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41.
Kumar AM Murtaugh R Brown D Ballas T Clancy E Patronek G 《Journal of veterinary medical education》2001,28(2):73-77
A donor program for procuring dogs and cats to meet the needs of anatomical instruction was initiated six years ago at Tufts University School of Veterinary Medicine. The program was initiated in order to comply with state regulations that preclude the use of shelter animals and to satisfy ethical objections of students and faculty. The donor program has successfully met the animal needs for teaching gross anatomy and, in addition, provides opportunities to integrate clinical perspectives and ethics beginning from the first year of veterinary education. 相似文献
42.
Ramamoorthy Saraswathy Moturi Muralidhar Das Sanjoy Periyamuthu Kumararaja Sukumaran Suvana Natarajan Lalitha Vinaya Kumar Katneni Arunachalam Nagavel Koyadan Kizhakedath Vijayan 《Aquaculture Research》2019,50(4):1096-1106
The health of the pond environment in shrimp farming is important for sustainable and profitable aquaculture, in which sediment–water interface is the most important influencing area. With this objective, the key parameters of water and sediment at the interface was studied in shrimp ponds with varying salinities and compared with the surface water and soil to understand the variations and the underlying causes. Total ammonia nitrogen and total alkalinity were higher in water at the interface as compared to surface water, whereas pH, nitrite, oxide forms of nitrogen (NO3), phosphorus (PO4) and oxidizing bacteria were observed to be lower. There was no significant difference with respect to macrominerals such as sodium, potassium, calcium and magnesium between water at the interface and surface. These changes are profoundly influenced by the uppermost 1.0‐cm thick sediment layer, where the maximum transition of nutrients takes place with the water column. The outcome of the study highlights the effectiveness of water sampling for metabolites at the interface, which reflects at an early stage any potential deterioration of pond environment, which will help the farmer to initiate timely mitigation measures. 相似文献
43.
Sanjay Singh Rathore Kapila Shekhawat Om Prakash Premi Basant Kumar Kandpal Jitendra Singh Chauhan 《Weed Biology and Management》2014,14(3):145-158
Broomrapes (Phelipanche and Orobanche spp.) are obligate root parasites of the family Orobanchaceae. The natural variation in Orobanchaceae exists in plants involving Triphysaria versicolor (facultative hemiparasite), Striga hermonthica (obligate hemiparasite) and Phelipanche aegyptiaca, formerly Orobanche aegyptiaca (holoparasite). The family Orobanchaceae has 90 genera. The four major parasitic species of broomrape are Phelipanche ramosa in the Brassicas, especially in rapeseed, Phelipanche cernua in tobacco and sunflower, P. aegyptiaca in solanacious crops and in Brassica juncea and Phelipanche crenata in leguminous crops. They are prevalent, infesting nearly 1.2% of the world's arable land. In India, P. ramosa and P. aegyptiaca cause severe infestations of Brassica and have threatened its cultivation in major growing areas. In addition, a single broomrape plant can release >100 000 seeds that remain viable for decades in the soil. This provides the parasite with a great genetic adaptability to environmental changes, including host resistance, agronomical practices and herbicide treatments. Different control measures, such as manual weeding, herbicide applications, solarization, crop rotation and integrated broomrape management practices, have been proposed in order to reduce the broomrape menace and improve yields in farmers' fields. Breeding for broomrape resistance also could be an economic, feasible and environmental friendly control method. The present article reviews the current status of research on broomrape in India and abroad, as well as suggests strategies for its effective management. 相似文献
44.
Only a little is known about the studies done with filariasis in relation to blood groups. The present communication reports the results of a preliminary study carried out to investigate any relationship of ABO and Rho(D) blood groups in persons with circulating microfilariae (mf) in blood and with disease manifestations compared with healthy normal controls within a population in similar epidemiological and ecological conditions. Blood groups ABO and Rho(D) were investigated among 271 persons with filarial disease and 172 normal subjects from an endemic area of bancroftian filariasis. No relationship was observed between infection and blood groups. It appeared that blood groups and filarial infection were independent of each other. Also the sex of the individual and stage of the infection, i.e. persons with circulating mf only without manifestations and persons with established manifestation without mf, has no bearing on blood group inheritance. There were 95.05% of Rh-positive and 4.95% of Rh-negative persons in the whole studied population. The observations are similar to other studies. 相似文献
45.
Purushottam Kaushik Dhirendra K. Singh S. Vinoth Kumar Ashok K. Tiwari Gunjan Shukla Shanker Dayal Pallav Chaudhuri 《Veterinary research communications》2010,34(2):119-132
Brucella abortus, a gram negative, facultative intracellular pathogen causes brucellosis in many animal species and humans. Although live,
attenuated vaccines are available against this infection, they suffer from certain limitations. Therefore, the development
of an effective subunit vaccine against brucellosis is an area of intense research. The outer membrane proteins (OMPs) of
Brucella species have been extensively studied for its immunogenicity and protective ability. We have investigated the potential of
CpG ODN to enhance the immunogenicity and protective efficacy of recombinant 28 kDa outer membrane protein (rOMP28) of Brucella melitensis. The study demonstrated vigorous immunoglobulin G (IgG) response of OMP28. The administration of rOMP28 with CpG caused increased
cell mediated immune response in terms of induced IgG2a, T-cell proliferation and up-regulation of type I cytokine expression.
In contrast, the free antigen suppressed the interferon gamma (type I cytokine) production on in-vitro stimulation of spleenocytes.
The result indicates the role of OMP28 in the down regulation of IFN-γ production. Moreover, the B. abortus S-19 vaccinated mice showed highest production of IL-4 and IFN-γ. The protective ability of the antigen was evaluated by
systemic bacterial clearance after challenging the mouse with B. abortus 544 pathogen. The level of protection was significant in rOMP28+CpG treated mice but was lower than the required level. The
results of the present study indicate that rOMP28 could be an immunogen capable of inducing both humoral and cellular immune
response. The humoral response was biased towards Th1 type when it was co-administered with CpG. 相似文献
46.
Padmanav Routray Surjya Narayan Dash Chidananda Dash Priyabrat Swain Sampad Kumar Sarkar Niranjan Sarangi 《Aquaculture Research》2008,39(15):1597-1605
The effects of extender composition, cryoprotectant concentration and freezing and thawing on the fertilization efficiency of cryopreserved spermatozoa of Puntius gonionotus were evaluated. Computer‐aided motility analysis of semen was conducted to check the suitability of spermatozoa for cryopreservation after mixing with different extenders and cryoprotective agents (CPAs). Extender‐4 with an osmolality 260 mOsmol kg−1and pH 7.6 was used for the cryopreservation study. Among the CPAs, dimethyl sulphoxide (DMSO) was least toxic and more than 60% fertilization was achieved when used at 1.4 M at 0 °C for 10 and 30 min, whereas the toxicity of all CPAs to spermatozoa was evident when tested at 30 °C. Semen frozen at −16 °C min−1 with 1.4 M DMSO showed 70% fertilization, which was significantly higher (P<0.05) than other freezing rates. Samples thawed at 35 °C water showed a fertilization rate comparable with that of fresh semen. Computer‐assisted semen analysis of fresh and frozen semen after thawing showed variations in different types of motility in spermatozoa and in their class. There was no significant difference in motility before or after cryopreservation; however, significant differences could be observed in the average path velocity (VAP), straight line velocity (VSL) and curve linear velocity (VCL). Semen of silver barb could be cryopreserved with extender‐4 by addition of 1.4 M DMSO to a final cryopreservation medium (MED 2) cooled at a rate of −16 °C min−1, stored in liquid nitrogen (−196 °C) and utilized after thawing at 35±2 °C. 相似文献
47.
Effect of miconazole nitrate on immunological response and its preventive efficacy in Labeo rohita fingerlings against oomycetes Saprolegnia parasitica 下载免费PDF全文
Mukta Singh Ratan Kumar Saha Himadri Saha Janmejay Parhi 《Journal of fish diseases》2018,41(10):1539-1548
This study evaluated the effect of sublethal doses of antifungal drug miconazole nitrate (MCZ) on immunological responses and its role as a prophylactic drug against S. parasitica in Labeo rohita fingerlings. Fish were fed with sublethal doses of MCZ, that is, T1—6.30 mgMCZ kgBW?1, T2—12.61 mgMCZ kgBW?1 and T3—25.22 mgMCZ kgBW?1, and sampling was done at different time intervals for 240 hr. Immunological parameters viz. lysozyme activity, oxygen radical production and plasma antiprotease activity showed significant enhancement (p < 0.05) in fish fed with T2 and T3 doses. Expression of immune‐relevant genes such as TLR‐22 and β2‐M showed significantly higher expression at 6 hr and 24 hr of sampling in both liver and head kidney. However, these genes showed a downregulation after 120 hr of sampling in both the tissues. Preventive efficacy study showed that single dose of MCZ provides protection against oomycetes up to the fourth day of infection. Significantly higher mortality was observed in control diet‐fed fish as compared to fish fed with MCZ medicated diet. Thus, it can be concluded that the MCZ can act as a potent antifungal agent for preventing oomycetes infection as well as to enhance the immune response. 相似文献
48.
Venkatathalam Dinakaran Vinod Kumar Dumka Bibhuti Ranjan Ramalingam Balaje Pritam Kaur Sidhu 《Tropical animal health and production》2013,45(7):1509-1512
Disposition following single intravenous injection (2 mg/kg) and pharmacodynamics of cefquinome were investigated in buffalo calves 6–8 months of age. Drug levels in plasma were estimated by high-performance liquid chromatography. The plasma concentration–time profile following intravenous administration was best described by a two-compartment open model. Rapid distribution of cefquinome was evident from the short distribution half-life (t ½α ?=?0.36?±?0.01 h), and small apparent volume of distribution (Vdarea?=?0.31?±?0.008 L/kg) indicated limited drug distribution in buffalo calves. The values of area under plasma concentration–time curve, elimination half-life (t ½β ), total body clearance (ClB), and mean residence time were 32.9?±?0.56 μg·h/mL, 3.56?±?0.05 h, 60.9?±?1.09 mL/h/kg, and 4.24?±?0.09 h, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration of cefquinome were 0.035–0.07 and 0.05–0.09 μg/mL, respectively. A single intravenous injection of 2 mg/kg may be effective to maintain the MIC up to 12 h in buffalo calves against the pathogens for which cefquinome is indicated. 相似文献
49.
The photochemical degradation of the herbicide isoproturon in aqueous and non-aqueous solutions and in soils has been investigated. Four new photometabolites were formed in non-aqueous solution and three in soil. These were characterised by spectroscopic methods and identified by comparison with authentic synthetic samples such as 3-(4-isopropylphenyl)-1-methylurea; 3-(4-isopropylphenyl)urea; 4,4′-diisopropylazobenzene and 4,4′-diisopropylazoxybenzene. The pathway of formation of these photo products is depicted. 相似文献
50.
H. Nayyar G. Kaur S. Kumar H. D. Upadhyaya 《Journal of Agronomy and Crop Science》2007,193(5):336-344
Chickpea is sensitive to cold conditions (<15 °C), particularly at its reproductive phase and consequently it experiences significant decrease in the seed yield. The information about the effects of cold stress on chickpea during the seed filling phase is lacking. Moreover, the underlying metabolic reasons associated with the low temperature injury are largely unknown in the crop. Hence, the present study was undertaken with the objectives: (i) to find out the possible mechanisms leading to low temperature damage during the seed filling and (ii) to investigate the relative response of the microcarpa (Desi) and the macrocarpa (Kabuli) chickpea types along with elucidation of the possible mechanisms governing the differential cold sensitivity at this stage. At the time of initiation of the seed filling (pod size ∼1 cm), a set of plants growing under warm conditions of the glasshouse (temperature: 17/28 ± 2 °C as average night and day temperature) was subjected to cold conditions of the field (2.3/11.7 ± 2 °C as average night and day temperature), while another set was maintained under warm conditions (control). The chilling conditions resulted in the increase in electrolyte leakage, the loss of chlorophyll, the decrease in sucrose content and the reduction in water status in leaves, which occurred to a greater extent in the macrocarpa type than in the microcarpa type. The total plant weight decreased to the same level in both the chickpea types, whereas the rate and duration of the seed filling, seed size, seed weight, pods per plant and harvest index decreased greatly in the macrocarpa type. The stressed seeds of both the chickpea types experienced marked reduction in the accumulation of starch, proteins, fats, crude fibre, protein fractions (albumins, globulins, prolamins and glutelins) with a larger decrease in the macrocarpa type. The accumulation of sucrose and the activity levels of the enzymes like starch synthase, sucrose synthase and invertase decreased significantly in the seeds because of the chilling, indicating impairment in sucrose import. Minerals such as calcium, phosphorous and iron as well as several amino acids (phenylalanine, tyrosine, threonine, tryptophan, valine and histidine) were lowered significantly in the stressed seeds. These components were limited to a higher extent in the macrocarpa type indicating higher cold sensitivity of this type. 相似文献