Complete mitochondrial genome of Metapenaeus affinis (H. Milne Edwards, 1837) and Metapenaeus ensis (De Haan, 1844)

Penaeid shrimp is one of the marine germplasm resources in tropical and subtropical regions. To better understand shrimp germplasm resources and develop cultured shrimp species, the complete mitochondrial genome of Metapenaeus affinis and Metapenaeus ensis was assembled. The length of M. affinis and M. ensis mitochondrial sequences is 15,957 and 15,943, respectively. Both mitochondrial sequences contain 13 protein coding, 22 tRNA, and two rRNA genes. The GC content of the genome was 34.23% and 34.12% in M. affinis and M. ensis, respectively. Phylogenetic analysis indicated that the M. affinis and M. ensis are closely related, and assigned to a branch of Metapenaeus. We assembled and published the mitochondrial genome sequences of these two species, which will provide important information for the research and utilization of shrimp germplasm resources

Association analysis of alpha-amylase (AMY) and cathepsin L (CTSL) SNPs with growth traits in giant tiger shrimp Penaeus monodon

Alpha-amylase (AMY) and cathepsin-L (CTSL) were selected as candidate genes for SNP discovery for growth traits of P. monodon. Six SNPs were found in AMY and three in CTSL in P. monodon. Association analyses for the candidate SNPs with important economic traits were performed in populations. That allele A at CTLS-213 SNP, AA, and GA, tended to be associated with increased body weight. Shrimps with genotype GG had significantly smaller CL, CW, and CH values than those with GT and TT genotypes (P < 0.05). While CTLS-820 SNP was found to be significantly associated with CH and FSL (P <0.05). These SNPs will be valid for marker-assisted selection breeding programs in P. monodon

Effects of replacing dietary fishmeal with zymolytic black soldier fly larvae on the growth performance of the mud crab (<em>scylla paramamosain</em>) larvae

Black soldier fly have been shown to be one of the optimal alternatives to fishmeal, but there are few reports on the effects of zymolytic black soldier fly larvae (ZBSFL) on the growth and digestion of crustaceans. An 8-week feeding trial was conducted to evaluate the effects of different replacement levels of ZBFLS on growth performance, body composition, and digestive enzyme activity of the mud crab larvae. Four diets were formulated by replacing fishmeal with 0%, 5%, 10% and 15% ZBSFL in the basal diet. Crab larvae were randomly divided into four groups of three replicates each and fed twice daily. The results showed that the SR of crab larvae was higher than that of the no-substitution group when the substitution rate reached 5% (P < 0.05). There was no significant change in SR when the substitution rate was further increased. Weight growth rate and Specific growth rate were similar, both highest at 10% substitution ratio. The crude protein content of whole crab larvae gradually increased as the proportion of FM substituted by ZBSFL increased. The lipid content of whole crab larvae in the 5% substitution ratio group was significantly higher than that in all other groups (P < 0.05). Meanwhile. The activities of amylase, protease and lipase gradually increased. In this experiment, when the percentage of ZBSFL substitution for FM reached 10%, its growth performance was optimal, with higher SR, less negative effects and more balanced indicators in all aspects. When the substitution rate was further increased, it might increase the digestive burden of the crab and negatively affect its growth

Development and Validation of Prediction Scores for Early Mortality at Transition to Dialysis.

ObjectiveTo develop and validate a risk prediction model that would help individualize treatment and improve the shared decision-making process between clinicians and patients.Patients and methodsWe developed a risk prediction tool for mortality during the first year of dialysis based on pre-end-stage renal disease characteristics in a cohort of 35,878 US veterans with incident end-stage renal disease who transitioned to dialysis treatment between October 1, 2007, and March 31, 2014 and then externally validated this tool among 4284 patients in the Kaiser Permanente Southern California (KPSC) health care system who transitioned to dialysis treatment between January 1, 2007, and September 30,&nbsp;2015.ResultsTo ensure model goodness of fit, 2 separate models were selected for patients whose last estimated glomerular filtration rate (eGFR) before dialysis initiation was less than 15 mL/min per 1.73 m2 or 15 mL/min per 1.73 m2 or higher. Model discrimination in the internal validation cohort of veterans resulted in C statistics of 0.71 (95% CI, 0.70-0.72) and 0.66 (95% CI, 0.65-0.67) among patients with eGFR lower than 15 mL/min per 1.73 m2 and 15 mL/min per 1.73 m2 or higher, respectively. In the KPSC external validation cohort, the developed risk score exhibited C statistics of 0.77 (95% CI, 0.74-0.79) in men and 0.74 (95% CI, 0.71-0.76) in women with eGFR lower than 15 mL/min per 1.73 m2 and 0.71 (95% CI, 0.67-0.74) in men and 0.67 (95% CI, 0.62-0.72) in women with eGFR of 15 mL/min per 1.73 m2 or higher.ConclusionA new risk prediction tool for mortality during the first year after transition to dialysis (available at www.DialysisScore.com) was developed in the large national Veterans Affairs cohort and validated with good performance in the racially, ethnically, and gender diverse KPSC cohort. This risk prediction tool will help identify high-risk populations and guide management strategies at the transition to dialysis

Variation of bacterial communities in black tiger shrimp (Penaeus monodon) with different growth performances

The intestinal bacteria of aquatic animals are closely related to their health and growth status. Penaeus monodon has become an important aquaculture species in the world because of its high nutritional value and market to demand. However, knowledge of bacterial communities on the growth phenotype of P. monodon is still limited. In this research, the bacterial community were comprehensively analyzed by using Miseq sequencing technology and bioinformatics. The results indicated that 29 phyla and 468 genera were identified by the taxonomic sequence. The data showed that the composition of microbial community was statistically different to fast-growing shrimps and slow-growing shrimps. There were significant differences in intestinal bacteria at the genus level. Lactococcus, Limnothrix, and Arthrospira had more abundance in the gut of fast-growing shrimps, which may promote the growth of P. monodon by affecting enzyme activities and improving immune response. Nautella, Shimia, Pseudoalteromonas, Aliiroseovarius, Albimonas, Tessaracoccus had more abundance in the gut of slow-growing shrimps. Nautella had the ability to express virulence by stimulated by environmental factors, thereby increasing the susceptibility to infection, which may have a negative impact on healthy growth of shrimps. Pseudoalteromonas, Aliiroseovarius and Shimia were related to the pathogenicity of shrimp, which may be an important factor affecting the growth of shrimp. Overall, this study demonstrates that the bacterial community associated with P. monodon was variation on different growth performance. These results can provide information on microbiome characteristics involved in the asynchronous growth of shrimp

SHEEP GRAZING STIMULATED PLANT AVAILABLE SOIL NITRATE ACCUMULATION IN A TEMPERATE GRASSLAND

We investigated the effects of increasing grazing I ntensities on N availability (inorganic N, In-N, for plant and microbial growth, e.g., NO3--N, NH4+-N) and variability in soils of 0-10 cm depth during 2009-2010, within a framework of a long-term grazing study. The results showed that the relationship for grazing intensity with respect to soil NO3--N (R-2 = 0.988, P = 0.006) was well depicted by curvilinear equations. Moreover, soil NO3--N, NH4+-N and inorganic N varied significantly with sample date, year, and soil water content (SWC, %). There were also significant correlation between date and grazing intensities on soil NO3--N, NH4+-N and In-N. SWC and temperature had more impact on soil available N than grazing, especially with respect to the seasonal dynamics of the soil N pool. Grazing intensity, in combination with SWC (precipitation) and temperature, controlled soil N availability and, therefore, affect the N cycles and plant growth within semiarid grasslands

SHEEP GRAZING STIMULATED PLANT AVAILABLE SOIL NITRATE ACCUMULATION IN A TEMPERATE GRASSLAND

We investigated the effects of increasing grazing I ntensities on N availability (inorganic N, In-N, for plant and microbial growth, e.g., NO3--N, NH4+-N) and variability in soils of 0-10 cm depth during 2009-2010, within a framework of a long-term grazing study. The results showed that the relationship for grazing intensity with respect to soil NO3--N (R-2 = 0.988, P = 0.006) was well depicted by curvilinear equations. Moreover, soil NO3--N, NH4+-N and inorganic N varied significantly with sample date, year, and soil water content (SWC, %). There were also significant correlation between date and grazing intensities on soil NO3--N, NH4+-N and In-N. SWC and temperature had more impact on soil available N than grazing, especially with respect to the seasonal dynamics of the soil N pool. Grazing intensity, in combination with SWC (precipitation) and temperature, controlled soil N availability and, therefore, affect the N cycles and plant growth within semiarid grasslands