microprocessor continuously monitors the motion switch to determine
when motion occurs. Once per second, the microprocessor increments an "activity counter"
if motion was detected during the preceding one-second time period. This "activity counter"
keeps a running total of the number of times motion was detected over a user-defined
mortality evaluation time (8 sec to 6 days). The active pulse period is maintained as long
as the number of switch closures in the mortality evaluation time is greater than the
mortality threshold. If the number of switch closures falls below the established threshold,
the unit produces the inactive period. A separate resurrection threshold allows the unit to
return to the active pulse period if the number of activity counts during the mortality
evaluation time exceeds the resurrection threshold.
Note: The microprocessor updates the active/inactive pulse period at intervals of 1/16th of the evaluation time. This means that after the "resurrection" threshold criterion is met, there will be a delay of up to 6.25% of the evaluation time before the transmitter reverts to the "active" pulse period. The same is true with the transition between "active" and "inactive" pulse periods. The actual time between cessation of motion and initiation of the "inactive/dead" pulse period can be up to 6.25% longer than the evaluation time.
|Opt. MS9 Tip Switch Sensor||Transmits one of two different pulse rates depending on orientation of the transmitter. Usually designed to switch pulse rates as it passes through an angle of 0° (parallel to horizontal). Other switching angles may be selected with some configurations (factory set within 10°).** Typical uses include monitoring "head up" and "head down" positions.|
The information below is provided for individuals who are still deploying these older systems. Some of the system information or limitations, information on frequency allocation or usage, and/or comments made on "state of the art" may be time sensitive or even outdated. Please contact Telonics if you have any questions about the information provided in this section.
Telonics still supports and refurbishes the following products but no longer sells them new:
Figure 3. Micro-miniature
Click here for Standard Implantable Subsystems
Micro-miniature Implant Subsystems allow the instrumentation of smaller species of animals. The configurations are based on our CHP transmitter. To minimize the size of these configurations very small batteries are used. The smaller battery system limits the operational life of the configuration and also limits the radio frequency (RF) power that can be transmitted by the unit. The CHP electronics are matched to these small battery systems to avoid damaging the batteries yet provide as much range performance as is possible from the configuration. In order to further maximize range of these configurations, they are made with highly flexible external antennas that increase the radiated power. This common configuration is often used in fish and snake applications. Whenever this option is utilized, the implant is internally cast with a polymer and coated in physiological wax to minimize moisture penetration. However, this design is only water resistant - and the penetration of the wax coating by the antenna provides a potential moisture path that ultimately allows, in the long term, penetration of body fluids. The time-frame to moisture penetration is related to the type of external antenna structure selected as well as the flexation and strain placed on the antenna in the body. This technology is best suited to studies 3 to 6 months in duration.
|Config||Dimensions (in, cm)||Unit Weight (g)||Transmitter Electronics||Operational Life @ 60BPM (months)||Operational Life @ 35BPM (months)||Conventional Sensor Options|
|IMP-CHP-5P||1.44 x 0.62 x 0.37
3.66 x 1.57 x 0.94
|6.8||CHP||8.5||13.6||conventional S2 temp|
|IMP-CHP-6P||1.0 x 0.62 x 0.37
2.54 x 1.57 x 0.94
|3.7||CHP||4.2||6.8||conventional S2 temp|
|IMP-CHP-7P||0.83 x 0.45 x 0.37
2.11 x 1.14 x 0.94
|2.2||CHP||1.6||2.7||conventional S2 temp|
|IMP-CHP-8P||0.90 x 0.42 x 0.25
2.29 x 1.07 x 0.64
|1.2||CHP||0.7||1.1||conventional S2 temp|
**Note: The CHP micro miniature transmitter is designed for use with a small battery system. The power output is matched to the power provided by the small battery. Therefore the standard power for an IMP/CHP is much lower than the standards power for a MK8 or MK9 subsystem. This is true of micro miniature transmitter technology in general and throughout the industry.
OPT. S2 Temperature Sensor. Sensor provides pulse rate which varies according to temperature within the transmitting subsystem. User specifies desired pulse rate at anticipated median temperature and approximate range of temperatures to be monitored. Pulse rate increases at higher temperatures and decreases at lower temperatures.
1. Most Telonics implantable telemetry transmitting subsystems utilize an internal transmitting
antenna structure. The structure is contained inside the packaging of the implant. This type of
antenna can be tuned to either air or the dielectric of the body. The tuning choice will affect
where (in air or in the body) the maximum range performance will be achieved. If the unit is tuned
to air, the unit's best performance will be achieved when air surrounds the implant. If the implant
antenna is tuned to the dialectic of the body, the best performance from the implant will be
achieved when the implant is actually inside the body cavity. Note: When testing, it is necessary
to place the implant in the medium in which it will be expected to operate. This is particularly
true when trying to obtain more accurate range performance test data.
For extremely large bodied animals (over 100 pounds), it should be noted that the large mass reduces the effective radiated power of the implant, thereby reducing the range performance of the system. When implanting small terrestrial mammals, the implant is often carried only a few inches off the surface of the earth and thus the range is reduced because line-of-sight range is also reduced under these conditions.
2. Cold method sterilization should be utilized when sterilizing units prior to implantation. The physiological wax can melt with hot method sterilization techniques compromising the units' moisture repelling properties. Also note, units should be stored in a cool environment (such as a cooler) during transportation in vehicles, or kept in a cool environment during periods of storage.