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The aim of the present study was to examine whether cumulus and fibroblast cell nuclear-transferred oocytes, which have high and low potential to develop into normal calves, respectively, are different in terms of in their patterns of timing of first cleavage and in their relationships between timing of first cleavage and in vitro developmental potential. The timing of first cleavage was similar in both types of nuclear-transferred and in vitro fertilized oocytes. More than 86% of the oocytes cleaved within 24 h after activation or in vitro fertilization; these oocytes contributed to more than 98% of the total number of blastocysts in all three groups. The potential of oocytes that cleaved at different intervals to develop into blastocysts differed among the groups. The developmental potential of the cumulus cell nuclear-transferred oocytes and in vitro fertilized oocytes decreased with the increase in time required for cleavage. Fibroblast cell nuclear-transferred oocytes that cleaved at 20 h, an intermediate cleaving time, had higher potential to develop into blastocysts. The results of the present study suggest that the type of donor nucleus used for nuclear transfer affects the timing of first cleavage. 相似文献
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Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献
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Ether and methanol extracts of Ixora coccinea dry leaves were tested for their antimicrobial activity. Ether fraction was found to be more active than the methanol fraction. 相似文献
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ZS Perényi O Szenci PV Drion H Banga-Mboko NM Sousa B El Amiri JF Beckers 《Reproduction in domestic animals》2002,37(6):324-329
Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids. 相似文献
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Reduction in the mRNA expression of sVEGFR1 and sVEGFR2 is associated with the selection of dominant follicle in cows 下载免费PDF全文
PV Ortega Serrano A Guzmán CG Hernández–Coronado H Castillo‐Juárez AM Rosales‐Torres 《Reproduction in domestic animals》2016,51(6):985-991
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development. 相似文献
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In vitro Development of Buffalo Oocytes in Media-containing Fluids from Different Size Class Follicles 总被引:1,自引:0,他引:1
S Nandi HM Raghu BM Ravindranatha PSP Gupta PV Sarma 《Reproduction in domestic animals》2004,39(1):33-38
Studies were conducted to investigate the effect of supplementation of fluid from different sized class [small (SFF, < 3 mm), medium (MFF, 3-8 mm) and large (LFF, > 8 mm)] of normal and cystic (CFF) ovarian follicles in oocyte culture media on oocyte maturation rate and embryo development in vitro and to test the efficacy of follicular fluid (FF) from different size classes as a whole oocyte maturation medium. Results suggested that FF were capable of developing buffalo oocytes to embryonic stage in vitro although its efficacy was lower than that of serum. Regardless of high maturation rates after in vitro maturation (IVM) in media containing FF or IVM in whole FF, low blastocyst rates were obtained after in vitro fertilization (IVF) and culture of embryos. Follicular fluid from small follicles had significantly (p < 0.05) higher potential of developing buffalo oocytes to embryonic stage in vitro than that from medium and large follicles. Cystic FF was not capable of supporting development of buffalo oocytes in vitro. 相似文献
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JM Morrell B Persson H Tjellström A Laessker H Nilsson M Danilova PV Holmes 《Reproduction in domestic animals》2005,40(6):522-525
In the absence of commercially viable methods for cryopreserving turkey spermatozoa, new processing methods are required to extend the functional life of stored turkey spermatozoa for artificial insemination. The present study evaluates the efficacy of a new extender (Turkey Semen Extend) and investigates the use of density gradient centrifugation in processing turkey spermatozoa for artificial insemination. The new extender is compared with two commercially available turkey semen extenders, Beltsville Poultry Semen Extender and Ovodyl. Turkey spermatozoa in Turkey Semen Extend were still motile 20 h after collection, representing a considerable improvement over the other semen extenders (40%, 0% and 8% for Turkey Semen Extend, Beltsville Poultry Semen Extender and Ovodyl, respectively). A field trial on a commercial turkey farm showed improved fertilization rates following insemination of turkey hens with semen extended in Turkey Semen Extend (89.7%) compared with Beltsville Poultry Semen Extender (86.9%). This difference is statistically significant (p < 0.05). Processing on a density gradient, optimized for turkey spermatozoa, also increased sperm survival (50% gradient-prepared spermatozoa still motile after 18 h compared with <10% non-processed spermatozoa). Preliminary studies indicate that gradient preparation of spermatozoa may aid survival during cryopreservation. 相似文献
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Gograj Singh Jat Anilabh Das Munshi Tusar Kanti Behera Harshwardhan Choudhary Prasanta Dash Amarnath Ravindran 《The Journal of Horticultural Science and Biotechnology》2019,94(1):24-32
Gynoecious is an important economic trait of cucumber for determinant of earliness and yield, yet genetic mechanism is not well understood for this trait. The experiment was conducted using F2 mapping population by crossing of PPC-2, a gynoecious and parthenocarpic line with Pusa Uday (monoecious and non-parthenocarpic cultivar). Out of 179 SSR markers screened, 39 markers differentiated the gynoecious and monoecious parents. However, only 17 markers were segregating with F2 mapping population, those were used for genotyping and linkage map analysis and these markers were placed along with F locus on chromosome 6 covering a total distance of 100.4cM. The SSR markers, SSR13251 and UW020605 were found to be closely linked to gynoecious (F) locus at 1.0 and 4.5 cM, respectively. The segregation of F2 population of PPC-2 × Pusa Uday and GPC-1 × Punjab Naveen and test crosses for sex type herein suggested that single dominant gene controlled the gynoecious sex expression in cucumber particularly in gynoecious genotypes PPC-2 and GPC-1. Therefore, the monogenic dominant nature of gynoecious sex identified in the present experiment and SSR markers closely linked to the F locus will be useful in marker-assisted backcross breeding for transfering gynoecious trait into horticulturally desirable varieties. 相似文献