! NEW RESEARCH WORK !
A recent publication
by C. Pitzer, R. Kuner, A. Tappe-Theodor in "Molecular Pain" highlights the merits of using Bioseb's Advanced Dynamic Weight Bearing
: Voluntary and evoked behavioral correlates in neuropathic pain states under different social housing conditions
• 2006 - Incapacitance test, or Static Weight Bearing
: used in nociceptive and analgesia research for assessing pain sensitivity in rodents.
• 2008 - Dynamic Weight Bearing Test
: operator-independent, time-saving, convenient for large amounts of rodents, no animal stress.
• 2011 - Advanced Dynamic Weight Bearing Test
: fast, semi-automatic, operator-independent with advanced video-based software.
Presentation & History
Advanced Dynamic Weight Bearing
Bioseb's Advanced Dynamic Weight Bearing Test is the result of years of R&D based on the principles of early incapacitance instruments, which we evolved into Static Weight Bearing and Dynamic Weight Bearing apparatus, before releasing the brand new Advanced Dynamic Weight Bearing instrument.
Detail with mouse
Weight Bearing of rodents, also named « incapacitance » test, is well known in nociceptive and analgesia research works, and used for studying ostheoarthritis, bone cancer, nerve injuries, analgesic substances, Parkinson, allodynia, etc. Traditional « static » type instruments have been used in the last years for assessing pain sensitivity in rodents (mice and rats).
Those static incapacitance instruments, although showing well correlated results vs. paw pressure vocalization test, calibrated Von Frey filaments, etc. (cf Richebe P, Laulin JP, Simonnet G, Anesthesiology 2005, Pain 2007,...), are highly dependant on the animal's (rat or mouse) position inside a stressful restrainer. This makes these systems time-consuming and difficult to use, particularly when large number of rodents are considered.
In 2008 Bioseb presented the Dynamic Weight Bearing - New Incapacitance Test
, a new test for assessing spontaneous pain in freely moving rodents, which is based on an instrumented-floor cage and a combined video acquisition system. The Dynamic Weight Bearing test, especially suitable for research on Parkinson and allodynia, was a major break-through in the field of research on analgesia: operator-independent, time-saving, convenient for manipulating large amounts of rodents, and induces no stress on the animal (rat or mouse)
The system has been used extensively by many customers from private firms to academic labs since 2008 for various types of research on analgesia and nociception.
The result of this “live” experiment is summarised in a recent publication in Physiology & Behavior
from the team of Dr Sarret Sherbrooke (Canada) and shows that usual ipsilateral/contralateral hindpaw weight ratio measurements overestimate the effect of an analgesic drug
. The Dynamic Weight Bearing
test, which calculates the percentage of weight borne by each paw compared to the total body weight while the animal is able to move freely, offers results that are much closer to reality
. The study performed with mice and rats on three models of pain (inflammatory, cancer, neuropathic) reveals that the forepaw compensation is an important indication in the load pattern redistribution.
The Dynamic Weight Bearing system also offers the possibility of conducting the experiment over a longer observational period (5 minutes) without an operator (thus reducing stress on the animal), and without any habituation period. With these exclusive features, the DWB opens a new and improved generation of instruments for drugs screening and optimization of preclinical models.
The latest version is now a semi-automatic, operator-independent instrument.
Advanced Dynamic Weight Bearing
Screenshot of Bioseb's Software
Performing the same measurements as the original manual Version, the Advanced DWB (Dynamic Weight Bearing) improves two of the turnkey points of the system: the speed of operation and the operator independent factor
. The Advanced DWB allows the user to reduce the most important phase of the process by a factor of 8 to 10, thus the analysis of 1 animal will take 1 to 2 minutes and be operator-independent.
The results encompass a lot of valuable information but will ask for a minimum of manpower and many more animal analysis can be done in the same amount of time than with a manual instrument. The software gives the weight distribution of the animal (rat or mouse), per limb, with additional ratio computations and filtering options.
Analysis and replay can be performed on site or remotely using Bioseb's exclusive software for Dynamic Weight Bearing and Incapacitance tests
. During the analysis and replay, the operator can check and secure each limb recognition for hind and front paws. The weight distribution of the animal (rat or mouse) per limb is then shown in the result window, for each time period with the mean and the variation coefficient.
Versions and setup
• Weight for each paw (g and % total animal weight)
• Weight for grouped front and rear paws (g and %total animal weight)
• Left/Right and Front/Rear weight ratio
• Surface for each paw (mm²)
• Surface for grouped front and rear paws (mm²)
• Variability (standart deviation/mean) for each parameter
• Parameters are given for each posture and as a mean for the whole experiment
• Duration of different postures (4 paws, rearing…) over the whole experiment (s)
• Total time spent on each paw over the whole experiment (s)
Advantages of Bioseb’s dynamic weight bearing system over static incapacitance systems
• Convenient for manipulating large amounts of rodents
• No stress induced on the animal (rat or mouse)
The new version of our Dynamic Weight Bearing Apparatus offers ground-breaking new functionalities:
• Experiment management: define experiment parameters, import a list of subjects and run the total experience. View and analyze subjects on an individual or group basis.
• Possibility to run longer experiments
• Record up to 30 measurements per second (better accuracy on animal positioning)
• Perform detailed analysis on immobility, mobility, or both conditions
• Improved scoring algorithm detecting 80% of the paws
• Special tool to validate video parameters
• Improved tools for scoring, undo/redo option, fusion , etc
• Coming soon: special model for guinea pigs
Applications for your research|
Pain - Nociception/Analgesia
• Bone cancer models
• Neuropathic models
• Inflammation model
• Post surgery models
• Osteo-arthrisis models
• Arthrose models
• Peripheric ischemia
• Cerebrovascular accident models
• Spinal cord injuries recovery process
Other research applications
• Calcaneal tendon disease
• Crucial ligaments disease
All current users of the standard version of Bioseb's Dynamic Weight Bearing are eligible to receive the upgrade which is composed of a software, a high resolution USB camera and a specially designed cover.
The instrument and its camera do not require special lighting conditions : day light conditions. Direct close illumination may be avoided.
The basal feature remains accessible from the new version if necessary especially to train new lab users previous to switch to the semi-automated analysis or simply to validate the results.
The ADVANCED DWB is available in three setups RAT (BIO-DWB-AUTO-R), MICE (BIO-DWB-AUTO-M), COMBINED RAT MICE (BIO-DWB-AUTO-DU).
New Advanced Weight Bearing System for Mouse and Rat, by Bioseb: camera, cover, cage and animal