In search of the optimum stocking density for chum salmon (Oncorhynchus keta) eggs in shallow matrix substrate incubators

Within the tested range of 1000 - 7000 eyed eggs/ft² gravel substrate (1.08 - 7.53 eggs/cm²), the optimum stocking density for chum salmon (Oncorhynchus keta) eggs in shallow matrix substrate incubators occurred at 3000 - 4000 eggs/ft². Premature fry, which predominated early emergence, showed greater variability in lipid content than fry at peak emergence. Cumulative premature fry emergence was lowest at 3000 - 4000 eggs/ft² and highest at 5000 - 7000 eggs/ft². Early emerging fry are considered to be of lesser quality than peak emerging fry because the observed increase in variation in lipid content (i.e. primary energy reserve) may lead to increased variation in survival during seaward migration. Neither survival (from egg stocking to emergence) nor the gross body composition (determined by proximate analysis) of emerging fry were affected by egg stocking density. Development indices decreased in a linear fashion throughout emergence but the slope and intercept of the line did not differ among egg stocking densities. The frequency of yolk sac abnormalities was negligible in all treatments. The water content of fry increased from early to late emergence while dry weights remained relatively constant. The implications of this observation are discussed

A genetic fitness model for fisheries management

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Using Participatory Scenarios to Stimulate Social Learning for Collaborative Sustainable Development

Interdependent human and biophysical systems are highly complex and behave in unpredictable and uncontrollable ways. Social and ecological challenges that emerge from this complexity often defy straightforward solutions, and efforts to address these problems will require not only scientific and technological capabilities but also learning and adaptation. Scenarios are a useful tool for grappling with the uncertainty and complexity of social-ecological challenges because they enable participants to build adaptive capacity through the contemplation of multiple future possibilities. Furthermore, scenarios provide a platform for social learning, which is critical to acting in the face of uncertain, complex, and conflict-laden problems. We studied the Minnesota 2050 project, a collaborative project through which citizens collectively imagined future scenarios and contemplated the implications of these possibilities for the adaptability of their social and environmental communities. Survey and interview data indicate that these participatory scenario workshops built and strengthened relationships, enhanced participants’ understanding of other perspectives, and triggered systemic thinking, all of which is relevant to collective efforts to respond to social-ecological challenges through sustainable development activities. Our analysis shows that participatory scenarios can stimulate social learning by enabling participants to engage and to discuss options for coping with uncertainty through collaborative actions. Such learning can be of value to participants and to the organizations and decisions in which they are engaged, and scenario processes can be effective tools for supporting collaborative sustainable development efforts

Towards Sustainable Aquafeeds: Evaluating Substitution of Fishmeal with Lipid-extracted Microalgal Co-product (Nannochloropsis Oculata) in Diets of Juvenile Nile Tilapia (Oreochromis Niloticus)

Microalgae companies increasingly seek markets for defatted biomass that is left over after extracting omega-3 rich oil for human nutraceuticals and crude oil for fuels. Such a protein-rich co-product is a promising alternative to unsustainably sourced fishmeal in aquaculture diets. We report the first evaluation of co-product of the marine microalga Nannochloropsis oculata(N. oculata co-product) for replacing fishmeal in diets of Nile tilapia, a globally important aquaculture species. We conducted a nutrient digestibility experiment with N. oculata dried whole cells and N. oculata co-product, followed by an 84-day nutritional feeding experiment with N. oculata co-product. N. oculata co-product, more nutrient-dense than whole cells, had the highest digestibility for lysine, an essential amino acid that is often deficient in terrestrial crop meals; and for 20:5 n-3 EPA, making it a good option for EPA supplementation in tilapia feed. N. oculata co-product, despite containing higher amounts of protein than whole cells, had significantly lower digestibility for crude protein than whole cells. Apparent digestibility coefficients (ADC) of methionine were significantly lower in N. oculata co-product than in whole cells. The nutritional feeding experiment compared diets with N. oculata co-product that replaced fishmeal as follows: 0% replacement in reference diet (fishmeal as 7% of total diet) and test diets with 33%, 66% and 100% replacement of fishmeal (3%, 5.5%, and 8% of total diet, respectively). Results showed the 33% replacement diet yielded fish growth, feed conversion, and survival similar to the reference diet. Reduced digestibility and growth at greater N. oculata co-product inclusion levels may have been due to higher levels of anti-nutrients in co-product than whole cells. All diets yielded a n3:n6 ratio of tilapia fillet that is favorable for human consumption. Depositions of macro minerals and several trace elements in the fillet were not significantly different across diets. Thus, N. oculata co-product, when replacing 33% of fishmeal in tilapia feed, led to fish performance and flesh composition comparable to that of fish fed the reference diet, but its nutrient digestibility needs to be improved to achieve higher replacement levels

Breast cancer risk variants at 6q25 display different phenotype associations and regulate ESR1, RMND1 and CCDC170.

We analyzed 3,872 common genetic variants across the ESR1 locus (encoding estrogen receptor α) in 118,816 subjects from three international consortia. We found evidence for at least five independent causal variants, each associated with different phenotype sets, including estrogen receptor (ER(+) or ER(-)) and human ERBB2 (HER2(+) or HER2(-)) tumor subtypes, mammographic density and tumor grade. The best candidate causal variants for ER(-) tumors lie in four separate enhancer elements, and their risk alleles reduce expression of ESR1, RMND1 and CCDC170, whereas the risk alleles of the strongest candidates for the remaining independent causal variant disrupt a silencer element and putatively increase ESR1 and RMND1 expression.This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/ng.352

Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10-20), ER-negative BC (P=1.1 × 10-13), BRCA1-associated BC (P=7.7 × 10-16) and triple negative BC (P-diff=2 × 10-5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10-3) and ABHD8 (P<2 × 10-3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk

Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation.

GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Project data. All but two, strongly correlated SNPs (rs4442975 G/T and rs6721996 G/A) are excluded as candidate causal variants at odds against >100:1. The best functional candidate, rs4442975, is associated with oestrogen receptor positive (ER+) disease with an odds ratio (OR) in Europeans of 0.85 (95% confidence interval=0.84-0.87; P=1.7 × 10(-43)) per t-allele. This SNP flanks a transcriptional enhancer that physically interacts with the promoter of IGFBP5 (encoding insulin-like growth factor-binding protein 5) and displays allele-specific gene expression, FOXA1 binding and chromatin looping. Evidence suggests that the g-allele confers increased breast cancer susceptibility through relative downregulation of IGFBP5, a gene with known roles in breast cell biology

Comparison of 6q25 Breast Cancer Hits from Asian and European Genome Wide Association Studies in the Breast Cancer Association Consortium (BCAC)

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