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61.
62.
Hoque M Somvanshi R Singh GR Mogha IV 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(8):403-407
A total of 19 adult hill cattle of both sexes were subjected to trans-rectal ultrasound scanning of urinary bladder to evaluate bladder wall thickness and the presence of space-occupying lesions. The animals were divided into four groups. Eight apparently healthy hill cattle maintained under standard ration served as control (group I) and the remaining II animals were divided into three groups (II, III and IV). Group II animals (n = 8) were fed with different type of ferns which were further divided into subgroups II-P, -D and -B and fed with Polystichum squarrosom (n = 2). Dryopteris juxtaposita (n = 2) and Pteridium aquilinum (n = 4) ferns, respectively. The one animal in group III was a natural case of enzootic bovine haematuria (EBH) and the two animals in group IV were natural cases of microscopic EBH fed with Polystichum squarrosum fern. In group I animals, the average bladder wall thickness was 1.45 mm. The delineation of the bladder wall was uniformly smooth and the echo pattern of the bladder was homogeneously black, which was suggestive of clear urine content. In group II (P, D and B) the average bladder wall thickness of the six animals was 1.87 mm and the sonographic features were within normal limit when compared with controls. In two of the animals of group II-B, the bladder wall was apparently thick (4.36 mm) and there was no intraluminal mass except at one or two focal elevated points. Animals of groups III and IV showed the average bladder wall thickness of 4.86 mm and were characterized by the presence of irregular sessile masses extending into the bladder lumen. The homogeneous anechoic area was reduced centrally due to the presence of a hypoechoic soft tissue mass all around the bladder wall. Post-sonographic urinalysis, biopsy and necropsy of selected cases further confirmed the sonographic findings. 相似文献
63.
Polymerase chain reaction (PCR) was used to amplify the spacer regions between the 16S and 23S genes of rRNA genetic loci of Salmonella serovars for their rapid identification. These genetic loci revealed a significant level of polymorphism in length across the species/serovar lines. When the 16S-23S spacer region amplification products were subjected to agarose electrophoresis, the patterns observed could be used to distinguish all the serovars of Salmonella tested. Unique elements obtained in amplification products were mostly clustered at serovar level, although certain genus-specific patterns were also observed. On the basis of the results obtained, the amplification of 16S-23S ribosomal spacer region could suitably be used in a PCR-based identification method for Salmonella serovars. 相似文献
64.
65.
Tropical Animal Health and Production - 相似文献
66.
Bitter gourd or bitter melon (Momordica charantia L.) is considered as minor cucurbitaceous vegetable in spite of having considerable nutritional and medicinal properties. Although some reports on genetic diversity based on morphological characterization are available, no work has been conducted to estimate genetic diversity using molecular markers in this crop. In the present study, 38 genotypes of M. charantia including few commercially cultivars collected from different parts of India based on agro-ecological zones were analysed for diversity study both at morphological and molecular levels. Genomic DNA was extracted from young healthy leaves following the procedure of Doyle and Doyle [Doyle, J.J., Doyle, J.L., 1990. A rapid DNA isolation procedure from small quantity of fresh leaf material. Phytochem. Bull. 119, 11–15]. Pair-wise comparison of genotypes was calculated as per the procedure of Jaccard [Jaccard, P., 1908. Nouvelles recherches sur la distribution florale. Bull. Soc. Vaud. Sci. Nat. 44, 223–270]. Dendrogram was constructed using the unweighted pair group method with arithmetic averages (UPGMA) and the computation for multivariate analysis was done using the computer programme NTSYS-pc Version 2.0 [Rohlf, F.J., 1998. NTSYS-pc Numerical Taxonomy and Multivariate Analysis System, Version 2.01. Exeter Software, Setauket, NY, USA]. Diversity based on yield related traits and molecular analysis was not in consonance with ecological distribution. Among 116 random decamer primers screened 29 were polymorphic and informative enough to analyse these genotypes. A total of 208 markers generated of which 76 (36.50%) were polymorphic and the number of bands per primer was 7.17 out of them 2.62 were polymorphic. Pair-wise genetic distance (GD) based on molecular analysis ranged from 0.07 to 0.50 suggesting a wide genetic base for the genotypes. The clustering pattern based on yield related traits and molecular variation was different. 相似文献
67.
Parul Singh Anjil Kumar Srivastava Ashok Kumar Singh 《Pesticide biochemistry and physiology》2007,89(3):216-219
In this study, the comparison of cytogenetic effects of insecticide and fungicide in different phases of cell cycle was investigated in the root tip cells of barley (Hordeum vulgare L.). The seeds of H. vulgare L. Var. Karan 16 were treated with different concentrations (0.05%, 0.1% and 0.5%) of insecticide Profenophos (PF) and fungicide Mancozeb (MZ) for 6 h after presoaking durations of 7, 17 and 27 h.The different presoaking durations were used to bring the cells in various phases of cell cycle. Negative control was run parallel in distilled water. Cytogenetic examinations of root meristems exposed to the PF and MZ showed significant inhibition of mitotic index (MI) as well as significant increase in chromosomal aberrations (CAs). These parameters were dependent on the concentrations of insecticide and fungicide. The present study shows that PF and MZ both caused more damage in S phase of cell cycle which indicates that S phase is more sensitive in comparison to other phases. 相似文献
68.
The importance of reduced tillage in sustainable agriculture is well recognized. Reduced-tillage practices (which may or may
not involve retention of crop residues) and their effects differ from those of conventional tillage in several ways: soil
physical properties; shifts in host–weed competition; soil moisture availability (especially when sowing deeply or under stubble);
and the emergence of pathogen populations that survive on crop residues. There may be a need for genotypes suited to special
forms of mechanization (e.g. direct seeding into residues) and to agronomic conditions such as allelopathy, as well as specific
issues relating to problem soils. This article examines issues and breeding targets for researchers who seek to improve crops
for reduced-tillage systems. Most of the examples used pertain to wheat, but we also refer to other crops. Our primary claim
is that new breeding initiatives are needed to introgress favourable traits into wheat and other crops in areas where reduced
or zero-tillage is being adopted. Key traits include faster emergence, faster decomposition, and the ability to germinate
when deep seeded (so that crops compete with weeds and use available moisture more efficiently). Enhancement of resistance
to new pathogens and insect pests surviving on crop residues must also be given attention. In addition to focusing on new
traits, breeders need to assess germplasm and breeding populations under reduced tillage. Farmer participatory approaches
can also enhance the effectiveness of cultivar development and selection in environments where farmers’ links with technology
providers are weak. Finally, modern breeding tools may also play a substantial role in future efforts to develop adapted crop
genotypes for reduced tillage. 相似文献
69.
G. Girmay B. R. Singh H. Mitiku T. Borresen R. Lal 《Land Degradation \u0026amp; Development》2008,19(4):351-367
The effect of soil management and land use change are of interest to the sustainable land management for improving the environment and advancing food security in developing countries. Both anthropogenic changes and natural processes affect agriculture primarily by altering soil quality. This paper reviews and synthesizes the available literatures related to the influence of soil management and land use changes on soil carbon (C) stock in Ethiopia. The review shows that topsoil C stock declines approximately 0–63%, 0–23%, and 17–83% upon land use conversion from forest to crop land, to open grazing, and to plantation, respectively. An increase of 1–3% in soil C stock was observed within 10 years of converting open grazed land to protected enclosures. However, there was a little change in soil C stock below 20 cm depth. There is a large potential of increasing SOC pool with adoption of land restorative measures. Total potential of soil C sequestration with the adoption of restoration measures ranges 0·066–2·2 Tg C y−1 on rain‐fed cropland and 4·2–10·5 Tg C y−1 on rangeland. Given large area and diverse ecological conditions in Ethiopia, research data available in published literature are rather scanty. Therefore, researchable priorities identified in this review are important. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
70.
Comparative Expression Analysis of Gametogenesis‐Associated Genes in Foetal and Adult Bubaline (Bubalus bubalis) Ovaries and Testes 下载免费PDF全文
SM Shah N Saini S Ashraf M Zandi MK Singh RS Manik SK Singla P Palta MS Chauhan 《Reproduction in domestic animals》2015,50(3):365-377
This study was conducted to identify and analyse the expression of gametogenesis‐associated genes and proteins in foetal and adult buffalo gonads of both the sexes. Relative quantification of the genes was determined by qPCR and Western blotting. Immunohistochemistry was also performed for various gametogenesis‐associated proteins in foetal and adult gonads of both the sexes. We observed significantly (p < 0.05) increased expression of primordial germ cell‐specific, meiotic as well as genes associated with oocyte maturation and development in foetal ovaries as compared to the adult ones. However, significantly (p < 0.05) increased expression of proteins associated with oocyte maturation like GDF9 and ZP4 was found in adult ovaries, indicating temporal regulation of mRNA translation during oogenesis. Meiotic genes showed significantly (p < 0.05) increased expression in adult testes as compared to foetal testes and ovaries, indicating onset of meiosis at a later stage in spermatogenesis. In general, the expression of primordial germ cell‐associated as well as meiotic genes was higher in adult testes, indicating the increased biological activity in the organ. Immunohistochemistry revealed localized expression of gametogenesis‐associated proteins in ovarian follicles and seminiferous tubules of testes, while the surrounding somatic tissues were devoid of these proteins. The study gives an understanding of the sequential and temporal events of gene expression as well as mRNA translation during male and female gametogenesis. It could also be concluded that follicles and seminiferous tubules are the functional units of the female and male gonads, respectively, and their function could be enhanced by appropriate chemical and genetic intervention of the somatic tissue immediately surrounding them. This assumes importance in the context that buffalo attains sexual maturity at an older age of 2–3 years and have smaller ovaries with lesser number of primordial follicles in comparison with cattle, which is suggested to be the main reason of their poor breeding performance. 相似文献