•Long-term positive effects of cognitive enrichment on fish welfare.•Feeding predictability enhanced fish immune responses and reduced stress status.•Less aggressive and abnormal behaviours before ...feedings.•Nuanced swimming activity: increased before feedings and decreased between feedings.•Cognitive enrichment is a promising and practical way to improve farmed fish welfare.
Cognitive enrichment is a promising but understudied type of environmental enrichment that aims to stimulate the cognitive abilities of animals by providing them with more opportunities to interact with (namely, to predict events than can occur) and to control their environment. In a previous study, we highlighted that farmed rainbow trout can predict daily feedings after two weeks of conditioning, the highest conditioned response being elicited by the combination of both temporal and signalled predictability. In the present study, we tested the feeding predictability that elicited the highest conditioned response in rainbow trout (both temporal and signalled by bubbles, BUBBLE + TIME treatment) as a cognitive enrichment strategy to improve their welfare. We thus analysed the long-term effects of this feeding predictability condition as compared with an unpredictable feeding condition (RANDOM treatment) on the welfare of rainbow trout, including the markers in the modulation of brain function, through a multidisciplinary approach. To reveal the brain regulatory pathways and networks involved in the long-term effects of feeding predictability, we measured gene markers of cerebral activity and plasticity, neurotransmitter pathways and physiological status of fish (oxidative stress, inflammatory status, cell type and stress status). After almost three months under these predictability conditions of feeding, we found clear evidence of improved welfare in fish from BUBBLE + TIME treatment. Feeding predictability allowed for a food anticipatory activity and resulted in fewer aggressive behaviours, burst of accelerations, and jumps before mealtime. BUBBLE + TIME fish were also less active between meals, which is in line with the observed decreased expression of transcripts related to the dopaminergic system. BUBBLE + TIME fish tented to present fewer eroded dorsal fin and infections to the pathogen Flavobacterium psychrophilum. Decreased expression of most of the studied mRNA involved in oxidative stress and immune responses confirm these tendencies else suggesting a strong role of feeding predictability on fish health status and that RANDOM fish may have undergone chronic stress. Fish emotional reactivity while isolated in a novel-tank as measured by fear behaviour and plasma cortisol levels were similar between the two treatments, as well as fish weight and size. To conclude, signalled combined with temporal predictability of feeding appears to be a promising approach of cognitive enrichment to protect brain function via the physiological status of farmed rainbow trout in the long term.
Aims
This study aimed to evaluate in vitro efficacy of essential oils (EOs) and their compounds (EOCs) alone or in combination against Aeromonas salmonicida subsp. salmonicida, the causative agent of ...furunculosis in salmonid fish.
Methods and Results
Antimicrobial activity of 13 EOs and 16 EOCs was investigated for four A. salmonicida subsp. salmonicida strains using broth microdilution. The checkerboard assay was used to evaluate a putative synergy between the most efficient EOs and EOCs against the tested strains. Cinnamon bark, oregano, clove, and thyme oils and their major compounds cinnamaldehyde, eugenol, carvacrol and thymol showed the lower minimum inhibitory concentration and minimum bactericidal concentration values. The association of cinnamaldehyde and eugenol (V/V: 30%/70%) showed a synergistic activity against three tested strains. The combinations of cinnamon with oregano, clove or thyme EOs showed a neutral or additive activity against all the tested strains.
Conclusions
Cinnamon, oregano, clove and thyme oils and their major phytochemical compounds showed strong activities against A. salmonicida subsp. salmonicida strains.
Significance and Impact of the Study
To reduce the use of antibiotics in aquaculture, phytochemicals such as cinnamaldehyde and eugenol can be tested alone or in combination in in vivo studies as functional feed alternatives.
Chronic self‐promoters may thrive in job interviews where such behavior is encouraged. In Study 1, 72 participants were videotaped as they simulated the job applicant role. Accountability was ...manipulated by the expectation of expert versus nonexpert interviewers. As accountability increased, self‐promotion tended to decrease among non‐narcissists but increase among narcissists. Ingratiation showed no interaction or main effects. In Study 2, 222 raters evaluated applicant videos varying in narcissism (high vs. low) and ethnicity (European heritage vs. East Asian heritage). Chronic self‐promoters (i.e., European‐heritage narcissists) were given the most positive evaluations. Detailed behavior analyses indicated that the narcissism advantage was derived primarily from frequent self‐praise and the European‐heritage advantage from use of active ingratiation tactics. In sum, self‐presentation styles that pay off in the (Western) interview context are highly selective.
Focal areas of high signal intensity are T2WI/T2-FLAIR hyperintensities frequently found on MR imaging of children diagnosed with neurofibromatosis type 1, often thought to regress spontaneously ...during adolescence or puberty. Due to the risk of tumor in this population, some focal areas of high signal intensity may pose diagnostic problems. The objective of this study was to assess the characteristics and temporal evolution of focal areas of high signal intensity in children with neurofibromatosis type 1 using long-term follow-up with MR imaging.
We retrospectively examined the MRIs of children diagnosed with neurofibromatosis type 1 using the National Institutes of Health Consensus Criteria (1987), with imaging follow-up of at least 4 years. We recorded the number, size, and surface area of focal areas of high signal intensity according to their anatomic distribution on T2WI/T2-FLAIR sequences. A generalized mixed model was used to analyze the evolution of focal areas of high signal intensity according to age, and separate analyses were performed for girls and boys.
Thirty-nine patients (ie, 285 MR images) with a median follow-up of 7 years were analyzed. Focal areas of high signal intensity were found in 100% of patients, preferentially in the infratentorial white matter (35% cerebellum, 30% brain stem) and in the capsular lenticular region (22%). They measured 15 mm in 95% of cases. They appeared from the age of 1 year; increased in number, size, and surface area to a peak at the age of 7; and then spontaneously regressed by 17 years of age, similarly in girls and boys.
Focal areas of high signal intensity are mostly small (<15 mm) abnormalities in the posterior fossa or capsular lenticular region. Our results suggest that the evolution of focal areas of high signal intensity is not related to puberty with a peak at the age of 7 years. Knowledge of the predictive evolution of focal areas of high signal intensity is essential in the follow-up of children with neurofibromatosis type 1.
We investigate the impact of the growth conditions of AlGaAsSb cladding layers on the properties of interband cascade lasers (ICLs). For an optimized structure emitting at 3.3 µm, we achieve an ...internal quantum efficiency of 65% per stage in good agreement with conventional ICL using InAs/AlSb superlattice cladding layers, in spite of internal losses of 15 cm −1 due to higher optical losses in the n-type AlGaAsSb alloys. Finally, we report a narrow ridge ICL emitting at 3.33 µm operating in continuous wave up to 80°C that produces 1 mW/uncoated facet at 80°C, 10 mW at 40°C and more than 12 mW at 20°C.
Flavobacterium psychrophilum is the causative agent of “bacterial cold water disease” and “rainbow trout fry syndrome” in salmonid farming worldwide. These diseases, especially rainbow trout fry ...syndrome, are among the main hazards for French aquaculture. In this study, a multilocus sequence typing approach (MLST) was used to evaluate the genetic diversity of this bacterium.
Seven housekeeping genes in a set of 66 isolates were investigated. They were recently collected from rainbow trout during clinical episodes in French farms from the two main geographical areas of production. A total of 5808bp of sequence were analyzed for each isolate and showed relatively low levels of gene (H=0.4313) and nucleotide (π×100=0.31%) diversities. MLST identified 15 sequence types (STs), of which 14 have never been described. eBURST analysis separated the 15 STs in one clonal complex of 8 genetically related STs (with ST2 as founder) and 7 singletons. Genetic diversity was largely due to recombination, as demonstrated by a pairwise homoplasy index (PHI=5.35×10−9) significantly different from zero (p<0.05). The evolution of standardized association index (IAS) (all isolates: 0.6088, p<0.05; single representative of STs: 0.4567, p<0.05; and clusters of STs: 0.084, p>0.05), showed an epidemic structure of the population.
These results emphasized the expansion of a limited number of dominant genetic variants in French clinical F. psychrophilum isolates from a single host species, with no geographic relationships.
Efficient mode-locking in a Tm:KY(WO(4))(2) laser is demonstrated by using InGaAsSb quantum-well SESAMs. Self-starting ultrashort pulse generation was realized in the 1979-2074 nm spectral region. ...Maximum average output power up to 411 mW was produced around 1986 nm with the corresponding pulse duration and repetition rate of 549 fs and 105 MHz respectively. Optimised pulse durations of 386 fs were produced with an average power of 235 mW at 2029 nm.
We report, for the first time to our knowledge, femtosecond-pulse operation of a Tm,Ho:NaY(WO(4))(2) laser at around 2060 nm. Transform-limited 191 fs pulses are produced with an average output power ...of 82 mW at a 144 MHz pulse repetition frequency. Maximum output power of up to 155 mW is generated with a corresponding pulse duration of 258 fs. An ion-implanted InGaAsSb quantum-well-based semiconductor saturable absorber mirror is used for passive mode-locking maintenance.
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