This work is funded by the Swiss National Foundation (31_138429) and Synapsis Foundation for the support of research on Alzheimer&#8217;s disease.

All the animal procedures are in accordance with the EU Directive 2010/63/EU on the protection of animals used for scientific purposes and are approved by the local Animal Care Committee (Canton of Fribourg, Switzerland).
1. Animal Preparation
<ol>
	<li>Experimental animals
	<ol>
		<li>Perform experiments on adult male wild type and transgenic mice (C57BL/6 background) of 3-5 months of age. The three groups of mice correspond to wild type littermate controls (group A, Jagged1 flox/flox1...

<ol>
	<li>Doty, R. L., Kamath, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+influences+of+age+on+olfaction:+a+review.">The influences of age on olfaction: a review.</a> Cognitive Science. 5, 20 (2014).</li><li>Mesholam, R. I., Moberg, P. J., Mahr, R. N., Doty, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfaction+in+neurodegenerative+disease:+a+meta-analysis+of+olfactory+functioning+in+Alzheimer&#8217;s+and+Parkinson&#8217;s+diseases.">Olfaction in neurodegenerative disease: a meta-analysis of olfactory functioning in Alzheimer&#8217;s and Parkinson&#8217;s diseases.</a> Archives of Neurology. 55 (1), 84-90 (1998).</li><li>Moberg, P. J., 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=Olfactory+Dysfunction+in+Schizophrenia:+A+Qualitative+and+Quantitative+Review.">Olfactory Dysfunction in Schizophrenia: A Qualitative and Quantitative Review.</a> Neuropsychopharmacology. 21 (3), 325-340 (1999).</li><li>Kov&#225;cs, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+olfactory+dysfunction+in+aging+and+neurodegenerative+disorders.">Mechanisms of olfactory dysfunction in aging and neurodegenerative disorders.</a> Ageing Research Reviews. 3 (2), 215-232 (2004).</li><li>Barrios, F. A., 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=Olfaction+and+neurodegeneration+in+HD.">Olfaction and neurodegeneration in HD.</a> Neuroreport. 18 (1), 73-76 (2007).</li><li>Doty, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfaction+in+Parkinson&#8217;s+disease+and+related+disorders.">Olfaction in Parkinson&#8217;s disease and related disorders.</a> Neurobiology of Disease. 46 (3), 527-552 (2012).</li><li>Doty, R. L., Shaman, P., Dann, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+the+University+of+Pennsylvania+Smell+Identification+Test:+a+standardized+microencapsulated+test+of+olfactory+function.">Development of the University of Pennsylvania Smell Identification Test: a standardized microencapsulated test of olfactory function.</a> Physiology &amp; Behavior. 32 (3), 489-502 (1984).</li><li>Devanand, D. p., 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=Olfactory+Deficits+in+Patients+With+Mild+Cognitive+Impairment+Predict+Alzheimer&#8217;s+Disease+at+Follow-Up.">Olfactory Deficits in Patients With Mild Cognitive Impairment Predict Alzheimer&#8217;s Disease at Follow-Up.</a> American Journal of Psychiatry. 157 (9), 1399-1405 (2000).</li><li>Conti, M. Z., 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=Odor+Identification+Deficit+Predicts+Clinical+Conversion+from+Mild+Cognitive+Impairment+to+Dementia+Due+to+Alzheimer&#8217;s+Disease.">Odor Identification Deficit Predicts Clinical Conversion from Mild Cognitive Impairment to Dementia Due to Alzheimer&#8217;s Disease.</a> Archives of Clinical Neuropsychology. 28 (5), 391-399 (2013).</li><li>Keller, A., Vosshall, L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Better+Smelling+Through+Genetics:+Mammalian+Odor+Perception.">Better Smelling Through Genetics: Mammalian Odor Perception.</a> Current opinion in neurobiology. 18 (4), 364-369 (2008).</li><li>Brai, E., 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=Notch1+activity+in+the+olfactory+bulb+is+odour-dependent+and+contributes+to+olfactory+behaviour.">Notch1 activity in the olfactory bulb is odour-dependent and contributes to olfactory behaviour.</a> European Journal of Neuroscience. 40 (10), 3436-3449 (2014).</li><li>Larson, J., Hoffman, J. S., Guidotti, A., Costa, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+discrimination+learning+deficit+in+heterozygous+reeler+mice.">Olfactory discrimination learning deficit in heterozygous reeler mice.</a> Brain Research. 971 (1), 40-46 (2003).</li><li>Alonso, M., 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=Olfactory+Discrimination+Learning+Increases+the+Survival+of+Adult-Born+Neurons+in+the+Olfactory+Bulb.">Olfactory Discrimination Learning Increases the Survival of Adult-Born Neurons in the Olfactory Bulb.</a> The Journal of Neuroscience. 26 (41), 10508-10513 (2006).</li><li>Wesson, D. W., Keller, M., Douhard, Q., Baum, M. J., Bakker, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhanced+urinary+odor+discrimination+in+female+aromatase+knockout+(ArKO)+mice.">Enhanced urinary odor discrimination in female aromatase knockout (ArKO) mice.</a> Hormones and behavior. 49 (5), 580-586 (2006).</li><li>Kobayakawa, K., 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=Innate+versus+learned+odour+processing+in+the+mouse+olfactory+bulb.">Innate versus learned odour processing in the mouse olfactory bulb.</a> Nature. 450 (7169), 503-508 (2007).</li><li>Witt, R. M., Galligan, M. R., Despinoy, J., Segal, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+Behavioral+Testing+in+the+Adult+Mouse.">Olfactory Behavioral Testing in the Adult Mouse.</a> Journal of Visualized Experiments JoVE. (23), (2009).</li><li>Lee, A. W., Emsley, J. G., Brown, R. E., Hagg, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Marked+differences+in+olfactory+sensitivity+and+apparent+speed+of+forebrain+neuroblast+migration+in+three+inbred+strains+of+mice.">Marked differences in olfactory sensitivity and apparent speed of forebrain neuroblast migration in three inbred strains of mice.</a> Neuroscience. 118 (1), 263-270 (2003).</li><li>Page, D. T., 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=Computerized+assessment+of+social+approach+behavior+in+mouse.">Computerized assessment of social approach behavior in mouse.</a> Frontiers in Behavioral Neuroscience. 3, 48 (2009).</li><li>Nyfeler, Y., 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=Jagged1+signals+in+the+postnatal+subventricular+zone+are+required+for+neural+stem+cell+self-renewal.">Jagged1 signals in the postnatal subventricular zone are required for neural stem cell self-renewal.</a> Embo J. 24 (19), 3504-3515 (2005).</li><li>Tong, M. T., Peace, S. T., Cleland, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Properties+and+mechanisms+of+olfactory+learning+and+memory.">Properties and mechanisms of olfactory learning and memory.</a> Frontiers in Behavioral Neuroscience. 8, (2014).</li><li>Corthell, J., Stathopoulos, A., Watson, C., Bertram, R., Trombley, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+Bulb+Monoamine+Concentrations+Vary+with+Time+of+Day.">Olfactory Bulb Monoamine Concentrations Vary with Time of Day.</a> Neuroscience. 247, 234-241 (2013).</li><li>Lehmkuhl, A. M., Dirr, E. R., Fleming, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+assays+for+mouse+models+of+neurodegenerative+disease.">Olfactory assays for mouse models of neurodegenerative disease.</a> Journal of Visualized Experiments: JoVE. (90), e51804 (2014).</li></ol>

There is no conflict of interest.

The tests proposed in this protocol allow to evaluate different aspects of innate olfactory behavior in mice: perception to odors, discrimination between odors versus water and sensitivity to odors. This protocol can be applied to any odor according to the preference and avoidance scale previously shown15. Since the protocol is based on exploratory activity it is important that mice do not display any motor impairment or anxiety which may affect their movement and interfere with olfactory exploration. The test...

Olfaction is one of the most developed and important sensory functions in mammals. Any impairment in olfactory activity may affect food intake, social behavior and, in the worst case scenario, even survival. In humans, olfactory deterioration is age dependent1 and is considered a strong predictor of neurological disorders2&#8211;6. The olfactory identification test developed by the University of Pennsylvania currently represents one of the most used, non-invasive and quantifiable, diagnostic tests which can assess early neurological deficits7 and predict with high probability the progression of dementia8,9.
The accessibility of the olfactory system and the prominence of olfaction in rodents, has sparked an intense line of research addressing the mechanisms underlying olfactory functions10. We have previously shown that loss of function of the signaling receptor Notch1 affects olfactory avoidance11. In this protocol we use mice lacking the signaling ligand, Jagged1, in neurons or glia to study olfactory performance.
Innate olfaction is defined by three parameters as perception, discrimination between odors and olfactory sensitivity4. Olfactory testing in rodents can be done in a variety of ways and some behavioral studies make use of olfactometers, which provide the odor to the animal at a specific vapor concentrations and in a precise time frame12&#8211;14. Nevertheless, this instrumentation is expensive and may be available only in specialized facilities. In our work, we provide a simple, fast and reproducible olfactory testing protocol, which is carried out using volatile scents. The tests described measure perception to an attractant or a repellent odor and evaluate the discrimination between the scent and water11,15,16. Using the same setup, we also can measure the sensitivity to an odor at different concentrations16,17. The post-hoc computer-assisted video processing, inspired by the work of Page and colleagues18, provides unbiased results without the need of experimental blinding and allowing for a single person to carry out the whole experiment.
This protocol is intended to provide a starting point for studying olfactory behavior in mice.

<table border="0" cellpadding="0" cellspacing="0" style="border-collapse:
 collapse;width:192pt">
	<colgroup>
		<col span="4" />
	</colgroup>
	<tbody>
		<tr>
			<td class="xl63">Mouse cage</td>
			<td class="xl64">Italplast (Italy)</td>
			<td class="xl64">1144B</td>
			<td class="xl64">36 cm length x 20.5 cm width x 13.5 cm height</td>
		</tr>
		<tr>
			<td class="xl63">Chipped wood bedding</td>
			<td class="xl64">Abedd (Austria)</td>
			<td class="xl64">LTE E-001</td>
			<td class="xl64">3 cm high</td>
		</tr>
		<tr>
			<td class="xl63">Peanut butter</td>
			<td class="xl64">Migros (Swizterland)</td>
			<td class="xl64">NA</td>
			<td align="right" class="xl65">1:10</td>
		</tr>
		<tr>
			<td class="xl63">2-Methylbutyric</td>
			<td class="xl64">Sigma Aldrich (Switzerland)</td>
			<td class="xl64">W269514</td>
			<td class="xl64">Pure</td>
		</tr>
		<tr>
			<td class="xl63">Female Urine from fertile females of same mouse strain</td>
			<td class="xl64">NA</td>
			<td class="xl64">NA</td>
			<td class="xl64">Dilution series</td>
		</tr>
		<tr>
			<td class="xl63">Camera</td>
			<td class="xl64">Olympus (US)</td>
			<td class="xl64">Camedia C-8080</td>
			<td class="xl64">MOV files</td>
		</tr>
		<tr>
			<td class="xl63">Quicktime for Java (Windows)</td>
			<td class="xl64">Apple (USA)</td>
			<td class="xl64">NA</td>
			<td class="xl64">video plugin for visualizing MOV files</td>
		</tr>
		<tr>
			<td class="xl63">Image J for Windows</td>
			<td class="xl64">NIH (USA)</td>
			<td class="xl64">NA</td>
			<td class="xl64">Video Processing/Analysis</td>
		</tr>
	</tbody>
</table>

simple and computer-assisted olfactory testing for mice

Olfaction is highly conserved among species and is required for reproduction and survival.
In humans, olfaction is also one of the senses that is affected with aging and is a strong predictor of neurodegenerative diseases. Thus, olfaction testing is used as a non-invasive diagnostic method to detect neurological deficits early on. In order to understand the mechanisms underlying olfactory network susceptibility, olfactory research in rodents has gained momentum in the past decade.
Here, we present a very simple, time efficient and reproducible olfactory testing method of innate odor perception and sensitivity in mice without the need of any prior food or water restriction. The tests are performed in a familiar environment to the mice, require only the scents and a 2 min session of odorant exposure. The analysis is performed, post-hoc, using computer-assisted commands on ImageJ and can be, therefore, carried out from start to end by one researcher.
This protocol does not require any special hardware or setup and is indicated for any laboratory interested in testing olfactory perception and sensitivity.

The perception test measures the attraction to peanut butter and avoidance to 2-MB acid. Three groups of mice are tested and the time spent in the &#8220;odor perimeter&#8221; are quantified as compared to water. In the preference test, the control group A displays significant preference to the odor as compared to water (t8 = 2.52, p &#60;0.05). On the other hand, group B does not show any significant attraction to peanut butter and spends more time with water (t6 = 3.22, p &#60;0.05). Thus, it beha...

Watch this Scientific Journal Video about Simple and Computer-assisted Olfactory Testing for Mice at JoVE.com

Simple and Computer-assisted Olfactory Testing for Mice

We present a simple and unbiased olfactory test in mice. With this protocol olfactory discrimination, preference, avoidance and sensitivity to a novel odor as compared to water can be assessed in single behavioral sessions. This method is indicated for a single experimenter and analysis is based on computer-assisted video processing.

Olfaction is highly conserved among species and is required for reproduction and survival.
In humans, olfaction is also one of the senses that is affected ...

simple-and-computer-assisted-olfactory-testing-for-mice

Research

JoVE Journal

Behavior

9.8K visualizações.  University of Fribourg. We present a simple and unbiased olfactory test in mice. With this protocol olfactory discrimination, preference, avoidance and sensitivity to a novel odor as compared to water can be assessed in single behavioral sessions. This method is indicated for a single experimenter and analysis is based on computer-assisted video processing. 