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Connectivity In Vehicular Network With Multi-Lane And Exponential Inter-Vehicle Spacing
No full textWireless connectivity is essential for vehicle ad hoc (VANET) communications and it is vital for safety applications. Previous work considered the connectivity of a linear finite network where cars are uniformly distributed in an infinite single dimension which is not realistic. In this paper the connectivity of vehicle network is calculated for single and multi-lane roads. The spaces between cars on the road are considered to follow the exponential distribution in a two dimensional topology. The probability of full connectivity and average network connectivity of VANET with single and multi-lane roads is analysed. For communication range R, car densities of 7cars/R or more were found sufficient to provide high connectivity within the city compared to 12cars/R for highways. Roads with several lanes show higher average connectivity but lower probability of full connectivity. We also investigated the effect of penetration rate on connectivity and found that while penetration rates of 50-100%, 10cars/R provide 80% probability of full connectivity, this reduces to 10% for 5-20% penetratio
Effect of First Irrigation Date on Sugarcane (Saccharum sp.) Ratoon Establishment
No full textA field experiment was conducted during 2010/2013 at Guneid sugarcane
research farm to evaluate the effects of the date of first irrigation on the growth of
sugarcane (Saccharum sp.) first ratoon. After harvest of main sugarcane crop, four first
irrigation dates (after 3, 9, 15 and 21 days) were applied and arranged in a completely
randomized block design with four replications. The plant growth attributes studied were
plant height, plant populations, stem diameter, biomass fresh and dry weights. First
irrigation date had significant effect on plant height, plant population, stem diameter and
insignificant effect on number of leaves/ plant and biomass fresh and dry weights. Plant
height, plant population and stem diameter were reduced with delayed first irrigation
date. Application of the first irrigation after 3 days from harvest was the best date for the
start of the ratoon growth
قياس تكامل أسواق السمسم السوداني وتنافسية صادراته
No full textيمثل السمسم أهم محاصيل الصادر السودانية إذ ساهم بأكثر من نصف مساهمة محاصيل الصادر الأخرى مجتمعة في أكثر من عام في الفترة 1993–2011م إلا أن صادراته شهدت تذبذباً في الكمية والعائد . هدفت هذه الدراسة إلى تحليل اقتصاديات إنتاج وتسويق وصادرات السمسم وتحديد مدى التكامل القائم بين أسعار السمسم في سوقي الأبيض والقضارف في المدى القصير والطويل ، وتحديد العلاقة السببية بينهما ثم قياس التنافسية والميزة النسبية الظاهرة لصادرات السمسم وتأثير السياسات الحكومية على ذلك . إعتمدت الدراسة على البيانات الثانوية المنشورة والمستخلصة من التقارير والإحصاءات الصادرة من المؤسسات الحكومية مثل وزارة الزراعة والغابات ، ووزارة المالية والاقتصاد الوطني ، وبنك السودان ، ووزارة التجارة الخارجية ومن منظمة الأغذية والزراعة التابعة للأمم المتحدة (FAO) ، والمنظمة العربية للتنمية الزراعية، وشركات الصادر . هذا بالإضافة للدوريات والأوراق العلمية والتقارير، والدراسات السابقة ذات الصلة بموضوع الدراسة. وقد شملت البيانات إنتاج وصادر وأسعار السمسم المحلية والعالمية وعائدات صادرته في الفترة من 1993م إلى 2011م . حللت البيانات بواسطة عدد من الطرق مثل التحليل الإحصائي الوصفي البسيط وتقنيات التكامل المشترك ومصفوفة تحليل السياسات ونموذج الميزة النسبية الظاهرة. أظهرت النتائج أن إنتاج وصادرات وعائدات السمسم شهدت تذبذباً كبيراً خلال فترة الدراسة وأن هنالك فارقاً كبيراً بين إنتاج السمسم وصادراته. كما توصلت الدراسة إلى وجود تكامل مشترك بين السلاسل الزمنية السعرية للسمسم في سوقي القضارف والأبيض ، وبالتالى وجود علاقة توازنية طويلة الأجل بينهما كما أنهما يرتبطان بعلاقة سببية عكسية . كما أظهرت الدراسة أن السودان يتمتع بميزة نسبية وقدرة تنافسية عالية في إنتاج وتصديرالسمسم. أوصت الدراسة بالعمل على إستقرار الإنتاج وزيادته بإتباع السياسات والإجراءات التى تؤدى لتحقيق هذا الهدف ، كذلك العمل على تطوير أسواق السمسم إدارياً وفنياً وإنشاء قاعدة بيانات شاملة لتسويق السمسم لاتاحة المعلومات التسويقية والسعرية لشركاء السوق وواضعي السياسات وصنّاع القرار والدخول في التجارة الإلكترونية
Chemical Contaminates of Meat and Meat Products which Threaten Human Health
No full textThe priorities, which concern meat and meat products consumption today, are food safety
issues and meat quality. Humans around the world are exposed to chemical contaminants
during their life time. Among the thousands of existing contaminates, some are persistent
and remain in the environment for years. The variation in measurable levels depends
mainly on the fact that some are synthesized as industrial products, whereas others are
released accidentally, as by-products, or given to animals as growth promoters or as
prophylactic or therapeutic agents. The measurement of these contaminants requires a
complex procedure including sample extraction, sample clean-up, and physico-chemical
analysis after chromatographic separation. Contaminants such as organochlorine
pesticides, heavy metals, microbes, melamine, hormones, antibiotic, and other feed
additives are often measured in various types of matrices during food safety programs,
environmental monitoring, and epidemiological studies. Serious health problems
including cancer, kidney diseases, disarray and other diseases in humans might be related
to food contaminates. According to the World Health Organization (WHO), 1.8 million
people died from diarrhea related diseases in 2005. Children and developing fetuses are
generally at greater risk from exposure to different chemicals. A great number of these
cases might be attributed to contaminate found on food. More than 90% of human
exposure to harmful materials is due to consumption of contaminated food items such as
meat, milk and dairy products, as well as fish and derived products. The overwhelming
majority of food poisoning in the world might originate from contaminated animal
products and there are millions of cases, and hundreds of deaths, caused by contaminated
animal products every year. This paper will discuss and highlight the most common
chemical and biological contaminates in meat and meat products from various species
which threaten human health
Isolation and Characterization of Three Casein Fractions from Camel Milk (Sudan)
No full textThis study was designed to isolate and characterize camel casein fractions using
biochemical methods. Whole camel casein was precipitated by acidification (pH 4.3) and
fractionated by ion exchange chromatography. Peaks corresponding to αs1-casein, β-
casein and κ-casein revealed molecular mass of 36.325, 31.732 and 25.044 kDa,
respectively, after SDS-PAGE. The three casein fractions were loaded on the same
isoelectric focusing (IEF) gel beside whole camel milk to identify bands corresponding to
each fraction. The αs1-casein was focused on the most acidic side of the gel followed by
β-casein on the middle of the gel, while κ-casein was the less acidic fraction. It could be
concluded that IEF technique could be effectively used for biochemical characterization
of camel casein on protein leve
إنتاج الإيثانول والآثار المتوقعة على إنتاج الأعلاف والمنتجات الحيوانية
No full textبدأ إنتاج الإيثناول بكميات تجارية فى البرازيل عام 1970 ثم تبعته الولايات المتحدة الأمريكية ومن ثم إنتشر إنتاجه فى كثير من بلدان العالم خلال العقدين الماضيين . هنالك أسباب ودوافع أدت إلى الإتجاه إلى الطاقة البديلة أهمها التغيرات المناخية العالمية التى نجمت عن ظاهرة الإحتباس الحرارى ولعله الجدير بالذكر أن تلك الظواهر تنعكس بصفة مباشرة أو غير مباشرة على أوضاع الإنتاج والإستهلاك للمنتجات لا سيما صناعة الأعلاف التى بدورها لها تأثير مباشر على إقتصاديات إنتاج اللحوم والألبان والدواجن . تناولت هذه الورقة أيضاً أوضاع الإنتاج الحيوانى بالسودان والدول العربية وأهمية إستغلال المواد العلفية المتاحة من أجل إنتاج أعلاف بتكلفة معقولة تمكن من زيادة الإنتاج فى مجالات الإنتاج الحيوانى مما لاشك فيه ان إنتاج الإيثانول من المولاس يقلل من فرص الإستفادة من المواد العلفية المتاحة التى يمكن إستغلالها للإنتاج خاصة وأن المولاس يعتبر مصدر رخيص للطاقة يمكن الإستفادة منه لتقليل الإعتماد على الحبوب لا سيما فى تغذية المجترات وكذلك الحد من تنافس الإنسان والحيوان للحصول على مصادر للطاقة . أيضاً أجرت الورقة مقارنة بين إقتصاديات إنتاج الإيثانول واللحوم وإتضح من خلال ذلك أن الجدوى الإقتصادية لإنتاج اللحوم تعتبر خياراً أفضل
A Novel and High Throughput Methods for Detection and Identification of Theileria equi and Babesia caballi
No full textTwo methods; namely, high-resolution melting (HRM) analysis and capillary
electrophoresis were used to detect and differentiate between Theileria equi and Babesia
caballi parasites that cause equine piroplasmosis worldwide. The HRM was evaluated
using control samples from the United States Department of Agriculture and field
samples collected from horses in Sudan and China. A region of the 18S rRNA gene, with
four known nucleotide differences between the two parasites, was selected for primer
design. HRM analysis successfully allowed detection and differentiation of T. equi and B.
caballi without the necessity of performing time-consuming and expensive post-PCR
procedures such as sequencing or restriction digestion. In another experiment, capillary
electrophoresis was used to detect and differentiate between T. equi and B. caballi, using
one set of primers designed to amplify the 18S rRNA gene in a single PCR. Capillary
electrophoresis method was found to be powerful in detecting mixed infections in
artificially mixed control samples. The results suggested that these two methods could be
ideal approaches for rapid genotyping, which is required to determine a drug of choice or
to administer an appropriate vaccine during an outbreak. The data obtained in this study
may contribute to the development of a national control strategy of EP in the Sudan
Assessment of Critical Control Point in Dairy Farms in Khartoum State, Sudan
No full textAn attempt was made to apply Hazard Analysis Critical Control Points (HACCP)
system in dairy farms in Khartoum State and to suggest control limits based on the
international standard. World Health Organization and Food and Agriculture
Organization recommended the HACCP system as a modern tool for disease prevention.
Critical points were investigated in 150 farms using California Mastitis Test and Rose
Bengal Plate Test for detection of bovine mastitis and brucellosis, respectively. The
results revealed that the overall prevalence rates of bovine mastitis and brucellosis were
69.3% and 36%, respectively. Other critical points were obtained from the owners of the
dairy farms by a questionnaire, using non-probability sampling method or willingness of
the owners for interview. Tick infestation was found in 94% of the farms which could be
a risk factor and the application of the odds ratio (OR) was 1.694. The use of antibiotics
for treatment of animals was, also, practiced in 54.7% of the farms. The critical points
associated with environment in dairy farms and distribution of milk in Khartoum State
was investigated, using a questionnaire survey and non probability sampling method. The
condition of beddings was poor in 70% of the dairy farms. Absence of cleaning and
disinfection of the teats were recorded in 108 and 104 farms, respectively. Furthermore,
distribution of the milk depended on either vehicle without chilling (50.7%) or donkey
carts (49.3%). Quantification of the risk indicated that hand washing of the milkers could
be a risk factor (OR = 2.574), while the condition of the housing as well as the
distribution of the milk could be a protective factor (OR=0.383 and 0.278, respectively).
In conclusion, many critical points associated with animals or environment were
observed in dairy farms in Khartoum State. Diseases of animals included infectious and
zoonotic disease, flies and tick infestation, use of antibiotics for treatment and absence of
veterinary care. The critical points associated with environment were poor hygiene during
handling, storage and distribution of the milk. Moreover, the control limits for all
mentioned critical points were as follow: Access to veterinary service, vectors control,
improvement of general hygiene in the dairy farms during different practices taking in
consideration the low temperature during storage and distribution of the milk
Development of Vaccines in Poultry Industry–Malaysian Experiences
No full textMalaysia, due to its rapid growth and structured changes, has transformed into a
prosperous, urban and industrialized economy since early '70s. Less than 5% households
are considered poor compared to 50% in 1957, when the country achieved its
independence. However, there are still substantial spatial individuals living in poverty,
especially in rural areas. One of the sectors under food security in Malaysia, for protein
sustainability, is increasing the amount of animal protein, so that they are readily accessible
to the rural poor. Chicken meat has been identified as the cheapest source of animal
protein. Poultry industry in Malaysia, largely propelled by the private sector, has
significant contribution in supplying the protein needs of the population as reflected by
the higher percentage share of the sector in the total livestock value. The annual
production of eggs and meat are valued between RM 1.78 billion and RM 6.03 billion.
Besides being a cheap source of protein, chicken has a special status due to its general
acceptance among the Malaysian multi-racial and multi-ethnic population, since there is
no religious restrictions associated with it. The rapid growth of the poultry industry is
primarily due to the advances in poultry management, nutrition, genetics and better disease
diagnosis and control. However, infectious diseases are still the major causes of losses in
poultry industry and farmers depend mainly on imported vaccines, which are costly and
sometimes may not be very effective. The need to provide constant source of cheap animal
protein to the rural poor led our team to be involved in food security initiatives via
disease control, by embarking on poultry vaccines development, targeting the control of
diseases in village chickens, as well as commercial chickens. We focus on enhancing the
health of poultry especially village chickens, for more than 20 years, by developing
efficacious vaccines which are cheaper than the imported vaccines. One of the vaccines is
for Newcastle disease, which is a very important disease in poultry, worldwide. The
success of this vaccine, has led to an increase in number of village chickens being reared
by rural farmers. Some farmers now rear large number of village chickens semiintensively.
The development of this vaccine has also led to the establishment of the first
and the only animal vaccine manufacturing company in the country, and it is now
certified with Good Manufacturing Practice (GMP). Our research group has developed
two other vaccines which are now sold in more than 8 countries. This paper highlights the
stages of vaccine developments, from research, development, laboratory and field trials,
up scaling and commercialization
Medicinal Plants in Sudan: Role in Animal and Human Health, Productivity and Poverty Alleviation
No full textSudan has a wide diversity climate which is responsible for its varied vegetation
and very rich flora. Currently, according to the World Health Organization, about 80% of
the world population depends on traditional medicine for primary health care. In Sudan as
well as elsewhere, people prefer to use traditional medicine rather than synthetic drugs,
because herbs can easily be obtained from nature and are cheap and have less side
effects. This review paper aims at presenting data on the therapeutic activity of some
medicinal plants used in Sudanese traditional medicine for animal and human diseases
with emphasis on published data in Sudan in addition to research conducted by graduate
students at the University of Khartoum. The review, also, highlights the toxicity of some
plants that limited their use despite useful active ingredients. The review includes data on
plants with antimicrobial, antiparasitic, hepatoprotective, hypoglycemic and antioxidant
activities, and many have direct impact on animal welfare, food security and increase in
national econom