Optimization of dose of methyltestosterone (MT) hormone for sex reversal in tilapia (Oreochromis niloticus L.)

This paper describes the optimization of dose of methyltestosteronei (MT) hormone for masculinization of tilapia (Oreochromis niloticus). Five treatments (i.e. T1 T2, T2, T4 and T5) with different doses such as 0, 40, 50, 60 and 65 mg of MT hormone were mixed with per kg of feed for each treatment and fed the fry four times a day up to satiation for a period of 30 days. The stocking density was maintained 10 spawn/liter of water. The growth of fry at different treatments was recorded weekly and mortality was recorded daily. At the end of hormone feeding the fry were reared in hapas fixed in ponds for another 70 days and at the 100th day the fish were sexed by the gonad squashing and aceto-carmine staining method. The analysis of growth data did not show any significant variation in length and weight of fish among the different treatments. High mortality of fry ranging 66% to 81.6% was observed in different treatments and highest mortality was observed during the first twelve days of the experiment. The sex ratio analysis showed that T2 (40 mg/kg) and T5 (65 mg/kg) produced 93.33% of sex reversed male and T3 (50 mg/kg) and T4 (60 mg/kg) produced 96.66% sex reversed male, and these ratios were significantly (p<0.05) different from 1:1 male: female sex ratio. The control, T1 (0 mg/kg) contained 43.33% male progeny. From these results it is suggested that either 50 mg/kg or 60 mg/kg of MT with a feeding period of 30 days could be considered as an optimum dose for masculinization of tilapia (O. niloticus)

Soybean Amino Acids in Health, Genetics, and Evaluation

Soybean is an important source of protein and amino acids for humans and livestock because of its well-balanced amino acid profile. This chapter outlines the strengths and weaknesses of soybean as a complete amino acid source as well as the relative importance of individual amino acids. Special attention is paid to the sulfur-containing amino acids, methionine and cysteine. Breeding and genetic engineering efforts are summarized to highlight previous accomplishments in amino acid improvement and potential avenues for future research. Agronomic properties and processing methods that affect amino acid levels in soybean food and feed are also explained. A brief introduction into current amino acid evaluation techniques is provided. By understanding the complexities of amino acids in soybean, protein quality for humans and livestock can be maximized

Comparative Analysis Carried Out on Modern Indentation Techniques for the Measurement of Mechanical Properties: A Review

Nowadays many indentation techniques are being commonly employed for determining some mechanical properties (harness, elastic modulus, toughness, etc.) using simple method of measuring the indentation depth. On the basis of measurement of depth of penetration, indentation technique has be classified into major categories i.e. microindentation and nanoindentation. Nanoindentation technique uses indirect method of determining the contact area as the depth of penetration is measured in nanometers, while in conventional indentation the area in contact is measured by elementary measurement of the residual area after the indenter is removed from the specimen. Dynamic hardness is the best result of dynamic indentation which can be expressed as the ratio of energy consumed during a rapid indentation to the volume of indentation. The parameter which are taken into consideration are indentation depth, contact force, contact area, mean contact pressure

Discrimination based on Gly and Arg/Ser at position 673 between dipeptidyl-peptidase (DPP) 7 and DPP11, widely distributed DPPs in pathogenic and environmental gram-negative bacteria

Porphyromonas gingivalis, an asaccharolytic gram-negative rod-shaped bacterium, expresses the novel Asp/Glu-specific dipeptidyl-peptidase (DPP) 11 (Ohara-Nemoto, Y. et al. (2011) J. Biol. Chem. 286, 38115–38127), which has been categorized as a member of the S46/DPP7 family that is preferential for hydrophobic residues at the P1 position. From that finding, 129 gene products constituting five clusters from the phylum Bacteroidetes have been newly annotated to either DPP7 or DPP11, whereas the remaining 135 members, mainly from the largest phylum Proteobacteria, have yet to be assigned. In this study, the substrate specificities of the five clusters and an unassigned group were determined with recombinant DPPs from typical species, i.e., P. gingivalis, Capnocytophaga gingivalis, Flavobacterium psychrophilum, Bacteroides fragilis, Bacteroides vulgatus, and Shewanella putrefaciens. Consequently, clusters 1, 3, and 5 were found to be DPP7 with rather broad substrate specificity, and clusters 2 and 4 were DPP11. An unassigned S. putrefaciens DPP carrying Ser673 exhibited Asp/Glu-specificity more preferable to Glu, in contrast to the Asp preference of DPP11 with Arg673 from Bacteroidetes species. Mutagenesis experiments revealed that Arg673/Ser673 were indispensable for the Asp/Glu-specificity of DPP11, and that the broad specificity of DPP7 was mediated by Gly673. Taken together with the distribution of the two genes, all 264 members of the S46 family could be attributed to either DPP7 or DPP11 by an amino acid at position 673. A more compelling phylogenic tree based on the conserved C-terminal region suggested two gene duplication events in the phylum Bacteroidetes, one causing the development of DPP7 and DPP11 with altered substrate specificities, and the other producing an additional DPP7 in the genus Bacteroides

Comparison of growth performance between cryopreserved and fresh sperm-originated fry of Barbonymus gonionotus

This experiment was conducted to compare the growth performance of silver barb fry produced from cryopreserved sperm with those produced from fresh sperm. Cryopreserved sperm used for fry production was preserved with three extenders, Alsever’s solution, urea egg-yolk, egg-yolk citrate solution and one cryoprotectant, DMSO. Cryodiluents were prepared by mixing the cryoprotectants at 10% concentration of the extender (% v/v). Fry produced with fresh sperm was considered as control. For comparing the growth, 60 fry of 15 day-old for each treatment of both cryopreserved and control groups were stocked to glass aquarium (50 cm x 30 cm x 28 cm) and reared them for ten weeks. Growth of fry in terms of length and weight increment in both cryopreserved and control groups were measured weekly. The growth pattern was more or less similar for all the treatments and there was no significant difference (P>0.05) between them. The survival rate of fry produced from cryopreserved sperm was 82.3% and that from fresh sperm 88%, and there was no significant difference (P>0.05) between two groups. It is therefore, concluded that the use of cryopreserved sperm does not impair survival and growth of fry

Fundamental properties of brickwork with particular emphasis to brickwork arches

SIGLEAvailable from British Library Lending Division - LD:D56772/85 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Depth distribution and ecological preferences of periphytic algae in Kenyir Lake, the largest tropical reservoir of Malaysia

We studied the depth distribution of periphyton, growing on inundated dead trees in Kenyir Lake, Malaysia in June 1995. The algal floral composition and structure manifested changes down the depth gradient in terms of species richness, abundance, diversity and cell density. In regression analysis, all these algal attributes were negatively correlated with the depth gradients at P < 0.05. In terms of species richness, the bacillariophytes showed dominance over the cyanophytes and chlorophytes; whereas with respect to standing crop, the cyanophytes showed dominance over the bacillariophytes and chlorophytes. The chlorophyll a was higher at the mid and bottom-depths than the surface-depth in both the downstream and upstream sites, which showed that vertical productivity or biomass accumulation was greater in low light irradiance. The product-moment correlation analysis showed that conductivity, turbidity, dissolved oxygen, reactive phosphate and ammonium-nitrogen were highly correlated with the algal assemblage data. However, photosynthetic active radiation (PAR) showed poor correlation with the community data. These observations have cast some light on the autoecological characteristics, habitat preferences and environmental responses of tropical periphytic communities

Gas permeability of partially hydrated geosynthetic clay liner under two stress conditions

The results of a series of gas permeability tests, with monitoring of gravimetric/volumetric moisture content and total suction, on a commercially available needle-punched geosynthetic clay liner (GCL) are presented. GCL specimens were partially hydrated with deionised water under 2 and 20&thinsp;kPa confinement prior to testing. The tests were conducted at differential pressures ranging from 1 to 10&thinsp;kPa. Gas permeability was found to decrease with an increase in gravimetric/volumetric moisture content and a decrease of suction. The effect of the preconditioning stress was found to be more pronounced at gravimetric moisture contents greater than 40% (25% apparent degree of saturation, 0&middot;30&thinsp;m3/m3 volumetric moisture content), and suctions less than 1&middot;6&thinsp;MPa

CNS Depressant Effect of the Crude Ethanolic Extract of the Flowering Tops of Rosa Damascena

The ethanolic extract of the flowering tops of Rosa Damascena   (Rosaceae) was assessed for effect on the central nervous system (CNS) using a number of neuropharmacological experimental models in mice. The extract produced a dose-dependent reduction of the onset and duration of pentobarbitone-induced hypnosis, reduction of locomotor and exploratory activities in the open field, hole cross tests. At the same dose levels, the extract dose-dependently inhibited acetic acid-induced writhing in mice. These results suggest that the extract possess CNS depressant activity