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11.
Evaluation of hyperimmune sera against goat pox viral antigens   总被引:1,自引:0,他引:1  
Tropical Animal Health and Production -  相似文献   
12.
Immunization against Angara disease virus (ADV), a serotype 4 avian adenovirus, and Newcastle disease virus (NDV), an avian paramyxovirus serotype 1, is the mainstay of a broiler vaccination programme, while polyether ionophores usually form an essential component of a broiler medication programme in most parts of India and Pakistan. The role of polyether ionophores in the protective immune responses of broiler chickens vaccinated and challenged with ADV and NDV was investigated. A total of 1600 birds were divided into eight groups of 200 birds each. First four groups were vaccinated against NDV and ADV, while the remaining four served as unvaccinated controls. The first 3 groups of birds were administered salinomycin, monensin and cyclophosphamide (CYP), respectively. The last group served as an untreated control. The same treatment schedule was also followed for the next four unvaccinated groups. The post-vaccination and post-challenge serological responses to NDV and ADV, body and lymphoid organ weight gains, post-challenge survival rate and detection of NDV and ADV in the tissues of infected birds were evaluated. Birds administered salinomycin showed a significant stimulation of protective immune responses against both NDV and ADV as compared to the untreated and CYP-treated birds. Monensin also enhanced the protective immune responses against both viruses but the effect was not statistically significant. Thus, it is concluded that monensin and salinomycin augment the anti-NDV and anti-ADV immune responses in broiler chickens, which supports their use in poultry flocks.  相似文献   
13.
Jai Gopal 《Euphytica》1993,72(1-2):133-142
Summary Six hundred and seventy six accessions of cultivated potato (Solanum tuberosum ssp. tuberosum) from 25 countries, were studied for flowering and fruiting behaviour under long days (12–14 h). Flowering intensity ranged from dropping of floral buds just after initiation to profuse blooming. The majority (58.3%) of the accessions bloomed profusely, though 20.4% of the accessions did not bloom at all. Weeks to flowering ranged from 6 to 15 and the majority (66.5%) of the flowering accessions bloomed within 8 to 9 weeks after planting. Duration of flowering ranged from 1 to 10 weeks and the majority (68.1%) of the flowering accessions bloomed for 1 to 4 weeks only. Twentythree per cent of the flowering accessions were completely male sterile. Maximum male fertility was 90% only. No berry setting was observed in 31.8% of the flowering accessions. Only 54.3 per cent of the accessions were found to be fertile in all respects and could be used both as male and female parents. Premature bud abscission was the major cause of sterility. Peru was the best source of profuse-flowering genotypes, Poland was the best source of early flowering genotypes and Mexico was the best source of long duration flowering and good berry setting genotypes. The results suggested that flower bud formation; the growth and development of mature flowers; weeks to flowering and duration of flowering are independent characters controlled by different genes of quantitative nature. Berry setting and duration of flowering were closely associated (r=0.95). Genetic as well as environmental factors interfered with the developmental process leading to flower production and berry setting at different times in different genotypes. The practical implications of these results for true potato seed production are discussed.Publication No. 1298, CPRI, Shimla.  相似文献   
14.
Correlation and path-coefficient analysis for leaf-anatomical characters affecting frost injury was carried out in twenty eight varieties and accessions belonging to several wild and cultivated tuber-bearing species of Solanum in order to identify selection criteria in breeding for frost resistance in potato Palisade thickness and palisade proportion showed a significant negative correlation with frost injury Path-coefficient analysis revealed that palisade thickness had the highest direct negative effect on frost injury whereas leaf thickness, not conforming to its behaviour as found in simple correlation analysis, emerged ax the next highest factor to have direct positive effect on frost injury. Direct and indirect effects of these factors on frost injury vis a vis their interdependence were found to be in support ot the ‘palisade thickness method’ for screening frost resistant genotypes in potato breeding programmes.  相似文献   
15.
Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini‐core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini‐core consisting of 98 genotypes was identified. Ninety‐four per cent of the alleles present in the core set were present in the mini‐core. The identified small but diverse panel will be useful for further intensive trait‐specific evaluation and utilization in allele mining.  相似文献   
16.
Eremostachys superba Royle ex Benth. (Lamiaceae) has undergone a severe decline in population size since its discovery in the North-western Himalayas in late 19th century. One hundred and seventy-two plants from six populations in the Indian states of Uttar Pradesh and Jammu & Kashmir, located between 0.45 km and 455.72 km apart from each other were evaluated for RAPD polymorphism. Sixteen random primers generated 92 bands overall, 77 of which were polymorphic. Shannon’s index of genetic diversity within populations (H o) ranged between 0.305 and 0.421; the average within-population diversity (H pop) was 0.389; and the total species diversity (H sp) was 0.478. The population from Mohand (representing the type locality) had the fewest plants, at 18, and was genetically the most depauperate. Among the other populations, ranging in size between 52 and 1,022 individuals, no relation between population size and genetic diversity was evident. It is suggested that these six populations represent relics of a larger, extended population, in which the presence of perennating rootstocks has helped preserve historic patterns of genetic diversity. AMOVA revealed that 83.01% of the variation exists within populations, which was consistent with earlier studies on the reproductive biology of E. superba, which indicated this species is predominantly allogamous. FST distances between all populations were significant, indicating geographic differentiation despite some of them being closely separated. Habitat restoration and protection from indiscriminate harvesting are proposed as primary strategies for conserving E. superba. Rejuvenation of the Mohand population through intrapopulation crossing between plants bearing diverse molecular phenotypes is also suggested.  相似文献   
17.
The reversible blockage of synthetic pores formed by rigid-rod beta barrels, either by substrates or products, was used to sense a variety of enzymatic reactions in high-throughput format with "naked-eye" fluorescent detection. Improvement of sensor sensitivity beyond three orders of magnitude by straightforward internal mutations underscores the functional plasticity of rigid-rod beta barrels. Such detectors of enzyme activity with the aforementioned characteristics are needed in areas as diverse as proteomics and environmentally benign organic synthesis.  相似文献   
18.
Here we studied the antiproliferative activity of theaflavins in cervical carcinoma HeLa cells by investigating their effects on cellular microtubules and purified goat brain tubulin. Theaflavins inhibited proliferation of HeLa cells with IC(50) value of 110 ± 2.1 μg/mL (p = < 0.01), caused cell cycle arrest at G(2)/M phase and induced apoptosis with alteration of expression of pro- and antiapoptotic proteins. Along with these antiproliferative activities, theaflavins act as microtubule depolymerizers. Theaflavins disrupted the microtubule network accompanied by alteration of cellular morphology and also decreased the polymeric tubulin mass of the cells. The polymerization of cold treated depolymerized microtubules in HeLa cells was prevented in the presence of theaflavins. In vitro polymerization of purified tubulin into microtubules was also inhibited by theaflavins with an IC(50) value of 78 ± 2.43 μg/mL (P < 0.01). Thus, disruption of cellular microtubule network of HeLa cells through microtubule depolymerization may be one of the possible mechanisms of antiproliferative activity of theaflavins.  相似文献   
19.
Finger millet [Eleusine coracana (L.) Gaertn.] is an important cereal food crop in Africa and South Asia. It is a hardy crop that can be grown in very diverse environments from almost at sea level to about 2400 m.a.s.l. Finger millet has an excellent food value as its seeds contain protein ranging from 7 to 14% and are particularly rich in methionine amino acid, iron, and calcium. Despite all these merits, this crop has been neglected from the main stream of crop improvement research. One of the means to boost its production and productivity is to enhance utilization of finger millet germplasm to breed superior varieties. Keeping this objective in view, a core subset of finger millet germplasm (622 accessions) based on origin and data on 14 quantitative traits was developed from the entire global collection of 5940 accessions held in the genebank at ICRISAT, Patancheru, India. The comparison of means, variances, frequency distribution, Shannon-Weaver diversity index (H′) and phenotypic correlations indicated that the core subset represents the entire collection. These tests indicated that sampling was optimal and the diversity has been captured very well in the core subset. The correlation analysis indicated that panicle exsertion and longest finger length could be given lower priority in the future germplasm evaluation work of finger millet.  相似文献   
20.
A study was carried out in Madhya Pradesh (Central India) to collect data on injury-causing agricultural incidents during the period 1995-1999. The overall incidence rate was 1.25/1000 workers/year. About 9.2% of the incidents were fatal, and most of the fatal incidents were due to tractors and snakebites (42.9% each). About 77.6% of all incidents were due to farm machinery, 11.8% were due to hand tools, and the remaining 10.6% were due to other sources like snakes, wells, etc. Data on 1,911 incidents reported in 10 leading newspapers published during the five-year period (1995-1999) from different regions of the state were also collected and analyzed, which indicated that only major or roadside agricultural incidents were reported in newspapers. Based on the survey data, it was estimated that in the year 2000 there would have been about 17,480 agricultural incidents in Madhya Pradesh, causing death to about 2,050 workers and injuries to about 16,770 workers, including amputations of limbs, burns, cuts, etc. Total monetary loss due to agricultural injuries in the state of Madhya Pradesh has been estimated as US $27 million/year.  相似文献   
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