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51.
K. Das Mahapatra B. Gjerde P.K. Sahoo J.N. Saha A. Barat M. Sahoo B.R. Mohanty J.
degrd M. Rye R. Salte 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):29-34
A challenge test against Aeromonas hydrophila was conducted using 2062 rohu carp (Labeo rohita) fingerlings obtained from 52 dams and 87 sires (87 full-sib families) of two year-classes (2003 and 2004). Attempts to establish a cohabitant challenge model were not successful. Therefore, fish were challenged by intraperitoneal injection with A. hydrophila in two replicate tanks per year-class, and dead fish were collected hourly. The mortality reached its peak at 16–22 h after challenge and had almost completely stopped after 58 h. The test was terminated after 382 h at which the average survival was 43.9 and 48.9% in the two 2003 year-class tanks, and 77.1 and 35.8% in the two 2004 year-class tanks. Heritability estimates for survival were obtained from sire and dam threshold models (THR) and sire and dam linear repeatability models (LINR). For both types of models the heritability estimates based on data from single tanks were not consistent. For both year-classes, data from one of the two challenged tanks demonstrated significant additive genetic variation in survival during the A. hydrophila infection, whereas the heritability estimates were not significantly different from zero for the other tank. Further, genetic correlation between survivals in the two replicate tanks in each year-class was not significantly different from zero. The differential results from the replicate tanks demonstrate that additional challenge test experiments are needed before firm conclusions can be drawn about the magnitude of additive genetic variation for survival to aeromonasis in rohu carp. A cohabitant challenge model that allows the testing of important defence mechanisms in the skin and mucous membranes of the fish might have been more appropriate. To establish a valid cohabitant challenge model for rohu carp should be given high priority. 相似文献
52.
M. Das P. H. Zaidi M. Pal & U. K. Sengupta 《Journal of Agronomy and Crop Science》2002,188(4):219-224
An experiment was undertaken using open‐top chambers to study the effect of CO2 enrichment on crop growth and to assess the variation related to the time of CO2 exposure. In general, enriched CO2 conditions (600 ± 50 p.p.m.) in the chamber positively affected the growth and development of mungbean (Vigna radiata), a short‐duration (60–65 days) summer pulse crop. However, there was significant variability in the effect of the crop stage/time of CO2 exposure. It was observed that high CO2 exposure at an early growth stage [0–20 days after germination (DAG)] had a larger effect than that at a later growth stage (21–40 DAG). The experiment also provided a means of assessing the short‐ and long‐term effects of elevated CO2 on the carbon exchange rate at both stages of exposure. The study revealed that the sensitivity of plants to high CO2 was more pronounced with respect to net photosynthetic rate. The overall photosynthetic activity gave greater growth and development of plants under high CO2. 相似文献
53.
K N Gelatt D A Samuelson J E Bauer N D Das E D Wolf K P Barrie T L Andresen 《American journal of veterinary research》1983,44(6):1130-1132
Congenital cataracts and microphthalmia in the Miniature Schnauzer were inherited as an autosomal recessive trait. Eighteen matings of affected X affected Miniature Schnauzers resulted in 87 offspring with congenital cataracts and microphthalmia (49 males/38 females). Two matings of congenital cataractous and microphthalmic Miniature Schnauzers (2 females) X a normal Miniature Schnauzer (1 male) yielded 11 clinically normal Miniature Schnauzers (7 males/4 females). Eighteen matings of congenital cataractous and microphthalmic Miniature Schnauzers (6 males) X carrier Miniature Schnauzers (9 females) produced 81 offspring; 39 exhibited congenital cataracts and microphthalmia (20 males/19 females) and 42 had clinically normal eyes (17 males/25 females). 相似文献
54.
A study was made to induce flowering in an “off-year” in the strictly irregularly-bearing mango cultivar ‘Langra’. Cycocel 3000 mg/l on ringed shoots produced the largest number of flower panicles (62.3%), whereas the control recorded the lowest number (8%). MH-1500 mg/l with ringing reduced the length of the shoot, increased the diameter of the shoots, and greatly reduced the vegetative growth. All the treatments produced quite good percentages of flower buds in comparison to the control, and enhanced the flowering-time. With CEPA 400 mg/l the flowering-time was enhanced by 16 days. 相似文献
55.
Available moisture release characteristics for two well aggregated clayey forest soils of West Bengal (INDIA) were determined with respect to different-sized water-stable aggregates. In situ determination of higher range of available moisture differed appreciably from classic 1/3 bar moisture retention, for the soils. Release of moisture at lower tensions (0.33 > bar) were mainly governed by the inter-aggregate pore size distribution while that at higher tension chiefly attributed to the texture of aggregates i.e. the intra-aggregate pore size distribution. The difference in moisture releasing capacity particularly in the range 0.33—15.0 bar amongst different sized aggregates, was due mainly to varying amount of clay and organic carbon in different-sized aggregates. 相似文献
56.
Peter J. Smith Alan J. Crowe V. G. Kumar Das John Duncan 《Pest management science》1979,10(5):419-422
Bioassay data are reported for 12 organotin compounds, R3SnX, against the adult snail, Biomphalaria glabrata, an intermediate host of schistosomiasis. The relationship between the molluscicidal activity and the nature of the R and X groups in the organotin compounds is discussed, as well as the possible mode of toxic action of these compounds. 相似文献
57.
58.
(1) A comparative study on the effect of different surface decontaminants: hot water at 70 degrees C for one minute; 2% lactic acid for 30 s; 1200 p.p.m. acidified sodium chlorite (ASC) solution for 5 s and 50 p.p.m. chlorine solution for 5 min in the form of dips and sprays on the surface of dressed broilers for 0, 24 and 48 h of storage was conducted. (2) The variables studied were, total plate count (TPC), presumptive coliform count (PCC), pH and extract release volume (ERV). All treatments reduced TPC and PCC. (3) Lactic acid dip and hot water dip were the most effective for reducing TPC (1.36 and 1.28 log/cm2, respectively) with no significant difference between them. (4) ASC and hot water in dip could diminish PCC (1.37 and 1.34 log/cm2, respectively) and did not vary significantly. (5) No treatment affected muscle pH, water holding capacity (WHC), ERV, appearance, smell, tenderness and overall acceptability of treated broilers significantly. (6) Hot water treatment is the cheapest, most convenient and simplest decontamination technique for hygienic and wholesome poultry production. 相似文献
59.
Falchi M Bertelli A Lo Scalzo R Morassut M Morelli R Das S Cui J Das DK 《Journal of agricultural and food chemistry》2006,54(18):6613-6622
Recent studies have documented that grapes and grape juices are equally cardioprotective as red wine. The existing reports implicate that the skin and seeds of the grapes containing polyphenolic antioxidants are instrumental for the cardioprotective properties of grapes. The present study examines if the flesh of grapes also possesses any cardioprotective abilities. Three groups of randomly selected rats were fed, water only (control), flesh of the grapes (2.5 mg/kg b. wt.) or the skins (2.5 mg/kg b. wt.) for 30 days. At the end of the 30 days, isolated perfused hearts were made ischemic for 30 min followed by 2 h of reperfusion in the working mode. The results demonstrated that both flesh and skin of the grapes could protect the hearts from ischemic reperfusion injury as evidenced by improved postischemic ventricular recovery and reduced myocardial infarct size. High performance liquid chromatography (HPLC) revealed that skin and flesh contained comparative amounts of glucose, fructose, tartaric acid, malic acid, shikimic acid, and trans-caftaric acid. In addition, the flesh contained reduced amounts (compared to skin) of cis-coutaric, trans-coutaric, caffeic, p-coumaric, cinnamics, and catechin/epicatechin. Total polyphenolic index was also lower in flesh compared to skin. The anthocyanins were present exclusively in the skin. Electron paramagnetic resonance (EPR) spectrometry of hydroxy radicals indicated that both flesh and skins possessed equal amount of ROS scavenging activities. Total malonaldehyde content in the heart was reduced comparatively with either flesh or skin. The results indicate for the first time that the flesh of grapes are equally cardioprotective as skin, and antioxidant potential of skin and flesh of grapes are comparable with each other despite of the fact that flesh does not possess any anthocyanin activities. 相似文献
60.
Rajkhowa S Shakuntala I Pegu SR Das RK Das A 《Tropical animal health and production》2012,44(7):1497-1503
Pasteurella multocida has been recognized as an important veterinary pathogen for over a century. Conventional methods for diagnosis of pasteurellosis rely on the detection of the organism by microscopy and its isolation and identification. However, as far as pasteurellosis is concerned, it is not just sufficient to know the identity of the organism. To constitute effective control measures, it is important to know the serotype of the organism. A study was undertaken to characterize the Pasteurella isolates from local pigs in India with clinical respiratory disease by determination of their capsule types and presence or absence of toxin gene. Pasteurella could be isolated from 66.70% of pigs with clinical respiratory disease. All the isolates were confirmed through biochemical characterization and P. multocida-specific polymerase chain reaction. It has also been observed that all the isolates belonged to capsular type D. All the isolates were sensitive to chloramphenicol, chlortetracycline, doxycycline, and enrofloxacin, while the rest of the antibiotics were less effective. It has also been observed that all isolates were resistant to cephalexin, penicillin G, and sulphadiazine. The study revealed the detection of P. multocida serotype D from clinical respiratory diseases of local pigs of India, which could be one of the important respiratory tract pathogens responsible for mortality of local pigs in India. 相似文献