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Significant relations were observed between select infant-care and weaning behaviors and growth in body weight in common marmoset monkeys (Callithrix jacchus). The patterns of these relations suggest that earlier occurrence of developmental milestones, such as cessation of transport (being off carriers) and weaning to solid food, were associated with slower growth during the subsequent period. In contrast, more frequent nursing bouts during the period in which weaning was initiated were associated with higher growth rates. In the case of being off carriers, these effects did not carry over to older ages, suggesting that any deficits in growth were temporary. In the case of earlier, more frequent consumption of solid food, there was some suggestion that there were longer-term effects, followed by catch-up growth. The knee-to-heel length of subjects was not related to the measured behaviors. There was no relation between early weaning to solid food and leanness at day 75, suggesting that, although this behavior was affecting overall weight, it did not affect relative gains of fat versus lean mass. There were, however, significant correlations between cessation of transport or frequency of nursing bouts during the weaning period and leanness, with earlier cessation of transport and less frequent nursing associated with leaner infants, after weaning. Our results differed from those of a previous study that found a relation between linear growth and abuse in this species, with abuse defined as physical injury by other members of the group. We found no differences in growth between abused and nonabused infants. However, abused infants had lower birth weight.

From 2011 to 2013, anadromous brown trout Salmo trutta (213-730 mm, total body length, LT) were collected during or shortly after their marine feeding migration at 7 different localities in central Norway. The mean volume of stomach content (%) of marine fish prey eaten by S. trutta captured in marine waters varied from 34 to 89%. There was a high prevalence (67-100%) for parasite groups potentially transmitted by marine prey fish (i.e. nematodes, cestodes and trematodes) at all sampling sites. There was a significant overlap in the signatures of both δ13C and δ15N in the muscle tissue between the 7 groups of S. trutta; however, individual variation within groups was large. A strong positive relationship between δ13C and LT indicated size-dependent niche selection, with smaller individuals feeding less on marine prey and more on brackish or freshwater invertebrates in the estuary. Short-term gut contents data and trophically transmitted parasites showed that all size groups were feeding on marine fish. However, an increased dependence upon marine prey fish by larger S. trutta was indicated by a strong positive relationship between LT and δ15N. Similarities in S. trutta feeding and time-integrated trophic tracers (stable isotopes and parasites) across the 7 localities supports the general view that S. trutta feed within similar marine trophic niches. This similarity in feeding niche requirements may make S. trutta populations vulnerable to anthropogenic ecosystem perturbations which reduce the diversity of potential marine prey items.

Significant relations were observed between select infant-care and weaning behaviors and growth in body weight in common marmoset monkeys (Callithrix jacchus). The patterns of these relations suggest that earlier occurrence of developmental milestones, such as cessation of transport (being off carriers) and weaning to solid food, were associated with slower growth during the subsequent period. In contrast, more frequent nursing bouts during the period in which weaning was initiated were associated with higher growth rates. In the case of being off carriers, these effects did not carry over to older ages, suggesting that any deficits in growth were temporary. In the case of earlier, more frequent consumption of solid food, there was some suggestion that there were longer-term effects, followed by catch-up growth. The knee-to-heel length of subjects was not related to the measured behaviors. There was no relation between early weaning to solid food and leanness at day 75, suggesting that, although this behavior was affecting overall weight, it did not affect relative gains of fat versus lean mass. There were, however, significant correlations between cessation of transport or frequency of nursing bouts during the weaning period and leanness, with earlier cessation of transport and less frequent nursing associated with leaner infants, after weaning. Our results differed from those of a previous study that found a relation between linear growth and abuse in this species, with abuse defined as physical injury by other members of the group. We found no differences in growth between abused and nonabused infants. However, abused infants had lower birth weight.

Animal movement occurs as a function of many factors including changing environmental conditions (e.g., seasonality) and the internal state (e.g., phenotypic traits) of the focal organism. Identifying how these factors interact can reveal behavioral patterns that would otherwise go undiscovered. Given a large sample size of individuals (n = 187), we used acoustic biotelemetry to examine the spatial ecology of adfluvial bull trout (Salvelinus confluentus (Suckley, 1859)) in a large hydropower reservoir in British Columbia, Canada. Dependent variables, including home-range size and lateral movement, were analysed as a function of interactive relationships among seasons (over a 2-year period) and phenotypic traits. Mixed models indicated relationships between home-range size and season, whereas variation in lateral movement was explained by month and a two-way interaction between sex and body size. Large females (765 mm total length) were estimated to move laterally up to five times greater than females half their length, whereas movements between large and small males were not significantly different. This study shows how body size and sex can have a profound and possible interactive effect on animal movement. In addition, the results offer new information on the spatial ecology and conservation of adfluvial bull trout. Key words: spatial ecology, home range, phenotypic traits, biotelemetry, char. Les deplacements des animaux sont fonction de nombreux facteurs dont des conditions ambiantes changeantes (p. ex. la saisonnalite) et l'etat interne (p. ex. des caracteres phenotypiques) de l'organisme concerne. La determination des interactions entre ces facteurs peut reveler des motifs comportementaux qui, autrement, resteraient non deceles. Etant donne un grand echantillon d'individus (n = 187), nous avons utilise la biotelemetrie acoustique pour examiner l'ecologie spatiale de truites a tete plate (Salvelinus confluentus (Suckley, 1859)) adfluviales dans un grand reservoir hydroelectrique en Colombie- Britannique (Canada). Des variables dependantes, dont la taille du domaine vital et les deplacements lateraux, ont ete analysees en fonction de relations interactives d'une saison a l'autre (sur une periode de 2 annees) et de caracteres phenotypiques. Des modeles mixtes indiquaient des relations entre la taille du domaine vital et la saison, alors que les variations des deplacements lateraux s'expliquaient selon le mois et une interaction bilaterale entre le sexe et la taille du corps. Il a ete estime que les grandes femelles (longueur totale de 765 mm) se deplacaient lateralement jusqu'a cinq fois plus que les femelles deux fois moins longues, alors qu'il n'y avait pas de difference significative entre les deplacements des grands et petits males. L'etude illustre comment la taille du corps et le sexe peuvent exercer un important effet interactif possible sur les deplacements des animaux. Les resultats fournissent en outre de nouveaux renseignements sur l'ecologie spatiale et la conservation des truites a tete plate adfluviales. [Traduit par la Redaction] Mots-cles: ecologie spatiale, domaine vital, caracteres phenotypiques, biotelemetrie, omble., Introduction Animal movement is a necessary component of wildlife management and is increasingly investigated in the ecological and behavioral sciences (Caro 2007; Holyoak et al. 2008). Identifying behavioral modifications in [...]

Objective: To deal with the question of whether a 5-point response Likert scale should be changed to a 3-point scale when used in the field testing of people with intellectual disabilities (IDs), which was raised after the pilot study of World Health Organization Quality of Life (WHOQOL)-DIS, a module being developed with the World Health Organization measure of quality of life for disabilities. Methods: Three possible ways were used to generate hypothetical data by merging a 5-point scale into a 3-point scale. The analyses were based on both item response theory and classical measurement theory. The partial credit model for polytomous response was performed for item evaluation; the confirmatory factor analysis was used to check construct validity, the Cronbach's alpha for domain reliability, and correlation analyses for the relationship between the 5-point scale and the generated 3-point scale. Results: Most items with a 5-point response scale had disordered response options and/or unequal-length intervals between successive response options; these deficiencies were removed or improved without decline of validity and reliability in the hypothetical data of 3-point scales. Conclusion: Instead of the 5-point scale, a 3-point scale could be used for IDs in the field test of developing the module WHOQOL-DIS.

Background: This paper describes the development of an Attitudes to Disability Scale for use with adults with physical or intellectual disabilities (ID). The aim of the research was to design a scale that could be used to assess the personal attitudes of individuals with either physical or ID. Method: The measure was derived following standard WHOQOL methodology as part of an international trial. In the pilot phase of the study, 12 centres from around the world carried out focus groups with people with physical disabilities, people with ID, with their carers, and with relevant professionals in order to identify themes relevant for attitudes to disability. Items generated from the focus groups were then tested in a pilot study with 1400 respondents from 15 different centres worldwide, with items being tested and reduced using both classical and modern psychometric methods. A field trial study was then carried out with 3772 respondents, again with the use of both classical and modern psychometric methods. Results: The outcome of the second round of data collection and analysis is a 16-item scale that can be used for assessment of attitudes to disability in physically or intellectually disabled people and in healthy respondents. Conclusions: The Attitudes to Disability Scale is a new psychometrically sound scale that can be used to assess attitudes in both physically and intellectually disabled groups. The scale is also available in both personal and general forms and in a number of different language versions.