Play like me: Similarity in playfulness promotes social play

Social play is associated with the experience of positive emotions in higher vertebrates and may be used as a measure of animal welfare. Altering motivation to play (e.g., through short-term social isolation) can temporarily affect play levels between familiar individuals, a process which may involve emotional contagion. This study investigated how forming groups based on known differences in the personality trait “playfulness” (i.e., the longer-term propensity of an individual to actively play from adolescence to early adulthood) affects social play. Seventy-six adolescent male Lister Hooded rats underwent a Play-in-Pairs test assessing their playfulness, ranked as high (H), intermediate (I) or low (L). At seven weeks of age, rats were resorted into homogenous groups of similar (LLL, III, HHH), or heterogeneous groups of dissimilar (HII, LII) playfulness. Social play was scored in the home cage at Weeks 8, 10, 12 of age. A second Play-in-Pairs test was performed (Week 11) to assess consistency of playfulness. A Social Preference test investigated whether I rats in heterogeneous groups preferred proximity with I, H or L cage mates. It was found that heterogeneous groups played less than homogeneous ones at adolescence (8 weeks of age), while play levels at early adulthood (Weeks 10 and 12) did not differ between groups. Play in the homogeneous groups decreased with age as expected, while it did not change over time in the heterogeneous groups, which did not compensate for the lower play levels shown at adolescence. Play-in-Pairs scores before and after resorting were mildly correlated, indicating some level of consistency over time despite the resorting procedure. In the Social Preference test, subjects did not prefer one playfulness level over another. We conclude that a mismatch in playfulness may negatively affect social play development, and thus the welfare, of rats. Groups made of animals with similar playfulness, even those initially scoring relatively low in this trait, seemed to be more successful in establishing play relationships during adolescence

Antibody dynamics and spontaneous viral clearance in patients with acute hepatitis C infection in Rio de Janeiro, Brazil

Submitted by Sandra Infurna ([email protected]) on 2017-01-18T10:31:05Z No. of bitstreams: 1 clara_yoshida_etal_IOC_2011.pdf: 146042 bytes, checksum: 8ec889224534b76d755828a99d0660c2 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2017-01-18T10:59:52Z (GMT) No. of bitstreams: 1 clara_yoshida_etal_IOC_2011.pdf: 146042 bytes, checksum: 8ec889224534b76d755828a99d0660c2 (MD5)Made available in DSpace on 2017-01-18T10:59:52Z (GMT). No. of bitstreams: 1 clara_yoshida_etal_IOC_2011.pdf: 146042 bytes, checksum: 8ec889224534b76d755828a99d0660c2 (MD5) Previous issue date: 2011Innsbruck Medical University. Department of Medical Statistics, Informatics and Health Economics. Innsbruck, Austria.Harvard Medical School. Boston, MA, USA / Massachussets General Hospital. Division of Infectious Diseases. Boston, MA, USA.Harvard Medical School. Boston, MA, USA / Massachussets General Hospital. Gastrointestinal Unit. Boston, MA, USA.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil.Laboratório Central de Saúde Pública Noel Nutels. Divisão de Hepatites. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil / Universidade Federal do Estado do Rio de Janeiro. Hospital Universitário Gaffrée Guinle. Unidade de Hepatologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Desenvolvimento Tecnológico em Virologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil.Universitätsklinikum Eppendorf. Medizinische Klinik I. Hamburg, Germany.Fondation Merieux. Emerging Pathogens Laboratory. Lyon, France.University of Innsbruck. Institute of Statistics. Innsbruck, Austria.National Institute on Aging. Gerontology Research Center. Baltimore, USA.Innsbruck Medical University. Department of Medical Statistics, Informatics and Health Economics. Innsbruck, Austria.Innsbruck Medical University. Department of Medical Statistics, Informatics and Health Economics. Innsbruck, Austria.Innsbruck Medical University. Department of Medical Statistics, Informatics and Health Economics. Innsbruck, Austria.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hepatites Virais. Rio de Janeiro, RJ. Brasil.Background: The anti-HCV antibody response has not been well characterized during the early phase of HCV infection and little is known about its relationship to the clinical course during this period. Methods: We analyzed serial anti-HCV antibodies longitudinally obtained from a prospective cohort of 65 patients with acute HCV infection by using a microparticle enzyme immunoassay AxSYM HCV 3.0 (Abbott Diagnostics) during the first 12 months from HCV acquisition in Rio de Janeiro, Brazil. Spontaneous viral clearance (SVC) was defined as undetectable HCV RNA in serum, in the absence of treatment, for three consecutive HCV PCR tests within 12-months of follow-up. Results: Baseline antibody values were similar among patient groups with self-limiting HCV evolution (n = 34) and persistent viremia (n = 31) [median (interquartile range) signal/cut-off ratio (s/co) 78.7 (60.7-93.8) vs. 93.9 (67.8- 111.9), p = 0.26]. During 12-months follow-up, patients with acute spontaneous resolving HCV infection showed significantly lower serial antibody response in comparison to individuals progressing to chronic infection [median (interquartile range) s/co 62.7 (35.2-85.0) vs. 98.4 (70.4-127.4), p < 0.0001]. In addition, patients with self-limiting HCV evolution exhibited an expeditious, sharp decline of serial antibody values after SVC in comparison to those measured before SVC [median (interquartile range) s/co 56.0 (25.4-79.3) vs. 79.4 (66.3-103.0), p < 0.0001]. Conclusion: Our findings indicate a rapid short-term decline of antibody values in patients with acute spontaneous resolving HCV infection

Facial Indicators of Positive Emotions in Rats.

Until recently, research in animal welfare science has mainly focused on negative experi- ences like pain and suffering, often neglecting the importance of assessing and promoting positive experiences. In rodents, specific facial expressions have been found to occur in sit- uations thought to induce negatively valenced emotional states (e.g., pain, aggression and fear), but none have yet been identified for positive states. Thus, this study aimed to investi- gate if facial expressions indicative of positive emotional state are exhibited in rats. Adoles- cent male Lister Hooded rats (Rattus norvegicus, N = 15) were individually subjected to a Positive and a mildly aversive Contrast Treatment over two consecutive days in order to induce contrasting emotional states and to detect differences in facial expression. The Posi- tive Treatment consisted of playful manual tickling administered by the experimenter, while the Contrast Treatment consisted of exposure to a novel test room with intermittent bursts of white noise. The number of positive ultrasonic vocalisations was greater in the Positive Treatment compared to the Contrast Treatment, indicating the experience of differentially valenced states in the two treatments. The main findings were that Ear Colour became sig- nificantly pinker and Ear Angle was wider (ears more relaxed) in the Positive Treatment compared to the Contrast Treatment. All other quantitative and qualitative measures of facial expression, which included Eyeball height to width Ratio, Eyebrow height to width Ratio, Eyebrow Angle, visibility of the Nictitating Membrane, and the established Rat Gri- mace Scale, did not show differences between treatments. This study contributes to the exploration of positive emotional states, and thus good welfare, in rats as it identified the first facial indicators of positive emotions following a positive heterospecific play treatment. Fur- thermore, it provides improvements to the photography technique and image analysis for the detection of fine differences in facial expression, and also adds to the refinement of the tickling procedure. Introductio

Tickling procedure.

<p>The one-handed tickling procedure (a) consisted of one-handed repeated pinning, while rapidly stimulating the underside with the fingertips. The two-handed tickling procedure (b) consisted of scooping and supporting the animal with both hands, while vigorously tickling the sides and nape of the neck with the fingertips.</p

Qualitative and Quantitative measures taken for image analysis.

<p>Qualitative and Quantitative measures taken for image analysis.</p

Summary of inferential statistics for the quantitative measures.

<p>Summary of inferential statistics for the quantitative measures.</p

Examples of profile (a) and quarter (b) images.

<p>Profile images were selected for the assessment of quantitative measures as they allowed to detect more subtle differences across animals and treatments. Quarter images were used for qualitative measures as they showed more of the face and their assessment was only minimally affected by the head pointing upwards or downwards.</p