Patterns of root respiration rates and morphological traits in 13 tree species in a tropical forest

The root systems of forest trees are composed of different diameters and heterogeneous physiological traits. However, the pattern of root respiration rates from finer and coarser roots across various tropical species remains unknown. To clarify how respiration is related to the morphological traits of roots, we evaluated specific root respiration and its relationships to mean root diameter (D) of various diameter and root tissue density (RTD; root mass per unit root volume; gcm(-3)) and specific root length (SRL; root length per unit root mass; mg(-1)) of the fine roots among and within 14 trees of 13 species from a primary tropical rainforest in the Pasoh Forest Reserve in Peninsular Malaysia. Coarse root (2-269mm) respiration rates increased with decreasing D, resulting in significant relationships between root respiration and diameter across species. A model based on a radial gradient of respiration rates of coarse roots simulated the exponential decrease in respiration with diameter. The respiration rate of fine roots (<2mm) was much higher and more variable than those of larger diameter roots. For fine roots, the mean respiration rates for each species increased with decreasing D. The respiration rates of fine roots declined markedly with increasing RTD and increased with increasing SRL, which explained a significant portion of the variation in the respiration among the 14 trees from 13 species examined. Our results indicate that coarse root respiration in tree species follows a basic relationship with D across species and that most of the variation in fine root respiration among species is explained by D, RTD and SRL. We found that the relationship between root respiration and morphological traits provides a quantitative basis for separating fine roots from coarse roots and that the pattern holds across different species.     

Ovine anti-rabies antibody production and evaluation

In view of the disadvantages of human and equine rabies immunoglobulin still there is urgent needs for safe and cost-control anti-rabies immunoglobulins especially for person who have been severely exposed (categories III) to the virus. Our attempt to produce a less immunogenic and cheaper anti-rabies immunoglobulin affordable for those people living in developing countries, has been harnessed the ovine as a bioreactor instead the horse. The animals have been intramuscular immunized, and the plasma processed with 5% caprylic acid to yield IgG with purity of 95%. Moreover, antibody apparently indicated that the titer and neutralizing indexes were harmonized, especially at higher antibody dilution. The results showed that three immunized sheep were produced about 7000 IU of purified anti-rabies antibody. Sheep's IgG has low immunogenic effect than human and horse antibodies when injected into the mouse. Pure concentrated ovine antibody may serve as a possible alternative to currently available anti-rabies human or equine immunoglobulin.     

Superoxide dismutase activity as a measure of hepatic oxidative stress in cattle following ethionine administration

The goal of this study was to assess if oxidative stress, as measured by alterations in the concentrations of antioxidant enzymes in the liver and erythrocytes of cattle, could be induced following dl-ethionine administration. Whole blood, serum and liver biopsy samples were collected 0, 4, 7 and 10 days after intra-peritoneal ethionine administration to five cows. The activities of the antioxidant enzymes copper zinc superoxide dismutase (Cu, Zn SOD) and catalase were assessed in the liver biopsies which were also examined histopathologically.Significant increases in hepatic Cu, Zn SOD concentrations (P < 0.01) were noted on days 7 and 10 post-treatment. Hepatic catalase activity decreased significantly (P < 0.01) on days 4, 7 and 10 post-treatment and erythrocyte Cu, Zn SOD activity was significantly increased on day 10. Serum biochemical analysis revealed a significant increase (P < 0.01) in non-esterified fatty acid concentrations on day 4 and significant decreases in total cholesterol and phospholipid levels on days 4 (P < 0.05), 7 (P < 0.01) and 10 (P < 0.01). In this model system, dl-ethionine administration was effective in inducing oxidative stress particularly reflected in the liver.     

Effect of genotype, environment and time of harvest on sugarcane yields at middle and upper Egypt

[目的]了解在埃及两个不同地区种植的4个有潜力甘蔗品种的最佳收获期.[方法]于2009～2010、2010～2011年度分别在埃及卢克索省El-Mattana研究站(上埃及)和米尼亚省Mallawi研究站(中埃及)进行了两个田间试验,采用裂区设计,3个重复,对4个有潜力的甘蔗品种G95-21、G98-28、G99-160和G99-103的新植蔗分别在不同时间,即(植后)10、11、12和13个月收获,并分别调查农艺性状、甘蔗产量和糖产量.[结果]在(植后)13个月收获时,甘蔗品种G99-103和G95-21的茎高、茎径、茎重、蔗糖分、蔗汁纯度、出糖率、蔗产量以及糖产量最高,且以在卢克索省种植的甘蔗大部分农艺性状表现更优.品种、收获期和种植地点的第一和第二交互顺序显著影响所有甘蔗的农艺性状.[结论]在埃及中上部地区种植甘蔗品种G99-103和G95-2,且在12和13个月株龄时收获,可以获得最高的蔗茎产量和糖产量.     

Effect of different dietary concentrations of inorganic and organic copper on growth performance and lipid metabolism of White Pekin male ducks

1. The effect of different dietary concentrations of inorganic and organic copper on performance and lipid metabolism of White Pekin ducks (WPD) was investigated from 1-49 d of age. A common basal diet was supplemented with 4, 8, 12 and 150?mg/kg of copper (Cu) from inorganic and organic sources to obtain 9 treatments, including 4 concentrations of Cu x two sources, and the unsupplemented control group. Each treatment contained 5 replicates of 9 male ducks each.

2. Supplementation of Cu at 8?mg/kg in inorganic form was adequate for growth of male WPD from 1-56 d of age. Inorganic Cu significantly decreased feed intake and improved feed conversion ratio, compared with the organic form.

3. Plasma Cu significantly increased, while plasma Zn significantly decreased, due to Cu supplementation. Organic Cu showed better efficacy than inorganic for improving liver Cu concentration, Cu excretion and apparent Cu retention.

4. Dietary Cu concentration significantly affected percentage blood and Hgb and abdominal fat deposition. In addition, inorganic Cu increased percentage blood and abdominal fat deposition compared with the organic source.

5. Supplementation of 150?mg/kg of Cu significantly decreased liver and meat lipids, cholesterol, and colour and tenderness of meat; while liver protein and moisture was increased. In addition, dietary 150?mg/kg of Cu supplementation significantly decreased plasma lipids, triglycerides and cholesterol, while increasing plasma AST and ALT.

6. Organic Cu was more potent for decreasing plasma triglycerides than the inorganic source. However, plasma cholesterol was only significantly decreased with the inorganic source of Cu, compared with the unsupplemented control.

7. The organic Cu was safer as a feed additive for WPD, especially at the lower concentrations up to 12?mg; while some mild to moderate changes may be developed at the higher doses, when fed at pharmacological concentrations as a growth promoter.     

Pharmacokinetics of difloxacin in goats

The pharmacokinetic properties of difloxacin following intravenous (i.v.) and intramuscular (i.m.) administration in goats were investigated. Difloxacin was administered in a single dose of 5 mg/kg body weight for both routes and was assayed in biological fluids (serum and urine) to determine its concentrations, kinetic behaviour and systemic availability. Following a single i.v. injection, the serum difloxacin level was best approximated to follow a two-compartment open model using weighted non-linear regression analysis. The elimination half-life (t1/2 beta) was 6.3 +/- 0.11 h. The volume of distribution at steady-state (Vdss) was 1.1 +/- 0.012 L/kg and the total body clearance (Cltot) was 0.13 +/- 0.001 L/kg/h. Following a single i.m. administration, difloxacin was rapidly absorbed and the mean peak serum concentration (4.1 +/- 0.23 micrograms/ml) was achieved 1 h post administration. The extent of serum protein binding of difloxacin in goats was 13.79 +/- 1.02% and the systemic availability was 95.4 +/- 1.17%. Following i.m. injection of difloxacin at a dose rate of 5 mg/kg b.wt for 5 consecutive days, the drug could not be detected in serum and urine at 4th day from the last injection.     

Impact of two synthetic pyrethroids and methomyl on management of the cabbage aphid,brevicoryne brassicae (L.) and its associated parasitoid,diaeretiella rapae (M'Intosh)

The effectiveness of two synthetic pyrethroids, cypermethrin and fenvalerate, and of methomyl applied to cabbage plants was tested against the cabbage aphid, Brevicoryne brassicae (L.), and its parasitoid, Diaeretiella rapae (M'Intosh). Dosage rates chosen were equivalent to the manufacturer's maximum and minimum recommendations. Methomyl was considerably more toxic to B. brassicae adults than the two synthetic pyrethroids used. Fenvalerate, at the lowest rate used (71 g ha^?1), showed satisfactory effectiveness in reducing aphid adult population on treated plants by c. 77% below that of the control. All insecticides and rates used significantly reduced the emergence of parasitoid adult D. rapae from mummified aphids compared to the control. Fenvalerate clearly had less impact on emergence than cypermethrin or methomyl at any dosage used, while methomyl has appeared to be the most toxic compound in this respect. Longevity of parasitoid adults was highly affected by insecticide application, particularly those adults emerging from mummified aphids exposed to methomyl or cypermethrin. However, only a slight difference in longevity was seen at the lower rate of 71 g ha^?1 of fenvalerate. At the lowest dosage rates used, methomyl and cypermethrin reduced the F₁-progeny of adult parasitoid females by 70.5% and 58.3%, respectively, of the control, whereas fenvalerate reduced the progeny by only 36.4%.     

Total glutathione and glutathione reductase in bovine erythrocytes and liver biopsy

The goal of the present study was to measure the total glutathione level and glutathione reductase activity in bovine erythrocytes and liver biopsy. Five cows were injected intraperitoneally with DL-ethionine (12.5 mg/kg B.W.), and two control cows were injected with normal saline (0.9% NaCl). Ultrasonography guided liver biopsy, and blood samples were collected at 0, 4, 7 and 10 days after injection. The hepatic total glutathione level was significantly increased on Days 7 (p<0.05) and 10 (p<0.01), and hepatic glutathione reductase activity was significantly increased on Days 4 (p<0.05), 7 (p<0.01) and 10 (p<0.01). There were insignificant changes in the erythrocytic total glutathione level. The present study demonstrated that liver biopsy is a valuable tool for detecting oxidative stress and for diagnosing hepatic dysfunction in cattle from the viewpoint of the status of glutathione and glutathione reductase.     

The effects of short-term recombinant bovine somatotropin treatment on fattening performance,carcass composition and visceral organ weights in karayaka lambs in Turkey

Recombinant bovine somatotropin (bST) was administered s.c. to lambs for 6 weeks to evaluate its effects on fattening performance, carcass composition and visceral organ weights. Twenty male Karayaka lambs were injected with 250 mg bST every two weeks. Body weight, live weight gain, feed intake and feed conversion rate were not affected by treatment. Head, feet, skin, liver, spleen, kidneys, filled and empty gastrointestinal tract, penis, testis, pelvic fat and internal fat weights were similar for the two groups. Lung weight increased by 17.4% (P < 0.01) and weight of heart decreased 22.7% (P < 0.05) in bST treated lambs. The only carcass characteristics that were affected by bST administration were limb muscle which increased from 1331 g to 1417 g (P < 0.05), loin fat which decreased from 275 g to 174 g (P < 0.01), shoulder fat which decreased from 26 g to 13 g (P < 0.01) and total fat/final weight percentage which decreased from 9.8% to 7.6% (P < 0.05). The results of this study show that prolonged release formulation of bST treatment reduces fat tissue, but does not significantly affect fattening performance or weights of visceral organs, muscle and bone.     

Natural bee-honey based biostimulants confer salt tolerance in onion via modulation of the antioxidant defence system

Plant biostimulants are an emerging trend of crop management products which can enhance nutrient uptake, plant growth and productivity under various abiotic stresses. The ability of diluted bee-honey extract (DHE) to enhance the tolerance of onion plants to salinity stress has been investigated. Two-season field experiments were consecutively conducted in 2015/16 and 2016/17 to study the effect of 25–50 g/L DHE foliar application on growth, yield, physio-biochemical attributes, and antioxidative defence of two onion cultivars (i.e. Giza^Red and Giza-20) grown on a saline soil (EC = 8.81 dS m^?1). Results exhibited that DHE significantly increased biomass production, bulb yield and water use efficiency, leaf photosynthetic and pigments contents. Additionally, DHE applicati\on also improves osmoprotectants, membrane stability index (MSI) and relative water content (RWC), and enzymatic and non-enzymatic antioxidants of both onion cultivars in comparison with untreated control plants. In general, both cultivars showed a similar response to the DHE. Results of this study highlighted the potential impact of DHE as a promising plant bio-stimulant for overcoming the harmful effects of soil salinity stress by increasing the activity of plant antioxidative defence systems