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排序方式: 共有222条查询结果,搜索用时 15 毫秒
1.
Mohammadreza Ebrahimi Laura Mara Bernardo Chessa Fabrizio Chessa Abbas Parham Maria Dattena 《Reproduction in domestic animals》2021,56(3):467-475
Microinjection of exogenous DNA into the cytoplasm of matured oocytes or zygotes is a promising technique to generate transgenic animals. However, the data about the microinjection time and procedure in sheep are limited and have not treated in detail. To obtain more in-depth information, the Sarda sheep oocytes from abattoir-derived ovaries were subjected to IVM and IVF. Then, the GFP plasmid as a reporter gene was injected into the cytoplasm of MII oocytes (n: 95) and zygotes at different post-insemination intervals (6–8 hpi, n: 120; 8–10 hpi, n: 122; 10–12 hpi, n: 110 and 12–14 hpi, n: 96). There were no significant differences in the cleavage rates between the groups. However, blastocyst rate of injected zygotes at all-time intervals was significantly lower than injected MII oocytes and control group (p < 0.05). Interestingly, the proportion of GFP-positive embryos was higher at 8–10 hpi compared with other injected groups (4 % versus 0 %, p < 0.01). Among these, the proportion of mosaic embryos was high and two of those embryos developed to the blastocyst stage. In conclusion, we settled on the cytoplasmic microinjection of GFP plasmid at 8–10 hpi as an optimized time point for the production of transgenic sheep and subsequent experiments. 相似文献
2.
Sharifi H Nassiri SM Esmaelli H Khoshnegah J 《Journal of Feline Medicine and Surgery》2007,9(6):514-517
A 14-year-old female domestic shorthair cat was presented to Tehran University Veterinary Teaching Hospital for a persistent fever, anorexia, intermittent vomiting, weight loss and weakness. The main clinical signs were pale mucous membranes, dehydration and splenomegaly. The complete blood count and serum biochemistry tests revealed non-regenerative anaemia, thrombocytopenia and increased alkaline phosphatase (ALP) activity. An enzyme-linked immunosorbent assay (ELISA) test for feline leukaemia virus was negative. Blood film and bone marrow examination revealed a large number of immature eosinophils with variable sizes and numbers of faintly azurophilic granules. Cytochemical staining of blood film demonstrated 70% positive cells for ALP activity. Four percent CD34 positive cells were detected by flow cytometry. As eosinophilic leukaemia is difficult to identify by light microscopy, well-defined diagnostic criteria and the use of flow cytometry and cytochemical staining can improve the ability to correctly diagnose this type of leukaemia in cats. 相似文献
3.
Comparative effects of Shirazi thyme and vitamin E on some growth and plasma biochemical changes in common carp (Cyprinus carpio) during cadmium exposure
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Mohammad Mohiseni Maryam Sepidnameh Dara Bagheri Mahdi Banaee Behzad Nematdust Haghi 《Aquaculture Research》2017,48(9):4811-4821
Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet. 相似文献
4.
Soheila Espanani Mohammad Mahdi Majidi Ghodratollah Saeidi Hossein Alaei Vahid Rezaei 《Plant Breeding》2019,138(6):846-861
Possibility of using interspecific hybridization to increase genetic diversity of drought tolerance in safflower (Carthamus tinctorius L.) and effectiveness of different selection methods is poorly understood. The main objectives of this study were to evaluate the effectiveness of (a) interspecific hybridization to expand genetic diversity in safflower for agronomic traits and drought tolerance in advance generations and (b) different selection methods (direct vs. indirect) for improving seed yield. Interspecific hybridizations were performed between species of C. tinctorius × C. palaestinus (TP), C. palaestinus × C. oxyacantha (PO) and C. tinctorius × C. oxyacantha (TO). Based on the field screening of genotypes in F3 generation, four groups of selected genotypes (derived from combination of direct and indirect selection under both drought and normal environments along with selection based on drought tolerance index (STI)) were evaluated in F4 and F5 generations. Indirect selection for seed yield was significantly more efficient than direct selection. Selection in stress environment resulted to more efficiency than selection in normal environment. No significant difference was observed between direct selection and selection based on STI. The result showed that TP was the best population to combine high seed yield and drought tolerance in safflower. 相似文献
5.
Saeid Ghasemi Esfahlan Roghayeh Hemmati Shohreh Mohebbi Jacqueline Batley Mahdi Arzanlou 《Forest Pathology》2023,53(1):e12784
Trunk disease is a major problem on grapevine in Zanjan province, causing serious decline, despite which its aetiology remains unknown. The purpose of this study was to investigate factors involved in grapevine decline in vineyards of Zanjan province. Samples were collected from twigs and branches of grapevines in the region between October and November 2018. Fungal isolates were identified based on morphological characteristics and ITS-rDNA sequence data for selected isolates. The frequency and diversity of the fungal community recovered from grapevines in Darreh Sejin in Zanjan province were higher than in other regions. A total of 112 fungal isolates comprising 22 species were recovered. Phaeoacremonium minimum, Microsphaeropsis olivacea and Kalmusia variispora were identified as the dominant species in the region examined and could be considered the main trunk pathogens of grapevines in Zanjan region. In inoculation tests, M. olivacea was proved to be pathogenic on grapevine for the first time in this study. 相似文献
6.
Marjan?Jannatdoust Reza?DarvishzadehEmail author Roghayyeh?Ziaeifard Mohammad?Ali?Ebrahimi Hamid?Hatami?Maleki Esmaeel?Gholinezhad Ali?Asghar?Hatamnia 《Journal of Crop Science and Biotechnology》2016,19(1):37-44
Genetic diversity within and among 50 populations of confectionery sunflower (Helianthus annuus L.) collected from different geographical areas of Iran was evaluated by using microsatellite and retrotransposon markers. The number of alleles (Na) in SSR loci ranged from 2 to 3 with an average of 2.1. The polymorphic bands in retrotransposon markers ranged from 7 in locus CR-UR1 to 15 in locus CR-816 with a mean value of 11.33. Herarchical clustering of individuals (50 × 5 = 250) by neighbor joining method in DARwin5 software subdivided them into three groups. Using Bayesian method in the software pakage of Structure, the studied individuals were subdivided into two sub-populations. Principal coordinate analysis revelaed that the two first components explaine 7.86 and 6.16% of the total variance, respectively. Analysis of molecular variance revealed a higher level of genetic variation within (70%) than between (30%) populations. High molecular variation among individuals within population possibly is due to high allogamy nature of the sunflower plant. Low genetic variation observed between populations could be considered as a consequence of genetic equilibrium that has occurred over the long period of cultivation of confectionery sunflower in this area as well as seed exchange among regions. The traditional assumption that selecting genotypes of different geographical origin will maximize the diversity available to a breeding project does not hold in confectionery sunflower. 相似文献
7.
Nitrate leaching in a silage maize field under different irrigation and nitrogen fertilizer rates 总被引:4,自引:0,他引:4
Mahdi Gheysari Seyed Majid Mirlatifi Mehdi Homaee Gerrit Hoogenboom 《Agricultural Water Management》2009,96(6):946-954
Quantification of the interactive effects of nitrogen (N) and water on nitrate (NO3) loss provides an important insight for more effective N and water management. The goal of this study was to evaluate the effect of different irrigation and nitrogen fertilizer levels on nitrate-nitrogen (NO3-N) leaching in a silage maize field. The experiment included four irrigation levels (0.7, 0.85, 1.0, and 1.13 of soil moisture depletion, SMD) and three N fertilization levels (0, 142, and 189 kg N ha−1), with three replications. Ceramic suction cups were used to extract soil solution at 30 and 60 cm soil depths for all 36 experimental plots. Soil NO3-N content of 0-30 and 30-60-cm layers were evaluated at planting and harvest maturity. Total N uptake (NU) by the crop was also determined. Maximum NO3-N leaching out of the 60-cm soil layer was 8.43 kg N ha−1, for the 142 kg N ha−1 and over irrigation (1.13 SMD) treatment. The minimum and maximum seasonal average NO3 concentration at the 60 cm depth was 46 and 138 mg l−1, respectively. Based on our findings, it is possible to control NO3 leaching out of the root zone during the growing season with a proper combination of irrigation and fertilizer management. 相似文献
8.
The aim of this work was to evaluate the effective parameters for prediction of the electrospun gelatin nanofibers diameter using artificial neural network (ANN) technique. The various sets of electrospinning process including temperature, applied voltage and polymer and solvent concentrations were designed to produce pure gelatin nanofibers. The obtained results by analyzing Scanning Electron Microscopy (SEM) images indicated that the produced nanofibers diameter was in the range of 85 to 750 nm. Due to the volume of the data, k fold cross-validation method was used for data setting. Data were divided into the five categories and trained and tested using ANN technique. The results indicated that the network including 4 input variables, 3 hidden layers with 10, 18 and 9 nodes in each layers, respectively, and one output layer had the best performance in the testing sets. The mean squared error (MSE) and linear regression (R) between observed and predicted nanofibers diameter were 0.1531 and 0.9424, respectively. The obtained results demonstrated that the selected neural network model had acceptable performance for evaluating involved parameters and prediction of nanofibers diameter. 相似文献
9.
Khazaeel Kaveh Pesarakli Hamid Mashhadi Alireza Ghadrdan Borujeni Mahdi Pourmahdi 《Veterinary research communications》2022,46(2):405-417
Veterinary Research Communications - Accurate estimation of a horse's age based on the condition of the tooth status is necessary as a scientific and artistic technique, which has not been... 相似文献
10.
Cotton fabrics were dyed with three commercial vat dyes in order to provide camouflage in Vis-NIR regions and imitate reflectance profile of greenish leaves. To investigate the effect of nano particles on camouflage properties of dyed fabric, nano particles of TiO2 were applied on dyed fabrics using pad-dry-cure method. The nano TiO2 padded dyed fabrics were investigated using scanning electron microscopy (SEM). Reflectance curves of coated dyed samples with different concentrations of nano TiO2 were measured. Results showed that in both of the standard shades, nano TiO2 increases the reflectance value in NIR region and with increasing the concentration of nano TiO2, the reflectance curves of samples tend to show the maximum reflection of greenish leaves (deciduous leaves) in NIR region. Chromatic values (CIE1976 L*, a*, and b*) and color difference (according to CIECMC color difference ΔE*cmc (2:1)) of each of the coated samples were measured using the reflection spectrophotometer. By considering the influence of white color of nano TiO2 on green shade of dyed cotton fabrics and increasing the color difference (between coated samples and the standard shades of the 1948 U.S army pattern) in visible range, optimum concentrations of nano TiO2 for development of camouflage properties on cotton fabrics in both NIR and visible region were determined. These values for NATO and forest green shades were 0.75 % and 0.5 %, respectively. Fastness results showed that both of the samples have acceptable color fastness. The effect of washing and exposure to light on camouflage properties of coated dyed fabrics in visible (in term of chromatic values) and NIR region (in term of spectral reflectance) was investigated when those were coated in optimum concentrations of nano TiO2. The results showed that the effect of after treatments (washing and exposure to light) on surface color spectral characteristics and camouflage properties was inconsiderable. 相似文献