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451.
452.
Raj Pal Singh Jitendra Kumar P. K. Dwarkanath D. S. Balaine 《British poultry science》1983,24(4):477-482
1. The housing system, age of pullets and their interaction had a significant effect on plasma 5'‐nucleotidase and alkaline phosphatase activities.
2. Activities were higher in birds in cages than in those on the floor, reflecting perhaps the stress of caging. Activities increased with age.
3. Activities were higher in pullets selected for higher production.
4. The type of housing had no effect on egg production, but age at first egg, egg weight and 40‐week body weight were found to be affected significantly. 相似文献
453.
Pallavi Bhardwaj Pritam K. Sidhu Simrat Pal Singh Saini Dinesh M.B. Satyavan Rampal 《Journal of veterinary pharmacology and therapeutics》2019,42(4):430-439
The pharmacokinetics (PK) and pharmacodynamics (PD) of marbofloxacin (MBF) were determined in six healthy female goats of age 1.00–1.25 years after repeated administration of MBF. The MBF was administered intramuscularly (IM) at 2 mg kg?1 day?1 for 5 days. Plasma concentrations of MBF were determined by high‐performance liquid chromatography, and PK parameters were obtained using noncompartmental analysis. The MBF concentrations peaked at 1 hr, and peak concentration (Cmax) was 1.760 µg/ml on day 1 and 1.817 µg/ml on day 5. Repeated dosing of MBF caused no significant change in PK parameters except area under curve (AUC) between day 1 (AUC0–∞D1 = 7.67 ± 0.719 µg × hr/ml) and day 5 (AUC0‐∞D5 = 8.70 ± 0.857 µg × hr/ml). A slight difference in mean residence time between 1st and 5th day of administration and accumulation index (AI = 1.13 ± 0.017) suggested lack of drug accumulation following repeated IM administration up to 5 days. Minimum inhibitory concentration (MIC) demonstrated that Escherichia coli (MIC = 0.04 µg/ml) and Pasturella multocida (MIC = 0.05 µg/ml) were highly sensitive to MBF. Time‐kill kinetics demonstrated rapid and concentration‐dependent activity of MBF against these pathogens. PK/PD integration of data for E. coli and P. multocida, using efficacy indices: Cmax/MIC and AUC0–24hr/MIC, suggested that IM administration of MBF at a dose of 2 mg kg?1 day?1 is appropriate to treat infections caused by E. coli. However, a dose of 5 mg kg?1 day?1 is recommended to treat pneumonia caused by P. multocida in goats. The study indicated that MBF can be used repeatedly at dosage of 2 mg/kg in goats without risk of drug accumulation up to 5 days. 相似文献
454.
455.
Harminder Pal Singh Ravinder Kumar Kohli Daizy Rani Batish Paramjit Singh Kaushal 《Journal of Forest Research》1999,4(3):245-254
The present paper reviews the available literature on the allelopathy of gymnosperms which constitute the famous boreal forests
known for their high quality timber and other products of great commercial importance. Nineteen genera belonging to six of
the seven taxonomic families of conifers comprising one of the most dominating and largest group of present day gymnosperms,
are reported to show the phenomena of allelopathy. The available information signifies the role these mighty trees play in
determining the understorey vegetation, ecological succession and forests dynamics besides causing regeneration problems to
the donor trees. The allelochemicals, identified from these plants, responsible for such interactions have also been summarised.
In most of the cases the leaching of phenolics from the litter predominantly of tree needles, which remain on the ground for
a longer time due to slow decomposition rate, are held responsible for these interactions. 相似文献
456.
Phani Kumar Pal Murugan Ashutosh Murkute SHashi Bala Singh 《The Journal of Horticultural Science and Biotechnology》2013,88(5):405-409
SummaryA current major concern is increasing levels of atmospheric CO2 which may be responsible for global warming or climate change. Fruit tree orchards have received attention in recent years by virtue of their potential to act as carbon pools. The trans-Himalayan valley (i.e., the Nubra Valley) at an altitude of 3,048 m, is covered by > 60,000 temperate fruit trees. The focus of this paper is on the potential of these fruit-yielding trees as a means of carbon sequestration in the Nubra Valley. The valley produces approx. 4,650 metric tonnes (MT) of apricot, apple, walnut, mulberry, grape, and plum fruit. It was observed that the total biomass of the temperate fruit trees (i.e., apricot, apple, and walnut) in the area surveyed was 40,000 MT dry weight (DW). Thus, 22,300 MT of carbon has been sequestered by these fruit species. This study revealed that the cultivation of temperate fruit crops species such as apricot, apple, and walnut could be exploited more efficiently for carbon sequestration which subsequently helps in mitigating global CO2 levels and restoring degraded land in these cold, arid areas by improving soil organic carbon (SOC) contents. These results concluded, in part, that growing biomass to sequester carbon is a beneficial grow-and-store process for sustainable development. 相似文献
457.
Niraj Singh Ashish K. Pal Baleshwar Meena R. K. Roy Sushma Tamta 《The Journal of Horticultural Science and Biotechnology》2017,92(6):577-582
Gladiolus is an economically important ornamental crop, cultivated for its beautiful flowers throughout the world. The correct genotype identification of plant material is very significant for the floriculture industry. The aim of this study was to develop sequence-characterised amplified region (SCAR) markers from RAPD and ISSR fragments for identification and authentication of Gladiolus germplasm. The SCAR markers developed could be easily employed as valuable tools to identify newly developed Gladiolus cultivars. The SCAR markers, viz. ScG12, ScG34, and ScG36, are specific to the DNA from all 62 Gladiolus cultivars, as they did not amplify the DNA of other taxa of the family Iridaceae, including Iris, Amaryllis, and Narcissus. All three SCAR markers distinguished Gladiolus from other taxa of the family Iridaceae, whereas marker ScAm was specific to the ‘Amethyst’ cultivar. Our results confirmed that this particular SCAR marker distinguished the ‘Amethyst’ cultivar from the other 62 Gladiolus cultivars investigated in the present study. This development of SCAR markers based on RAPD and ISSR markers seems to be the maiden attempt for Gladiolus cultivars. 相似文献