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排序方式: 共有108条查询结果,搜索用时 31 毫秒
1.
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   
2.
This experiment was conducted to study the effect of different levels of wheat roti (WR) on nutrient utilization and blood metabolites in Asian elephants fed roughages ad libitum. Nine (3 M, 6 F) Asian elephants (14–52 years of age, 1909–3968 kg BW) were used in an experiment based on replicated Latin square design. Animals in each group (n = 3) were assigned to one of the three dietary treatments in a manner that animals in all the three groups were exposed to all the three treatments in three different periods. Each feeding trial comprised 30 days (25 days of adaptation and 5 days collection period). The amount of WR fed to the elephants was 0.18, 0.12 and 0.06% of BW in groups I, II and III, respectively. They were allowed to forage in the nearby forests for 6 h/day and to bathe for 2 h/day. The animals had ad libitum access to cut Rohini (Mallotus philippensis) trees in their night shelter. Intake and apparent digestibility of dry matter (DM), crude protein (CP), gross energy (GE), Ca, P, Fe, Cu and Zn were measured. Feed consumption was not significantly different among the groups. Significant (p < 0.01) decrease in digestibility of DM and GE and blood glucose concentration was observed with decreased level of WR in the diet. Feeding of WR at 0.06% of BW supplied adequate amount of DE, CP, Ca, P, Fe, Cu and Zn to meet requirement for adult maintenance. Feeding of WR in excess of 0.06% of BW supplied DE in excess of requirement, increased blood glucose concentration which may cause obesity and other associated health problems. It was concluded that the amount of WR should be restricted to 0.06% of BW in the diet of captive Asian elephants.  相似文献   
3.
The genetic bases of leaf rust resistance in wheat (Triticum aestivum L.) line CSP44, selected from the Australian cultivar Condor, and Indian cultivar VL404, were studied. The reaction patterns of CSP44 and VL404 against Indian races 12, 77, 77-1, 77-2, 77-3, 77-4, 77-5 and 108 were different from reaction patterns shown by near-isogenic lines with known adult plant resistance (APR) genes, viz. Lr12, Lr13, Lr22b and Lr34. Although the reaction patterns of CSP44 and VL404 were similar to the near-isogenic line Tc+Lr22a, tests of allelism indicated absence of Lr22a in both CSP44 and VL404. On the basis of genetic studies, their resistances in field tests against race 77-5, the most virulent race from the Indian sub-continent, were each ascribed to two genes. One of the two genes in each wheat was identified to be the non-hypersensitive APR gene Lr34. The second APR genes in CSP44 and VL404 gave hypersensitive reaction types and were recessive and dominant, respectively. The gene in CSP44 was designated Lr48and the gene in VL404, Lr49. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
4.
Segregation for salinity tolerance and ISSR markers based molecular polymorphism were investigated in a F3 plant population raised via single-seed descent method from a cross between salt-tolerant indica rice variety CSR10 and salt-susceptible premium traditional Basmati rice variety Taraori Basmati HBC19. A total of 130 F3plants were evaluated individually for salinity tolerance on 1–9 scale on the basis of seedling growth parameters; the average score ranged between 1.7 to 8.3. Frequency distribution curve obtained using the salinity tolerance data of F3 population and a chi-square analysis, showed a good fit to a normal distribution. Eleven plants each in the category of salt-tolerant and salt-susceptible were selected from the segregating F3 population for ISSR marker analysis. A total of 149 bands (4–11 bands per primer) ranging from 200 to 3530 bp were scored for the two rice varieties and the selected CSR10 × HBC19 segregating F3 plants using 26 ISSR primers. Of these, 89 were monomorphic and 60 were polymorphic. Of the 60 polymorphic bands,36 and 20 bands were specific to CSR10 andHBC19 respectively. The remaining four bands were amplified using UBC primers 810,848, 853 and 886 and present in only some of the CSR10 × HBC19 F3 plants. Notably, ISSR primers with dinucleotide repeat motif and 5'-anchored end amplified more number of bands (7.0 bands/primer) compared to3'-anchored dinucleotide primers (5.4bands/primer), but 3'-anchored dinucleotide primers revealed higher level of polymorphism (2.6 polymorphic bands/primer) compared to 5'-anchoreddinucleotide primers (1.43 polymorphic bands/ primer). While distribution of majority of the polymorphic bands were more or less in the expected ratios in salt-tolerant and/or salt-sensitive F3segregating plants, but some of the bands amplified using UBC ISSR primers 823, 825,826, 849, 853, 864, 866 and 884 showed highly skewed distribution. Such polymorphic bands stand greater chances of having a linkage with the genes/ QTLs for salinity tolerance and shall be the target for further studies. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
5.
The genetics of resistance to three Indian pathotypes of Xanthomonas campestris pv. oryzae, namely, IX01, IX08 and IX09, was studied in a landrace of Indica rice ‘ARC 10464’. Resistance to each of the two pathotypes IX01 and IX09 was governed by two independently-inherited dominant genes while a single dominant gene was operative against patho-type 1X08. The joint segregation tests conducted on F2 plant progenies (F3 families) using pathotypes IX01, IX08 and IX09 suggested that the gene/(s) effective against each of the pathotypes are different.  相似文献   
6.
With increasing concern about declining water resources, there is increasing thrust in improving water management in farming systems to improve water use efficiency. The present investigation was undertaken to determine the optimum timing for the first and last irrigation of cotton on the basis of meteorological approach for scheduling irrigations. The experiment was conducted in a split plot design with three timings of first irrigation as main-plots and three timing of last irrigation as sub-plots. Delay of first irrigation from 28 days after sowing (DAS) to 42 DAS, irrespective of last irrigation, resulted in an increase of 8, 14 and 17% in seed cotton yield during first, second and third year, respectively. The corresponding increases due to delay in the last irrigation from 130 to 170 DAS were 14, 32 and 8%, respectively. On the basis of 3 years average, application of first and last irrigation at optimum time (after 42 and 170 days after sowing) resulted in an increase of 36% in seed cotton yield without involving any additional cost. Water expense efficiency (WEE) increased by 54%.  相似文献   
7.
The diagnosis and treatment of double intestinal intussusception in 3 pups with persistent vomiting, diarrhea, dehydration, anemia, leucocytosis, and electrolyte imbalance are described. Ultrasonography confirmed intussusception and laparotomy revealed double intussusceptions. Intussusceptions were corrected by manual reduction in 1 pup and intestinal resection and anastomosis in 2 pups. Two pups survived and 1 pup died on the 4th day after surgery.  相似文献   
8.
The humoral immune response and immunity conferred in chicks were compared following separate and combined oral vaccination with F strain of Newcastle disease virus (NDV) and HP1 strain of fowl pox virus. The haemagglutination inhibition (HI) antibody titre against NDV and passive haemagglutination (PHA) antibody titre against fowl pox virus were comparable in two respective groups. The serum IgG concentration increased significantly after the second vaccination in all the groups. The NDV vaccine induced significantly higher IgG production as compared to fowl pox virus vaccine. There was no significant difference in serum IgG concentration produced by combined vaccine and separate F strain vaccine. The protection afforded by combined and separate vaccinations did not vary significantly against challenge with virulent strains of NDV and fowl pox virus at different stages.  相似文献   
9.
Molecular markers provide novel tools to differentiate between the various grades of Basmati rice, maintain fair-trade practices and to determine its relationship with other rice groups in Oryza sativa. We have evaluated the genetic diversity and patterns of relationships among the 18 rice genotypes representative of the traditional Basmati, cross-bred Basmati and non-Basmati (indica and japonica) rice varieties using AFLP, ISSR and SSR markers. All the three marker systems generated higher levels of polymorphism and could distinguish between all the 18 rice cultivars. The minimum number of assay-units per system needed to distinguish between all the cultivars was one for AFLP, two for ISSR and five for SSR. A total of 171 (110 polymorphic), 240 (188 polymorphic) and 160 (159 polymorphic) bands were detected using five primer combinations of AFLP, 25 UBC ISSR primers and 30 well distributed, mapped SSR markers, respectively. The salient features of AFLP, ISSR and SSR marker data analyzed using clustering algorithms, principal component analysis, Mantel test and AMOVA analysis are as given below: (i) the two traditional Basmati rice varieties were genetically distinct from indica and japonica rice varieties and invariably formed a separate cluster, (ii) the six Basmati varieties developed from various indica × Basmati rice crosses and backcrosses were grouped variably depending upon the marker system employed; CSR30 and Super being more closer to traditional Basmati followed by HKR228, Kasturi, Pusa Basmati 1 and Sabarmati, (iii) AFLP, ISSR and SSR marker data-sets showed moderate levels of positive correlation (Mantel test, r = 0.42–0.50), and (iv) the partitioning of the variance among and within rice groups (traditional Basmati, cross-bred Basmati, indica and japonica) using AMOVA showed greater variation among than within groups using SSR data-set, while reverse was true for both ISSR and AFLP data-sets. The study emphasizes the need for using a combination of different marker systems for a comprehensive genetic analysis of Basmati rice germplasm. The high-level polymorphism generated by SSR, ISSR and AFLP assays described in this study shall provide novel markers to differentiate between traditional Basmati rice supplies from cheaper cross-bred Basmati and long-grain non-Basmati varieties at commercial level.The first two authors have equal contribution  相似文献   
10.
Seventeen diverse clones of sugarcane (Saccharum spp.) (7 early, 6 mid season and 4 late) were planted in October 1991 and 1992 in flooded (FE) and non flooded (NFE) environments for evaluation of cane yield, commercial cane sugar (CCS), internode length, internode number, stalk length, stalk thickness (circumference), stalk number, sugar recovery, and stalk weight. Cane yield showed significant positive phenotypic correlation coefficient (PCC) with stalk number in FE (P ≤ 0.05) and NFE (P ≤ 0.01). Stalk length had a significant positive PCC with stalk weight in both environments, and with internode length in FE (P ≤ 0.05). Commercial cane sugar also expressed significant positive PCC with cane yield in both environments (P ≤ 0.01), but with stalk number only in NFE (P ≤ 0.05). Genotypic correlation coefficients were generally in the same direction as PCC but higher in magnitude. In both environments, stalk number and stalk weight had relatively high positive direct effects on cane yield. However, flooding tended to enhance the direct effect of stalk weight and diminish the direct effect of stalk number on cane yield. Only cane yield and sugar recovery had high direct effects on CCS. Selection for improvement of cane yield can be based on stalk number and stalk weight in both environments. High yielding clones can be further screened for more sugar recovery to improve CCS. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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