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41.
SG Chethan SK Singh J Nongsiej HB Rakesh RP Singh N Kumar SK Agarwal 《Reproduction in domestic animals》2014,49(3):403-408
Interferon‐τ (IFN‐τ) has been recognized as the primary embryonic signal responsible for maternal recognition of pregnancy. Uterine endometrium produces both prostaglandin F2α (PGF2α) and prostaglandin E2 (PGE2). PGF2α is responsible for the luteolysis; however, PGE2 favours establishment of pregnancy by its luteoprotective action. In this study, the dose‐response effect of recombinant bovine IFN‐τ (rbIFN‐τ) on prostaglandin (PG) production by buffalo endometrial stromal cells cultured in vitro was studied. Buffalo endometrial stromal cells were isolated by double enzymatic digestion, initially with trypsin III followed by a cocktail of trypsin III, collagenase type II and DNase I and subsequently cultured till confluence. Further, cells were treated with different doses of rbIFN‐τ (0.001, 0.01, 0.1, 1.0 and 10 μg/ml) and keeping a separate set of control. Culture supernatant was collected after 6, 12 and 24 h of treatment. PG levels in the culture supernatant were measured by enzyme immune assay (EIA) and total cellular protein estimated by Bradford method. Results indicated that buffalo endometrial stromal cells following rbIFN‐τ treatment enhanced the secretion of both PGE2 and PGF2α, and also its ratio in a strict dose‐dependent manner with a significant increase (p < 0.01) in PGE2 production at 1 μg/ml dose of rbIFN‐τ and maximal stimulation for both PG was observed at 10 μg/ml. Further, both PG production and its ratio were increased significantly (p < 0.01) in a time‐dependent fashion in all the groups at 6, 12 and 24 h post‐treatment with highest level achieved at 24 h as compared with control. Absolute levels of PGE2 remained higher than PGF2α indicating PGE2 as the major PG produced by endometrial stromal cells. The dose‐dependent response of rbIFN‐τ signifies the importance of optimum concentration of IFN‐τ for the embryonic development especially during the critical period to establish successful pregnancy. 相似文献
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A George RA Shah R Sharma P Palta SK Singla RS Manik MS Chauhan 《Reproduction in domestic animals》2011,46(3):444-447
Parthenogenetic activation using zona‐free oocytes offers an alternative model that could be applied to develop protocols for the activation of reconstructed embryos for cloning. The aim of this study was to compare the efficacy of different methods for the activation of zona‐free buffalo oocytes in terms of their effects on the developmental competence of parthenogenetic embryos. The effects of zona removal on parthenogenetic activation and in vitro developmental competence of metaphase II oocytes were also examined. All activation methods were followed by incubation of 2 mm 6‐dimethylaminopurine (6‐DMAP) for 4 h. Out of three different pulse strengths (1.2, 2.1 or 3.3 kV/cm) used, 2.1 kV/cm resulted in the highest blastocyst rate (25.3%). On comparing different chemical agents and electric pulse, highest blastocyst rate was observed for calcium ionophore (CaI) (28.6%) followed by ethanol (25.0%), electric pulse (22.5%) and combined CaI and ethanol treatment (16.7%) although differences among them were not significant. Furthermore, a significantly reduced developmental potential was observed in zona‐free oocytes when compared to zona‐intact ones up to the blastocyst stage (44.3% vs 27.1%). In conclusion, zona‐free buffalo oocytes can be successfully activated for parthenogenetic development using chemical or electrical stimulation. Out of different agents examined, CaI followed by 6‐DMAP resulted in the highest blastocyst rate. 相似文献
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选用地理纬度相似的中国辽宁省、美国俄亥俄州新近育成的大豆品种,分别和中国辽宁省20世纪20年代老品种进行了农艺性状的比较研究。结果表明:中美大豆品种主要农艺性状遗传改进的共有趋势是主茎荚数、单株荚数、3粒和4粒荚率、单株粒数、单株粒重、百粒重、粒茎比、收获指数明显增加。株高、主茎节数、节间长度和分枝数显著降低。美国新品种的单株荚数、单株粒数和粒茎比的增加幅度明显高于同期的中国新品种。而中国新品种的百粒重显著高于美国新品种。施肥水平对不同年代大豆品种主要农艺性状也有一定影响,且美国新品种在高肥条件下比中国新品种表现出更高的增产潜力。 相似文献
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Golla K Selokar NL Saini M Chauhan MS Manik RS Palta P Singla SK 《Reproduction in domestic animals》2012,47(5):842-848
Somatic cells in milk are a potential source of nuclei for nuclear transfer to produce genetically identical animals; this is especially important in animals that are susceptible to risks of bacterial infection on biopsy collection. In this study, a minimum of 10 milk samples were collected from each of the three buffaloes representing Murrah breed. All the samples were processed immediately and cell colonies were obtained. Cell colonies from one buffalo (MU-442) survived beyond 10 passages and were evaluated by fluorescence microscopy and used in nuclear transfer experiments. In culture, these cells expressed vimentin, indicating they were of fibroblast origin similar to ear cells. We compared the effectiveness of cloning using those milk-derived fibroblast (MDF) cells and fibroblast cells derived from the ear derived fibroblast (EDF). Fusion and cleavage rates of MDF-NT and EDF-NT embryos were found to be similar (92.43 ± 1.28% vs 94.98 ± 1.24%, and 80.27 ± 1.75% vs 84.56 ± 3.73%, respectively; p > 0.01); however, development to blastocyst stage and total cell number was higher for EDF-NT embryos (50.24 ± 2.54%, 227.14 ± 13.04, respectively, p < 0.01), than for MDF-NT embryos (16.44 ± 0.75%, 170.57 ± 4.50 respectively). We conclude that somatic cells from milk can be cultured effectively and used as nucleus donor to produce cloned blastocyst-stage embryos. 相似文献
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Rameshbabu K Sharma R Singh KP George A Chauhan MS Singla SK Manik RS Palta P 《Reproduction in domestic animals》2012,47(2):e22-e25
This study examined the presence of immunoreactivity and mRNA for different nitric oxide synthase (NOS) isoforms in immature and in vitro matured oocytes and in embryos at two‐, four‐ and eight‐cell, and morula and blastocyst stages in buffalo. Oocytes obtained from slaughterhouse buffalo ovaries were subjected to in vitro maturation in TCM‐199 + 10% FBS + 5 μg/ml pFSH + 1 μg/ml estradiol‐17β + 0.81 mm sodium pyruvate + 10% buffalo follicular fluid + 50 μg/ml gentamycin sulphate for 24 h in a CO2 incubator (5% CO2 in air) at 38.5°C. Following in vitro fertilization carried out by incubating them with 2–4 million spermatozoa/ml for 18 h, the presumed zygotes were cultured in mCR2aa medium containing 0.6% BSA and 10% FBS for up to 8 days post insemination. Immunofluorescence staining of NOS using antibodies that cross‐reacted either with all the NOS isoforms i.e., universal (uNOS) or specifically with inducible (iNOS) or endothelial (eNOS) isoforms revealed that NOS was present in oocytes and embryos at all the stages examined. Examination of the semi‐quantitative expression of NOS genes by RT‐PCR revealed that the iNOS, eNOS and nNOS mRNA was present in the immature and mature oocytes and in all the embryonic stages examined. In conclusion, it was demonstrated in the present study that immunoreactivity and mRNA for different NOS isoforms was present in buffalo oocytes and pre‐implantation stage embryos. 相似文献
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Effect of testicular tissue lysate on developmental competence of porcine oocytes matured and fertilized in vitro 
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下载免费PDF全文 AK Singh S Naskar B Saikia Y Vashi S Gupta S Banik MK Tamuli V Pande DK Sarma SK Dhara 《Reproduction in domestic animals》2017,52(2):183-188
The objective of the present study was to investigate the effect of testicular tissue lysate (TTL) on developmental competence of germinal vesicle (GV) stage porcine oocytes. Two types of TTL were prepared through repeated freeze–thaw in liquid nitrogen, one from whole testicular tissue (wTTL) and other from either of four different sections of testes, namely just beneath the tunica albuginea (TA), from the transitional area between the seminiferous cord/tubules and the mediastinum testis (TR) and from the intermediate area (parenchymal tissue origin) and CE (cauda epididymis origin). The whole or section‐wise TTL treatments were given for 44 hr during in vitro maturation (IVM). Oocyte maturation was done in either of the two media, namely defined (high‐performance basic medium for porcine oocyte maturation, commercially available) and serum containing (TCM199). After maturation, oocytes were co‐incubated with fresh spermatozoa for 6 hr and then transferred to embryo culture media. Treatment of GV stage oocytes with wTTL (1 mg/ml) increased the cleavage and morula percentage rate (69.23 ± 6.23 and 48.15 ± 6.77, respectively) than that of their control (58.33 ± 8.08 and 32.54 ± 5.53, respectively) in defined media, and in serum‐containing media, cleavage and morula percentage rate were almost equal in both treatment (54.56 ± 7.79 and 34.70 ± 6.78, respectively) and control (59.52 ± 8.21 and 38.52 ± 6.54, respectively). However, effect of wTTL was not significant. In case of section‐wise TTL supplements, TR section significantly (p < .01) improved cleavage and morula rate (58.43 ± 7.98 and 36.14 ± 6.89, respectively) followed by TA. In conclusion, present study indicates that IVM, in vitro fertilization and in vitro culture of embryo are improved in the presence of TTL, particularly its TR section. Further study is expected to reveal the principal components of TTL which may prove useful for IVM. 相似文献
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SUMMARY The epidemiological and clinical features of big liver and spleen disease (BLS) in flocks on two broiler breeder farms were investigated by serology and gross pathology. The most common necropsy findings on farm 1 were splenomegaly and hepatomegaly, with kidney enlargement in some birds. In one flock (farm 1), a decline in egg production began at 40 weeks of age and lasted for 9 weeks. Seroconversion to BLS antigen was first detected at 45 weeks (3.1% of birds) and increased to 72% at 50 weeks, which coincided with clinical recovery in the flock. Antigen was detected before antibody at 44 weeks and persisted at low incidence (<15%). Farm egg production statistics and serology indicated that the disease affected all flocks on the farm. In three of eight flocks, seroconversion was detected in birds before peak production. The birds in the remaining sheds did not seroconvert or become sick until after peak production. On the second farm, sampling began within a flock already experiencing BLS. Clinical signs and pathology were similar to those seen in flocks on farm 1. However, the lesions that were seen in the pancreas in 15% of birds have not been reported previously. BLS antibody was detected in 78%, and circulating antigen in 14%, of sick birds. 相似文献
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Capacitation is a biological phenomenon occurring prior to fertilization and is a multiple event process. Many physiological and biochemical changes takes place during the process; these changes are related to lipid composition of membrane, intracellular modulation of ion concentration, protein phosphorylation, sperm movement and membrane permeability. These events occur when the sperm is exposed to the new environment of ion concentration in the female reproductive tract. Ions such as bicarbonate and calcium facilitate capacitation by activating adenylyl cyclase, thus initiating protein kinase A (PKA) signalling cascade. Extracellular‐regulated kinase pathway is activated by ligand binding to the membrane receptors and intracellular activation by reactive oxygen species (ROS). Activation of these pathways leads to the phosphorylation of different proteins, which is associated with events such as capacitation, hyperactivation and acrosome reaction that are essential for successful fertilization. Extensive studies were carried out on protein phosphorylation in relation to capacitation, but its role still remains ambiguous. 相似文献
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