Whole-body Content Research Articles

Effect of dietary lipid levels on body compositions, digestive ability and antioxidant parameters of common carp

This study was designed to evaluate the effect of dietary lipid level on body composition, and digestive ability of common carp with initial average weight (36.12 ± 1.18)g. Five experimental diets with increasing lipid levels of 2.1%, 4.0%, 5.8%, 7.6%, 9.4% were fed to triplicate groups of fish for 9 weeks. The results showed that lipid content of whole body and muscle increased in parallel with the increase of dietary lipid levels. Protein content of muscle decreased with the increase of dietary lipid levels, and the lowest muscle protein content was observed in fish fed 9.4% lipid diet. Lipaseactivity was significantly affected by dietary lipid levels in hepatopancreas andintestine (P <0.05). Lipase activity in fish fed at 5.8% lipid level group was significantly higher than others inhepatopancreas (P <0.05). There were no significant differences in amylase and proteaseactivities (P > 0.05). The results suggested that the most excellentdigestive ability and antioxidant parameters were obtained at 7.6% lipid level group.

Genetic accommodation via modified endocrine signalling explains phenotypic divergence among spadefoot toad species

Phenotypic differences among species may evolve through genetic accommodation, but mechanisms accounting for this process are poorly understood. Here we compare hormonal variation underlying differences in the timing of metamorphosis among three spadefoot toads with different larval periods and responsiveness to pond drying. We find that, in response to pond drying, Pelobates cultripes and Spea multiplicata accelerate metamorphosis, increase standard metabolic rate (SMR), and elevate whole-body content of thyroid hormone (the primary morphogen controlling metamorphosis) and corticosterone (a stress hormone acting synergistically with thyroid hormone to accelerate metamorphosis). In contrast, Scaphiopus couchii has the shortest larval period, highest whole-body thyroid hormone and corticosterone content, and highest SMR, and these trait values are least affected by pond drying among the three species. Our findings support that the atypically rapid and canalized development of S. couchii evolved by genetic accommodation of endocrine pathways controlling metamorphosis, showing how phenotypic plasticity within species may evolve into trait variation among species.

Green seaweed Ulva sp. as an alternative ingredient in plant-based practical diets for Pacific white shrimp, Litopenaeus vannamei

In our previous research, the supplementation of Ulva sp. seaweed meal in shrimp feeds as a replacement for fish meal (FM) resulted in growth depression. To understand the factors causing the growth reduction and explore the effects of the seaweed meal as a substitution for soybean meal (SBM), a series of growth trials were conducted in the present study. Shrimp (initial mean weight 0.24, 0.15, and 0.98 g in trials 1–3, respectively) were stocked at 10 shrimp per tank (n = 4) and offered diets for 5 to 6 weeks. In trial 1, FM level was fixed and SBM was replaced using incremental level of the second batch Ulva meal (UM2). Two additional diets were formulated to allow comparison of high inclusion levels of seaweed meal from three batches (UM1–3). Results confirmed reductions in performance as replacement of SBM by Ulva meal was increased. This data also demonstrated significant difference between batches of the Ulva meal with the UM2 producing the poorest results. To elucidate if digestible protein was limiting growth, in trial 2 feeds were formulated on an equal digestible protein basis. At the end of trial 2, shrimp fed with diets containing UM2 exhibited significantly reduced growth performance, survival, and lipid content of whole shrimp body as well as increased feed conversion ratio (FCR) compared to the reference diet. Although performance of shrimp was depressed in the treatments containing UM1 and UM3, this was less than that of trial 2, indicating that protein quality may be part of the problem. Given the level of protein replacement, other components of Ulva meal are likely to be causing poor performance. A third trial was performed to evaluate the potential of the fourth batch Ulva meal (UM4) containing relatively higher protein content than the first three batches. In this trial, the growth, survival, and lipid content of whole shrimp body also decreased as the level of UM4 was increased. To survey possible problems caused by high levels of minerals, the meals and select diets were analyzed for mineral content. Clearly there are shifts in mineral profiles; however, there is no obvious correlation to a mineral. Other possible reasons would include anti-nutrients present in the algae. If Ulva meals are to be used to their full potential, e.g., as a primary protein source, the anti-nutritional components will need to be identified, specific lines of plants with enhanced nutrient value need to be developed and of course processing technologies evaluated to produce a high quality commercial product.

Evaluation of a novel bacterial biomass as a substitution for soybean meal in plant‐based practical diets for Pacific white shrimp Litopenaeus vannamei

Three growth trials and a digestibility trial were designed to evaluate the efficacy of a novel bacterial biomass (BB) in commercial-type feed formulation for Pacific white shrimp, Litopenaeus vannamei. In trial 1, the basal diet was supplemented with 0, 60 and 120 g/kg BB to replace soybean meal (SBM). Significant improvement was observed in the survival when BB was incorporated in the diets. However, shrimp fed diets containing 120 g/kg BB exhibited significantly lower weight gain (WG) and higher feed conversion ratio (FCR). To confirm the results from trial 1 and explore the effects of BB supplementation at low levels, the basal diet was incorporated with 0, 10, 20, 40, 60 and 120 g/kg BB to replace SBM in trial 2. Significant reductions in WG, FCR, lipid content of whole body, protein retention efficiency and most amino acids retention efficiency were detected in shrimp fed with diet containing 120 g/kg BB. Trial 3 was designed to elucidate whether the digestible protein is the cause of reduced growth. No improvements in terms of growth performance and FCR were detected in the treatments balanced for digestible protein. Apparent digestibility coefficients of energy, protein and amino acid (AA) for BB were determined using chromic oxide as an inert marker and the 70:30 replacement technique. The energy, protein and individual amino acid digestibility coefficients of BB were significantly lower than those of fish meal (FM) and SBM that were given at the same time. Results of this study indicated that BB can be utilized up to 40 g/kg in shrimp feed without causing a decrease in growth. However, supplementations (≥60 g/kg) of BB can result in negative effects on growth response, FCR and protein as well as amino acids retention efficiency. At the lower levels of inclusion, shrimp performance was improved when BB was supplemented on a digestibility basis; however, at the higher level of inclusion, there was no improvement, indicating there may be other nutrients limiting. Based on enhanced survival in the treatment with BB supplementation in trial 1, further research regarding the immune effects of BB in practical shrimp feed will be necessary.

Effects of conjugated linoleic acid on growth, body composition, antioxidant status, lipid metabolism and immunity parameters of juvenile Chu's croaker,Nibea coibor

A-56 days feeding trial was conducted to evaluate the growth performance, feed utilization, biochemical composition, antioxidant status, lipid metabolism and immunity parameters of Chu's croaker Nibea coibor fed diets supplemented with different levels of conjugated linoleic acid (CLA): 0% (control), 0.5%, 1%, 1.5% and 2%. Each diet was randomly assigned to triplicate groups of 25 fish (initial body weight: 12.8 ± 0.1 g) in 15 floating cage. Weight gain (WG) and specific growth rate (SGR) were not significantly affected. 2% of dietary CLA led to significant lower lipid content in both whole body and liver (p < .05). Muscle lipid content was significantly lower in fish fed 1.5% and 2% CLA (p < .05). Saturated fatty acid (SFA) increased while monounsaturated fatty acid (MUFA) decreased with increasing dietary CLA in tissues (p < .05). Increasing CLA significantly promoted hepatic lipase (HL), lipoprotein lipase (LPL), serum lysozyme (LSZ) and immunoglobulin M (IgM) while decreased serum triglyceride (TG) in both liver and serum (p < .05). Liver Superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (t-AOC) increased while malondialdehyde (MDA) decreased (p < .05). Our study shown that Chu's croaker can successfully incorporate CLA in tissues up to 2% dietary lipid without growth inhibition, and that CLA increased fish quality due to the increased parameters of lipid metabolism, specific immunity, hepatic antioxidant and CLA accumulation, and the reduction of tissue fat deposition.

P.14 - Testosterone therapy in patients with Duchenne muscular dystrophy and glucocorticoid-induced pubertal delay

Glucocorticoid therapy slows disease progression in Duchenne muscular dystrophy (DMD), but causes significant adverse effects, including delayed puberty or hypogonadism, obesity, insulin resistance and osteoporosis. Lack of puberty or hypogonadism further increases risk for osteoporosis and affects quality of life, but is not consistently addressed in DMD care. We sought to determine if testosterone therapy could induce puberty, and to examine the effects of testosterone therapy on body composition, bone health and metabolic indices, in glucocorticoid-treated patients with DMD. We reviewed medical records of boys with DMD on long-term glucocorticoid therapy, who were treated with testosterone for delayed (n = 31) or arrested (n = 2) puberty. Outcomes of interest were endogenous pubertal development; changes in body composition; bone mineral density and content of lumbar spine, whole body and lateral distal femur by dual-energy X-ray absorptiometry; and metabolic laboratory indices. Changes in bone health measures within 2.5 years prior to treatment were compared to changes up to 2.5 years after treatment initiation. Thirty-three male patients (median age 15.0 years, 27% ambulatory) on glucocorticoid therapy (median duration 7.7 years) were treated with testosterone therapy for a median of 37 (range 4.1 to 73.5) months. Endogenous puberty developed in 45% of previously pre-pubertal boys after starting testosterone. We observed increases in spine and whole body absolute bone mineral content (p = 0.03 and 0.0002 respectively), and stabilization of fat mass and percentage of total body fat accrual, when comparing post- to pre-testosterone treatment initiation. Although longer-term data are needed, testosterone therapy should be considered in the management of glucocorticoid-treated male patients with DMD who experience delayed puberty.

Dietary phospholipids requirement of the early juvenile (C1) swimming crab,Portunus trituberculatus

A 30-day experiment was conducted to investigate the effect of phospholipids (PLs) on growth performance, survival, fatty acid profile and gene expression of the early juvenile (C1) swimming crab (Portunus trituberculatus). Five semi-purified diets were formulated with graded PLs levels (0%, 1%, 2%, 4% and 8%). Each diet was fed to four replicates of crabs (30 crabs per replicate, initial weight: 8.4 ± 0.1 mg). In this study, crabs fed diets with 2%, 4% and 8% PLs had significantly higher survival rates than crabs fed with 0% and 1% PLs. Crabs fed diets with 0% and 1% PLs had significant lower weight gain (WG) than crabs fed with 8% PLs. But crabs fed with diets containing 2%, 4% and 8% PLs showed no significant difference in WG. Besides, the content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in whole body was higher than that in diets, but the monounsaturated fatty acids (MUFA) content showed an opposite trend. The EPA and DHA content in whole body increased with the increase in dietary PLs. Moreover, the moulting number increased with the increasing dietary PLs levels, the lowest moulting number was observed in crabs fed diets without supplementation of PLs. The ecdysteroid receptor (EcR) was found to be significantly up-regulated by PLs levels. This study demonstrated that 2% PLs could meet the requirement of early juvenile (C1) swimming crab based on the growth and survival. And 4%–8% PLs supplemented in diets could reduce the leaching of feed.

Effects of supplemental phytic acid on the apparent digestibility and utilization of dietary amino acids and minerals in juvenile grass carp (Ctenopharyngodon idellus )

A feeding trial was conducted for 8 weeks to evaluate the effects of supplemental phytic acid (PA) on the apparent digestibility and utilization of dietary amino acids (AAs) and minerals in juvenile grass carp. Five experimental diets consisted of graded levels of PA (0.2, 4.7, 9.5, 19.1 and 38.3 g kg−1, named as P0, P5, P10, P20 and P40). Triplicate groups of fish (initial weight, 22.37 ± 0.16 g) were fed twice daily (08:00 and 16:00 h). The crude protein content in whole body significantly (p 4.7 g kg−1) significantly reduced the apparent digestibility coefficient (ADC) of AAs (Asp, Thr, Ser, Glu, Gly, Ala, Cys, Val, Met, Ile, Leu, Phe, Lys, Pro, His and Arg) and the ADC of minerals (P, Ca, Mg, Zn, Cu, Fe and Mn) in grass carp. The contents of minerals (P, Ca, Mg and Zn) in whole body and bone were also found to be significantly reduced in dietary PA > 4.7 g kg−1, while the bone ash, serum Alkp and Zn contents were found to be significantly decreased when the PA supplementation level was above 9.5 g kg−1, and the contents of serum Ca and Mg were found to be markedly altered in higher PA-supplemented groups. The results indicated that supplemental PA decreased the apparent digestibility and utilization of AAs and minerals, and thus reduced the feed utilization of grass carp, suggesting that the level of total PA should be below 4.7 g kg−1 in grass carp diet.

Evaluation of the red alga Gracilaria lemaneiformis and brown alga Sargassum horneri as ingredients in diets for white spotted snapper Lutjanus stellatus Akazaki juveniles

This study evaluated the red alga Gracilaria lemaneiformis and brown alga Sargassum horneri as ingredients to partially replace fishmeal in diets for white spotted snapper Lutjanus stellatus Akazaki (initial mass 12.0 ± 0.1 g). Nine test diets containing 0 (control), 5, 10, 15, and 20% G. lemaneiformis or S. horneri were prepared; each diet was assigned to triplicate groups of fish in a total of 27 floating sea cages (each cage contained 30 fish). After a 60-day feeding trail, significantly lower final body weight, weight gain, and specific growth ratio were found in fish fed 20% G. lemaneiformis diet (P < 0.05), whereas the poorest fish growth performance was obtained with the 20% S. horneri diet. Lipid content in muscle of fish fed 20% G. lemaneiformis diet was significantly lower than that of other groups (P < 0.05); however, body protein was higher than that in other groups. The lowest lipid and moisture contents in muscle were recorded in fish fed 5 and 15% S. horneri diets, and protein content in whole body of fish fed 20% S. horneri diet was significantly lower than that of control and 5% diets (P < 0.05). Activities of pepsin in the stomach and lipase and amylase in the intestine were significantly suppressed in fish fed 20% G. lemaneiformis diet compared with that of control (P < 0.05). The lowest pepsin activity in stomach and lipase activity in intestine were observed in fish fed 20% S. horneri diet. Based on a quadratic regression model of weight gain, the results suggested that the maximum incorporation of G. lemaneiformis and S. horneri in diets should be 16.44 and 15%, respectively, for juvenile white spotted snapper.

Evaluation of dried fermented biomass as a feed ingredient in plant-based practical diets for juvenile Pacific white shrimp Litopenaeus vannamei

Two growth trials were designed to evaluate the utilization of dried fermented biomass (DFB) in commercial type feed formulation for Pacific white shrimp, Litopenaeus vannamei. In trial 1, four experimental diets were formulated to utilize increasing levels (0, 25, 50 and 100 g/kg) of spray-dried fermented biomass (SDFB) as a replacement of fish meal (FM). Results indicated that SDFB can be utilized up to 50 g/kg as a substitution for FM without causing growth depression in shrimp. However, dietary SDFB supplementation at 100 g/kg significantly reduced the weight gain (WG) of shrimp and increased feed conversion ratio (FCR). This reduction in performance is likely due to palatability or nutrient imbalances of the feed. In trial 2, nine experimental diets were formulated with increasing levels (0, 20, 40, 60 and 120 g/kg) of spray-dried (S) or granular (G) DFB to replace soy protein concentrate (SPC) or SPC + corn protein concentrate (CPC). This allowed the comparison between spray-dried and ring-dried products. Ring drying produced a granular product, reducing dust and increasing product particle size. Shrimp fed with diet containing 20 g/kg GDFB performed the best in terms of final mean weight, WG and FCR. Significantly reduced growth and increased FCR were observed in shrimp fed diets containing 60 and 120 g/kg SDFB. Lipid content of whole body was significantly reduced when GDFB was incorporated at 120 g/kg. No significant differences were detected in survival, protein retention efficiency as well as protein and ash contents of the whole shrimp. Results from analysis of covariance indicated that the processing method (covariant) had a significant effect on final mean weight, WG and FCR. In general, shrimp fed with diet containing granular product performed better as compared to those fed with diets utilizing spray-dried product. GDFB can be utilized in the diets up to 120 g/kg in practical shrimp feeds as a substitute for SPC and CPC without compromising the growth of shrimp. However, a significant reduction in WG was observed in the diets containing 60 and 120 g/kg SDFB. The results in the current study demonstrate that processing changes to produce a granular product produced an improved feed ingredient for shrimp.

Interactive effects of dietary leucine and isoleucine on growth, blood parameters, and amino acid profile of Japanese flounder Paralichthys olivaceus.

A 60-day feeding trial was conducted to assess the interactions of dietary leucine (Leu) and isoleucine (Ile) on Japanese flounder. Fish of 2.69±0.04g were fed experimental diets containing two levels of Leu (2.58 and 5.08% of diet) combined with three levels of Ile (1.44, 2.21, and 4.44% of diet), respectively. After the feeding trial, growth, proximate composition, muscle total amino acid profile, blood parameters, mucus lysozyme activity, and stress tolerance to freshwater were measured. Statistically significant (P<0.05) interactive effects of Leu and Ile were found on growth parameters (final body weight, body weight gain, and special growth rate) of Japanese flounder. Antagonism was discovered in high dietary Leu groups, while stimulatory effects were obtained for increased dietary Ile in low Leu groups. Interactive effects of these two branched-chain amino acids were also found on hepatosomatic index of test fish. In addition, crude lipid content of fish whole body was significantly altered by various diets, with antagonism observed in low dietary Leu groups. Interactive effects also existed in muscle amino acid profiles for low fish meal diets, but no interactive impacts were observed on blood parameters. Furthermore, lysozyme activities and freshwater stress were significantly affected by different diets. And antagonism was found on lysozyme activities in low Leu groups. Moreover, high Leu and high Ile levels of diet significantly altered freshwater stress tolerance of Japanese flounder. These findings suggested that dietary Leu and Ile can effect interactively, and fish fed with diets containing 2.58% Leu with 4.44% Ile and 5.08% Leu with 1.44% Ile showed better growth performance.

Replacing the substitute-Guar meal as an alternative for non-genetically modified soybean meal in the nutrition of rainbow trout (Oncorhynchus mykiss , Walbaum, 1792)

Soybean meal (SBM) is widely used in aqua feed products. In the European Union, only non-genetically modified (non-GM) SBM is accepted. However, global production of non-GM soybeans is declining and is limiting its utilization in aqua feeds. Therefore, non-GM SBM alternatives are required. In this study, guar meal was evaluated as a substitute for non-GM SBM in test feeds for rainbow trout (Oncorhynchus mykiss). Fish (initial weight of 57 ± 10.1 g) were stocked to 12 experimental tanks of a freshwater recirculation system with a stocking density of 6 kg/tank (500 L). Fish were organized in triplicate groups and received isonitrogenous and isocaloric experimental feeds designated as control and test feeds 1–3, where 0, 50, 100 and 150 g/kg feed of non-GM SBM was replaced by guar meal. During the experimental test period of 56 days, fish were fed twice a day until apparent satiation. Compared to the control group, daily feed intake of test feeds 1–3 was significantly increased by guar meal inclusion. No significant differences in feed conversion ratio and specific growth rate were detected among all the treatments. Furthermore, guar meal inclusion did not affect protein efficiency ratio. However, protein productive value was significantly impaired when guar meal incorporation was above 100 g/kg feed. In accordance with the affected protein productive value, the crude protein content of the proximate whole fish body declined significantly. In contrast, condition factor, hepatosomatic index, slaughter yield and fillet yield provided no significant differences between the experimental groups. In conclusion, this study demonstrated that non-GM SBM could be entirely replaced by guar meal without affecting the general performance of fish and suggests guar meal as an appropriate alternative for non-GM SBM in the nutrition of rainbow trout.

Evaluation of flash dried yeast as a nutritional supplement in plant-based practical diets for Pacific white shrimp Litopenaeus vannamei

Growth and digestibility trials were conducted to evaluate the use of flash dried yeast (FDY) as a supplement in practical shrimp feeds. The six-week growth trial evaluated the effects of FDY supplementation (0, 10, 20, 40 and 60 g kg–1) in the plant-based practical diet on the performances and proximate compositions of juvenile Pacific white shrimp, Litopenaeus vannamei. Final biomass, final mean weight, per cent weight gain (WG), feed conversion (FCR) and protein retention efficiency (PRE) of Pacific white shrimp were not significantly influenced when FDY was added up to 40 g kg–1 of the diet. However, 60 g kg–1 FDY supplementation significantly reduced growth, feed utilization and protein retention. Supplementation of FDY in the practical diets of Pacific white shrimp did not affect protein, moisture, lipid, crude fibre, and ash content of whole shrimp body. Apparent digestibility coefficients of energy, protein, and amino acid (AA) for FDY were determined using chromic oxide as an inert marker and the 70:30 replacement technique. The energy and protein digestibility of FDY were 38.20% and 53.47%, respectively, which were significantly lower than fishmeal (FM) and soybean meal (SBM) that were run at the same time. Most amino acid digestibility of FDY was lowest among the three ingredients tested. Results of this work indicated that energy, protein and amino acid digestibility of FDY are lower compared to SBM and FM, and high levels supplementation (≥60 g kg–1) of FDY can cause negative effects to the growth response of Pacific white shrimp. Based on these results, further research regarding the effects of the low level inclusion of FDY in practical diets on immune responses of Pacific white shrimp is warranted.

Dietary Lipid Sources Influence Fatty Acid Composition in Tissue of Large Yellow Croaker (Larmichthys crocea) by Regulating Triacylglycerol Synthesis and Catabolism at the Transcriptional Level.

An 8-week feeding trial was conducted to evaluate the effects of dietary lipid sources on growth performance, fatty acid composition, rate-limiting enzyme activities and gene expression related to lipid metabolism in large yellow croaker (Larmichthys crocea). Five iso-nitrogenous and iso-lipidic experimental diets were formulated to contain different lipid sources, such as fish oil (FO), soybean oil (SO), linseed oil (LO), rapeseed oil (RO) and peanut oil (PO), respectively. Triplicate groups of 50 fish (initial weight 13.77±0.07g) were stocked in 15 floating net cages (1.5m×1.5m×2.0m). Fish fed the diets containing RO and LO had lower weight gain and specific growth rates than those fed the FO, SO and PO diets. Survival, feed efficiency, protein efficiency ratio, hepatosomatic index, viscerasomatic index and condition factor were not significantly affected by different dietary lipid sources. Fish fed the diet containing FO had higher lipid content in whole body compared with the other groups, whereas fish fed the SO diet had the lowest muscle lipid content. Fatty acid profiles of muscle and liver reflected the fatty acid composition of the diets. Plasma glucose, triglyceride, and the enzymatic activity of aspartate aminotransferase and alanine aminotransferase were significantly influenced by different dietary lipid sources, while total protein, cholesterol, superoxide dismutase or malondialdehyde in plasma were not affected by the different dietary lipid sources. Fish fed the LO diet had lower adipose triglyceride lipase and fatty acid synthase activities in liver than those fed the diets containing FO and RO, while the LO diet resulted in the highest hepatic carnitine palmitoultransferase-1 activity. Hepatic gene relative expression of adipose triglyceride lipase and carnitine palmitoyltransferase-1 in fish fed PO diet was significantly higher than all other groups, whereas fish fed the SO and LO diets had lower relative expression levels of lipoprotein lipase than the other groups. The highest relative expression levels of fatty acid synthase and acyl-CoA diacylglycerol acyltransferase-2 were observed in the FO group, while the highest relative expression of glucose 6-phosphate dehydrogenase occurred in fish fed the FO and RO diets. In summary, based on the growth performance, FO and SO appear to be suitable lipid sources for large yellow croaker, with the findings of this study also providing a molecular insight into the role of lipid metabolic mechanism in response to different dietary lipid sources.

Early Intake of Radiocesium by Residents Living Near the TEPCO Fukushima Dai-Ichi Nuclear Power Plant after the Accident. Part 1: Internal Doses Based on Whole-body Measurements by NIRS.

The Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in 2011 resulted in a release of radionuclides into the environment (I: 142.9 PBq, Cs:12.4 PBq). This study presents the results of internal doses to 174 residents living near the FDNPP at the time of the accident based on whole-body (WB) measurements performed by the National Institute of Radiological Sciences (NIRS) during the period between 27 June and 28 July 2011. The 174 subjects consisted of 125 adults (≥18-y) and 49 children (<18-y) and included 90 persons of Namie town, one of the municipalities heavily contaminated with the radionuclides. The number of subjects with significant detection of both Cs and Cs was relatively small: 28.8% for the adults and 4.1% for the children. A significant gender difference in the Cs detection rate (males > females) was observed in the adults but not the children. In this study, the committed effective dose (CED) from Cs and Cs was calculated based on individual WB contents (Cs) corrected against body size, the observed body content ratio of Cs to Cs, and the assumed intake scenario (namely, acute inhalation of Type F compounds on 12 March 2011 when the first explosive event occurred at the site of the FDNPP). The 90th-percentile CED value for the adults was around 0.1 mSv and the maximum CED (0.63 mSv) was found in an elderly male. Comparable CED results were obtained in other WB measurements subsequently performed by the Japan Atomic Energy Agency (JAEA) in a similar manner to that of the NIRS, suggesting that the contribution of ingestion to the WB content observed would be trivial for most of the JAEA subjects. The intake ratio of I to Cs was evaluated to be 3~5 based on the I thyroid measurement data of Tokonami et al. Using the average intake ratio of 3.8, the resulting median and maximum thyroid-equivalent doses to the adult subjects of this study were estimated at 3.5 mSv and 84 mSv, respectively.

Life-cycle exposure to BDE-47 results in thyroid endocrine disruption to adults and offsprings of zebrafish (Danio rerio).

2,2,4',4'-Tetrabromodi-phenyl ether (BDE-47) is predominantly concentrated in humans and wildlife and disturbs thyroid hormone homeostasis. The purpose of this study was to characterize the thyroid endocrine disruption induced by life-cycle exposure to BDE-47 in adults and offspring of zebrafish (Danio rerio). We exposed zebrafish embryos at the blastula stage to different concentrations of BDE-47 (1, 5, and 10μg/L). Exposure duration was 180days until fish reached adulthood. In F0 larvae, exposure decreased survival and increased malformations at 4 dpf. Thyroid hormone concentrations did not differ significantly between the F0 larvae and controls. All exposures significantly up-regulated expression of tshß, pa8, ugt1 and tg and down-regulated ttr. Significant up-regulation of dio2 and crh was observed in the 10μg/L BDE-47 group. There was no significant difference in the growth and somatic index between F0 adults and controls. BDE-47 (10μg/L) significantly decreased whole-body content of thyroxine (T4) but significantly increased triiodothyronine (T3) in both sexes. All exposures up-regulated expression of crh, tshß, pa8, ugt1 and tg and down-regulated ttr. Exposure to 10μg/L BDE-47 significantly up-regulated dio2 and ugt1 in both sexes. BDE-47 exposure (5 and 10μg/L) significantly increased the activity of pethoxy-resorufin-O-deethylase and UDP-glucuronosyl transferase. BDE-47 (10μg/L) significantly increased activity of ethoxy- and methoxy-resorufin-O-deethylase. In F1 offspring without continued BDE-47 (10μg/L) treatment, T4 significantly decreased and T3 increased. T4 was further decreased and T3 was further increased with continued BDE-47 treatment. Continued BDE-47 exposure decreased hatching and increased malformation compared with those without BDE-47 exposure. Expression of crh, tshß, dio2, pa8, ugt1 and tg was significantly up-regulated without BDE-47 exposure and with continued exposure. With continued BDE-47 exposure, dio1 was significantly up-regulated and ttr was significantly down-regulated. All the genes showed clear differences between continued exposure to 10μg/L BDE-47 and without BDE-47 exposure. These results suggest that parental exposure to BDE-47 results in thyroid endocrine disruption in adults and offspring.

Partial replacement of fish-meal by soy protein concentrate and soybean meal based protein blend for juvenile Pacific white shrimp, Litopenaeus vannamei

An 8-week feeding trial was conducted to evaluate the effect of fish-meal replacement on growth performance, whole body composition, apparent digestibility coefficients and anti-oxidative ability of juvenile Pacific white shrimp, Litopenaeus vannamei. Five practical diets were formulated to contain graded levels (5, 10, 15, 20 and 25%) of fish-meal. Soy protein concentrate and soybean meal based protein blend was used to replace fish-meal, amino acids were supplemented in the low fish-meal diet to get similar amino acid profile as the high fish-meal diet. Weight gain, survival, feed conversion rate (FCR), feed intake and protein efficiency ratio (PER) did not show any significant differences between any of the groups. Alanine ratio in whole body were higher in shrimp fed high fish-meal diets while arginine decreased with the increasing fish-meal levels. The Fe content in whole body was significantly lower in shrimp fed the low fish-meal diets, while the other minerals showed no difference among all the groups. Apparent digestibility coefficients (ADC) of dry matter, protein, Ca, P, Cu, Zn and Mg were equal in all the treatments, while ADC of Fe decreased with the decreasing fish-meal levels. When dietary fish-meal decreased, the anti-oxidant related enzymes activity (Total antioxidant capacity (T-AOC) and Catalase (CAT)). Superoxide dismutase (SOD) was unaffected by treatments. Nitric oxide (NO) contents in hemolymph significantly decreased with the decreasing fish-meal levels, while Phenoloxidase (PO) was unaffected. The results indicated that growth performance and apparent digestibility coefficients of nutrients were not affected when fish-meal was replaced from 25% to 5%, but anti-oxidative ability and immune response were damaged after fish-meal level decreased to 15%. Statement of relevanceThe results of this manuscript contribute to the commercial feed industry of white shrimp, it will be helpful in fish meal replacement, which is very important to the sustainable development of aquaculture.

Growth, body composition and hepatopancreas morphology of Nile tilapia fingerlings fed crude glycerol as a replacement for maize in diets

This study consisted in determining the best level of replacement of maize by crude glycerol as an energy source for Nile tilapia fingerlings evaluating the growth performance, body composition and hepatopancreas histology. Three hundred Nile tilapia with an average weight of 11.46±2.18g were placed in 30 plastic aquaria (60L), in a completely randomized design with six treatments (levels of replacement of maize by crude glycerol at 0, 20, 40, 60, 80 and 100%) and five replications. The feeding regime consisted of three daily feedings ad libitum. An increase (P<0.05) in crude protein and body moisture, and a decrease in lipids and mineral content in whole body of fish fed with increasing levels of glycerol was observed. Regarding the productive performance hepatosomatic index showed a quadratic effect (P<0.05) and there was a linear reduction (P<0.05) in feed conversion with increasing substitution of maize by glycerol. No statistical differences were found (P>0.05) in the area of hepatocytes and no changes were observed in the morphology of the hepatopancreas. It is possible to replace totally maize by glycerol in pelleted diets for Nile tilapia fingerlings between 10 and 30g without causing prejudice to the productivity and quality of fish.

Response of juvenile Japanese seabass (Lateolabrax japonicus) to different dietary fatty acid profiles: Growth performance, tissue lipid accumulation, liver histology and flesh texture

A 10-week feeding experiment in offshore floating cages was conducted to investigate the effects of dietary fatty acid profiles on growth, tissue lipid accumulation, liver histology and flesh texture of juvenile Japanese seabass (mean initial weight 29.53±0.86g). Six low-fish meal diets were prepared with different lipid sources (10% in the diets), each with a characteristic fatty acid: Diet MCA: medium-chain fatty acid, C8:0+C10:0; Diet PA: palmitic acid, C16:0; Diet SA: stearic acid, C18:0; Diet OA: oleic acid, C18:1n−9; Diet LNA: α-linolenic acid, C18:3n−3; Diet N-3 LC-PUFA: n−3 LC-PUFA, DHA+EPA. A diet with 10% fish oil was used as the control diet (Diet FO). Each diet was fed triplicate groups of 30 fish. The results showed that the compared to group FO, the final body weight (FBW), specific growth rate (SGR) and feed efficiency ratio (FER) were significantly reduced in groups MCA, PA, and SA, but not in groups OA, LNA, and N-3 LC-PUFA. The feed intake (FI) in group MCA was much lower compared to other groups, while group PA showed the highest FI, significantly higher than that in group N-3 LC-PUFA. Diets MCA, PA, and SA leaded to much lower lipid content in muscle, gut, and whole fish body, while the liver lipid content was significantly higher in groups PA, SA, OA, and LNA than that in groups FO, MCA, and N-3 LC-PUFA. Obvious hepatocytes swelling, lipid vacuolization and nucleus polarization were observed in liver from groups OA, SA, PA, and LNA, while in group MCA, the hepatic tissue was in disorder with indistinguishable hepatic cell outline and dissolved nuclei. Fish fed MCA, PA, and SA tended to have firmer flesh than fish fed OA, LNA, and N-3 LC-PUFA. These results showed that Japanese seabass has a relatively high tolerance to oils rich in C18:1n−9 and C18:3n−3 but high levels of C16:0 or C18:0 enriched lipid sources could reduce the feed efficiency and growth rate. High levels of medium chain fatty acids (C8:0 and C10:0) in the diets could drastically reduce the feed intake. All the alternative lipid sources leaded to impairment to liver histology and modified the flesh texture, probably via altering tissue lipid concentrations. Statement of relevanceThis study provided useful data for the application of a range of alternative lipid sources in fish feed. Also, the present results are helpful in formulating a balanced dietary fatty acid profile for Japanese seabass.

Earthworms accumulate alanine in response to drought

Earthworms have ecologically significant functions in tropical and temperate ecosystems and it is therefore important to understand how these animals survive during drought. In order to explore the physiological responses to dry conditions, we simulated a natural drought incident in a laboratory trial exposing worms in slowly drying soil for about one month, and then analyzed the whole-body contents of free amino acids (FAAs). We investigated three species forming estivation chambers when soils dry out (Aporrectodea tuberculata, Aporrectodea icterica and Aporrectodea longa) and one species that does not estivate during drought (Lumbricus rubellus). Worms subjected to drought conditions (< −2MPa) substantially increased the concentration of FAAs and in particular alanine that was significantly upregulated in all tested species. Alanine was the most important FAA reaching 250–650μmolg−1 dry weight in dehydrated Aporrectodea species and 300μmolg−1 dry weight in L. rubellus. Proline was only weakly upregulated in some species as were a few other FAAs. Species forming estivation chambers (Aporrectodea spp.) did not show a better ability to conserve body water than the non-estivating species (L. rubellus) at the same drought level. These results suggest that the accumulation of alanine is an important adaptive trait in drought tolerance of earthworms in general.