Soil and water conservation in ethiopia

The article shows results of an international and interdisciplinary project with the title ‘Rainfall and its Erosivity in Ethiopia’. The article contains information about the traditional soil conservation practices, the reasons for intervention with traditional soil conservation technologies, the historical background of instutionalized soil conservation activities, the institutional frame work for soil conservation activities and their achievements, and the different departments and organisations for soil and water conservation as far as soil erosion in Ethiopia is concerned. As a conclusion and recommendation, the major constraints of the past activities and the current situation including future trends were discussed.     

Effects of lead nitrate on the activity of metabolic enzymes during early developmental stages of the African catfish, <Emphasis Type="Italic">Clarias gariepinus</Emphasis> (Burchell, 1822)

Glucose-6-phosphate dehydrogenase (G6PDH), lactate dehydrogenase (LDH) and pyruvate kinase (PK) are key metabolic enzymes. G6PDH has been used as a biomarker of pollution-induced carcinogenesis in fish. LDH has been used as marker of lesions in toxicology and clinical chemistry, and PK catalyses the conversion of phosphoenol pyruvate to pyruvate, with regeneration of ATP. The effect of different concentrations of lead nitrate on the activity of these enzymes in two different early ontogenetic stages (embryonic and free embryonic stage) of the African catfish Clarias gariepinus was investigated. Embryo homogenates were used for measurements of G6PDH, LDH and PK activity spectrophotometrically at 340 nm and 25°C. The ontogenetic variations of the three enzymes during early ontogeny, from the 30 h to the 168 h post-fertilisation stage (PFS) (beginning of exogenous feeding), were studied. There was a significant decrease in activities of all three enzymes from 30 h-PFS to 96 h-PFS, followed by a significant increase in G6PDH and LDH. PK showed insignificant fluctuations in activity. Different patterns of enzyme activities were recorded due to exposure to different lead nitrate concentrations (100 μg/l, 300 μg/l and 500 μg/l). In the pre-hatching stage (30 h-PFS) the activity of the three enzymes increased at exposure to 100 μg/l lead nitrate and then decreased with increasing dose. In the post-hatching stages (48 h-PFS–168 h-PFS) G6PDH activity increased and LDH activity decreased with increasing lead concentrations. Unlike G6PDH and LDH, the PK enzyme fluctuated during the post-hatching stages and did not reveal a specific trend of response (increase or decrease) with increasing lead concentrations. Therefore, the measurement of G6PDH and LDH activities, but not PK activity, could be useful biomarkers of intoxication to reveal the embryotoxic potential of lead nitrate in fish embryos. The post-hatching stages of the African catfish are more sensitive than the pre-hatching stage (30 h-PFS) is, probably due to the protective capacity provided by the hardened chorion. The interaction and the main effects of age and lead doses were found to be highly significant, referring to the great impact of lead on these enzyme systems with increasing early development.     

Corpuscular oxidation in newborn crossbred calves naturally infected with Theileria annulata

Erythrocytic lipid peroxidation has been implicated as a cause of anemia in Theileria annulata infection in cattle. The present study aimed to evaluate oxidative damage of membrane lipids and proteins in addition to hemoglobin (Hb) as three criterions of erythrocyte oxidation and their relation to erythrocyte deformability and anemia of newborn crossbred calves (Friesian × Egyptian Balady breed) naturally infected with T. annulata. Twenty-five T. annulata-infected calves (aged 20-30 days) along with 15 age matched healthy controls were used. Percentage of parasitemia varied from 12% to 63% (34.76 ± 3.05%). In comparison to controls, infected calves showed increased levels (P<0.001) of lipid peroxidation (malondialdehyde; MDA, 52%) and protein oxidation (protein carbonyls; PCs, 132%) in erythrocyte membrane as well as increased values of Hb oxidation (methemoglobin; MetHb, 186%), corpuscular osmotic fragility (15.1%) and hemolysis (free Hb; 195.5%). Parasitemia was positively correlated with MDA (r=0.41, P=0.039), PCs (r=0.45, P=0.023) and MetHb (r=0.40, P=0.042). Also, percent of erythrocytic deformability (echinocytosis) was positively correlated with MDA (r=0.49, P=0.013) and PCs (r=0.63, P<0.001). On the other hand, erythrocytic packed cell volume was negatively correlated with MDA (r=-0.44, P=0.028), PCs (r=-0.72, P<0.001) and MetHb (r=-0.42, P=0.037). In conclusion, T. annulata infection is associated with a parasitic burden-dependant oxidative damage to the erythrocyte membrane protein and lipid contents in addition to Hb. This oxidative damage is linked to the morphological changes of the erythrocyte and may act as mechanisms contribute to pathogenesis of anemia in T. annulata infection in newborn calves.     

An outbreak of suspected tick paralysis in one-humped camels (Camelus dromedarius) in the Sudan

An outbreak of suspected tick paralysis occurred in one-humped camels in Southern Darfur, the Sudan, between latitudes 11-12 degrees N and longitudes 24-25 degrees E, when the camels were herded in tick infested areas. It involved 251 camels of different ages, in ten herds causing 34.3% mortality. The symptoms were incoordination of movements, unsteady gait and recumbency followed by death or recovery. Hyalomma adults and/or Rhipicephalus nymphs and adults were incriminated to be the cause of the disease. Transient paralysis in a guinea pig was produced after experimental feeding of ticks. Removal of the camels from the tick infested areas and treatment against the ectoparasites with Lindane at the concentration of 0.23% contributed to controlling the disease.     

Phosphate sorption in some representative soils of Bangladesh

An experiment was conducted to observe the phosphate sorption potential of some soils of Bangladesh. Three soil series of calcareous origin, namely Sara (Aquic Eutrochrept), Gopalpur (Aquic Eutrochrept) and Ishurdi (Aeric Haplaquept), and two soil series of non-calcareous origin, namely Tejgaon (Rhodic Paleustult) and Ghatail (Aeric Haplaquept), were selected. The soils were equilibrated with dilute solution of calcium chloride containing graded concentrations of phosphate (0, 1, 2, 5, 10, 25 and 50?μg?P?mL^?1), and the amount of phosphate sorbed or desorbed was determined. Although all the soils showed potential for sorbing phosphate from applied phosphorus, their ability to sorb phosphorus differed. Increasing rates of phosphate application increased the amount of P sorption but reduced phosphate sorption percentage in all soils except Tejgaon. Phosphate was sorbed by the soils in the order: Tejgaon > Ghatail > Ishurdi > Gopalpur > Sara at 50?μg?P?mL^?1 application. Soils possessing higher amounts of free iron oxide and clay sorbed more phosphate from applied phosphorus.     

Protecting potato plants against PVX and PVY viral infections by the application of native and chemically modified legume proteins

Journal of Plant Diseases and Protection - Methylated soy and chickpea proteins (MSP and MCP, respectively), and 11S globulin (a soy protein fraction), are characterized by net positive charges and...     

轮台小白杏丰产栽培配套技术探讨1）

轮台属于大陆型气候,气候干燥,昼夜温差大,很适宜杏树的种植。但是该县杏树生产目前还是传统的粗放经营方式,产量低,品质差,效益低,严重影响其发展进程。因此,只有因地制宜的建立杏树生产基地,在进行集约化的土水肥管理和树体管理措施才能更好地适应市场需求,生产产量和品质较高的,适应国内外市场的优质商品果。在轮台小白杏的生物学特性,生长地环境进一步调查了解的基础上,对小白杏生产过程中采取的主要技术措施进行了分析和总结,结合小白杏的产量和品质,提出了比较适宜的高产并优质果生产的栽培管理的配套技术措施。认为在小白杏生产过程中只要采取规范化并集约化的栽培管理措施,可以提高产量和品质,达到提高经济效益的栽培目的。     

Growth performance,haematological and serum biochemical profiles in rainbow trout (Oncorhynchus mykiss) fed diets with varying levels of lupin (Lupinus albus) meal

A feeding experiment was conducted to study the response of rainbow trout juveniles fed different levels of lupin meal in diets for rainbow trout juveniles. Very limited information is available on the relationship between dietary lupin meal in rainbow trout health status. Therefore, this study aimed to determine the effects of lupin meal inclusion levels (0%, 15%, 30%, 45%, and 60%) on growth performance and health status of rainbow trout juveniles. The experimental diets (LM₀, LM₁₅, LM₃₀, LM₄₅, and LM₆₀) were formulated iso‐nitrogenous (41% crude protein) and iso‐calorific (18% crude lipid). The fish were fed twice a day. As a result, the best growth performance was observed in fish fed with LM₁₅ and LM₃₀ diets. No significant differences were detected among experimental groups in terms of body compositions. The haematological values showed significantly (p < 0.05) lower heamatocrit and mean cellular volume (MCV) in the group of LM₆₀ compared with the other groups. For the other haematological parameters such as haemoglobin, red blood cell and mean cellular haemoglobin studied in the present study no significant differences were observed (p < 0.05). The lupin meal included groups showed significant reduction in total protein (TPROT), triglyceride (TROG), cholesterol (CHOL), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) compared with the control group (p < 0.05). The inclusion of lupin meal did not cause any changes in glucose (GLU), glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) between the treatment groups (p < 0.05). In conclusion, lupin meal might be used in rainbow trout diets up to 30% without any malnutrition effect on growth performance, haemotological and serum biochemical parameters.     

Effect of weight and apllied force on the friction coefficient of the spunlace nonwoven fabrics

Friction force that can be defined as the forces resisting relative to the movement between two surfaces contacting with each other plays an important role in textile industry. During usage, the fabrics continue to friction to the textile or the other surfaces and because of this problem fabric surface structure deteriorates. Therefore, most of the scientists have been designed different methods in order to estimate surface properties and friction of fabric before their usage. In this study, friction experiments have been performed by designed and manufactured two different systems which work as a horizontal platform and inclined plane. It has tried to investigate friction properties of polyester nonwoven fabric samples which are produced by spunlace methods (air laid and spunlace bonding) with different weights. While the selected fabric samples weight increase, it has been seen that a low friction force occurred because of more stable structure. And also, it has been observed that the higher vertical force (load) applied on the specimens the lower the coefficient of friction. These results shows that both measurement methods have similar tendencies based on the analyzed results.