Columbus Instruments' Comprehensive Lab Animal Monitoring System (CLAMS) has set the standard for multiple parameter scoring of multiple animals. CLAMS has been in production for a over a decade with thousands of animal stations shipped. Unique to CLAMS is its ability to accurately account for food spillage. While important, some tests require a more traditional animal setting which allows for bedding and the delivery of food that more closely matches a home cage environment. CLAMS-HC is a home cage implementation of CLAMS that maintains the features found in our premiere product. CLAMS-HC is designed to be affixed to any standard animal cage and provides an adaptable test environment with snap-in modules to support a broad array of physiological and behavioral monitoring capabilities. CLAMS-HC provides an alternate housing solution that makes use of standard animal cages that support bedding and maintains the use of established standard animal cage cleaning protocols. CLAMS-HC does not require any modification to your standard animal cage. Special lid assemblies provide all of the required connections to Columbus Instruments' leading Oxymax open circuit indirect calorimeter as well as all CLAMS-HC sub-systems.
CLAMS-HC is the solution if:
minor food spillage is a secondary concern
the employment of bedding is required
use of a standard cage facilitates sanitization
Features / Specifications
Feeding and Drinking Monitor
Automated Food and Water Access
Core Body Temperature and Heart Rate by Telemetry
Body Mass Monitor
Statistical Software CLAX
Columbus Instruments Oxymax system is the leading open circuit indirect calorimeter for lab animal research. Heat is derived by assessment of the exchange of oxygen for carbon dioxide that occurs during the metabolic process. The relationship between the volume of gas consumed (oxygen) and of that produced (carbon dioxide) reveals the energy content of the foodstuff utilized by the subject. This 'calorific value' is then applied to the volume of gases exchanged to compute heat.
Oxymax Sensor Technologies:
Mass flow measurement
Paramagnetic or Zirconia Oxide O2sensing
Push or Pull ventilation
Single of Multiple gas sensors
As an indirect calorimeter, Oxymax relies on accurate measurements of gas concentrations and flow. Flow is measured by a mass thermal transfer technique that yields data formatted in terms normalized to scientific STP (760 mmHg and 0° Centigrade). It is the measurement of mass, not volume, that allows Oxymax to be employed under various atmospheric conditions without the need to account for environmental pressure or temperature.
The measurement of oxygen may be performed by these technologies supported by Oxymax:
Paramagnetic O2 Sensor - [standard speed] Provides full 0-100% range
Zirconia O2 Sensor - [high speed] Provides full 0-100% range and high speed response
Carbon Dioxide - is sensed by single beam non-dispersive IR (NDIR).
The combination of the Zirconia Oxide based oxygen sensor and high speed single beam NDIR carbon dioxide sensing provides a chamber measurement in 45-60 seconds. Standard sensors provide a measurement in two minutes.
Removal of water vapor is accomplished by the employment of materials with hydroscopic properties that isolate the sample gas from the drying media. This prevents the sample gas composition from being altered by interaction with the drying media as well as providing reduced volume within the drying pathway. Reduced volume within the drying pathway improves response time and provides very high accuracy measurements of sample gas composition.Oxymax Experiment Runtime Graph of VO2
Oxymax Experiment Runtime Graph of Respiratory Exchange Ratio (RER)
Oxymax Experiment Graph of RER & Feeding
Oxymax supports both push and pull flow methodologies. Systems may be configured with single or multiple gas sensors. Systems equipped with a single set of gas sensors sequentially scan the chambers with a pneumatic multiplexer. These systems have a dwell time of 45 seconds to 2 minutes before advancing to the next chamber. Higher data through-put is accomplished with an increasing number of gas sensors. Optimal performance is achieved with one set of gas sensors assigned to each animal chamber. In such case, data may be recorded at intervals as short as 10 seconds with all chambers operating in parallel.Activity Monitoring
Multiple Axis Measurement
CLAMS-HC may be configured with single, dual or triple axis detection of animal motion using IR photocell technology. Interruption of a IR beam will accrue one "count" as well as identifying animal position within the respective axis . Coverage in a single plane may be implemented with IR photocells located in the X or XY direction. The height of these beams is such that they intersect the animal midway vertically. Placement of IR photocells at a height above the animal detect rearing or jumping (Z-axis).
CLAMS-HC employs Columbus Instruments Opto-M4 or Opto-M5 Activity Monitor and patented (Pat: #4,337,726) process for the tabulation of activity counts associated with ambulation. The method scores counts as ambulation when the animal traverses the cage, breaking a series of IR beams in sequence. Repeated interruptions of the same IR beam do not incur ambulatory counts. All beam interruptions are scored as Total Activity. Subtraction of Ambulatory counts from the Total count provides counts associated with Stereotopy (grooming, scratching, etc.). Multiple axes serve to provide coordinate data that is employed to assess position and distance traveled.
Activity data is tabulated at two intervals by CLAMS-HC. The first interval is concurrent with the period over which calorimetric measurements are performed. This interval can be lengthy as it is dependent on the number of chambers in a CLAMS-HC configuration and the gas sensors employed. A secondary, shorter, interval provides very high temporally resolved animal activity data. Typical bin times for this process are in the range of 10-30 seconds. High resolution actigrams can be generated from this secondary activity data set.
CLAMS-HC Runtime Activity Screen
Tecniplast model 1264 cage with X Y & Z Axis IR Photocells
Food and Water Consumption
Feeders & Drinkers
Most vivariums house animals in a cage that affords ad libitum access to food suspended in a wire mesh lid. Water is offered by either a simple water bottle or circulating watering system with rocker-type valves. The need to provide a similar method of presentation is preserved in CLAMS-HC.
The animal feeder provides access to food through a grated access plate that simulates the wire lid assemblies found on standard caging. The need to provide diets of differing composition, while minimizing foraging and droppings, is made possible by a series of user replaced screens. These screens are sized to allow food of various compositions from standard lab chow to high-fat diets. Screens are available for powdered foods on a semi-custom basis.
Beneath the feeder is a catch basin that serves to minimize food droppings from falling into the animal cage bedding. The catch basin is integral to the suspended feeder and food caught in the catch basin remains on the suspended element and is not scored as food consumed. Food falling into the catch basin remains available to the animal.
Feeders have sufficient capacity to hold food for a week of unattended delivery. Suspended feeders are low cost and additional feeders can be made at the ready for rapid turn- around between experiment runs. Feeders and sipper tubes are manufactured of stainless steel and can be sanitized by any convenient method.
CLAMS-HC employs standard water bottles with sipper tubes equipped with two ball bearings to assure a drip-free seal. The water bottle as a volume of ~120ml. Other water bottles are supported and it is likely that Columbus Instruments can adapt to your preferred water bottle.
The height of CLAMS-HC feeders and drinkers are user positioned to accommodate animals of varying size. A simple clamp need only be loosened and then re-secured to hold the feeder or drinker at the required height.
All CLAMS-HC feeders can accommodate the wide range of diets employed in today's research. High fat diets are made available to the animal with the same ease as extruded, granular or most powdered food stock. Many liquid diets can be made available to the animal by water bottle and monitored by CLAMS-HC. Consult Columbus Instruments with special dietary requirements.
CLAMS-HC monitors the removal of food and water with a mass resolution of 0.01g. CLAMS-HC employs custom manufactured load cells that are fully temperature compensated to assure stable and reliable operation when operated within an environment with rapid changes in temperature like those applicable to cold challenging an animal. The load cells are also overload protected to assure robust performance.
CLAMS-HC Drinker & Feeder
Bout Detection and Scoring
CLAMS-HC continuously monitors for disturbance of drinkers and feeders caused by animal contact. At the moment of disturbance detection, CLAMS-HC makes an initial, but unconfirmed, entry into a log file to identify the start of a potential feeding or drinking bout. The most recent valid mass reading from the load cell is then recorded. Some time later, the load cell will return to a stable state indicating that the animal has backed away from the drinker or feeder. The moment of restoration of stability is entered into the log file along with current mass reading. CLAMS-HC then compares the difference in the two mass readings to detect liquid or food removal. An indicated loss of mass exceeding a user set threshold, typically -0.01g or -0.02g, validates the bout and the entry remains in the log file. A mass difference not meeting the threshold requirement causes the removal of the entry from the log file and no bout is scored. In this manner, CLAMS-HC provides a full list of validated episodic feeding and drinking activity. During analysis, operators may group episodic bouts into meals by evaluating inter-bout periods. Inter-bout periods shorter than a user-specified time may be chained together to form a meal.
Automated Access to Food and Water
Multiple Drinkers and Feeders
CLAMS supports monitoring multiple drinkers or feeders in a common environment. Such capability might be employed for food preference evaluation. Additionally, allowing or denying access to an assortment of diets of varied composition is valuable in assessing the performance of compounds that alter an animal's ability to utilize certain food substrates.
CLAMS-HC can be equipped with the ability to deny feeder and drinker access by way of a rotating barrier. The barrier mechanism may be operated either manually or automatically by way of a computer controlled actuator. When computer controlled, the barrier is actuated by a pre-set time schedule or by way of a consumption threshold based on mass in accordance with a user specified restriction protocol.
Access Control by Time
Figure 1 is a plot depicting the most basic form of CLAMS-HC feeder access Control. In this example, access to the feeder is granted/denied in a 12 hour period. Access is granted for the first 6 hours and denied in the second 6 hours. The period repeats for the duration of the experiment. The example shows an animal that consumed a total 1.9g of food during period one and a an accumulated total of 7.2g at the conclusion of the second period.
Access Control by Mass
Figure 2 is a plot depicting CLAMS-HC ability to restrict feeder access based on a running tabulation of food consumed. In this example, access to the feeder is granted at the start of the experiment. In the course of ~20 hours, the animal had four feeding episodes. During feeding episode four, access was denied following the crossing of an 8 gram mass limit imposed by the operator. Access was denied for the remainder of the experiment. CLAMS-HC supports the ability to resume feeder access following a user imposed latency.
Access Control by Time & Mass
Food hopper access can be controlled by a combination of the above basic control schemes leads to complex protocols for implementation in a controlled feeding regiment. In the case of the scenario in Figure 3, the operator has imposed a 12 hour period (6 hours granted & 6 hours denied) as well as placing a 4 gram consumption limit on the animal. During the 12-18 hour access period the animal exceeded the 4 gram consumption limit well in advance of the onset of access denial. The result is a total of 5.9 grams of food consumed in 24 hours.
Yoked/Paired Feeding Paradigms
CLAMS-HC supports operator configurations of the drinker and feeder Access Control mechanism that allow complex yoked/paired feeding paradigms. The consumption activity pattern of one animal may be imposed on others for the purpose of caloric intake matching by employing the unique of Access Control configuration screen in CLAMS-HC.
CLAMS-HC TelemetryCLAMS-HC supports the monitoring of body core temperature and heart rate by way of an implanted transmitter. The transmitters are suitable for implantation in mice.
Transmitter physical specifications:
Temperature: 15.5 x 6.5 mm , 1.1 grams
Temperature and Heart Rate: 26 x 6.5mm , 1.5 grams
CLAMS-HC transmitters do not require an internal power source. An external field is generated by an antenna system that, momentarily, charges the transmitter. The transmitter remains powered for a brief period. While powered, the transmitter conveys data back to the antenna and to CLAMS-HC. Following transmission, the transmitter goes dormant while it awaits another charge/transmit cycle. This process occurs once every four seconds in CLAMS-HC.
Temperature and Heart Rate Transmitter
Body Mass Monitoring
CLAMS-HC can be equipped with the ability to intermittently monitor body mass. This option is implemented using the same high quality load cell employed for food and liquid mass monitoring. In this configuration, the animal is provided with an appealing cubby-hole fabricated from a translucent tube. The diminished lighting within the tube offers an environment conducive to nesting. The cubby-hole is supported by a mechanism affixed to the load cell. CLAMS-HC monitors the animal's entry into the cubby-hole and, once settled, the animal's mass is recorded.
Due to the "animal-driven" nature of this measurement method, body mass measurements can not be performed on a fixed schedule.
Body mass cubby
CLAMS-HC with Running Wheel
CLAMS-HC can be equipped with running wheels with rotation monitoring. Running wheels are sized to fit within most standard mouse chambers. CLAMS-HC running wheels measure 94mm diameter (inside diameter) by 35mm wide. A magnet located at the perimeter of the wheel provides a field that is sensed as it passes a detector that, in turn, conveys rotation information to CLAMS-HC.
Running wheels are equipped with a mechanical brake that can be actuated manually or, optionally, by the CLAMS-HC program in accordance with a user specified protocol.
Temperature and Lighting Control
CLAMS-HC systems can be fabricated within a temperature and light controlled enclosure. The temperature within the enclosure may be set within the range of 5° to 40° Centigrade.
Temperature control is implemented by way of either a simple, single set-point thermostat or by way of a programmable "ramp and soak" controller that allows complex temperature profiles to be programmed and called up for repeated use. Temperature uniformity within the enclosure is better than +/-0.25° Centigrade. The enclosure is equipped with upper and lower temperature limits that, if exceeded, shut down the device to prevent endangering the animals.
Lighting control is implemented by way of a simple timer that is user programmable. Lighting is presented with control of both color temperature and level of illumination.
The enclosure is equipped with one, two or three glass panel doors that include light-tight coverings that can be placed over the glass to assure that no ambient light enters the enclosure.
CLAMS-HC systems equipped with a temperature and light controlled enclosure also benefit from an appreciable level of acoustic suppression of ambient sound.
Environmental Enclosure (ENC52) with 12 Stations
Sleep Detection and Analysis
Sleep Detection is a native function of CLAMS-HC program. In application, the operator specifies a set of criteria based on animal activity and time that establishes a threshold below which causes the triggering of the onset of a sleep event. Activity is sensed by the traditional IR beam method. Beam interruptions are scored as "counts". A high count indicates an active subject whereas a low count is indication of a sedentary animal. A count of zero for a prolonged period indicates that the animal is motionless within the spatial resolution of the IR beam monitor. CLAMS-HC Sleep Detection function works in time slices called "epochs". The operator configures the sleep detection algorithm by describing the number of consecutive epochs during which the activity counts are equal to or less than a user defined threshold. CLAMS-HC then flags the episode and tallies the sleep events over a user specified Analysis Window. Continued activity below the threshold infers a continuous sleeping bout.
Sleep Analysis Screen Shot
Sleep Analysis may be performed on single or user grouped animal data. Data tabulated within the user specified Analysis Window is sub-divided into any occurring light and dark sessions. The resulting data from the analysis includes:
Number of Sleep Bouts
Average Sleep Bout Length in Epochs & Time formats
Minimum Sleep Bout Length in Epochs & Time formats
Maximum Sleep Bout Length in Epochs & Time formats
Total Sleep Time in Epochs & Time formats
Percent Time Sleeping within the Analysis Window
Once tabulated, the resulting analysis report may be exported from CLAMS-HC into a CSV (comma separated value) file for additional manipulation by other programs or for presentation.
CLAX data analysis
CLAMS data eXamination Tool
CLAMS-HC can generate copious amounts of data. The CLAMS data eXamination Tool (CLAX) assists in the analysis of this data by presenting it in a meaningful fashion. CLAX allows for organizing animals within an experiment into treatment groups and provides tools for data trimming to remove information collected during animal acclimation. Data samples can also be sub-grouped into data collected during light or dark periods. The resulting trimmed and re-organized data may then be subjected to further analysis by CLAX or other programs.
CLAX allows for the simultaneous analysis of files from several experiments. It's simple to compare experiment results from several dozens of subjects. CLAX can open and analyze files from CLAMS or CLAMS-HC acquisition software version 3.03 or greater.
Visual representation of data in a graphical format can often reveal underlying patterns or relationships that are not easily observed in a table. CLAX provides easily operated tools for the creation of graphs that plot data across time for subjects or groups. Graphs can be made quickly and are highly customizable for purposes of publication or export to other applications.
Graphs can be filtered and smoothed to highlight trends using either a Moving Average or Savitzky-Golay filter. These filters can be applied to assist with reducing short-term deviations that may mask a more meaningful pattern.
Every CLAMS-HC measurement sample can be viewed and exported in a delimited format for use in other programs. Tabular data may be saved in TXT (tab or Semicolon separated) or CSV (comma separated value) formats. Graphs generated by CLAX can be printed or saved in a variety of standard image file formats: BMP, GIF & PNG. These may be easily imported by other program for preparing presentations.