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31.
Comparison of efficiency of in vitro cloned sheep embryo production by conventional somatic cell nuclear transfer and handmade cloning technique 
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下载免费PDF全文 S Khan M Tali A Khan S Bhat A Ashraf MH Bhat F Khan RA Shah 《Reproduction in domestic animals》2018,53(2):512-518
Conventional somatic cell nuclear transfer (SCNT) technique of in vitro production of cloned embryos involves use of costly and complicated micromanipulators. Handmade cloning (HMC) technique has been applied as efficient and cost‐effective alternative in many livestock species. The aim of the present study was to compare the efficiency of in vitro production and in vitro development of cloned sheep embryos by the two techniques. Cloned embryos were produced by conventional SCNT using micromanipulator apparatus and by HMC technique. Enucleation efficiency and efficiency of fusion with somatic cell (nucleus donor) were compared. Cleavage percentage was observed on day 2 of in vitro culture (IVC), and morula and blastocyst percentages were calculated on day 7 of IVC. Higher enucleation efficiency (96.98 ± 1.01 vs. 93.62 ± 1.03; p > .05) as well as fusion efficiency was obtained with HMC technique than with conventional SCNT (96.26 ± 1.34 vs. 92.63 ± 0.70, p < .05); 181 cloned sheep embryos were produced in vitro by conventional SCNT and 92 by HMC. Cleavage percentage observed on day 2 of in vitro culture was higher in HMC than SCNT (66.92 ± 3.72 vs. 55.97 ± 2.5, respectively, p < .05). Morula percentage obtained was higher in SCNT than HMC (44.12 ± 2.93 vs. 30.43 ± 6.79, respectively, p < .05), whereas blastocyst percentage obtained by HMC was higher (12.46 ± 4.96) than SCNT (5.31 ± 2.25; p > .05). It was inferred that HMC technique provides a cost‐effective and efficient method of in vitro production of cloned sheep embryos with a comparatively simpler technique with a possibility of automation. Efficiency of cloned embryo production could be improved further by propagating and standardizing this technique. 相似文献
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A trial of Avicennia officinalis L. with five different spacings was conducted in the newly accreted lands along the western coastline(Patuakhali district) of Bangladesh since 1993 to assess growth performance and the effect of spacing on tree growth. Data on tree density, height, diameter, bole height, crown diameter were recorded and analyzed when the stand was 19 years old. Mean height ranged from 12.89-13.52 m and diameter at breast height(dbh) from 26.57-32.16 cm in plots of different spacings. The mean annual height increment ranged from 0.67-0.71 m, mean annual diameter increment from 1.40-1.69 cm and wood volume from 6.02-10.04 m3·ha-1·a-1 in different treatments. Significantly greater diameter(32.16 cm) and wood volume(10.04 m3?ha-1?a-1) were obtained with wider(2.13 m × 2.13 m) spacing than with closer spacings. But tree growth was unaffected by other spacings. Growth data were also recorded from other A. officinalis plantations raised by Forest Department(FD) on different islands in Patuakhali and Bhola districts of Bangladesh. At these sites, mean annual height increment ranged from 0.33-0.62 m, mean annual diameter increment from 0.72-1.37 cm and wood volume from 1.55-5.73 m3?ha-1?a-1. The growth performance of A. officinalis indicated that the newly accreted lands along the western shoreline may be suitable for raising Avicennia plantations for the enrichment of coastal vegetation. 相似文献
33.
Deforestation occurs at an alarming rate in upland watersheds of Bangladesh and has many detrimental effects on the environment. This study reports the effects of deforestation on soil biological properties along with some important physicochemical parameters of a southern upland watershed in Bangladesh. Soils were sampled at 4 paired sites, each pair representing a deforested site and a forested site, and having similar topographical characteristics. Significantly fewer(p≤0.001) fungi and bacteria, and lower microbial respiration, active microbial biomass, metabolic and microbial quotients were found in soils of the deforested sites. Soil physical properties such as moisture content, water holding capacity, and chemical properties such as organic matter, total N, available P and EC were also lower in deforested soils. Bulk density and pH were significantly higher in deforested soils. Available Ca and Mg were inconsistent between the two land uses at all the paired sites. Reduced abundance and biomass of soil mesofauna were recorded in deforested soils. However, soil anecic species were more abundant in deforested soils than epigeic and endogeic species, which were more abundant in forested soils than on deforested sites. 相似文献
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F Shaluei MR Imanpoor A Shabani MH Nasr‐Esfahani 《Reproduction in domestic animals》2014,49(2):210-218
A series of five experiments were conducted to explore suitable conditions for storing of goldfish embryos in a chilled state. The factors studied were embryo stage, storage temperature, physiological saline solutions and goldfish artificial coelomic fluid (GFACF) medium, antibiotics (penicillin and streptomycin), antioxidants (vitamin E, vitamin C), buffer (Hepes, Tris) and BSA (bovine serum albumin). First, goldfish embryos at eight developmental stages were incubated in aerated and dechlorinated tap water at 0°C for 24 h. Result shows that early developmental stages were most sensitive to chilling. Heartbeat‐stage goldfish embryos were chilled at 0, 4 or 8°C for up to 72 h in water, and chilled storage was possible only for up to 18, 24 and 48 h at 0, 4 and 8°C, respectively, without a decrease in viability. Chilling of goldfish embryos at 8°C in GFACF medium and Dettlaff's solution instead of water and other physiological saline solutions prolonged their viability (p < 0.01). Nevertheless, viability of chilled embryos in GFACF medium was slightly, but non‐significantly, higher than in Dettlaff's solution. Supplementation of the GFACF medium with antibiotics, Hepes or BSA increased the viability of chilled embryos, but the tested vitamin E analogue Trolox, vitamin C or Tris concentration had no effect on embryo viability. The outcome of this series of experiments shows that heartbeat‐stage goldfish embryos could be chilled for 60 h in GFACF supplemented with 25 mm Hepes, 100 U/ml penicillin, 10 μg/l streptomycin and 1 g/l BSA in such a way that embryonic development does not proceed, and viability is not lost. 相似文献
36.
Arsenic Accumulation in Rice (Oryza sativa L.) Varieties of Bangladesh: A Glass House Study 总被引：1，自引：0，他引：1
M. Azizur Rahman H. Hasegawa M. Mahfuzur Rahman M. Nazrul Islam M. A. M. Miah A. Tasmin 《Water, air, and soil pollution》2007,185(1-4):53-61
A glass house study was conducted to investigate the accumulation of arsenic in tissues of five widely cultivated rice (Oryza sativa L.) varieties of Bangladesh namely BRRI dhan 28, BRRI dhan 29, BRRI dhan 35, BRRI dhan 36, BRRI hybrid dhan 1. Arsenic concentrations were measured in straw, husk and brown and polish rice grain to see the differential accumulation of arsenic among the rice varieties. The results showed that the concentrations of arsenic in different parts of all rice varieties increased significantly (p?<?0.05) with the increase of its concentrations in soil. The rice varieties did not showed significant differences in arsenic accumulation in straw, husk, brown and polish grain when the concentrations of arsenic in soil was low. However, at higher concentrations of arsenic in soil, different rice varieties showed significant differences in the accumulations of arsenic in straw, husk and grain. Significantly higher concentrations of arsenic in straw and husk of rice were observed in BRRI hybrid dhan 1 compared to those of other verities. The BRRI dhan 28 and 35 concentrated significantly higher amount of arsenic in brown and polish rice grain compared to those of other rice varieties. The results imply that arsenic translocation from root to shoot (straw) and husk was higher in hybrid variety compared to those of non-hybrid varieties. Arsenic concentrations in brown and polish rice grain of five rice varieties were found to follow the trend: BRRI dhan 28 > BRRI dhan 35 > BRRI dhan 36 > BRRI dhan 29 > BRRI hybrid dhan 1. The order of arsenic contents in tissues of rice was: straw > husk > brown rice grain > polish rice grain. 相似文献
37.
Summary A haploid breeding program was initiated to develop doubled haploid salt tolerant rice breeding line via anther culture. Two sensitive breeding lines BR4608-R1-R2 and BR4909-R1-R2 were crossed with a salt tolerant line IR13146-13-3-3 to transfer its salt tolerant character to the doubled haploids.Anther from confirmed F1s of the two crosses were cultured in defined medium for callus induction and eventual plant regeneration. Fifteen doubled haploid (DH) lines were obtained from two crosses. Test for salt tolerance were done in vitro. Five out of 15 lines were found tolerant at the level of 8–10 decisiemens/m (ds/m) while the rests were sensitive to that level of salinity.Field experiment was conducted to evaluate the doubled haploids under saline and non saline soil. Five salt tolerant lines produced comparable yield with the resistant control (BR 23) under saline condition, whereas these lines yielded even higher in non saline soil under irrigated condition when evaluated with other 10 sensitive DH linesAbbreviations LSD
Least Significant Difference
- NAA
Napthalene Acetic Acid 相似文献
38.
This study reports the effects of shifting cultivation at slashing stage on soil physicochemical properties at Bandarban Sadar Upazila in Chittagong Hill Tracts of Bangladesh. At this initial stage of ... 相似文献
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Contribution of forests to the livelihood of the Chakma community in the Chittagong Hill Tracts of Bangladesh 总被引：1，自引：0，他引：1
Md. Danesh Miah Sheeladitya Chakma Masao Koike Nur Muhammed 《Journal of Forest Research》2012,17(6):449-457
Natural forests offer numerous benefits to indigenous communities and society at large. Incomes from forest sources play an important role in rural households. In addition to this, environmental sources in the forests contribute significantly to rural households’ livelihoods and economic well-being. This paper examines the contributions of forests to the livelihoods of the Chakma tribe in Bangladesh. Using the data from 60 randomly sampled households from three villages, it measured forest-resource use with a monetary yardstick. As revealed through analyses, natural forest-sourced income occupies the second-largest share in total average household income next to shifting cultivation income in the study area. Forest products represent an important component in the local livelihoods, with a direct forest income of 11,256?tk?year?1?household?1 (tk = taka, the national currency of Bangladesh; US$1?=?tk70), or 11% of the total income, in addition to the households receiving monetary benefits of 18,951?tk?year?1?household?1, or 21% of the total income, through the consumption of forest products. The remaining income came from shifting cultivation practice. It was also observed that larger families with more people gathering forest products realized more forest income. This study will be relevant to forest and environmental policy-makers as well as indigenous community development practitioners. 相似文献
40.
H. S. Bariana U. K. Bansal A. Schmidt A. Lehmensiek J. Kaur H. Miah N. Howes C. L. McIntyre 《Euphytica》2010,175(2):251-260
The Puccinia striiformis f. sp. tritici (Pst) pathotype, 134 E16A+, detected in 2002 in Australia, produced relatively lower and higher adult plant stripe rust responses,
respectively, on cultivars Kukri and Janz in comparison to the pre-2002 Pst pathotype 110 E143A+. Molecular mapping of adult
plant stripe rust response variation among 180 Kukri/Janz-derived doubled haploid lines over 4 years, two each with Pst pathotypes
110 E143A+ and 134 E16A+, was performed. QYr.sun-7B and QYr.sun-7D were consistently contributed by Kukri and Janz, respectively. QYr.sun-7D corresponded to the genomic location of Yr18 and QYr.sun-7B remains to be formally named. QYr.sun-1B, QYr.sun-5B, and QYr.sun-6B were detected during more than one season irrespective of the Pst pathotypes used, whereas QYr.sun-3B was identified only during the 2003 crop season. QYr.sun-1A contributed by Janz, and QYr.sun-2A from Kukri, were detected only against Pst pathotypes 110 E143A+ and 134 E16A+, respectively. The DH lines showing better
resistance than the either parent carried combinations of 4 to 6 QTL. These lines are currently being used as stripe rust
resistance donors in wheat breeding programs. 相似文献