The authors wish to thank A.M. for animal identification assistance. This work was supported by grants from the US National Institutes of Health (R01 7 RF1 AG057264 to A.R.L.S. and C.J.C. and R01 NS100023 to A.R.L.S) and the Muscular Dystrophy Association (Basic Research Grant to A.R.L.S., Development Grant to C.J.C.).

All testing conducted with mice was reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) of Duke University. Personnel responsible for testing and scoring must be blinded to animal genotype or experimental condition until gait analysis and scoring of papers has been completed for the entire cohort.
1. Testing material preparation
<ol>
	<li>Conduct testing with a tunnel built from 3 pre-cut clear acrylic panels that are 0.375 inches thick. Assemble tunnel by gluing panels together with a sealant that specifically bonds acrylic and will not emit odors when dried.
	<ol>
		<li>For standard C57BL/6 mice, use the following tunnel measurements: 2.5 in. wide, 3 in. high, and 13 in. long. Mice must be able to comfortably walk through the tunnel and take enough steps (&#62;4) so that gait can be measured.</li>
	</ol>
	</li>
	<li>Construct the goal chamber with pre-cut gray acrylic panels 0.375 inches thick, glued together with the same sealant as used on the tunnel. The interior measurements of the chamber are 4 in. wide, 4 in. long, and 3 in. tall. Match the opening of this chamber to the opening of the tunnel (2.5 in. wide x 3.0 in. tall). Because the mice naturally prefer darkened spaces to well-lit spaces, use material that is opaque and dark in color.</li>
	<li>Use paper for tracking steps that is thick and smooth (watercolor paper works well). Cut individual papers strips to be slightly wider and longer than the width and length of the tunnel. If using the tunnel dimensions described here, cut papers to 15 in. long by 3.5 in. wide.</li>
	<li>Use two contrasting colors (e.g., green and purple) of non-toxic washable water-based paint. Assign one color for hind-limbs, the second one for forelimbs. Mice will lick the remaining paint from their feet after testing, so the selected paint must be completely non-toxic.</li>
	<li>Use two round barrel paintbrushes, one for each paint color (~0.5 cm in diameter, tapered/pointed brush tip).</li>
	<li>Select a ruler with markings down to millimeters, and a caliper with measurements down to 0.1 mm. Pencil is recommended to write on the scoring papers.</li>
	<li>Optional: For animals with high anxiety or low motivation, provide a behavioral incentive in the goal chamber. This can include small amounts of sterilized sunflower seeds (placed in the home cage 2 days prior to testing to allow habituation). On the day of testing, place sunflower seeds inside the goal chamber to encourage mice to walk through without stopping.</li>
</ol>
2. Data collection
<ol>
	<li>If testing is performed in a separate room, acclimate the mice to the new room for 30 minutes and then start the behavioral assays. Additionally, because mice are naturally nocturnal, ensure all mice are fully awake and alert for at least 5 minutes before testing.</li>
	<li>Prepare the testing setup by positioning the tunnel over the paper and marking the paper with mouse ID and testing date. Position the goal chamber at the end of the tunnel, connecting both open ends. Add sunflower seeds at the end of the tunnel (inside the goal chamber) for motivation if needed.</li>
	<li>Remove the mouse to be tested from its cage and grip it firmly by its scruff, making sure to grip the tail to stabilize movement of its hind limbs.</li>
	<li>Paint forepaws so the entire underside of all toes and the center of the foot are fully covered in paint. Repeat this with a contrasting color of paint on its hind paws. Wipe off any paint that the mouse gets on other parts of its body with a clean damp cloth to prevent smudges that may interfere with data collection. 
	NOTE: Mouse handling must be performed by experienced researchers to minimize animal stress.</li>
	<li>Place the mouse at the start of the tunnel and allow it to walk all the way into the goal chamber, and then retrieve the mouse, gently wipe off its feet with a water-dampened cloth, and return it to its home cage.</li>
	<li>Allow paper with footprints to dry fully before scoring. Wipe down the testing area and tunnel with ethanol or an equivalent cleaning solution in between each animal.</li>
</ol>
3. Scoring criteria
<ol>
	<li>Use steps that are consistently spaced with clear, non-smudged footprints for scoring. Figure 1B is a good example of a footprint sequence that can be scored. In order to generate sufficient scoring data, there must be at least 2 consecutive steps from each foot, but 4-6 steps per foot is recommended. Do not include the first and last footprints on the paper, as they are unlikely to represent normal gait because the mouse is changing its walking speed.</li>
	<li>Use stride length, stride width, and toe spread as three different measures of gait that can be analyzed using this method. 
	NOTE: Stride length and width require clear sequential prints where the forefoot region is well defined in paint. Toe spread does not require sequential prints for scoring, only clear prints of the first and last toes on a single foot. However, if a given footprint is not included in measurements of stride length or width, it cannot not be scored for toe spread. All three measures are assessed in centimeters.
	<ol>
		<li>Define stride length as the distance between two sequential footprints created by the same foot (i.e., one stride) (Figure 1A, 1B).
		<ol>
			<li>With a pencil, draw a 2-4 mm circle around the fore-foot region of both forelimb footprints (identified by assigned color above) in a single stride and draw a line between them using a ruler.</li>
			<li>Record the distance between two prints from the middle of each circle (i.e. center of each foot pad) as Right-Fore 1 (RF1) or Left-Fore 1 (LF1).</li>
			<li>Repeat for all steps that can be scored (RF2, LF2, RF3, LF3 and so on).</li>
			<li>Repeat for right and left hind-limb footprints.</li>
			<li>Average all individual recorded stride distances for each limb. For statistical analysis, individual cohort members can be averaged together.</li>
		</ol>
		</li>
		<li>Define stride width as the measure of distance between left and right forelimbs or hind-limbs (Figure 1A, 1B).
		<ol>
			<li>To assess this distance, draw and measure a line from the circled forefoot region of one hind-limb that intersects perpendicularly with the line for stride length on the contralateral hind-limb.</li>
			<li>Repeat this for all hind-limb prints that can be scored, and then average the measurements. The method of calculation for stride width is the same for fore- and hind-limbs.</li>
		</ol>
		</li>
		<li>Define toe spread as the distance between the first and last toes on a single fore- or hind-limb footprint (Figure 1A, 1B).
		<ol>
			<li>Use calipers to measure the distance between the tip of the first toe print and the tip of the last toe print.</li>
			<li>Repeat for all hind-limb prints that can be scored and average the measurements. The method of calculation for toe spread is the same for fore- and hind-limbs.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>If the paper cannot be scored, allow the animal to rest for 10 minutes before trying again.</li>
</ol>

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Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+interference+improves+motor+and+neuropathological+abnormalities+in+a+Huntington's+disease+mouse+model.">RNA interference improves motor and neuropathological abnormalities in a Huntington's disease mouse model.</a> Proceedings of the National Academy of Sciences of the United States of America. 102 (16), 5820-5825 (2005).</li><li>Lin, C. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurological+abnormalities+in+a+knock-in+mouse+model+of+Huntington's+disease.">Neurological abnormalities in a knock-in mouse model of Huntington's disease.</a> Human Molecular Genetics. 10 (2), 137-144 (2001).</li><li>Sopher, B. 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The authors have nothing to disclose.

Using the low-cost gait analysis method described above, we show successful identification of several parameters of gait dysfunction at post-symptomatic ages in the BAC fxAR121 mouse model of SBMA. Decreases in stride length are consistent with prior SBMA studies of mouse models and human patients9. We also show for the first time that there are significant differences in hind-limb toe spread in symptomatic SBMA mice compared to non-transgenic littermate controls. Interestingly, decreases in hind ...

Locomotion requires complex neurological and musculoskeletal coordination, and deficits in a single aspect of motor pathways can produce observable gait abnormalities1,2. Gait analysis is a critical tool for researchers testing mouse models because it provides quantifiable behavioral data on how a given disease, injury, or drug impacts an animal&#8217;s movement3. However, digitized gait analysis requires the purchase of a treadmill, a camera, and associated software, which can be prohibitively expensive for researchers. Gait analysis is often used intermittently to track longitudinal changes in motor function, hence it may be difficult to justify the expenditure if sporadically used4. Although digitized analyses may provide more detailed gait metrics than simple footprint analysis, these more complex measures are not always necessary or relevant for the characterization of a behavioral phenotype5.
Here we present a low-cost manual footprint analysis method as a quick and sensitive alternative to digitized gait analysis programs6,7. Manual footprint analysis has been demonstrated to detect significant gait differences in a multitude of murine disease models4,7,8,9,10,11,12,13,14,15,16,17, and in at least one case, this low-cost method identified changes in gait that were not detected by a common digitized gait analysis program12. The total cost of materials is nominal, and it can be easily adapted to other rodent research models.
While there are many different gait metrics from which data can be drawn, the method we describe focuses on three specific metrics: stride length, stride width (a.k.a. &#8220;track width&#8221;), and toe spread. It is important to note that the parameters to be assessed should be determined on a model-by-model basis. This method of gait analysis is not designed to measure cognitive function, and it is not recommended for studies that require complex biomechanical measurements of gait16.
We present behavioral data from a cohort of pre- and post-symptomatic mice modeling X-linked Spinal and Bulbar Muscular Atrophy (SBMA), a neuromuscular disease characterized by motor neuron degeneration and muscle atrophy. These mice develop progressive deficits in gait that coincide with the onset of other disease-specific phenotypes. This demonstrates the validity and specificity of this method, and confirms that it can reliably discriminate between affected and non-affected animals.
The experimental mice in this study were 2.5 (pre-symptomatic) and 9-month-old (post-symptomatic) BAC fxAR121 transgenic mice on a C57BL/6 background (nexpt=12). This model was generated in our lab and has been fully characterized as a powerful mouse model of SBMA9. Non-transgenic littermates were used as controls (nctrl=8). SBMA is a sex-limited disease which fully manifests in males only, so male mice were used exclusively for this study. During planning stages, researchers must take into account the National Institutes of Health&#8217;s considerations of sex as a biological variable to determine group sizes and composition18.

<table>
	<tbody>
		<tr>
			<td>Caliper</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>must have markings down to 0.1 mm</td>
		</tr>
		<tr>
			<td>Craft Glue</td>
			<td>E6000</td>
			<td>n/a</td>
		</tr>
		<tr>
			<td>Footprint Paint (Tempera Paint)</td>
			<td>Artmind</td>
			<td>n/a</td>
			<td>must be non-toxic</td>
		</tr>
		<tr>
			<td>Round Barrel Paintbrushes</td>
			<td>Symply Simmons</td>
			<td>n/a</td>
			<td>0.5 cm diameter</td>
		</tr>
		<tr>
			<td>Ruler</td>
			<td>n/a</td>
			<td>n/a</td>
			<td>must have markings down to millimeters</td>
		</tr>
		<tr>
			<td>Scoring Paper (Watercolor Pads)</td>
			<td>Canson</td>
			<td>n/a</td>
			<td>cut to size</td>
		</tr>
		<tr>
			<td>Tunnel and Goal Chamber</td>
			<td>Interstate Plastics</td>
			<td>n/a</td>
			<td>cut to size</td>
		</tr>
	</tbody>
</table>

low-cost gait analysis for behavioral phenotyping of mouse models of neuromuscular disease

Measurement of animal locomotion is a common behavioral tool used to describe the phenotype of a given disease, injury, or drug model. The low-cost method of gait analysis demonstrated here is a simple but effective measure of gait abnormalities in murine models. Footprints are analyzed by painting a mouse&#8217;s feet with non-toxic washable paint and allowing the subject to walk through a tunnel on a sheet of paper. The design of the testing tunnel takes advantage of natural mouse behavior and their affinity for small dark places. The stride length, stride width, and toe spread of each mouse is easily measured using a ruler and a pencil. This is a well-established and reliable method, and it generates several metrics that are analogous to digital systems. This approach is sensitive enough to detect changes in stride early in phenotype presentation, and due to its non-invasive approach, it allows for testing of groups across life-span or phenotypic presentation.

With sufficient numbers of animals, this procedure is capable of detecting gait differences between mouse genotypes, within the same strain over time. Figure 1B shows representative traces of footprint images collected in our lab, using a mouse model of X-linked Spinal and Bulbar Muscular Atrophy (SBMA), a neurodegenerative disorder affecting lower motor neurons and skeletal muscle. We have previously reported that male BAC fxAR121 transgenic mice develop significant weight loss, impairments...

Watch this Scientific Journal Video about Low-Cost Gait Analysis for Behavioral Phenotyping of Mouse Models of Neuromuscular Disease at JoVE.com

Low-Cost Gait Analysis for Behavioral Phenotyping of Mouse Models of Neuromuscular Disease

Footprint analysis is a low-cost alternative to digitized gait analysis programs for researchers quantifying movement abnormalities in mice. Because of its speed, simplicity, and longitudinal potential, it is ideal for behavioral phenotyping of mouse models.

Measurement of animal locomotion is a common behavioral tool used to describe the phenotype of a given disease, injury, or drug model. The low-cost method ...

low-cost-gait-analysis-for-behavioral-phenotyping-mouse-models

Research

JoVE Journal

Behavior

16.0K Views.  Duke University School of Medicine. Footprint analysis is a low-cost alternative to digitized gait analysis programs for researchers quantifying movement abnormalities in mice. Because of its speed, simplicity, and longitudinal potential, it is ideal for behavioral phenotyping of mouse models.

Video: Low-Cost Gait Analysis for Behavioral Phenotyping of Mouse Models of Neuromuscular Disease

Assessment of Sensorimotor Function in Mouse Models of Parkinson's Disease

Sensitive and reliable behavioral outcome measures are essential to the evaluation of potential therapeutic treatments in preclinical trials for many neurodegenerative diseases. In Parkinson's disease, sensorimotor tests sensitive to varying degrees of nigrostriatal dysfunction are fundamental for testing the efficacy of potential therapeutics. Reliable and quite elegant sensorimotor measures exist for rats, however many of these tests measure sensorimotor asymmetry within the rat and are not entirely suitable for the newer genetic mouse models of PD. We have put together a battery of sensorimotor tests inspired by the sensitive tests in rats and adapted for mice. The test battery highlighted in this study is chosen for a) its sensitivity in a wide variety of mouse models of PD, b) its ease in implementing into a study, and c) its low expense. These tests have proven useful in characterizing novel genetic mouse models of PD as well as in testing potential disease-modifying therapies.

Assessment of Sensorimotor Function in Mouse Models of Parkinson&#039;s Disease

In Parkinson's disease and movement disorders in general, sensitive and reliable behavioral assays are essential for testing novel potential therapeutics. Here, we describe a manageable battery of sensorimotor tests for mice that are sensitive to varying degrees of injury to the nigrostriatal system and useful for preclinical studies.

Sensitive and  reliable behavioral outcome measures are essential to the evaluation of  potential therapeutic treatments in preclinical trials for many  ...

Nest Building as an Indicator of Health and Welfare in Laboratory Mice

The minimization and alleviation of suffering has moral and scientific implications. In order to mitigate this negative experience one must be able to identify when an animal is actually in distress. Pain, illness, or distress cannot be managed if unrecognized. Evaluation of pain or illness typically involves the measurement of physiologic and behavioral indicators which are either invasive or not suitable for large scale assessment. The observation of nesting behavior shows promise as the basis of a species appropriate cage-side assessment tool for recognizing distress in mice. Here we demonstrate the utility of nest building behavior in laboratory mice as an ethologically relevant indicator of welfare. The methods presented can be successfully used to identify thermal stressors, aggressive cages, sickness, and pain. Observation of nest building behavior in mouse colonies provides a refinement to health and well-being assessment on a day to day basis.

We demonstrate the utility of nest building behavior in laboratory mice as an indicator of welfare. Nest scoring is a sensitive technique that is altered by temperature, illness, and aggression. The time to integrate into nest test (TINT) is a simple cage-side assessment that can detect postoperative pain.

The minimization and alleviation of  suffering has moral and scientific implications. In order to mitigate this  negative experience one must be able to ...

Behavioral Phenotyping of Murine Disease Models with the Integrated Behavioral Station (INBEST)

Due to rapid advances in genetic engineering, small rodents have become the preferred subjects in many disciplines of biomedical research. In studies of chronic CNS disorders, there is an increasing demand for murine models with high validity at the behavioral level. However, multiple pathogenic mechanisms and complex functional deficits often impose challenges to reliably measure and interpret behavior of chronically sick mice. Therefore, the assessment of peripheral pathology and a behavioral profile at several time points using a battery of tests are required. Video-tracking, behavioral spectroscopy, and remote acquisition of physiological measures are emerging technologies that allow for comprehensive, accurate, and unbiased behavioral analysis in a home-base-like setting. This report describes a refined phenotyping protocol, which includes a custom-made monitoring apparatus (Integrated Behavioral Station, INBEST) that focuses on prolonged measurements of basic functional outputs, such as spontaneous activity, food/water intake and motivated behavior in a relatively stress-free environment. Technical and conceptual improvements in INBEST design may further promote reproducibility and standardization of behavioral studies.

Behavioral Phenotyping of Murine Disease Models with the Integrated Behavioral Station INBEST

Prolonged and comprehensive monitoring of mice in a home-cage environment provides a deeper understanding of aberrant behavior in murine models of brain diseases. This paper describes the Integrated Behavioral Station (INBEST) as the key component of contemporary behavioral analysis.

Due to rapid advances in genetic engineering, small rodents have become the preferred subjects in many disciplines of biomedical research. In studies of ...

A Simple and Low-cost Assay for Measuring Ambulation in Mouse Models of Muscular Dystrophy

Measuring functional outcomes in the treatment of muscular dystrophy is an essential aspect of preclinical testing. The assessment of voluntary ambulation in mouse models is a non-invasive and reproducible activity assay that is directly analogous to measures of patient ambulation such as the 6-minute walk test and related mobility scores. Many common methods for testing mouse ambulation speed and distance are based on the open field test, where an animal&#39;s free movement within an arena is measured over time. One major downside to this approach is that commercial software and equipment for high-resolution motion tracking is expensive and may require transferring mice to specialized facilities for testing. Here, we describe a low-cost, video-based system for measuring mouse ambulation that utilizes free and open-source software. Using this protocol, we demonstrate that voluntary ambulation in the dystrophin-null mdx mouse model for Duchenne muscular dystrophy (DMD) is decreased relative to wild-type mouse activity. In mdx mice expressing the utrophin transgene, these activity deficits are not observed and the total distance traveled is indistinguishable from wild-type mice. This method is effective for measuring changes in voluntary ambulation associated with dystrophic pathology, and provides a versatile platform that can be readily adapted to diverse research settings.

This protocol describes a flexible, low-cost system for measuring mouse ambulation in an open field activity assay. We show that a 6-minute ambulation assay based on this system detects a decrease in voluntary movement in mdx mice, and accurately distinguishes improvement in a muscle-specific rescue of these animals.

Measuring functional outcomes in the treatment of muscular dystrophy is an essential aspect of preclinical testing. The assessment of voluntary ambulation ...

Clinical-oriented Three-dimensional Gait Analysis Method for Evaluating Gait Disorder

Three-dimensional gait analysis (3DGA) is shown to be a useful clinical tool for the evaluation of gait abnormality due to movement disorders. However, the use of 3DGA in actual clinics remains uncommon. Possible reasons could include the time-consuming measurement process and difficulties in understanding measurement results, which are often presented using a large number of graphs. Here we present a clinician-friendly 3DGA method developed to facilitate the clinical use of 3DGA. This method consists of simplified preparation and measurement processes that can be performed in a short time period in clinical settings and intuitive results presentation to facilitate clinicians&#39; understanding of results. The quick, simplified measurement procedure is achieved by the use of minimum markers and measurement of patients on a treadmill. To facilitate clinician understanding, results are presented in figures based on the clinicians&#39; perspective. A Lissajous overview picture (LOP), which shows the trajectories of all markers from a holistic viewpoint, is used to facilitate intuitive understanding of gait patterns. Abnormal gait pattern indices, which are based on clinicians&#39; perspectives in gait evaluation and standardized using the data of healthy subjects, are used to evaluate the extent of typical abnormal gait patterns in stroke patients. A graph depicting the analysis of the toe clearance strategy, which depicts how patients rely on normal and compensatory strategies to achieve toe clearance, is also presented. These methods could facilitate implementation of 3DGA in clinical settings and further encourage development of measurement strategies from the clinician&#39;s point of view.

In this study, a clinician-friendly three-dimensional gait analysis method, which was designed to be performed in the rehabilitation clinic, is presented. The method consists of a simplified measurement method and intuitive figures to facilitate clinicians&#39; understanding of the results.

Three-dimensional gait analysis (3DGA) is shown to be a useful clinical tool for the evaluation of gait abnormality due to movement disorders. However, ...

Automated, Long-term Behavioral Assay for Cognitive Functions in Multiple Genetic Models of Alzheimer's Disease, Using IntelliCage

Multiple factors&#8212;such as aging and genes&#8212;are frequently associated with cognitive decline. Genetically modified mouse models of cognitive decline, such as Alzheimer&#39;s disease (AD), have become a promising tool to elucidate the underlying mechanisms and promote the therapeutic advances. An important step is the validation and characterization of expected behavioral abnormality in the models, in the case of AD, cognitive decline. The long-term behavioral investigations of laboratory animals to study the effect of aging demand substantial efforts from researchers. The IntelliCage system is a high-throughput and cost-effective test battery for mice that eliminates the need for daily human handling. Here, we describe how the system is utilized in the long-term phenotyping of a genetic Alzheimer&#39;s disease model, specifically focusing on the cognitive functions. The experiment employs repeated battery of tests that assess spatial learning and executive functions. This cost-effective age-dependent phenotyping allows us to identify the transient and/or permanent effects of genes on various cognitive aspects.

Automated, Long-term Behavioral Assay for Cognitive Functions in Multiple Genetic Models of Alzheimer&#039;s Disease, Using IntelliCage

This paper describes a protocol for cognitive assessments for genetic models of the Alzheimer&#39;s disease using the IntelliCage system, which is a high throughput automated behavioral monitoring system with operant conditioning.

Multiple factors&#8212;such as aging and genes&#8212;are frequently associated with cognitive decline. Genetically modified mouse models of cognitive ...

Low-cost Protocol of Footprint Analysis and Hanging Box Test for Mice Applied the Chronic Restraint Stress

Gait disturbance is frequently observed in patients with movement disorders. In mouse models used for movement disorders, gait analysis is important behavioral test to determine whether the mice mimic the symptoms of patients. Motor deficits are often induced by stress when no spontaneous motor phenotype is observed in the mouse models. Therefore, gait analysis followed by stress loading would be a sensitive method for evaluating the motor phenotype in mouse models. However, researchers face the requirement of an expensive apparatus to obtain quantitative results automatically from gait analysis. For stress, stress loading by simple methods without expensive apparatuses required for electric shock and forced running is desirable. Therefore, we introduce a simple and low-cost protocol consisting of footprint analysis with paper and ink, hanging box test to evaluate motor function, and stress loading defined by restraint with a conical tube. The motor deficits of mice were successfully detected by this protocol.

The low-cost protocol consisting of footprint analysis and hanging box test after restraint stress is useful for evaluating the movement disorders of mouse model.

Gait disturbance is frequently observed in patients with movement disorders. In mouse models used for movement disorders, gait analysis is important ...

Paw-Print Analysis of Contrast-Enhanced Recordings (PrAnCER): A Low-Cost, Open-Access Automated Gait Analysis System for Assessing Motor Deficits

Gait analysis is used to quantify changes in motor function in many rodent models of disease. Despite the importance of assessing gait and motor function in many areas of research, the available commercial options have several limitations such as high cost and lack of accessible, open code. To address these issues, we developed PrAnCER, Paw-Print Analysis of Contrast-Enhanced Recordings, for automated quantification of gait. The contrast-enhanced recordings are produced by using a translucent floor that obscures objects not in contact with the surface, effectively isolating the rat&#8217;s paw prints as it walks. Using these videos, our simple software program reliably measures a variety of spatiotemporal gait parameters. To demonstrate that PrAnCER can accurately detect changes in motor function, we employed a haloperidol model of Parkinson&#8217;s disease (PD). We tested rats at two doses of haloperidol: high dose (0.30 mg/kg) and low dose (0.15 mg/kg). Haloperidol significantly increased stance duration and hind paw contact area in the low dose condition, as might be expected in a PD model. In the high dose condition, we found a similar increase in contact area but also an unexpected increase in stride length. With further research, we found that this increased stride length is consistent with the bracing-escape phenomenon commonly observed at higher doses of haloperidol. Thus, PrAnCER was able to detect both expected and unexpected changes in rodent gait patterns. Additionally, we confirmed that PrAnCER is consistent and accurate when compared with manual scoring of gait parameters.

Paw-Print Analysis of Contrast-Enhanced Recordings PrAnCER: A Low-Cost, Open-Access Automated Gait Analysis System for Assessing Motor Deficits

We describe a novel gait analysis system, Paw-Print Analysis of Contrast-Enhanced Recordings (PrAnCER), an open-access automated system for the quantification of gait characteristics in rats that utilizes a novel semitransparent floor to automatically quantify gait. This system was validated using the haloperidol model of Parkinson&#8217;s Disease.

Gait analysis is used to quantify changes in motor function in many rodent models of disease. Despite the importance of assessing gait and motor function ...

3D Kinematic Gait Analysis for Preclinical Studies in Rodents

The utility of three-dimensional (3D) kinematic motion analysis systems is limited in rodents. Part of the reason for this inadequacy is the use of complex algorithms and mathematical modeling that accompany 3D data collection and analysis procedures. This work provides a simple, user-friendly, step-by-step detailed methodology for 3D kinematic gait analysis during treadmill locomotion in healthy and neurotraumatic rats using a six-camera motion capture system. Also provided are details on 1) calibration of the system in an experimental set-up customized for quadrupedal locomotion, 2) data collection for treadmill locomotion in adult rats using markers positioned on all four limbs, 3) options available for video tracking and processing, and 4) basic 3D kinematic data generation and visualization and quantification of data using the built-in data collection software. Finally, it is suggested that the utility of this motion capture system be expanded to studying a variety of motor behaviors before and after neurotrauma.

Presented here is a protocol to collect and analyze three-dimensional kinematics of quadrupedal locomotion in rodents for preclinical studies.

The utility of three-dimensional (3D) kinematic motion analysis systems is limited in rodents. Part of the reason for this inadequacy is the use of ...

Comparative Analysis of Experimental Methods to Quantify Animal Activity in Caenorhabditis elegans Models of Mitochondrial Disease

Caenorhabditis elegans is widely recognized for its central utility as a translational animal model to efficiently interrogate mechanisms and therapies of diverse human diseases. Worms are particularly well-suited for high-throughput genetic and drug screens to gain deeper insight into therapeutic targets and therapies by exploiting their fast development cycle, large brood size, short lifespan, microscopic transparency, low maintenance costs, robust suite of genomic tools, mutant repositories, and experimental methodologies to interrogate both in vivo and ex vivo physiology. Worm locomotor activity represents a particularly relevant phenotype that is frequently impaired in mitochondrial disease, which is highly heterogeneous in causes and manifestations but collectively shares an impaired capacity to produce cellular energy. While a suite of different methodologies may be used to interrogate worm behavior, these vary greatly in experimental costs, complexity, and utility for genomic or drug high-throughput screens. Here, the relative throughput, advantages, and limitations of 16 different activity analysis methodologies were compared that quantify nematode locomotion, thrashing, pharyngeal pumping, and/or chemotaxis in single worms or worm populations of C. elegans at different stages, ages, and experimental durations. Detailed protocols were demonstrated for two semi-automated methods to quantify nematode locomotor activity that represent novel applications of available software tools, namely, ZebraLab (a medium-throughput approach) and WormScan (a high-throughput approach). Data from applying these methods demonstrated similar degrees of reduced animal activity occurred at the L4 larval stage, and progressed in day 1 adults, in mitochondrial complex I disease (gas-1(fc21)) mutant worms relative to wild-type (N2 Bristol) C. elegans. This data validates the utility for these novel applications of using the ZebraLab or WormScan software tools to quantify worm locomotor activity efficiently and objectively, with variable capacity to support high-throughput drug screening on worm behavior in preclinical animal models of mitochondrial disease.

Comparative Analysis of Experimental Methods to Quantify Animal Activity in Caenorhabditis elegans Models of Mitochondrial Disease

This study presents protocols for two semi-automated locomotor activity analysis approaches in C. elegans complex I disease gas-1(fc21) worms, namely, ZebraLab (a medium-throughput assay) and WormScan (a high-throughput assay) and provide comparative analysis among a wide array of research methods to quantify nematode behavior and integrated neuromuscular function.

Caenorhabditis elegans is widely recognized for its central utility as a translational animal model to efficiently interrogate mechanisms and therapies of ...