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1.  Climate Influences Fledgling Sex Ratio and Sex-Specific Dispersal in a Seabird 
PLoS ONE  2013;8(8):e71358.
Climate influences the dynamics of natural populations by direct effects over habitat quality but also modulating the phenotypic responses of organisms’ life-history traits. These responses may be different in males and females, particularly in dimorphic species, due to sex-specific requirements or constraints. Here, in a coastal seabird, the European shag (Phalacrocorax aristotelis), we studied the influence of climate (North Atlantic Oscillation, NAO; Sea Surface Temperature, SST) on two sex-related population parameters: fledgling sex ratio and sex-specific dispersal. We found that fledgling sex ratio was female skewed in NAO-positive years and male skewed in NAO-negative years. Accordingly, females dispersed a longer distance in NAO-positive years when females were overproduced, and on the contrary, males dispersed more in NAO-negative years. Overall, our findings provide rare evidence on vertebrates with genetic sex determination that climate conditions may govern population dynamics by affecting sex-specific density and dispersal.
doi:10.1371/journal.pone.0071358
PMCID: PMC3738640  PMID: 23951144
2.  Molecular epidemiology, antimicrobial susceptibilities and resistance mechanisms of Streptococcus pyogenes isolates resistant to erythromycin and tetracycline in Spain (1994–2006) 
BMC Microbiology  2012;12:215.
Background
Group A Streptococcus (GAS) causes human diseases ranging in severity from uncomplicated pharyngitis to life-threatening necrotizing fasciitis and shows high rates of macrolide resistance in several countries. Our goal is to identify antimicrobial resistance in Spanish GAS isolates collected between 1994 and 2006 and to determine the molecular epidemiology (emm/T typing and PFGE) and resistance mechanisms of those resistant to erythromycin and tetracycline.
Results
Two hundred ninety-five out of 898 isolates (32.8%) were erythromycin resistant, with the predominance of emm4T4, emm75T25, and emm28T28, accounting the 67.1% of the 21 emm/T types. Spread of emm4T4, emm75T25 and emm28T28 resistant clones caused high rates of macrolide resistance. The distribution of the phenotypes was M (76.9%), cMLSB (20.3%), iMLSB (2.7%) with the involvement of the erythromycin resistance genes mef(A) (89.5%), msr(D) (81.7%), erm(B) (37.3%) and erm(A) (35.9%).
Sixty-one isolates were tetracycline resistant, with the main representation of the emm77T28 among 20 emm/T types. To note, the combination of tet(M) and tet(O) tetracycline resistance genes were similar to tet(M) alone reaching values close to 40%. Resistance to both antibiotics was detected in 19 isolates of 7 emm/T types, being emm11T11 and the cMLSB phenotype the most frequent ones. erm(B) and tet(M) were present in almost all the strains, while erm(A), mef(A), msr(D) and tet(O) appeared in less than half of them.
Conclusions
Spanish GAS were highly resistant to macrolides meanwhile showed minor resistance rate to tetracycline. A remarkable correlation between antimicrobial resistance and emm/T type was noticed. Clonal spread of emm4T4, emm75T25 and emm28T28 was the main responsable for macrolide resistance where as that emm77T28 clones were it to tetraclycline resistance. A wide variety of macrolide resistance genes were responsible for three macrolide resistance phenotypes.
doi:10.1186/1471-2180-12-215
PMCID: PMC3490898  PMID: 22998619
GAS; emm gene; PFGE; Macrolide resistance; Tetracycline resistance
3.  Compensatory response ‘defends’ energy levels but not growth trajectories in brown trout, Salmo trutta L. 
Compensatory growth is an organism's reaction to buffer deviations from targeted trajectories. We explored the compensatory patterns of juvenile brown trout under field and laboratory conditions. Divergence of size and condition trajectories was induced by manipulating food levels in the laboratory and then releasing the trout into a river. In the stream, the length trajectories of food-restricted and control fish were parallel, but food-restricted fish exhibited partial compensation for mass and rapid recovery of condition. A laboratory experiment on similar sized fish did not provide evidence for compensatory growth in length or mass. In contrast, data matched the compensatory patterns shown in the stream: length trajectories were parallel and the convergence of mass trajectories ceased as soon as food-restricted fish recovered condition to the level of controls. These results show that (i) brown trout did not compensate for depression in structural growth and (ii) mass recovery was targeted to reinstate condition or energy reserves, but not size at a given age. This does not support the common view that compensatory growth can be a general response to growth depression. Rather, compensation in other salmonids could be related to size thresholds associated with developmental switches at the onset of sexual maturation and migration.
doi:10.1098/rspb.2004.2991
PMCID: PMC1564075  PMID: 15817434
compensatory growth; life-history; nutritional deficit; structural growth; Salmo trutta; storage

Results 1-3 (3)