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121.
l ‐ascorbyl‐2‐monophosphate‐Na/Ca (AMP‐Na/Ca) was used as a vitamin C source to investigate the ascorbic acid (AsA) requirements on growth performance and stress resistance of the post‐larval kuruma shrimp, Marsupenaeus japonicus. Purified carrageenan‐microbound diets with six levels of AMP‐Na/Ca, AsA equivalent to 0, 20, 56, 87, 759 and 1697 mg kg?1 diet were fed to triplicate groups of M. japonicus (mean initial weight 16±0.3 mg) for 30 days. The diets with AsA 0, 20 and 56 mg kg?1 showed high cumulative mortality after 10 days of feeding. After the 30‐day trial, the shrimp fed these diets had significantly lower survival and weight gain (WG, %) than those fed the 87, 759 and 1697 mg AsA kg?1 diets. Specific growth rate and individual dry weight showed the same pattern as WG (%). There were no significant differences in growth performance among the groups fed the AsA levels at 87, 759 and 1697 mg kg?1 at the termination of feeding trial. Broken‐line regression analysis indicated that 91.8 mg AsA kg?1 in the diet was the optimum for post‐larval shrimp. On the other hand, dietary level of more than 800 mg AsA kg?1 was needed to ensure high resistance to stressful conditions such as osmotic and formalin stressors.  相似文献   
122.
  1. It is essential to consider genetic composition for both conventional coral restoration management and for initiating new interventions to counter the significant global decline in living corals. Population genetic structure at a fine spatial scale should be carefully evaluated before implementing strategies to achieve self-sustaining ecosystems via coral restoration.
  2. This study investigated the population genetic structure of two acroporid species at Kume Island, Okinawa, Japan. There were 140 colonies of Acropora digitifera collected from seven study sites, and 81 colonies of Acropora tenuis from six sites. In total, 384 single nucleotide polymorphism (SNP) loci for A. digitifera and 470 SNPs for A. tenuis were obtained using a comparatively economical technique, Multiplexed ISSR Genotyping by sequencing.
  3. Observed heterozygosity was significantly lower than expected heterozygosity at all SNP sites in both acroporid species, suggesting deficient genetic diversity possibly caused by past massive coral bleaching. Even though both species are broadcast spawners, the population structure was different in the two species. No detectable structure was evident in A. digitifera, but two distinct clades were found in A. tenuis. The genetic homogeneity of A. digitifera at Kume Island suggests that this species could be used as a focal species for active restoration in terms of genetic differentiation at this island. By contrast, A. tenuis unexpectedly included two distinct clades with little or no admixture within a small study area, possibly representing two reproductively isolated cryptic species. Thus, when using A. tenuis, it would be prudent to avoid disturbing the genetic composition of wild populations until this question is answered.
  相似文献   
123.
ABSTRACT:   Using the dorsal ordinary muscle (DOM) of cultured Pacific bluefin tuna (body length [BL]: 47.5–81.8 cm, body weight [BW]: 2.1–13.5 kg, n  = 15), the changes of proximate compositions and myoglobin (Mb) content with growth were investigated. There was a positive correlation ( r  = 0.9832, P  < 0.05) of BL and BW in cultured tuna. The protein contents of the DOM of cultured tuna decreased ( P  < 0.05) and the lipid contents had a tendency to increase (not significantly) with growth. The meat color changed from pink to red with growth. In addition, the Mb contents of the DOM of cultured tuna increased ( P  < 0.05) from 1.0 mg/g (minimum BW fish) to 3.8 mg/g (maximum BW fish) with growth. These results indicate that the increase of the Mb content in the DOM of cultured tuna is not caused by the restriction of exercise and overfeeding between 2.1 kg and 13.5 kg of BW.  相似文献   
124.
A feeding trial using five semi-purified diets (50% crude protein) was conducted to investigate the effects of different dietary amino acid patterns on growth and body composition of juvenile Japanese flounder. The control diet contained casein and gelatin as intact protein sources and four other diets contained 30% casein–gelatin (2:1, w/w) and 20% crystalline amino acids (CAA). CAA were added to the diets to simulate the amino acid pattern found in red sea bream egg protein (REP), Japanese flounder larvae whole body protein (FLP), Japanese flounder juvenile whole body protein (FJP), and brown fish meal protein (BFP), respectively. The test diets were fed to triplicate groups of juveniles (2.75±0.05 g) twice a day for 40 days to evaluate weight gain, survival, feed conversion efficiency (FCE), protein efficiency ratio (PER), and apparent protein utilization (APU). The apparent retention of total dietary amino acids in the whole body and A/E ratios of the whole body were also evaluated. The highest weight gain was observed in fish fed the diet containing the dietary amino acid pattern of BFP followed by fish fed the control, FJP, FLP and the REP diets. Percent survival, FCE, PER and APU were also significantly (P<0.05) affected by the amino acid pattern in the diets, indicating the highest value in fish fed the BFP diet. Except for a few amino acids, the amino acid composition of the whole body did not show marked differences with different dietary amino acid pattern. Results suggest that BFP could be more suitable as a reference amino acid pattern in the diet of juvenile Japanese flounder compared to the amino acid pattern of FLP, FJP or REP.  相似文献   
125.
Two consecutive feeding trials were conducted to know: (i) how the apparent digestibility coefficient (ADC) varies among replicates on different days and during the course of the experiment (Trial 1); and (ii) the effect of stocking density (e.g. 7.17, 5.56, and 3.92 kg fish/t water) on the ADC of nutrients and energy in red sea bream (Trial 2). In both trials, 0.5% Cr2O3 was used as an inert marker. In Trial 1, there were no significant differences in ADC within the replicates although the values on different days varied significantly during the second week. The ADC of all parameters in the third and fourth weeks was significantly higher than in the second week (P<0.05). Although statistically insignificant, the lower stocking densities (3.92 and 5.56 kg fish/t water) showed better growth performance and superior ADC of protein, lipid, and energy than the higher stocking density in Trial 2. The results indicated that it may be better to acclimate fish to the diet for at least three weeks to obtain more reliable data by using a single tank for each treatment for digestibility experiments. Results also indicated that growth and digestibility performance can be stimulated by controlling stocking density.  相似文献   
126.
In 2010, an H5N1 highly pathogenic avian influenza virus (HPAIV) was isolated from feces of apparently healthy ducks migrating southward in Hokkaido, the northernmost prefecture of Japan. The H5N1 HPAIVs were subsequently detected in domestic and wild birds at multiple sites corresponding to the flyway of the waterfowl having stopovers in the Japanese archipelago. The Hokkaido isolate was genetically nearly identical to H5N1 HPAIVs isolated from swans in the spring of 2009 and 2010 in Mongolia, but less pathogenic in experimentally infected ducks than the 2009 Mongolian isolate. These findings suggest that H5N1 HPAIVs with relatively mild pathogenicity might be selected and harbored in the waterfowl population during the 2009-2010 migration seasons. Our data provide "early warning" signals for preparedness against the unprecedented situation in which the waterfowl reservoirs serve as perpetual sources and disseminators of HPAIVs.  相似文献   
127.
The adhesion-preventing effect of trehalose in visceral organs was evaluated in a rabbit model. All rabbits underwent a hysterotomy, during which mild abrasion and desiccation was induced on the surfaces of visceral organs. In the control group, the intestines were kept dry during hysterotomy. In the saline and trehalose groups, saline solution and 7% trehalose solution, respectively, were sprayed on the organ surfaces. Adhesion formation on organ surfaces on which abrasion and desiccation were induced declined significantly in the trehalose group compared with the other groups. In contrast, at the hysterotomy site, there was no significant difference in adhesions between groups, suggesting that trehalose prevents adhesions in organs that have developed minor inflammation by abrasion and desiccation.  相似文献   
128.
Options of systemic treatment for canine MCT have been still limited and most canine cases with MCTs eventually undergo relapses even after achievement of a remission. Thus additional therapies are required to establish for the tumor. To identify the novel candidate therapeutic targets for canine MCT, the mRNA expression and phosphorylation statuses of several receptor or non-receptor kinases as well as the inhibitory effect of 95 specific inhibitors on the growth were assessed in three canine MCT cell lines (HRMC, VIMC1 and CMMC1). Among the 14 targets, the mRNAs of 11, 7 and 7 kinases were amplified in HRMC, VIMC1 and CMMC1, respectively. The mRNAs of VEGFR3, PDGFRα, SRC, YES, LCK and FYN were detected in all cell lines. The phosphorylation of 12, 8 and 7 kinases was observed by using specific antibody arrays in HRMC, VIMC1 and CMMC1, respectively. DTK, EPHB6, AMPKα1, CREB, STAT5a and STAT5b were phosphorylated in all cell lines. The 10, 9 and 17 inhibitors exhibited the biological activity against the growth of HRMC, VIMC1 and CMMC1, respectively. Only three inhibitors such as SB218078 (for Chk1), PDGF RTK inhibitor IV (for PDGFR) and radicicol (for Hsp90) suppressed the growth of all three cell lines. The present study indicated that several kinases, such as Chk1, PDGFR and Hsp90, could be used as therapeutic targets in the treatment for canine MCT. Further studies and clinical trials are warranted to apply the inhibitors for the treatment of the tumor.  相似文献   
129.
We evaluated loop-mediated isothermal amplification (LAMP) as a means of detecting equine herpesvirus type 1 (EHV-1) DNA directly from nasal swabs. To increase the sensitivity, we added a step in which the samples were heat-treated to the original LAMP procedure. The detection limit of the LAMP assay with heat treatment was 10 times more sensitive than the original LAMP assay even when the DNA extraction step was omitted. In addition, the LAMP assay with heat treatment was more sensitive than the original LAMP assay and the polymerase chain reaction using clinical samples. The LAMP assay with heat treatment is easy to perform and so should be applicable to the diagnosis of EHV-1 infections in clinical laboratories.  相似文献   
130.
A 55-d feeding experiment was conducted to evaluate the effects of dietary vitamin A on growth of juvenile red sea bream Chrysophrys major . Nine semi-purified diets with supplemental retinol palmitate at levels of 0, 300, 600, 1,500, 3,000, 4,500, 6,000, 15,000 and 30,000 retinol eq/kg diet, were fed twice daily to triplicate groups of 10 juveniles per tank with an initial weight of 1.178 ± 0.001 g. Weight gain and specific growth rate increased with the increase of supplemental retinol palmitate in the diet up to a level of 6,000 retinol eq/kg diet, beyond which those indices tended to decrease slightly or to plateau. Significantly lower weight gain and specific growth rate were observed in fish fed with 0 and 300 retinol eq/kg diet. No significant differences were found in survival rates among the different levels of supplementation. The crude protein, lipid, moisture and ash contents in the whole body were not affected by the different vitamin A supplemental levels. Besides the reduced growth, fish fed with low levels of vitamin A supplement showed no other signs of deficiency. No hypervitaminosis A symptoms were observed in fish fed on high levels of supplementation. Fish fed on diets with 0 and 300 retinol eq/kg diet showed a significantly lower content of vitamin A (as a total retinol) in the liver than those in groups fed with higher levels of supplementation. Vitamin A was stored in the liver mainly as retinyl esters. Total retinal content of the eye showed no significant differences among the treatments; however, fish fed with 0 and 300 retinol eq/kg of diet had slightly higher concentrations. According to the results of the mean weight gain, specific growth rate and liver retinol content, the requirement of dietary vitamin A for juvenile red sea bream was estimated to be between 1,500 and 6,000 retinol eq/kg.  相似文献   
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