An opinion paper: emphasis on white muscle development and growth to improve farmed fish flesh quality

Due to rapid depletion of wild stocks, the necessity to cultivate fish is eminent. Current fish farming practices seek to improve flesh quality. The notion that white muscles are the main target of the fishing industry is emphasized. A novel approach is suggested based on the development of white muscles in wild fish from eggs to adults. A compilation of facts about white muscle structure, function and ontogeny is followed by an account of the changes in swimming behaviour and performance related to the use of white muscle during growth from larva to adult. Ecological data narrate early swimming performance with white muscle development and growth, unveiling some of the important natural selection factors eliminating weak swimmers and poor growers from the breeding stock. A comparison between fish culture practise and natural conditions reveals fundamental differences. New approaches following wild breeding processes promise several important advantages regarding the quality of white muscle

Mortality prediction models for pediatric intensive care:comparison of overall and subgroup specific performance

<p>To validate paediatric index of mortality (PIM) and pediatric risk of mortality (PRISM) models within the overall population as well as in specific subgroups in pediatric intensive care units (PICUs).</p><p>Variants of PIM and PRISM prediction models were compared with respect to calibration (agreement between predicted risks and observed mortality) and discrimination (area under the receiver operating characteristic curve, AUC). We considered performance in the overall study population and in subgroups, defined by diagnoses, age and urgency at admission, and length of stay (LoS) at the PICU. We analyzed data from consecutive patients younger than 16 years admitted to the eight PICUs in the Netherlands between February 2006 and October 2009. Patients referred to another ICU or deceased within 2 h after admission were excluded.</p><p>A total of 12,040 admissions were included, with 412 deaths. Variants of PIM2 were best calibrated. All models discriminated well, also in patients <28 days of age (neonates), with overall higher AUC for PRISM variants (PIM = 0.83, PIM2 = 0.85, PIM2-ANZ06 = 0.86, PIM2-ANZ08 = 0.85, PRISM = 0.88, PRISM3-24 = 0.90). Best discrimination for PRISM3-24 was confirmed in 13 out of 14 subgroup categories. After recalibration PRISM3-24 predicted accurately in most (12 out of 14) categories. Discrimination was poorer for all models (AUC <0.73) after LoS of > 6 days at the PICU.</p><p>All models discriminated well, also in most subgroups including neonates, but had difficulties predicting mortality for patients > 6 days at the PICU. In a western European setting both the PIM2(-ANZ06) or a recalibrated version of PRISM3-24 are suited for overall individualized risk prediction.</p>