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71.
The ethanolic extract of leaves of Nymphaea stellata given by oral route to diabetic rats at dose of 100 and 200 mg/kg/day for seven days reduced significantly by 31.6 and 42.6 % the plasma glucose level increased by intraperitoneal injection of 120 mg/day of alloxan. Moreover, the treatment significantly affected the plasma level of cholesterol and triglyceride.  相似文献   
72.
1. The aim of the experiment was to investigate the effect of gaseous stunning methods on the carcase and meat quality of broilers (dead weight 1.0 to 2.3 kg) in comparison with electrical stunning.

2. Two replicates of broilers (age 54 and 59 d respectively) were stunned in carbon dioxide, in argon or by electric current, and the carcases were plucked either by a mechanical plucker or by hand.

3. Carcase and meat quality were evaluated to determine the effect of these stunning treatments and plucking methods. The quality factors measured included pH at 20 min post‐mortem, ultimate pH, texture and colour of the pectoralis major muscle, and the incidence of carcase appearance defects, cooking loss, broken bones and bruises in the breast and leg muscles.

4. Stunning method had a significant effect on pH at 20 min, ultimate pH, texture and colour of breast meat. Plucking method had a significant effect on the cooking loss and texture.

5. Argon stunning resulted in fewer muscle haemorrhages, a more rapid early post‐mortem fall in pH and more tender breast meat than in the electrically stunned broilers; carbon dioxide stunned broilers had intermediate values for pH decline and meat tenderness but were not significantly different from argon stunning regarding muscle haemorrhages.

6. Appearance defects occurred to a similar extent in all the stunning methods and mechanical plucking resulted in 4 times as many defects compared with hand plucking; the incidence of broken bones was higher in mechanically plucked broilers than in hand plucked carcases.

7. Gaseous stunning of broilers produced relatively better quality carcases and meat than electrical stunning, and therefore may have commercial advantages.  相似文献   

73.
1. Eighty broilers were stunned with anoxia (< 2% oxygen) induced by argon and after evisceration, at 20 min post‐mortem, the carcases were chilled in slushed ice for 30 min. Twenty breasts were filleted at each time 1, 2, 3 and 24 h post‐mortem and aged overnight at 1°C.

2. An additional 40 broilers were stunned either by anoxia or by constant current electrical stunning (107 mA 50Hz) and their eviscerated carcases held overnight at 1°C prior to filleting at 24 h postmortem.

3. All the breast muscles (pectoralis major) were cooked at 24 h postmortem and their texture measured. The results indicated that the mean texture of breasts from the different stunning and filleting time treatments were similar, and there were no significant differences between them.

4. It is concluded that stunning with anoxia followed by a rapid chilling would enable the broiler carcases to be filleted at 1 h postmortem with no adverse effect on the texture of the meat.  相似文献   

74.
The results of a field trial conducted at the Livestock Research Station, Thiruvazhamkunnu, Kerala to study the compatibility of different components in a silvo-pastoral system revealed that growth and yield of fodder species were significantly influenced by the tree components only after tree canopy formation. The fodder species such as Pennisetum purpureum Schum., Panicum maximum Jacq., Brachiaria ruziziensis Griseb. and Euchlaena mexicana Schrad. grown in association with Casuarina equisetifolia J. R. & G. Forst. and Ailanthus malabarica DC recorded comparatively higher forage yield even after canopy formation. However, forage crops grown in combination with Acacia auriculiformis A. Cunn. ex Benth. and Leucaena leucocephala (Lam.) de Wit. registered relatively lower values for growth and yield. Increased light infiltration into the understorey due to the cladophyllous canopy can be attributed as reason for the higher fodder productivity under Casuarina. Due to the combination of crown size and shape, tree height and spacing the amount of light intercepted by Ailanthus also was very low. Among the four multi-purpose trees used, Acacia recorded the maximum growth rate followed by Casuarina, Ailanthus and Leucaena. Forage productivity of the four species was in the order: Pennisetum purpureum > Panicum maximum > Brachiaria ruziziensis > Euchlaena mexicana. Casuarina with Pennisetum/ Panicm were found to be optimal tree — forage combinations for silvo-pastoral systems.  相似文献   
75.
A split plot trial involving Ailanthus triphysa (ailanthus) at four spacings (3 m×1 m, 2 m×2 m, 3 m×2 m and 3 m×3 m) and four fertiliser regimes (0:0:0, 50:25:25, 100:50:50 and 150:75:75 kg ha−1 per year N, P2O5, K2O) was initiated in June 1991. Objectives included evaluating the growth and yield potential of ailanthus grown under differing density and fertiliser regimes and to estimate the nutrient export through harvest. Ninety-six randomly selected average-sized trees were felled at 8.8 years of age for assessment. Results show that height, diameter, stand leaf area index, biomass production and volume yield were greater in the 2 m×2 m spacing. Repeated application of fertilisers at 1.2, 2.25 and 5.25 years after planting had little effect on biomass and volume yields, presumably because of weed competition (despite periodic weed control), higher pest incidence (in the heavily fertilised plots) and/or moderately adequate soil nutrient levels. Regarding partitioning of tree biomass, stem wood represented the principal component (>70%), while foliage contributed the least (<7%). Conversely, foliar N, P and K concentrations were the highest, followed by branch wood, coarse roots and stem wood. Denser stands showed greater accumulation of N, P and K with higher potential for nutrient export through harvest. However, as the bole fraction accounted for only about 56–64% of the total nutrients removed, leaving other biomass components (foliage and branches) at the site will reduce the associated nutrient export. Wider spacings (3 m×2 m and 3 m×3 m) were more efficient in N and K use, but P use efficiency was higher in 2 m×2 m. Likewise, trees in the no fertiliser plots exhibited greatest N, P and K use efficiencies. Available soil P, K and organic C levels declined with increasing tree density, while repeated fertilisation increased nutrient concentrations. Soil pH and available P levels declined in comparison to the pre-treatment values.  相似文献   
76.
Indiscriminate use of natural resources in the past has lead to fuelwood shortages in many parts of the tropical world. To surmount this domestic energy crisis, not only degraded sites must be planted with trees having high fuel value potential, but also agroforestry promoted on arable lands. To enable choice of species for such energy plantations/agroforests in the humid tropics of peninsular India, we assessed the heat of combustion and physical properties that determine combustion of phytofuels, such as ash content, specific gravity and moisture content. Bark and wood samples of 45 multipurpose tree species in the homegardens of Kerala, India and three fuel materials of local importance (coconut [Cocos nucifera] endocarp, dried coconut spathe and dehiscent rubber [Hevea braziliensis] pericarp) were evaluated. Variations abound in the calorific values and physical properties of species and tissue-types. In general, heat of combustion and specific gravity followed the sequence: heartwood > sapwood > bark, while mean ash percentage followed a reverse order (bark > sapwood > heartwood). Ash content had a negative correlation with heat of combustion, but specific gravity exerted a positive influence. Furthermore, ash content and wood specific gravity were inversely related. Although green moisture content increased in the order: bark < heartwood < sapwood, it failed to show any predictable relationship with heat of combustion.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
77.
Organogenesis and terpenoid synthesis in Mentha arvensis   总被引:1,自引:0,他引:1  
Phatak SV  Heble MR 《Fitoterapia》2002,73(1):32-39
Leaf discs obtained from field grown plants of Mentha arvensis were used to initiate multiple shoots on Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurine (5 mg l(-1)) and naphthaleneacetic acid (0.5 mg l(-1)). Profuse rooting was achieved when the well-grown shoots were cultured on half strength MS medium supplemented with indole-3-acetic acid (2 mg l(-1)). The regenerated plantlets were hardened and successfully transferred to soil and grown to maturity. Tissues at different stages of differentiation were analyzed for their essential oil content and characteristic monoterpene pattern. Tissue culture raised plants show the same essential oil profile as that of the parent plant. However, tissues at early stages of growth show distinct changes in oil composition, such as high levels of pulegone in shoot cultures.  相似文献   
78.
Leptospirosis is an exacerbating factor responsible for the drastic decline of sloth bear population in India. In this study, a multipronged approach based on antigen detection using Polymerase Chain Reaction (PCR) employing G1/G2 and LigBF/LigBR primers, antibody detection using Microscopic Agglutination Test (MAT) and recombinant LigBCon1-5 antigen based Latex Agglutination Test (rLigBCon1-5 LAT), serum biochemistry using hepatic (serum glutamate oxalo acetic transaminase (SGOT) and serum glutamate pyruvic transaminase (SGPT) and renal biomarkers (blood urea nitrogen (BUN) and Creatinine) and gross/histopathological evidence in liver and kidneys were employed to investigate leptospirosis in captive sloth bears. A total of 133 serum samples collected from Agra (n=113) and Bannerghatta (n=20) sloth bear rescue centers were screened using MAT and rLigBCon1-5 LAT. A total of 87 and 78 sera tested positive by MAT and LAT respectively. Pyrogenes was the leading serovar obtained using MAT followed by Icterohaemorrhagiae, Javanica, Grippotyphosa, Canicola and Tarassovi. The relative sensitivity, specificity and accuracy of rLigBCon1-5 LAT in comparison to MAT were 89.66%, 100% and 93.23% respectively. PCR performed on hepatic and renal tissues showed amplicon of 285 and 219 base pairs for G1/G2 and LigBF/LigBR primers respectively. Gross evidence (icteric liver, severely engorged hepatic sinusoids, congested kidneys with necrotic white spots on sub capsular surface), histopathology (severe hepatic degeneration and tubulointerstitial nephritis) and elevated hepatic/renal biomarkers were suggestive of leptospirosis. This study suggests that rLigBCon1-5 LAT can be employed as a pen-side test for detecting leptospirosis in sloth bears.  相似文献   
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