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41.
The experiment was carried out to investigate the inclusion of underutilised legumes, Entada scandens, Canavalia gladiata and Canavalia ensiformis, seed meal in soybean-based diet in broilers. The utilisation of these wild legumes is limited by the presence of antinutrient compounds. Processing methods like soaking followed by autoclaving in sodium bicarbonate solution in E. scandens and C. gladiata and soaking followed by autoclaving in ash solution in C. ensiformis were adopted. The proximate composition of raw and processed samples of E. scandens, C. gladiata and C. ensiformis were determined. The protein content was enhanced in processed sample of E. scandens (46 %) and C. ensiformis (16 %). This processing method had reduced the maximum number of antinutrients such as tannins (10–100 %), trypsin inhibitor activity (99 %), chymotrypsin inhibitor activity (72–100 %), canavanine (60–62 %), amylase inhibitor activity (73–100 %), saponins (78–92 %), phytic acid (19–40 %) and lectins. Hence, the raw samples at 15 % and processed samples at 15 and 30 % were replaced with soybean protein in commercial broiler diet respectively. Birds fed with 30 % processed samples of E. scandens, C. gladiata and C. ensiformis showed significantly similar results of growth performance, carcass characteristics, organ weight, haematological parameters and serum biochemical parameters (cholesterol, protein, bilirubin, albumin, globulin and liver and kidney function parameters) without any adverse effects after 42 days of supplementation. The proper utilisation of these underutilised legumes may act as an alternative protein ingredient in poultry diets.  相似文献   
42.
Salt tolerance in soybean [Glycine max (L.) Merr.] is controlled by major quantitative trait loci (QTL) or single gene(s). Among soybean germplasm, wild soybean plant introduction PI 483463 was reported to have a single dominant gene for salt tolerance. The objective of this study was to genetically map the QTL in a recombinant inbred line (RIL) population derived from a cross between PI 483463 and Hutcheson. Simple sequence repeat (SSR) markers and universal soybean single nucleotide polymorphism (SNP) panel (the USLP 1.0) were utilized for molecular genotyping. The RILs were phenotyped in two independent tests in a greenhouse using a 1–5 scale visual rating method. The results showed that the salt tolerant QTL in PI 483463 was mapped to chromosome 3 in a genomic region between the Satt255 and BARC-038333-10036 markers. The favorable allele inherited from PI 483463 conferred tolerance to salinity and had an additive effect on reducing leaf scorch. A subset of 66 iso-lines was developed from the F3 families of the same cross and was used for genetic confirmation of the QTL. The integration of recombination events and the salt reaction data indicate that the QTL is located in the region of approximately a 658 kb segment between SSR03_1335 at nucleotide 40,505,992 and SSR03_1359 at nucleotide 41,164,735 on chromosome 3. This narrow region can facilitate further genomic research for salt tolerance in soybean including cloning salt tolerance genes.  相似文献   
43.
Sorghum accessions from Uganda were evaluated for grain mold and anthracnose resistance during the 2005 and 2006 growing seasons at the Texas A&M University Research Farm, near College Station, TX. Accession PI534117 and SC719-11E exhibited the lowest grain mold severities of 2.4, whereas, accessions PI534117, PI534144, PI576337, PI297199, PI533833, and PI297210, with SC748-5 were highly resistant to anthracnose in both years. Accessions PI534117, PI297134, PI297156 exhibited low grain mold severities in 2006. Significant negative correlation was recorded between grain mold and percent germination and high temperature in both years. In 2006, daily precipitation recorded significant positive correlation with grain mold. The seed mycoflora was analyzed across sorghum lines and treatments. In 2005, Curvularia lunata and Fusarium thapsinum were the most frequently recovered fungal species with 31 and 21% incidence, respectively, followed by Alternaria spp. (19%) and F. semitectum (13%). In 2006, predominant colonizers were F. thapsinum (58%), followed by Alternaria and F. semitectum with 15 and 10, percent respectively, while C. lunata had a 6% incidence. In this study, PI534117 holds promise for multiple disease resistance, as it had the lowest disease severity of grain mold and was highly resistant to anthracnose in both years. It also has a high germination rate, a high seed weight, and its short stature is more advantageous for the new A-line conversion program.  相似文献   
44.
In aquaculture industries, there is an urgent need to develop microbial control strategies, to control disease outbreaks. In recent years, probiotics are considered as a valid alternative for the use of antibiotics in aquaculture to prevent high mortality and promote growth. In the present study, seven strains of bacteria such as Bacillus licheniformis (DAB1), Bacillus pumilus (DAB2), Bacillus sp. (DAB3), Pseudomonas aeruginosa (DAP1), Pseudomonas sp. (DAP2), Pseudomonas aeruginosa (DAP3), Pseudomonas aeruginosa (DAP4), and three pathogenic Vibrio parahaemolyticus (DAV1, DAV2, DAV3) were isolated from healthy and diseased Fenneropenaeus indicus collected from the east coast of Tamilnadu, India. The strains were identified by biochemical analysis and 16S rRNA sequence methods. Among the seven probiotic strains tested, the cell-free extract from DAB1 and DAP1 exhibited higher inhibitory activity of V. parahaemolyticus than other isolates under in vitro conditions. The LC50 of DAV1, DAV2, and DAV3 was found to be ~103 CFU mL?1. Pathogenicity of three V. parahaemolyticus DAV1, DAV2, and DAV3 showed significant mortalities (40 %) in Artemia nauplii at inoculation densities of 103 CFU mL?1 when compared to the controls (unchallenged nauplii). A significant reduction in mortality (P < 0.001) was found by addition of 106 CFU mL?1 of DAB1 and DAP1 strains in nauplii against the pathogens. In conclusion, the present study result reveals that DAB1 and DAP1 have potential applications for controlling pathogenic V. parahaemolyticus in Artemia culture systems and aquaculture practices.  相似文献   
45.
The X-ray in the field of medical imaging is an important diagnostic tool, but it has been identified that there are potential radiation risks associated with the X-ray radiation scans. These risks have traditionally been guarded against using lead based shields. Lead has excellent radiation shielding properties, but it is also heavy and a potential health and environmental hazard due to its toxicity. Thus, there have been studies seeking to find an alternative that is as effective and yet counters the other drawbacks. In this paper, preliminary studies were conducted to assess the shielding effect of barium sulphate (BaSO4) and bismuth oxide (Bi2O3) on the coated fabric samples. X-ray transmission resulting from standard lead coated samples, uncoated fabric, BaSO4, and BaSO4/Bi2O3 coated fabrics was evaluated via measuring the penetration of primary radiation. Different properties such as mass per unit area, material thickness, and surface morphology were examined. All samples were irradiated by X-ray at 80 kVp to measure the amount of transmissions. The X-ray transmission level associated with BaSO4 ranged from 84.5 % to 70.5 %. However, this level was elevated to 55.6 % when BaSO4/Bi2O3 mixture was applied on the fabric. The theoretical attenuation coefficient values associated with different coating mixtures comprising different weight proportions of BaSO4, Bi2O3, and PVC were determined between 0 MeV and 105 MeV using XCOM code. The XCOM results implied that the X-ray attenuation coefficient among all prepared coatings should be the mixture comprising 13.3 wt% Bi2O3/20 wt% BaSO4/66.7 wt% PVC, which was in agreement with the experimental results obtained from X-ray transmission measurements.  相似文献   
46.
Soil contaminated by chromium (Cr) is a major concern for sustainable agriculture. Considering this as a basis, the present study was designed to isolate Cr(VI)-reducing and plant growth-promoting bacterial strain from contaminated sampling sources. In this study, Rhizobium strain ND2 was isolated from the root nodules of Phaseolus vulgaris grown in leather industrial effluent contaminated soil. The strain ND2 exhibited strong resistance to different heavy metals and reduced 30 and 50 µg ml?1 concentrations of Cr(VI) completely after 80 and 120 h of incubation, respectively, as well as chromium adsorption and immobilization were confirmed by scanning electron microscopic equipped with energy X-ray spectroscopy. In addition, the strain produced 21.73 and 36.86 µg ml?1 of indole-3-acetic acid at 50 and 100 µg ml?1 of L-tryptophan supplimentations, respectively. Strain ND2 positively affected the exo-polysaccharide, ammonia, protease and catalase production and stimulated root length of various test crops under Cr(VI) stress. Moreover, Rhizobium strain ND2 has the potential to colonize the diverse agricultural crops. Thus, the present findings strongly suggested that the multipotential properties of ND2 could be exploited for bioremediation of contaminated sites with Cr(VI) as well as potential bio fertilizer for enhancing the agricultural productivity.  相似文献   
47.
48.
The objective of this study was to investigate the reason for variation in the virulence of white spot syndrome virus (WSSV) from different shrimp farms in the Southeast coast of India. Six isolates of WSSV from farms experiencing outbreaks (virulent WSSV; vWSSV) and three isolates of WSSV from farms that had infected shrimps but no outbreaks (non‐virulent WSSV; nvWSSV) were collected from different farms in the Southeast coast of India. The sampled animals were all positive for WSSV by first‐step PCR. The viral isolates were compared using histopathology, electron microscopy, SDS‐PAGE analysis of viral structural proteins, an in vivo infectivity experiment and sequence comparison of major structural protein VP28; there were no differences between isolates in these analyses. A significant observation was that the haemolymph protein profile of nvWSSV‐infected shrimps showed three extra polypeptide bands at 41, 33 and 24 kDa that were not found in the haemolymph protein profile of vWSSV‐infected shrimps. The data obtained in this study suggest that the observed difference in the virulence of WSSV may not be due to any change in the virus, rather it could be due to the shrimp defence system producing certain factors that help it to accommodate the virus without causing any mortality.  相似文献   
49.
Recurring mortalities inflicted by the cirolanid isopod Cirolana fluviatilis in the juveniles of the Asian seabass, Lates calcarifer , stocked in a cage farm in the Cochin backwaters, from November 2006 to May 2007, were investigated. Hatchery-reared fingerlings (size 8–12 cm) were cultured in floating cages and mortalities were observed after a rearing period of 1 month. The fish were found dead in the cages, with only the remnants of fish skeleton and all the flesh eaten away. Investigations revealed a very high abundance of isopods, identified as C. fluviatilis (Crustacea, Malacostraca, Isopoda and Ciroloanidae). During the first 2 months of stocking, 35% of the fingerlings died, and the cumulative mortality reached 45% in 6 months, considerably reducing the profits from the venture. Management measures for the control of the isopods are discussed. This is the first report on the isopod, C. fluviatilis , inflicting serious mortalities in a tropical cage-rearing system in the southwest coast of India.  相似文献   
50.
Mulberry is an economic tree being cultivated in China, India and several other Asian countries to feed the silkworm, Bombyx mori, as mulberry leaf is the only food material available for this insect. The recent burst in the industrialization and urbanization has considerably reduced the availability of land for agriculture purposes in these Asian countries. This, in turn, has added much pressure on many agro-based industries, including sericulture, to utilize the hitherto unutilized or marginally utilized areas for crop production. Sericulture, a rural agro-based industry, is attempting to expand mulberry cultivation to drought- and salinity-affected lands. Mulberry is only moderately tolerant to salinity and drought stresses, thus utilization of natural variations in stress tolerance does not hold much promise. Therefore, efforts are being taken to develop stress-tolerant varieties using modern biotechnological methods, including transgenesis. This paper provides an overview of the progress made to achieve this latter goal, highlighting the problems and prospects. Different methodologies used to achieve transgenic mulberry, their merits and demerits are also discussed.  相似文献   
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