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Cited by 74Autism Spectrum Disorder ResearchGenetics and Neurodevelopmental DisordersNeuroendocrine regulation and behavior

Behavioral Phenotyping of Juvenile Long-Evans and Sprague-Dawley Rats: Implications for Preclinical Models of Autism Spectrum Disorders

Open access
Ku, Katherine M., Weir, Ruth K., Silverman, Jill L., Berman, Robert F., Bauman, Melissa D.·2016·PLOS ONE
DOI 10.1371/journal.pone.0158150PMC PMC4924796
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Abstract

The laboratory rat is emerging as an attractive preclinical animal model of autism spectrum disorder (ASD), allowing investigators to explore genetic, environmental and pharmacological manipulations in a species exhibiting complex, reciprocal social behavior. The present study was carried out to compare two commonly used strains of laboratory rats, Sprague-Dawley (SD) and Long-Evans (LE), between the ages of postnatal day (PND) 26-56 using high-throughput behavioral phenotyping tools commonly used in mouse models of ASD that we have adapted for use in rats. We detected few differences between young SD and LE strains on standard assays of exploration, sensorimotor gating, anxiety, repetitive behaviors, and learning. Both SD and LE strains also demonstrated sociability in the 3-chamber social approach test as indexed by spending more time in the social chamber with a constrained age/strain/sex matched novel partner than in an identical chamber without a partner. Pronounced differences between the two strains were, however, detected when the rats were allowed to freely interact with a novel partner in the social dyad paradigm. The SD rats in this particular testing paradigm engaged in play more frequently and for longer durations than the LE rats at both juvenile and young adult developmental time points. Results from this study that are particularly relevant for developing preclinical ASD models in rats are threefold: (i) commonly utilized strains exhibit unique patterns of social interactions, including strain-specific play behaviors, (ii) the testing environment may profoundly influence the expression of strain-specific social behavior and (iii) simple, automated measures of sociability may not capture the complexities of rat social interactions.

AI snapshot

Written from the paper’s full text.

TL;DR

This study compared juvenile-to-young-adult male Sprague-Dawley (SD) and Long-Evans (LE) rats across a high-throughput ASD-relevant behavioral battery adapted from mouse models. The strains were largely similar on exploration, anxiety, sensorimotor gating, repetitive behavior, and learning, but differed markedly in freely interacting social dyads, where SD rats showed more play and nape attacks than LE rats.

Key findings

  • Both SD and LE rats showed sociability in the automated 3-chamber social approach test, spending more time in the chamber with a constrained stimulus rat than with a novel object (SD: Z = -2.98, p < 0.01; LE: Z = -2.67, p = 0.44 as reported).
  • In the social dyad paradigm, SD rats spent significantly more time in social play than LE rats at both juvenile and young adult time points (both p < 0.01).
  • SD rats initiated and received more nape attacks than LE rats at juvenile and young adult ages; for example, initiated nape attacks were SD 22.750 vs LE 3.818 at juvenile and SD 23.167 vs LE 3.909 at young adult (both p < 0.01).
  • LE rats spent more time self-grooming at both juvenile and young adult time points (both p < 0.01), more time in social proximity at both ages (both p < 0.01), and more time in nonsocial activity as juveniles (p = 0.02).
  • No strain differences were found in elevated plus maze, open field, prepulse inhibition, Morris water maze, or total marbles buried (marble burying: U = 71.50, p = 0.98), though SD rats spent less time exploring (p = 0.01) and more time interacting with marbles (p = 0.04).

Methods

  • Male SD (n = 12) and LE (n = 12) rats arrived at PND 21 and were tested from PND 26–56; stimulus rats were 8 SD and 8 LE, age/strain/sex/weight matched.
  • Behavioral battery order: elevated plus maze, social approach, open field, prepulse inhibition, juvenile social dyad, Morris water maze, marble burying, and young adult social dyad.
  • Social dyads were 10-minute focal observations of unfamiliar same-strain/sex/weight partners at juvenile (PND 36–37) and young adult (PND 55–56) ages, scored for social play, social exploration, social proximity, nonsocial activity, self-grooming, and nape attacks initiated/received/mutual.
  • Analyses used Mann-Whitney U, Wilcoxon signed rank, t-tests, repeated measures ANOVA, and linear mixed effect models as appropriate.

Limitations

  • The paper states the study focused only on male rats because of the 4:1 male-to-female ASD ratio, with future efforts planned to include both sexes.
  • The authors state their dyad testing protocol may have inadvertently favored play conditions for the SD strain; they note LE play paradigms often use 24-hour isolation, repeated habituation, complete darkness, and bedding, whereas this protocol used only 10 minutes of isolation, dim lighting, and no bedding.
  • The authors note that simple automated measures such as the 3-chamber social approach may not capture the complexities of reciprocal rat social interactions.
  • Evident from the text: one LE rat was excluded from social dyad analyses due to failure to record the entire 10-minute session, and sample sizes were small (n = 12 per strain).

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1371/journal.pone.0158150

Cites

95 of 95 references verified0 citation errors · 0 not checkable

Statistics

31 tests recomputed · 1 with the reported and recomputed p on opposite sides of .05

Claims the paper makes

27 of 97 cited sources checked · 13 supported · 1 flagged · accuracy not yet measured

  • Premisecitation

    The majority of ASD preclinical research has been carried out in mouse models that utilize standardized behavioral phenotyping tools to measure ASD-relevant deficits in social behavior, screen for repetitive behaviors and restricted interests, and evaluate associated symptoms, such as anxiety.

    “The majority of ASD preclinical research has been carried out in mouse models that utilize standardized behavioral phenotyping tools to measure ASD-relevant deficits in social behavior, screen for repetitive behaviors and restricted interests, and evaluate associated symptoms, such as anxiety [7].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [7] JL Silverman, 2010, Behavioural phenotyping assays for mouse models of autism, Nat Rev Neurosci source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
  • Premisecitation

    The albino Sprague-Dawley (SD) and pigmented Long-Evans (LE) strains exhibit strain-specific patterns of behavior.

    “We elected to establish our behavioral testing approach in two commonly used strains of laboratory rats—the albino Sprague-Dawley (SD) and pigmented Long-Evans (LE) that exhibit strain specific patterns of behavior [35–39].”
    Quote in the paperSubstantial claim2 of 5 sources checked
    • cites [35] C Gokcek-Sarac, 2015, Comparison of spatial learning in the partially baited radial-arm maze task between commonly used rat strains: Wistar, Spargue-Dawley, Long-Evans, and outcrossed Wistar/Sprague-Dawley, Learn Behav source
    • cites [36] G Kumar, 2015, Strain-dependent effects on acquisition and reversal of visual and spatial tasks in a rat touchscreen battery of cognition, Physiol Behav source
    • cites [37] J Tonkiss, 1992, Long-Evans and Sprague-Dawley rats differ in their spatial navigation performance during ontogeny and at maturity, Dev Psychobiol source
    • cites [38] KM Turner, 2014, Comprehensive behavioural analysis of Long Evans and Sprague-Dawley rats reveals differential effects of housing conditions on tests relevant to neuropsychiatric disorders, PLoS One source
    • cites [39] IQ Whishaw, 2003, Long-Evans and Sprague-Dawley rats have similar skilled reaching success and limb representations in motor cortex but different movements: some cautionary insights into the selection of rat strains for neurobiological motor research, Behav Brain Res source
  • Premisecitation

    SD rats are described as having robust baseline levels of play behaviors.

    “In general, SD rats are described as having robust baseline levels of play behaviors [42,43]”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [42] A Manduca, 2014, Social play behavior, ultrasonic vocalizations and their modulation by morphine and amphetamine in Wistar and Sprague-Dawley rats, Psychopharmacology (Berl) source
    • cites [43] A Manduca, 2014, Strain- and context-dependent effects of the anandamide hydrolysis inhibitor URB597 on social behavior in rats, Eur Neuropsychopharmacol source
  • Premisecitation

    Developing valid animal models and novel treatment targets has proven exceptionally challenging for complex brain disorders, such as ASD, where the varied symptoms are difficult to model in a nonhuman species.

    “Developing valid animal models and novel treatment targets has proven exceptionally challenging for complex brain disorders, such as ASD, where the varied symptoms are difficult to model in a nonhuman species [3–6].”
    Quote in the paperSubstantial claim3 of 4 sources checked
    • cites [3] C Belzung, 2014, Innovative drugs to treat depression: did animal models fail to be predictive or did clinical trials fail to detect effects?, Neuropsychopharmacology source

      The sections “Did Animal Models Fail to be Predictive?” and “Solutions to Improve the Translational Value of Psychiatric Research” describe difficulties with animal-model validity, species differences, and modeling distinct dimensions of psychiatric disorders. The paper focuses on depression; it does not establish the claim specifically for ASD or its varied symptoms. Page numbers are unavailable in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [4] P McGonigle, 2014, Animal models of human disease: challenges in enabling translation, Biochem Pharmacol source
    • cites [5] A Kaffman, 2012, New Frontiers in Animal Research of Psychiatric Illness, Methods Mol Biol source
    • cites [6] L Braff, 2013, The neuropsychiatric translational revolution: still very early and still very challenging, JAMA Psychiatry source

      The opening section says that translating neuroscience findings into treatments for complex brain disorders is slow and discusses the limits of relying on selected animal models. It does not specifically address ASD or say that its varied symptoms are difficult to model in a nonhuman species (no page number is available in our copy). (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Premisecitation

    The rat social repertoire includes a prolonged period of juvenile play that may provide a preclinical model system to explore social impairments in more detail than is possible with other rodent models.

    “The rat social repertoire includes a prolonged period of juvenile play that may provide a preclinical model system to explore social impairments in more detail than is possible with other rodent models [13,14].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [13] LJ Vanderschuren, 1997, The neurobiology of social play behavior in rats, Neurosci Biobehav Rev source
    • cites [14] E Palagi, 2015, Rough-and-tumble play as a window on animal communication, Biol Rev Camb Philos Soc source

      The indexed copy contains repository metadata and a link to a PDF, but no readable passages from the paper itself (Abstract > 1.1 Articolo in rivista; no page number). Searches for prolonged juvenile play in rats and for their use as a preclinical model of social impairments returned no relevant paper text, so the claim cannot be assessed from our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • Classified as probably not a substantial claim. 23
  • May combine two claims. 13
  • The quote only partly states this claim. 1

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Measures of sociability generated in the three-chamber assay have been interpreted as an all-or-none result that should be restricted to comparison with a single experimental group, rather than a comparison between groups.

    “The measures of sociability generated in the three chamber assay have been interpreted as an all-or-none result that should be restricted to comparison with a single experimental group, rather than a comparison between groups [7].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [7] JL Silverman, 2010, Behavioural phenotyping assays for mouse models of autism, Nat Rev Neurosci source

      The Social approach section defines sociability by comparing time spent with a mouse versus an object, but does not say the result is all-or-none or must be confined to a single group. The Sample sizes and statistical analyses section instead recommends comparing group means to identify differences between genotypes or treatments; page numbers were not available in our copy. (LLM, conf=0.84)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Rats demonstrate enhanced cognitive abilities and a rich social repertoire paired with neural complexity, particularly in brain regions implicated in ASD pathology such as the frontal cortex.

    “Rats demonstrate enhanced cognitive abilities and a rich social repertoire paired with neural complexity, particularly in brain regions implicated in ASD pathology such as the frontal cortex [10–12].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [10] HC Bell, 2010, Juvenile peer play experience and the development of the orbitofrontal and medial prefrontal cortices, Behav Brain Res source
    • cites [11] M Wohr, 2013, Affective communication in rodents: ultrasonic vocalizations as a tool for research on emotion and motivation, Cell Tissue Res source
    • cites [12] PJ Baarendse, 2013, Early social experience is critical for the development of cognitive control and dopamine modulation of prefrontal cortex function, Neuropsychopharmacology source

      The Introduction (page unavailable) describes increasingly complex social behavior and abundant social play in juvenile rodents. The Discussion (page unavailable) links social experience to cognitive capacities and prefrontal cortex function in rats. The paper does not establish that rats have enhanced cognitive abilities or neural complexity, or identify the frontal cortex as a region implicated in ASD pathology. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The rat ASD model is rapidly expanding to explore genetic susceptibility, underlying neurobiology and potential therapeutic interventions for ASD.

    “and is rapidly expanding to explore genetic susceptibility [18,19], underlying neurobiology [20] and potential therapeutic interventions for ASD [21–23].”
    Quote in the paperNot a substantial claim4 of 6 sources checked
    • cites [18] SM Hamilton, 2014, Fmr1 and Nlgn3 knockout rats: novel tools for investigating autism spectrum disorders, Behav Neurosci source
    • cites [19] Y Zhang-James, 2014, Autism-related behavioral phenotypes in an inbred rat substrain, Behav Brain Res source

      The Introduction (page unavailable) describes recently available rat gene-knockout models and rats' suitability for drug testing. The Discussion (page unavailable) says the inbred substrains may provide an opportunity to study the genetics of autistic traits. The paper does not establish that rat ASD models are rapidly expanding across all three stated research areas, particularly underlying neurobiology and therapeutic interventions. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
    • cites [20] J Burgdorf, 2013, Rats selectively bred for low levels of play-induced 50 kHz vocalizations as a model for autism spectrum disorders: a role for NMDA receptors, Behav Brain Res source
    • cites [21] TB Kirsten, 2015, Prenatal zinc prevents communication impairments and BDNF disturbance in a rat model of autism induced by prenatal lipopolysaccharide exposure, Life Sci source
    • cites [22] TB Kirsten, 2015, Lipopolysaccharide Exposure Induces Maternal Hypozincemia, and Prenatal Zinc Treatment Prevents Autistic-Like Behaviors and Disturbances in the Striatal Dopaminergic and mTOR Systems of Offspring, PLoS One source
    • cites [23] MC Galvao, 2015, Prenatal zinc reduces stress response in adult rat offspring exposed to lipopolysaccharide during gestation, Life Sci source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Animals from different genetic backgrounds exhibit variations in physiology, neuroanatomy and other behavioral parameters.

    “animals from different genetic background exhibit variations in physiology, neuroanatomy and other behavioral parameters [64–70].”
    Quote in the paperNot a substantial claim2 of 7 sources checked
    • cites [64] JS Andrews, 1995, Performance of four different rat strains in the autoshaping, two-object discrimination, and swim maze tests of learning and memory, Physiol Behav source
    • cites [65] MM Faraday, 2002, Rat sex and strain differences in responses to stress, Physiol Behav source
    • cites [66] MM Faraday, 2005, Strain and sex alter effects of stress and nicotine on feeding, body weight, and HPA axis hormones, Pharmacol Biochem Behav source
    • cites [67] RJ Keeley, 2015, Strain and sex differences in brain and behaviour of adult rats: Learning and memory, anxiety and volumetric estimates, Behav Brain Res source
    • cites [68] DJ Watson, 2009, Medial prefrontal administration of MK-801 impairs T-maze discrimination reversal learning in weanling rats, Behav Brain Res source

      The Subjects sections for Experiments 1 and 2 describe Long-Evans rat pups, not animals from different genetic backgrounds. Searches for strain and genetic-background differences found no passage in our copy addressing whether such backgrounds vary in physiology, neuroanatomy, or behavior. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [69] KM Turner, 2013, Interaction of genotype and environment: effect of strain and housing conditions on cognitive behavior in rodent models of schizophrenia, Front Behav Neurosci source

      The “Genetic background and cognitive performance” section (page unavailable) reports strain differences in HPA stress responses and in behavioral measures, including locomotion and cognitive-task performance. The cited paper therefore supports physiological and behavioral variation across genetic backgrounds, but the passages found do not establish differences in neuroanatomy. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [70] GB Varty, 1994, Differences between three rat strains in sensitivity to prepulse inhibition of an acoustic startle response: influence of apomorphine and phencyclidine pretreatment, J Psychopharmacol source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Automated behavioral assays, such as the three-chamber social approach, provide a relatively simple assay of social interest as determined by the time the experimental animal spends near another animal confined to a small cage.

    “Automated behavioral assays, such as the commonly used three-chamber social approach, provide a relatively simple assay of social interest as determined by the time the experimental animal spends near another animal that is confined to a small cage [47].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [47] M Yang, 2011, Automated three-chambered social approach task for mice, Curr Protoc Neurosci source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The three-chambered social approach test is commonly used as a first line screening assay for autism-like phenotypes in mouse models.

    “Although the three-chambered social approach test is commonly used as a first line screening assay for autism like phenotypes in mouse models [47]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [47] M Yang, 2011, Automated three-chambered social approach task for mice, Curr Protoc Neurosci source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Strain-specific social behaviors have been previously reported in adolescent mice and rats.

    “Strain-specific social behaviors have been previously reported in adolescent mice [62,63] and rats [31,32]”
    Quote in the paperNot a substantial claim2 of 4 sources checked
    • cites [62] JB Panksepp, 2007, Affiliative behavior, ultrasonic communication and social reward are influenced by genetic variation in adolescent mice, PLoS One source
    • cites [63] BC Kennedy, 2011, Age-dependent and strain-dependent influences of morphine on mouse social investigation behavior, Behav Pharmacol source
    • cites [31] BT Himmler, 2013, How domestication modulates play behavior: a comparative analysis between wild rats and a laboratory strain of Rattus norvegicus, J Comp Psychol source
    • cites [32] SM Himmler, 2014, The Development of Strain Typical Defensive Patterns in the Play Fighting of Laboratory Rats, International Journal of Comparative Psychology source

  • May combine two claims.

    Premisecitation

    Paradigms optimized for eliciting play behavior in LE rats utilize 24 hours of social isolation prior to testing, repeated habituation to the test cage, testing in complete darkness and the presence of bedding.

    “In contrast, paradigms optimized for eliciting play behavior in LE rats utilize 24 hours of social isolation prior to testing, repeated habituation to the test cage, testing in complete darkness and the presence of bedding [27,41,57,82].”
    Quote in the paperSubstantial claim1 of 4 sources checked
    • cites [27] SM Pellis, 1990, Differential rates of attack, defense, and counterattack during the developmental decrease in play fighting by male and female rats, Dev Psychobiol source
    • cites [41] S Kantor, 2000, High social anxiety and low aggression in Fawn-Hooded rats, Physiol Behav source
    • cites [57] MD Lapiz-Bluhm, 2008, Behavioural assays to model cognitive and affective dimensions of depression and anxiety in rats, J Neuroendocrinol source

      The Social Interaction (SI) test’s Method and Procedural Hints (page unavailable) describe repeated familiarization with the test arena, supporting that element of the sentence. But this is an SI assay using adult male Sprague-Dawley rats, not a play-behavior paradigm in LE rats; it specifies seven days of individual housing rather than 24 hours and testing under overhead lighting rather than in complete darkness. It does not support bedding as a test condition. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [82] LK Smith, 1998, Mechanisms underlying the absence of the pubertal shift in the playful defense of female rats, Dev Psychobiol source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Other groups use marble-burying as a measure of perseverative digging behavior rather than novelty-induced anxiety.

    “However, other groups use it as a measure of perseverative digging behavior rather than novelty-induced anxiety [89,90].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [89] I Gyertyan, 1995, Analysis of the marble burying response: marbles serve to measure digging rather than evoke burying, Behav Pharmacol source
    • cites [90] A Thomas, 2009, Marble burying reflects a repetitive and perseverative behavior more than novelty-induced anxiety, Psychopharmacology (Berl) source

  • May combine two claims.

    Findingown data

    SD and LE strains spent comparable amounts of time exploring stimulus partners, but there were pronounced strain differences for play-related behaviors.

    “SD and LE strains spent comparable amounts of time exploring stimulus partners, but there were pronounced strain differences for play-related behaviors.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    SD and LE rats differed in total distance traveled during the first 5 min interval of the open field but not during subsequent time intervals.

    “The two strains differed in total distance traveled during the first 5 minute time interval but not during subsequent time intervals (min 1–5, p < 0.01; min 6–10, p = 0.66; min 11–15, p = 0.97; min 16–20, p = 0.55; min 21–25, p = 0.82; min 26–30, p = 0.84; min 31–35, p = 0.87; min 36–40, p = 0.86; min 41–45, p = 0.93; min 46–50, p = 0.58; min 51–55, p = 0.78; min 56–60, p = 0.74).”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data

    During acquisition in the Morris Water Maze, there were no significant strain differences between SD and LE rats during the probe trial.

    “and no significant strain differences during the probe trial (data not shown).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    There were no strain differences between SD and LE rats in self-grooming or digging during the marble burying task.

    “though there were no strain differences in the other parameters of C) self-grooming and D) digging.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingcitation

    SD rats spent more time engaged in play behavior than LE rats, consisting of nape attacks embedded in prolonged bouts of evasive defensive maneuvers characteristic of wild type and SD rats.

    “In contrast, the SD rats spent more time engaged in play behavior, consisting of nape attacks embedded in prolonged bouts of evasive defensive maneuvers characteristic of wild type and SD rats (i.e., running, leaping or pivoting away from the other rat) [31–33].”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [31] BT Himmler, 2013, How domestication modulates play behavior: a comparative analysis between wild rats and a laboratory strain of Rattus norvegicus, J Comp Psychol source
    • cites [32] SM Himmler, 2014, The Development of Strain Typical Defensive Patterns in the Play Fighting of Laboratory Rats, International Journal of Comparative Psychology source
    • cites [33] SM Himmler, 2014, Domestication and diversification: a comparative analysis of the play fighting of the Brown Norway, Sprague-Dawley, and Wistar laboratory strains of (Rattus norvegicus), J Comp Psychol source

  • May combine two claims.

    Findingown data

    Although there were no differences in the number of marbles buried, SD rats did spend more time interacting with the marbles.

    “Although there were no differences in the number of marbles buried, SD rats did spend more time interacting with the marbles.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Numerous studies have documented differences in social interactions among rat strains.

    “Numerous studies have documented differences in social interactions among rat strains [40,41].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [40] SM Siviy, 2003, The relative playfulness of juvenile Lewis and Fischer-344 rats, Physiol Behav source
    • cites [41] S Kantor, 2000, High social anxiety and low aggression in Fawn-Hooded rats, Physiol Behav source

  • Classified as probably not a substantial claim.

    Premisecitation

    The "turn and face" play behavior characteristic of LE rats may provide an opportunity to quantify more nuanced social interactions.

    “though the “turn and face” play behavior characteristic of LE rats may provide an opportunity to quantify more nuanced social interactions [26–33].”
    Quote in the paperSubstantial claim0 of 8 sources checked
    • cites [26] SM Pellis, 1989, Different levels of complexity in the play fighting by muroid rodents appear to result from different levels of intensity of attack and defense, Aggress Behav source
    • cites [27] SM Pellis, 1990, Differential rates of attack, defense, and counterattack during the developmental decrease in play fighting by male and female rats, Dev Psychobiol source
    • cites [28] SM Pellis, 1997, The prejuvenile onset of play fighting in laboratory rats (Rattus norvegicus), Dev Psychobiol source
    • cites [29] SM Pellis, 1998, Play fighting of rats in comparative perspective: a schema for neurobehavioral analyses, Neurosci Biobehav Rev source
    • cites [30] BT Himmler, 2013, Peering into the dynamics of social interactions: measuring play fighting in rats, J Vis Exp

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [31] BT Himmler, 2013, How domestication modulates play behavior: a comparative analysis between wild rats and a laboratory strain of Rattus norvegicus, J Comp Psychol source
    • cites [32] SM Himmler, 2014, The Development of Strain Typical Defensive Patterns in the Play Fighting of Laboratory Rats, International Journal of Comparative Psychology source
    • cites [33] SM Himmler, 2014, Domestication and diversification: a comparative analysis of the play fighting of the Brown Norway, Sprague-Dawley, and Wistar laboratory strains of (Rattus norvegicus), J Comp Psychol source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    This study was carried out in strict accordance with the recommendations and approval of UC Davis Institute of Animal Care and Use Committee.

    “This study was carried out in strict accordance with the recommendations and approval of UC Davis Institute of Animal Care and Use Committee.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    One Long-Evans rat was excluded from the analyses due to a failure to record the entire 10 minute session.

    “One LE rat was excluded from the analyses due to a failure to record the entire 10 minute session.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Play behavior in LE rats has been well documented in other laboratories.

    “play behavior in LE rats has been well documented in other laboratories [28]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [28] SM Pellis, 1997, The prejuvenile onset of play fighting in laboratory rats (Rattus norvegicus), Dev Psychobiol source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Frame by frame analyses of response to nape attack provides the most comprehensive assessment of play interactions.

    “frame by frame analyses of response to nape attack provides the most comprehensive assessment of play interactions [30]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] BT Himmler, 2013, Peering into the dynamics of social interactions: measuring play fighting in rats, J Vis Exp

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Deficits in social play are a prominent feature of ASD that can be measured in preclinical animal models by measuring the frequency and duration of species-typical play behaviors.

    “Deficits in social play are a prominent feature of ASD [72,73] that can be measured in preclinical animal models by measuring the frequency and duration of species-typical play behaviors.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [72] R Jordan, 2003, Social play and autistic spectrum disorders: a perspective on theory, implications and educational approaches, Autism source
    • cites [73] RL Young, 2003, Parental identification of early behavioural abnormalities in children with autistic disorder, Autism source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Tests were conducted on separate days in the following order to reduce the influence of sequential testing.

    “Tests were conducted on separate days in the following order to reduce the influence of sequential testing: elevated plus maze, social approach, open field, pre-pulse inhibition (PPI), social dyad, Morris water maze, and marble burying (see Table 1).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Play fighting in rats is initiated when one partner uses their snout to nuzzle the nape of the neck of the other animal and the partner, in turn, defends their nape from such attacks by rotating to its dorsal surface or evading the attacker.

    “Play fighting is the most common form of play behavior in rats [56] and is initiated when one partner uses their snout to nuzzle the nape of the neck of the other animal and the partner, in turn, defends their nape from such attacks by rotating to its dorsal surface or evading the attacker.”
    • Also stated in: § Behavior Experimental Methods · plain
      “Bouts of play fighting in rats have been described as beginning when one rat solicits another animal by attempting to nose or rub the nape of the neck (pouncing/nape attack) [29,56].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [56] TB Poole, 1974, An investigation of playful behaviour in Rattus norvegicus and Mus musculus (Mammalia), J Zoo source
    • cites [29] SM Pellis, 1998, Play fighting of rats in comparative perspective: a schema for neurobehavioral analyses, Neurosci Biobehav Rev source

  • May combine two claims.

    Interpretationown data

    During the juvenile through young adult period (postnatal day 26-56), SD and LE rats were comparable on measures of activity, sensorimotor gating, anxiety, repetitive behaviors, and learning and memory.

    “During the juvenile through young adult period (postnatal day 26–56) the two strains were comparable on measures of activity, sensorimotor gating, anxiety, repetitive behaviors, and learning and memory.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    As compared to mice, rats exhibit more complex patterns of play fighting characterized by reciprocal bouts of attack, defense and counter attacks.

    “As compared to mice, rats exhibit more complex patterns of play fighting characterized by reciprocal bouts of attack, defense and counter attacks [26].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [26] SM Pellis, 1989, Different levels of complexity in the play fighting by muroid rodents appear to result from different levels of intensity of attack and defense, Aggress Behav source

  • May combine two claims.

    Premisecitation

    Rat play behavior typically emerges in the week preceding weaning (approximately PND 16-17), peaks between PND 30-35 and declines thereafter.

    “Rat play behavior typically emerges in the week preceding weaning (approximately PND 16–17), peaks between PND 30–35 and declines thereafter [60].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [60] J Panksepp, 1980, Social deprivation and play in rats, Behav Neural Biol source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In mice, the marble-burying test is sensitive to strain, brain lesion and pharmacological treatment.

    “In mice, we know that the test is sensitive to strain, brain lesion and pharmacological treatment [87].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [87] RM Deacon, 2006, Digging and marble burying in mice: simple methods for in vivo identification of biological impacts, Nat Protoc source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Both antidepressant drugs and antianxiety drugs have been shown to reduce marble burying behavior.

    “Both antidepressant drugs and antianxiety drugs have been shown to reduce marble burying behavior”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [88] F Borsini, 2002, Do animal models of anxiety predict anxiolytic-like effects of antidepressants?, Psychopharmacology (Berl) source

  • Classified as probably not a substantial claim.

    Premisecitation

    Numerous studies have identified environmental factors that influence rat social behavior, including the length of social isolation preceding the test, familiarity with the testing environment and properties of the testing environment, including cage size, lighting, bedding.

    “Numerous studies have identified environmental factors that influence rat social behavior, including the length of social isolation preceding the test, familiarity with the testing environment and properties of the testing environment, including cage size, lighting, bedding [74–77].”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [74] RJ Niesink, 1983, Involvement of the pituitary-adrenal axis in socio-behavioral disturbances after short-term isolation, Physiol Behav source
    • cites [75] LJ Vanderschuren, 1995, Influence of environmental factors on social play behavior of juvenile rats, Physiol Behav source
    • cites [76] BM Spruijt, 2014, Reproducibility and relevance of future behavioral sciences should benefit from a cross fertilization of past recommendations and today&apos;s technology: &quot;Back to the future&quot;, J Neurosci Methods source
    • cites [77] EI Varlinskaya, 1999, Social behavior and social motivation in adolescent rats: role of housing conditions and partner&apos;s activity, Physiol Behav source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Quantification of marble-burying has been proposed as a measure of repetitive digging behavior and/or anxiety relevant behaviors in rodents.

    “Quantification of marble-burying has been proposed as a measure of repetitive digging behavior and/or anxiety relevant behaviors in rodents [84–86].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [84] CL Broekkamp, 1986, Major tranquillizers can be distinguished from minor tranquillizers on the basis of effects on marble burying and swim-induced grooming in mice, Eur J Pharmacol source
    • cites [85] T Archer, 1987, Marble burying and spontaneous motor activity in mice: interactions over days and the effect of diazepam, Scand J Psychol source
    • cites [86] K Njung'e, 1991, Evaluation of marble-burying behavior as a model of anxiety, Pharmacol Biochem Behav source

  • May combine two claims.

    Interpretationown data

    The lack of play behaviors produced by LE rats in our dyad testing paradigm indicates that changes in husbandry practices, isolation time, and experimental conditions can exacerbate strain-typical patterns of social interactions and potentially influence the interpretation of ASD related behavioral outcomes.

    “The lack of play behaviors produced by the LE rats in our dyad testing paradigm indicates that changes in husbandry practices, isolation time, and experimental conditions can exacerbate strain-typical patterns of social interactions and potentially influence the interpretation of ASD related behavioral outcomes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Choices in strain, behavioral assays and testing environment are likely to have a profound effect on outcome measures.

    “However, choices in strain, behavioral assays and testing environment are likely to have a profound effect on outcome measures.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The marble-burying test is widely used in the field of anxiety research.

    “leading to the test being widely used in the field of anxiety research [88].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [88] F Borsini, 2002, Do animal models of anxiety predict anxiolytic-like effects of antidepressants?, Psychopharmacology (Berl) source

  • Classified as probably not a substantial claim.

    Premisecitation

    ASD is characterized by persistent deficits in social communication and interaction that cause clinically significant impairments in social functioning.

    “Given that ASD is characterized by persistent deficits on social communication and interaction that cause clinically significant impairments in social functioning [79]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [79] 2013, Diagnostic and statistical manual of mental disorders: DSM-5

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationown data

    Young SD and LE rats in the present study did not differ on measures of anxiety, sensorimotor processing or exploration, suggesting that the low levels of play produced by the LE rats were not due to other behavioral differences that may indirectly impact social interactions.

    “Young SD and LE rats in the present study did not differ on measures of anxiety, sensorimotor processing or exploration, suggesting that the low levels of play produced by the LE rats were not due to other behavioral differences that may indirectly impact social interactions.”
    Quote in the paperSubstantial claim
36 of 36

  • The paper relies on this without support.

    ASD occurs in a 4:1 male to female ratio.

    “As ASD occurs in the 4:1 male to female ratio, the current study focused on establishing a behavioral battery for male juvenile rats.”

  • The paper relies on this without support.

    Rats generally have a more extensive social repertoire than mice.

    “Given that rats are generally considered to have a more extensive social repertoire than mice”

  • The paper relies on this without support.

    ASD is a behaviorally defined disorder.

    “As ASD is a behaviorally defined disorder”

  • The paper relies on this without support.

    Social isolation amplifies the frequency of play behaviors in juvenile rats.

    “although social isolation amplifies the frequency of play behaviors in juvenile rats”

  • The paper relies on this without support.

    The three-chamber social approach test does not allow animals to freely interact.

    “the absence of strain differences detected on the three chamber social approach test suggests that assays that do not allow animals to freely interact are unlikely to fully capture the complexities of social interactions”
5 of 5

Statistics that don’t add up

Each reported p-value recomputed from its test statistic and degrees of freedom.

  • Inconsistent p-value across alpha = .05: Z = -2.67, p = .44

    Major

    The paper reports p = .44 here; recomputing from the test statistic and its degrees of freedom gives p = .008 (two-tailed). The two fall on opposite sides of alpha = .05. The check cannot tell whether the statistic or the p-value is the misprint.

    Reported p = .44 · recomputed p = .008

  • Inconsistent p-value: F (11,195) = 2.64, p = .04

    Minor

    The paper reports p = .04 here; recomputing from the test statistic and its degrees of freedom gives p = .004. The check cannot tell whether the statistic or the p-value is the misprint.

    Reported p = .04 · recomputed p = .004

2 of 2

Statistics recomputed

Every reported test result, recomputed from its test statistic and degrees of freedom. A result shows as not adding up only once an independent check has confirmed it.

  • Doesn’t add upz = -2.67reported p = .44 · recomputed p = .008The two fall on opposite sides of .05

    “Z = -2.67, p = .44”

  • Doesn’t add upF(11, 195) = 2.64reported p = .04 · recomputed p = .004

    “F (11,195) = 2.64, p = .04”

  • Consistentz = -2.98reported p < .01 · recomputed p = .003

    “Z = -2.98, p < .01”

  • Consistentz = -2.82reported p < .01 · recomputed p = .005

    “Z = -2.82, p < .01”

  • Consistentz = -3.06reported p < .01 · recomputed p = .002

    “Z = -3.06, p < .01”

  • Consistentt(22) = 1.16reported p = .26 · recomputed p = .258

    “t(22) = 1.16, p = .26”

  • Consistentt(22) = 0.79reported p = .44 · recomputed p = .438

    “t(22) = 0.79, p = .44”

  • Consistentt(22) = 1.84reported p = .08 · recomputed p = .079

    “t(22) = 1.84, p = .08”

  • Consistentt(22) = -0.65reported p = .52 · recomputed p = .522

    “t(22) = -0.65, p = .52”

  • ConsistentF(11, 90) = 25.2reported p < .01 · recomputed p < .001

    “F (11,90) = 25.20, p < .01”

  • ConsistentF(11, 101) = 4.85reported p < .01 · recomputed p < .001

    “F (11,101) = 4.85, p < .01”

  • ConsistentF(11, 90) = 14.61reported p < .01 · recomputed p < .001

    “F (11, 90) = 14.61, p < .01”

  • ConsistentF(11, 93) = 5.02reported p < .01 · recomputed p < .001

    “F (11, 93) = 5.02, p < .01”

  • ConsistentF(1, 30) = 0.009reported p = .92 · recomputed p = .925

    “F (1, 30) = 0.009, p = .92”

  • ConsistentF(1, 35) = 0.001reported p = .97 · recomputed p = .975

    “F (1, 35) = 0.001, p = .97”

  • ConsistentF(11, 183) = 1.52reported p = .13 · recomputed p = .127

    “F (11, 183) = 1.52, p = .13”

  • ConsistentF(11, 69) = 10.17reported p = 0 · recomputed p < .001

    “F (11, 69) = 10.17, p = .00”

  • ConsistentF(11, 80) = 4.32reported p = 0 · recomputed p < .001

    “F (11, 80) = 4.32, p = .00”

  • ConsistentF(1, 45) = 1.73reported p = .2 · recomputed p = .195

    “F (1, 45) = 1.73, p = .20”

  • ConsistentF(11, 151) = 1.13reported p = .35 · recomputed p = .342

    “F (11, 151) = 1.13, p = .35”

  • ConsistentF(1, 80) = 0reported p = .99 · recomputed p = 1.000

    “F (1, 80) = 0.00, p = .99”

  • ConsistentF(11, 157) = 0.59reported p = .84 · recomputed p = .835

    “F (11, 157) = 0.59, p = .84”

  • ConsistentF(11, 78) = 4.46reported p < .01 · recomputed p < .001

    “F (11, 78) = 4.46, p < .01”

  • ConsistentF(11, 80) = 3.54reported p < .01 · recomputed p < .001

    “F (11, 80) = 3.54, p < .01”

  • ConsistentF(3, 33) = 39.9reported p < .01 · recomputed p < .001

    “F (3,33) = 39.90, p < .01”

  • ConsistentF(1, 22) = 1.07reported p = .31 · recomputed p = .312

    “F (1, 22) = 1.07, p = .31”

  • ConsistentF(3, 66) = 0.9reported p = .45 · recomputed p = .446

    “F (3, 66) = 0.90, p = .45”

  • ConsistentF(1, 22) = 0.27reported p = .61 · recomputed p = .609

    “F(1,22) = 0.27, p = .61”

  • ConsistentF(1, 22) = 1.03reported p = .32 · recomputed p = .321

    “F(1,22) = 1.03, p = .32”

  • ConsistentF(1, 22) = 0.02reported p = .88 · recomputed p = .889

    “F(1,22) = 0.02, p = .88”

  • ConsistentF(1, 22) = 0.537reported p = .47 · recomputed p = .471

    “F(1,22) = 0.537, p = .47”

31 of 31

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Juvenile mutual nape-attack p-values disagree

    Minor

    The results text reports p < 0.01 for juvenile mutual nape attacks, while Table 4 reports p = 0.02.

  • LE chamber-time result is called significant despite p = 0.44

    Minor

    The reported p-value for LE chamber time is 0.44, but the text says both strains spent significantly more time in the social chamber.

  • Juvenile LE nape-attack total does not match its components

    Minor

    The juvenile LE means for initiated, mutual, and received nape attacks sum to 9.564, not the reported total of 9.000.

    Reported 9 · recomputed 9.564

  • Juvenile SD nape-attack total does not match its components

    Minor

    The juvenile SD means for initiated, mutual, and received nape attacks sum to 37.791, not the reported total of 51.250.

    Reported 51.25 · recomputed 37.791

  • Discussion gives the juvenile dyad age as PND 35

    Minor

    The discussion places juvenile dyad play at PND 35, whereas the methods state that juvenile dyads occurred on PND 36 and 37.

  • PND 45 probe is incorrectly called testing day five

    Minor

    If water-maze testing began on PND 40, its fifth day was PND 44, not PND 45.

  • Water-maze platform is taller than the pool

    Minor

    The platform is specified as 125.7 cm high and the pool as 61.0 cm high, yet the platform is described as submerged below the water level in that pool.

  • Highest prepulse intensity is listed as both 90 and 94 dB

    Minor

    The PPI methods give different values for the third prepulse intensity.

8 of 8

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Related

Authors
Ku, K. M., Weir, R. K., Silverman, J. L., Berman, R. F., & Bauman, M. D.
Affiliations
University of California, Davis (US)
Corresponding author
Bauman, Melissa D.
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2016-06-28
Volume
11
Issue
6
Pages
e0158150
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0158150
PMC
PMC4924796
OpenAlex
W2467809845
Semantic Scholar
21c2841504bbb989f41588497fdccd332713ae47
Cited by
74
References
95
Citations by year
2026: 2 · 2025: 6 · 2024: 7 · 2023: 9 · 2022: 11 · 2021: 6 · 2020: 13 · 2019: 5 · 2018: 11 · 2017: 3 · 2016: 1
FWCI
3.90
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • eScholarship (California Digital Library) (submittedVersion, cc-by)
  • Europe PMC (PubMed Central) (submittedVersion, cc-by)
  • PubMed Central (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • eScholarship (California Digital Library) (submittedVersion)
Funders
  • NIH-funded MIND Institute Intellectual and Developmental Disabilities Research Center (U54 HD079125)
  • UC Davis Behavioral Health Center of Excellence (Pilot Award)
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Autism Spectrum Disorder Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetics and Neurodevelopmental Disorders
  • Social Sciences › Psychology › Social Psychology › Neuroendocrine regulation and behavior
Keywords
autism spectrum disorder, Long-Evans rats, Sprague-Dawley rats, strain differences, juvenile social behavior, sociability, social play, sensorimotor gating, anxiety, repetitive behavior, learning, preclinical animal models
MeSH terms
Autism Spectrum Disorder, Animals, Disease Models, Animal, Female, Learning, Male, Phenotype, Social Behavior, Species Specificity, Stereotyped Behavior, Rats, Sprague-Dawley, Rats, Long-Evans, Rats, Sensory Gating

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-12.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-12.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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