Condition Indices as Surrogates of Energy Density and Lipid Content in Juveniles of Three Fish Species

To guide the selection of condition indices for juvenile fishes, we compared the ability of several indirect condition indices (those based on length-mass relationships, the hepatosomatic index, and relative lipid estimates from the Distell fish fatmeter) to assess energy density and lipid content of Summer Flounder Paralichthys dentatus, Striped BassMorone saxatilis, and Atlantic Croakers Micropogonias undulatus. These species use estuarine areas as nurseries, but they have different life history strategies and ecological niches that affect their energy storage strategies. We tested hypotheses that differences in the distribution and role of lipids as energy stores among species would influence the suitability of condition indices for estimating energy and lipid content. Length-based indices were most suitable for estimating energy and lipid content of juvenile Summer Flounder and Striped Bass, suggesting that length-based indices may be appropriate for juveniles that store energy as proteins (i.e., juveniles with low lipid content). The fatmeter suitably predicted energy and lipid content of Atlantic Croakers, indicating its potential for assessing condition of juveniles that store lipids for migration and that display a high range of observed lipid content. Even though a small size range was examined, fish length improved predictions of energy and lipid content for some of the indirect condition indices for Atlantic Croakers and Summer Flounder, suggesting that fish length should be considered when developing relationships among measures of condition. The selection of condition indices should be tailored to the life stage and species of interest based on the energy and lipid storage strategies used by the fish

Spontaneous Regression of a Cystic Tumor in a Postpartum Woman; Is It A Cystic Lymphangioma?

Spontaneous regression of intra-abdominal cystic tumors in adults is unusual. Here, we present the case of an apparently spontaneous regression of a large intra-abdominal cystic mass found in the postpartum period of an 18-year-old woman. The regression was demonstrated using serial computed tomography (CT) examinations over a two-year period

The Genetic Origins of the Andaman Islanders

Mitochondrial sequences were retrieved from museum specimens of the enigmatic Andaman Islanders to analyze their evolutionary history. D-loop and protein-coding data reveal that phenotypic similarities with African pygmoid groups are convergent. Genetic and epigenetic data are interpreted as favoring the long-term isolation of the Andamanese, extensive population substructure, and/or two temporally distinct settlements. An early colonization featured populations bearing mtDNA lineage M2, and this lineage is hypothesized to represent the phylogenetic signal of an early southern movement of humans through Asia. The results demonstrate that Victorian anthropological collections can be used to study extinct, or seriously admixed populations, to provide new data about early human origins

Selection strategies for controlling muscle lipid content recorded with a non-destructive method in European whitefish, Coregonus lavaretus

Genetic selection to control lipid deposition in fish offers a valuable means to improve production efficiency and product quality. However, destructive measuring of lipid traits is a fish welfare and logistical issue due to the need for sacrificing fish, which also prevents selection on breeding candidates. We, firstly, validated the reliability of a non-invasive device with recording error, Distell Fish Fatmeter, for European whitefish (Coregonus lavaretus) by assessing the number of repeated records needed per individual, and by determining a predictive equation, which transforms Distell readings to muscle lipid% values. Secondly, using a split-family design, we estimated genetic (co)variances for the predicted muscle lipid% recorded in production environment (PE) in autumn, and in breeding nucleus (NUC) in autumn and again in the following spring. Thirdly, accuracy of selection on muscle lipid% in PE was evaluated by simulating alternative measurement strategies where: muscle lipid% was recorded either from sibs in PE (autumn) or from the breeding candidates in NUC (autumn or spring), or in both environments. Four repeated records per individual was sufficient for obtaining an accurate mean observation for an individual, though the repeatability of measurements varied somewhat between year classes (r =0.7–0.9). Heritability for muscle lipid% was high and of the same magnitude in PE (h2 ± SE=0.55 ± 0.07) and NUC (0.48 ± 0.09 in autumn, 0.49 ± 0.11 in spring). Genetic correlation between the environments was higher when the muscle lipid% was recorded in autumn (rG ± SE= 0.78 ± 0.12), compared to when recorded for NUC in spring (0.72 ± 0.12). The rG of muscle lipid% between autumn and spring measurements within NUC was 0.99 ± 0.01, indicating no genotype reranking in time over the winter. Selection accuracy was improved 14–16% by shifting from PEautumn to the strategies involving both environments and allowing exploitation of within-family genetic variation. Instead, compared to PEautumn, the strategies NUCautumn and NUCspring reduced accuracy by 7% and 17%, respectively, highlighting the importance of sib measurements in PE. There was substantial between-environment heterogeneity in both genetic and residual variation. However, the changes in accuracies were small when this heterogeneity was removed in additional calculations. In conclusion, Distell meter is a suitable tool for selecting muscle lipid% in a large number of whitefish.201