Does access to the bluestreak cleaner wrasse Labroides dimidiatus affect indicators of stress and health in resident reef fishes in the Red Sea?

Interactions between the bluestreak cleaner wrasse Labroides dimidiatus and its client reef fish are a textbook example of interspecific mutualism. The fact that clients actively visit cleaners and invite inspection, together with evidence that cleaners eat many client ectoparasites per day, indeed strongly suggests a mutualistic relationship. What remains unknown is how parasite removal affects the physiology of clients and thereby their body condition, health, and immune function. Here we addressed these issues in a field study in Ras Mohammed National Park, Egypt. In our study area, small reef patches are inter-spaced with areas of sandy substrate, thereby preventing many species (i.e., residents, including cleaner wrasses) from travelling between the reef patches. This habitat structure leads to a mosaic of resident clients with and without access to bluestreak cleaner wrasses, further referred to as "cleaner access", on which we focused our study. We found that residents with cleaner access had higher body condition than residents without cleaner access. However, indicators of stress like variation in cortisol levels corrected for handling time and various immune parameters were apparently unaffected by cleaner access. In fact antibody responses were significantly higher in fishes without cleaner access. This suggests that cleaner access decreases the need for active immunity and that this releases resources that might be allocated to other functions such as somatic growth and reproduction.

Unhelpful beliefs and attitudes about low back pain in the general population: A cross-sectional survey.

BACKGROUND: Unhelpful beliefs about non-specific low back pain (LBP) are associated with poorer coping strategies and unhelpful behaviours. Furthermore, targeting unhelpful beliefs about back pain has been advanced as a major priority to decrease the burden of LBP. Therefore, studies exploring these beliefs are needed to adapt the message delivered to the population. OBJECTIVES: To identify attitudes and beliefs about LBP in the general population in French-speaking Switzerland and to analyse their association with individual characteristics and the belief that exercise is an effective treatment for LBP. DESIGN: Cross-sectional study. METHOD: Attitudes and beliefs were measured with the Back-Pain Attitudes Questionnaire (Back-PAQ). Individual characteristics and participants' beliefs about the effectiveness of exercise for LBP were collected to determine their association with Back-PAQ score. RESULTS: The questionnaire was completed by 1129 participants. Unhelpful beliefs were widespread (mean (SD) Back-PAQ score: 113.2 (10.6)), especially those that the back needs protection, is easy to injure and that the nature of LBP is special. Only 55% of the participants believed exercise to be one of the most effective treatment for LBP. Individual characteristics only explained 4% of the Back-PAQ score variance. CONCLUSION: French-speaking Swiss general population has high levels of unhelpful beliefs and moderate confidence in the effectiveness of exercise for LBP, though the message "staying active is good for LBP" was well understood. The messages to decrease the level of unhelpful beliefs about LBP in the population should specifically target the vulnerability, protection and special nature of LBP, and promote exercise therapy.