Name: boldness, aggression, and shoaling assays for zebrafish behavioral syndromes
Uploaded: 2016-08-29T13:00:00
Description: Watch this Scientific Journal Video about Boldness, Aggression, and Shoaling Assays for Zebrafish Behavioral Syndromes at JoVE.com

This work was supported by a Howard Hughes Medical Institute Education Grant and an internal grant from the Saint Joseph's University chapter of Sigma Xi. We would also like to thank the three anonymous reviewers who helped strengthen the protocol and interpretations.

The following methodologies for the housing, care, and study of zebrafish have been approved by the Saint Joseph&#39;s University IACUC.
1. Zebrafish Housing and Care
<ol>
	<li>Obtain the subject zebrafish from a local supplier, or from wild-caught populations. Please note that housing the zebrafish is subject to IACUC guidelines and additional permits are required for housing wild-caught populations.</li>
	<li>Identify and separate zebrafish according to sex. Alternatively, skip this step o...

<ol>
	<li>Huntingford, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relationship+between+anti-predator+behaviour+and+aggression+among+conspecifics+in+the+three-spined+stickleback,+Gasterosteus+aculeatus.">The relationship between anti-predator behaviour and aggression among conspecifics in the three-spined stickleback, Gasterosteus aculeatus.</a> Anim Behav. 24, 245-260 (1976).</li><li>R&#233;ale, D., Reader, S. M., Sol, D., McDougall, P. T., Dingemanse, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrating+animal+temperament+within+ecology+and+evolution.">Integrating animal temperament within ecology and evolution.</a> Biol Rev. 82 (2), 291-318 (2007).</li><li>Sih, A., Bell, A., Johnson, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+syndromes:+an+ecological+and+evolutionary+overview.">Behavioral syndromes: an ecological and evolutionary overview.</a> Trends Ecol Evol. 19 (7), 372-378 (2004).</li><li>Conrad, J. L., Weinersmith, K. L., Brodin, T., Saltz, J. B., Sih, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioural+syndromes+in+fishes:+a+review+with+implications+for+ecology+and+fisheries+management.">Behavioural syndromes in fishes: a review with implications for ecology and fisheries management.</a> J Fish Biol. 78 (2), 395-435 (2011).</li><li>Wolf, M., Weissing, F. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+personalities:+consequences+for+ecology+and+evolution.">Animal personalities: consequences for ecology and evolution.</a> Trends Ecol Evol. 27 (8), 452-461 (2012).</li><li>Langheinrich, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zebrafish:+a+new+model+on+the+pharmaceutical+catwalk.">Zebrafish: a new model on the pharmaceutical catwalk.</a> BioEssays. 25 (9), 904-912 (2003).</li><li>Dai, Y. -. J., Jia, Y. -. F., 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=Zebrafish+as+a+model+system+to+study+toxicology:+Zebrafish+toxicology+monitoring.">Zebrafish as a model system to study toxicology: Zebrafish toxicology monitoring.</a> Environ Toxicol Chem. 33 (1), 11-17 (2014).</li><li>Norton, W., Bally-Cuif, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+zebrafish+as+a+model+organism+for+behavioural+genetics.">Adult zebrafish as a model organism for behavioural genetics.</a> Neuroscience. 11 (1), 90 (2010).</li><li>Gerlai, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zebra+fish:+an+uncharted+behavior+genetic+model.">Zebra fish: an uncharted behavior genetic model.</a> Behav Genet. 33 (5), 461-468 (2003).</li><li>Dzieweczynski, T. L., Campbell, B. A., Marks, J. M., Logan, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+exposure+to+17&#945;-ethinylestradiol+alters+boldness+behavioral+syndrome+in+female+Siamese+fighting+fish.">Acute exposure to 17&#945;-ethinylestradiol alters boldness behavioral syndrome in female Siamese fighting fish.</a> Horm Behav. 66 (4), 577-584 (2014).</li><li>Mikl&#242;si, &. #. 1. 9. 3. ;., Andrew, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Zebrafish+as+a+Model+for+Behavioral+Studies.">The Zebrafish as a Model for Behavioral Studies.</a> Zebrafish. 3 (2), 227-234 (2006).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Zebrafish protocols for neurobehavioral research. , (2012).</li><li>Moretz, J. A., Martins, E. P., Robison, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+syndromes+and+the+evolution+of+correlated+behavior+in+zebrafish.">Behavioral syndromes and the evolution of correlated behavior in zebrafish.</a> Behav Ecol. 18 (3), 556-562 (2007).</li><li>Way, G. P., Kiesel, A. L., Ruhl, N., Snekser, J. L., McRobert, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sex+differences+in+a+shoaling-boldness+behavioral+syndrome,+but+no+link+with+aggression.">Sex differences in a shoaling-boldness behavioral syndrome, but no link with aggression.</a> Behav Process. 113, 7-12 (2015).</li><li>Toms, C. N., Echevarria, D. J., Jouandot, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+methodological+review+of+personality-related+studies+in+fish:+Focus+on+the+shy-bold+axis+of+behavior.">A methodological review of personality-related studies in fish: Focus on the shy-bold axis of behavior.</a> J Comp Psychol. 23, 1-25 (2010).</li><li>Rowland, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+visual+cues+in+fish+behavior:+A+review+of+ethological+techniques.">Studying visual cues in fish behavior: A review of ethological techniques.</a> Environ Biol Fish. 56 (3), 285-305 (1999).</li><li>Way, G. P., Ruhl, N., Snekser, J. L., Kiesel, A. L., McRobert, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Comparison+of+Methodologies+to+Test+Aggression+in+Zebrafish.">A Comparison of Methodologies to Test Aggression in Zebrafish.</a> Zebrafish. 12 (2), 144-151 (2015).</li><li>Moss, S., Tittaferrante, S., 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=Interactions+between+aggression,+boldness+and+shoaling+within+a+brood+of+convict+cichlids+(Amatitlania+nigrofasciatus).">Interactions between aggression, boldness and shoaling within a brood of convict cichlids (Amatitlania nigrofasciatus).</a> Behav Process. 121, 63-69 (2015).</li><li>Ruhl, N., Kiesel, A. L., McRobert, S. P., Snekser, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioural+syndromes+and+shoaling:+connections+between+aggression,+boldness+and+social+behaviour+in+three+different+Danios.">Behavioural syndromes and shoaling: connections between aggression, boldness and social behaviour in three different Danios.</a> Behaviour. 149 (10-12), 1155-1175 (2012).</li><li>Larson, E. T., O'Malley, D. M., Melloni, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aggression+and+vasotocin+are+associated+with+dominant-subordinate+relationships+in+zebrafish.">Aggression and vasotocin are associated with dominant-subordinate relationships in zebrafish.</a> Behav Brain Res. 167 (1), 94-102 (2006).</li><li>McRobert, S., Bradner, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+influence+of+body+coloration+on+shoaling+preferences+in+fish.">The influence of body coloration on shoaling preferences in fish.</a> Anim Behav. 56 (3), 611-615 (1998).</li><li>Ruhl, N., McRobert, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+sex+and+shoal+size+on+shoaling+behaviour+in+Danio+rerio.">The effect of sex and shoal size on shoaling behaviour in Danio rerio.</a> J Fish Biol. 67 (5), 1318-1326 (2005).</li><li>Snekser, J., Ruhl, N., Bauer, K., McRobert, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+influence+of+sex+and+phenotype+on+shoaling+decisions+in+zebrafish.">The influence of sex and phenotype on shoaling decisions in zebrafish.</a> J Comp Psychol. 23, 70-81 (2010).</li><li>Budaev, S. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+Principal+Components+and+Factor+Analysis+in+Animal+Behaviour+Research:+Caveats+and+Guidelines.">Using Principal Components and Factor Analysis in Animal Behaviour Research: Caveats and Guidelines.</a> Ethology. 116 (5), 472-480 (2010).</li><li>Paciorek, T., McRobert, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Daily+variation+in+the+shoaling+behavior+of+zebrafish+Danio+rerio.">Daily variation in the shoaling behavior of zebrafish Danio rerio.</a> Curr Zool. 58 (1), 129-137 (2012).</li><li>Wright, D., Krause, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repeated+measures+of+shoaling+tendency+in+zebrafish+(Danio+rerio)+and+other+small+teleost+fishes.">Repeated measures of shoaling tendency in zebrafish (Danio rerio) and other small teleost fishes.</a> Nat Protoc. 1 (4), 1828-1831 (2006).</li><li>Cachat, J., Stewart, 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=Measuring+behavioral+and+endocrine+responses+to+novelty+stress+in+adult+zebrafish.">Measuring behavioral and endocrine responses to novelty stress in adult zebrafish.</a> Nat Protoc. 5 (11), 1786-1799 (2010).</li><li>Croft, D. P., Krause, J., Couzin, I. D., Pitcher, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=When+fish+shoals+meet:+outcomes+for+evolution+and+fisheries.">When fish shoals meet: outcomes for evolution and fisheries.</a> Fish Fish. 4, 138-146 (2003).</li><li>Brown, M. B., Forsythe, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robust+Tests+for+the+Equality+of+Variances.">Robust Tests for the Equality of Variances.</a> J Am Stat Assoc. 69 (346), (1974).</li><li>Kruskal, W. H., Wallis, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+Ranks+in+One-Criterion+Variance+Analysis.">Use of Ranks in One-Criterion Variance Analysis.</a> J Am Stat Assoc. 47 (260), 583-621 (1952).</li><li>Nelder, J. A., Wedderburn, R. W. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generalized+Linear+Models.">Generalized Linear Models.</a> J Roy Stat Soc A Sta. 135, 370-384 (1972).</li><li>Iman, R. L., Conover, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+distribution-free+approach+to+inducing+rank+correlation+among+input+variables.">A distribution-free approach to inducing rank correlation among input variables.</a> Commun Stat Simulat. 11 (3), 311-334 (1982).</li><li>Fleiss, J. L., Cohen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Equivalence+of+Weighted+Kappa+and+the+Intraclass+Correlation+Coefficient+as+Measures+of+Reliability.">The Equivalence of Weighted Kappa and the Intraclass Correlation Coefficient as Measures of Reliability.</a> Educ Psychol Meas. 33 (3), 613-619 (1973).</li><li>Ruhl, N., McRobert, S. P., Currie, W. J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shoaling+preferences+and+the+effects+of+sex+ratio+on+spawning+and+aggression+in+small+laboratory+populations+of+zebrafish+(Danio+rerio).">Shoaling preferences and the effects of sex ratio on spawning and aggression in small laboratory populations of zebrafish (Danio rerio).</a> Lab Animal. 38 (8), 264-269 (2009).</li><li>Bell, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioural+differences+between+individuals+and+two+populations+of+stickleback+(Gasterosteus+aculeatus).">Behavioural differences between individuals and two populations of stickleback (Gasterosteus aculeatus).</a> J Evolution Biol. 18 (2), 464-473 (2005).</li><li>Wilson, A. D. M., Godin, J. -. G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Boldness+and+behavioral+syndromes+in+the+bluegill+sunfish,+Lepomis+macrochirus.">Boldness and behavioral syndromes in the bluegill sunfish, Lepomis macrochirus.</a> Behav Ecol. 20 (2), 231-237 (2009).</li><li>Brodin, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+syndrome+over+the+boundaries+of+life--carryovers+from+larvae+to+adult+damselfly.">Behavioral syndrome over the boundaries of life--carryovers from larvae to adult damselfly.</a> Behav Ecol. 20 (1), 30-37 (2008).</li><li>Noldus, L. P., Spink, A. J., Tegelenbosch, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EthoVision:+a+versatile+video+tracking+system+for+automation+of+behavioral+experiments.">EthoVision: a versatile video tracking system for automation of behavioral experiments.</a> Behav Res Methods Instrum Comput. 33 (3), 398-414 (2001).</li><li>Cote, J., Fogarty, S., Weinersmith, K., Brodin, T., Sih, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Personality+traits+and+dispersal+tendency+in+the+invasive+mosquitofish+(Gambusia+affinis).">Personality traits and dispersal tendency in the invasive mosquitofish (Gambusia affinis).</a> Proc R Soc B. 277 (1687), 1571-1579 (2010).</li><li>Fraser, D. F., Gilliam, J. F., Daley, M. J., Le, A. N., Skalski, G. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Explaining+leptokurtic+movement+distributions:+intrapopulation+variation+in+boldness+and+exploration.">Explaining leptokurtic movement distributions: intrapopulation variation in boldness and exploration.</a> Am Nat. 158 (2), 124-135 (2001).</li><li>Dingemanse, N. J., Wright, J., Kazem, A. J. N., Thomas, D. K., Hickling, R., Dawnay, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioural+syndromes+differ+predictably+between+12+populations+of+three-spined+stickleback.">Behavioural syndromes differ predictably between 12 populations of three-spined stickleback.</a> J Anim Ecol. 76 (6), 1128-1138 (2007).</li></ol>

The protocol will determine if there are consistent associations in boldness, aggression, and shoaling behaviors in zebrafish. If there are consistent associations in a given population between any of these behaviors, then a behavioral syndrome is present. By studying a population&#39;s natural behavioral syndrome, researchers can have a more complete understanding of its behavioral dynamic, population structure, and possibly evolutionary history3. Furthermore, manipulating the environment that affects these b...

There is a growing body of literature investigating the associations between distinct behaviors within individual animals from a given population. These associations are termed behavioral syndromes, and the measurements typically include boldness, aggression, exploratory behavior, and sociability1-5. Behavioral syndromes are valuable for both direct and indirect reasons. Directly, knowledge of behavioral syndromes can provide a more complete view of evolutionary theory, population structure, and population dynamics3. Indirectly, knowledge regarding behavioral associations may inform fields that quantify behavior such as pharmacology6 , toxicology7, behavioral genetics8,9, and endocrinology10. Because of these direct and indirect benefits, an increased knowledge of behavioral syndromes is especially valuable in commonly used model organisms such as the zebrafish. Studies using zebrafish are found in a variety of disciplines, including the analysis of behavioral syndromes11-13. To advance knowledge in behavioral syndrome research, and because other disciplines also use behavioral measurements for hypothesis testing, reliable and succinct descriptions of behavior are required for valid analyses and interpretations and standardized protocols will facilitate inter-study comparisons within species. Our protocol was developed to measure a boldness-aggression-shoaling behavioral syndrome in a population of lab-reared zebrafish14. However, the basis of the protocol (tracking individual fish, ensuring proper randomization, and appropriate analyses) can be easily modified for a variety of alternative behavioral measures. Additionally, boldness, aggression, or shoaling assays can be run individually for the testing of distinct hypotheses. Therefore, while it is our goal to describe how to conduct a behavioral syndrome study and the protocol for successful individual level behavioral measurement, each facet of this procedure can stand alone.
The literature on behavioral syndromes spans several taxonomic groups, from arthropods to humans4 and, in order to measure a behavioral syndrome, at least two behavioral contexts must be quantified. Unfortunately, there is often little consistency in the assays that are used to quantify the behavioral measurement across the axes of behavior. For example, in fish, boldness may be measured using T-maze assays, open-field assays, or introduction of a novel or foreign stimulus15. Aggression studies in fish might involve dyad interactions, video stimulus assays, or clay model assays12,16,17. Likewise, analysis of shoaling behavior, which typically involves the measurement of shoalmate preference, may be performed in different types of tanks, with different methods to determine association time21-23. In this protocol a specific subset of the overall behavioral assay repertoire is presented. Specifically, this protocol presents a methodology to track individuals through boldness, aggression, and shoaling assays in a way that facilitates comparisons within individuals to determine whether the comparisons are consistent across all individuals within a population. We have performed this protocol with zebrafish and convict cichlids (Amatitlania nigrofasciata) in previous studies14,18, and it will work with any similarly sized freshwater fish.
Boldness assays are conducted in a 1.5 L trapezoidal tank that has a horizontal line delineating equal sized areas in the upper and lower portions of the tank. Quantified behaviors include the number of transitions by the test fish between the upper and lower portion of the tank, the time spent in each portion, the number of darts, and the latency to enter the upper portion. The aggression assay is performed in a 19L rectangular tank that includes a 3 inch x 5 inch mirror inclined at about 22&#176; situated in the lower left corner of the tank19. Quantified behaviors include the total amount of time spent by the target fish interacting with the mirror20, along with specific aggressive indicators &#8211; number of bites, lateral displays, darts between the test fish and its reflection. For these specific indicators, bites are defined as quick lunges toward the mirror with an open mouth, lateral displays are defined as the flaring of lateral, pectoral, anal and dorsal fins in the direction of the mirror, and darts are any erratic movements that are not directed toward the mirror. Lastly, the shoaling assay quantifies the behavior of a test fish in center chamber of a tri-chambered tank. The side chambers of the tank are either empty, or contain a &#34;target shoal&#34; of fish, and the time the test fish spends near each side chamber is measured21-23. A single composite score, referred to as Strength of Shoaling (SoS), is calculated for each individual test fish, specific to the stimuli, and can be used in downstream analyses14. All behaviors are scored by a single viewer, or multiple viewers using free behavioral quantification software known as JWatcher24.
Testing the presence of a behavioral syndrome is primarily a statistical endeavor, and it is advisable to follow the guidelines as presented by Budeav 201025. Specifically, it is recommended to perform a principal components analysis (PCA) on centered and normed data in which the inputs are the vectors of an individual&#39;s behaviors in assays with multiple behavioral measurements (i.e., boldness and aggression). The PCA, performed on a correlation matrix, reduces the dimensionality of the behavioral measurements, and thus extracts the most important knowledge that explains a majority of the variation. The extracted components can then be interpreted based on high factor loadings for the individual behavior of interest and regression scores can be extracted for each individual on the basis of the explanatory components. These regression scores can then be compared to the SoS measurement and other various non-behavioral measurements such as fish size or sex.
This workflow has been implemented in a study of zebrafish behavioral syndromes in which a sex specific behavioral syndrome that exists between boldness and shoaling14 was discovered. In this situation, bolder zebrafish males are more likely to associate with a larger, more aggressive species (D. albolineatus), but this association is lost in females. This workflow was also implemented in a study of juvenile convict cichlid kin (Amatitlania nigrofasciata)18 in which a behavioral syndrome was not discovered, potentially indicating behavioral plasticity of the species. Therefore, the following protocol is presented with a goal of delineating the nature of three specific assays (boldness, aggression, and shoaling) in the framework of studying an individual level behavioral syndrome.

<table border="0" cellpadding="0" cellspacing="0" width="783">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:352px;">Zebrafish Rack System</td>
			<td style="width:224px;">Aquaneering Inc</td>
			<td style="width:119px;">Cat. # ZS550</td>
			<td style="width:88px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Pet Valu Tropical Fish Food, 224.0g</td>
			<td>Pet Valu</td>
			<td>Cat. # 31700</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Premium Grade Brine Shrimp Eggs, 16 oz</td>
			<td>Brine Shrimp Direct</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1.5 L Trapezoidal Tank</td>
			<td>Pentair Aquatic Ecosystems</td>
			<td>Cat. # itsts-a</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">19L rectangular tank</td>
			<td>That Fish Place</td>
			<td align="right">211932</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">76L rectangular tank</td>
			<td>That Fish Place</td>
			<td align="right">212180</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hitachi KP-D20A CCD Camera</td>
			<td>Prescott&#39;s, Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Nikon AF Nikkor 35-105mm f/305~4.5s MACRO lens</td>
			<td>Nikon Corporation</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ArtMinds Square Mirror, Value Pack 3&#34;x3&#34;</td>
			<td>Michaels</td>
			<td>Cat. # 10334162</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Jwatcher</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">SPSS Statistics Base</td>
			<td>IBM</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">R</td>
			<td>The R Foundation</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

boldness, aggression, and shoaling assays for zebrafish behavioral syndromes

A behavioral syndrome exists when specific behaviors interact under different contexts. Zebrafish have been test subjects in recent studies and it is important to standardize protocols to ensure proper analyses and interpretations. In our previous studies, we have measured boldness by monitoring a series of behaviors (time near surface, latency in transitions, number of transitions, and darts) in a 1.5 L trapezoidal tank. Likewise, we quantified aggression by observing bites, lateral displays, darts, and time near an inclined mirror in a rectangular 19 L tank. By dividing a 76 L tank into thirds, we also examined shoaling preferences. The shoaling assay is a highly customizable assay and can be tailored for specific hypotheses. However, protocols for this assay also must be standardized, yet flexible enough for customization. In previous studies, end chambers were either empty, contained 5 or 10 zebrafish, or 5 pearl danios (D. albolineatus). In the following manuscript, we present a detailed protocol and representative data that accompany successful applications of the protocol, which will allow for replication of behavioral syndrome experiments.

Depending on the nature of the study, and specific protocol employed, several distinct results are possible in a behavioral syndromes experiment. The following tables and figures, where indicated, are adapted from our previous study published in the journal Behavioural Processes14 and the journal Zebrafish17. When the proposal (as described above) is carried out in its entirety, two sets of results, &#39;within assay correlations&#39; and &#39;between assay correlati...

Watch this Scientific Journal Video about Boldness, Aggression, and Shoaling Assays for Zebrafish Behavioral Syndromes at JoVE.com

Boldness, Aggression, and Shoaling Assays for Zebrafish Behavioral Syndromes

This manuscript describes the setup, implementation, and analysis of boldness, aggression, and shoaling in zebrafish and testing for the presence of a behavioral syndrome. A standardized approach for behavioral quantification will allow for easier comparison across studies. Modifications to this protocol are possible as each assay can be run individually.

A behavioral syndrome exists when specific behaviors interact under different contexts. Zebrafish have been test subjects in recent studies and it is ...

Research

JoVE Journal

Medicine

Intra-Operative Behavioral Tasks in Awake Humans Undergoing Deep Brain Stimulation Surgery

Deep brain stimulation (DBS) is a surgical procedure that directs chronic, high frequency electrical stimulation to specific targets in the brain through ...

Using Visual and Narrative Methods to Achieve Fair Process in Clinical Care

The Institute of Medicine has targeted patient-centeredness as an important area of quality improvement. A major dimension of patient-centeredness is ...

Biomarkers in an Animal Model for Revealing Neural, Hematologic, and Behavioral Correlates of PTSD

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for ...

Eye Tracking Young Children with Autism

The rise of accessible commercial eye-tracking systems has fueled a rapid increase in their use in psychological and psychiatric research. By providing a ...

Processing of Primary Brain Tumor Tissue for Stem Cell Assays and Flow Sorting

Brain tumors are typically comprised of morphologically diverse cells that express a variety of neural lineage markers. Only a relatively small fraction ...

Screening for Melanoma Modifiers using a Zebrafish Autochthonous Tumor Model

Genomic studies of  human cancers have yielded a wealth of information about genes that are altered  in tumors1,2,3. A challenge arising from these ...

Adaptation of Semiautomated Circulating Tumor Cell (CTC) Assays for Clinical and Preclinical Research Applications

Adaptation of Semiautomated Circulating Tumor Cell CTC Assays for Clinical and Preclinical Research Applications

The majority of cancer-related deaths occur subsequent to the development of metastatic disease. This highly lethal disease stage is associated with the ...

A Novel in vivo Gene Transfer Technique and in vitro Cell Based Assays for the Study of Bone Loss in Musculoskeletal Disorders

A Novel in vivo Gene Transfer Technique and in vitro Cell Based Assays for the Study of Bone Loss in Musculoskeletal Disorders

Differentiation and activation of osteoclasts play a key role in the development of musculoskeletal diseases as these cells are primarily involved in bone ...

A Novel Model of Mild Traumatic Brain Injury for Juvenile Rats

Despite growing evidence that childhood represents a major risk period for mild traumatic brain injury (mTBI) from sports-related concussions, motor ...

Real-time Cytotoxicity Assays in Human Whole Blood

A live cell-based whole blood cytotoxicity assay (WCA) that allows access to temporal information of the overall cell cytotoxicity is developed with ...