Nutrient requirements of beef cattle

Keywords: Mecanique des sols ; Drainage ; Ecoulement souterrain Reference Record created on 2004-09-07, modified on 2016-08-08

Applications of soil physics.

Comprehensive utilization and environmental risks of coal gangue: A review

Development of polymer-based nanosized hydrated ferric oxides (HFOs) for enhanced phosphate removal from waste effluents.

Biosensors, as an application for animal health management, are an emerging market that is quickly gaining recognition in the global market. Globally, a number of sensors being produced for animal health management are at various stages of commercialization. Some technologies for producing an accurate health status and disease diagnosis are applicable only for humans, with few modifications or testing in animal models. Now, these innovative technologies are being considered for their future use in livestock development and welfare. Precision livestock farming techniques, which include a wide span of technologies, are being applied, along with advanced technologies like microfluidics, sound analyzers, image-detection techniques, sweat and salivary sensing, serodiagnosis, and others. However, there is a need to integrate all the available sensors and create an efficient online monitoring system so that animal health status can be monitored in real time, without delay. This review paper discusses the scope of different wearable technologies for animals, nano biosensors and advanced molecular biology diagnostic techniques for the detection of various infectious diseases of cattle, along with the efforts to enlist and compare these technologies with respect to their drawbacks and advantages in the domain of animal health management. The paper considers all recent developments in the field of biosensors and their applications for animal health to provide insight regarding the appropriate approach to be used in the future of enhanced animal welfare.

Recent advances in wearable sensors for animal health management

Dairy manure is an abundant waste in dairy farming and poses handling, storage and disposal challenges. With poor management, dairy manure produces odour, ammonia and releases greenhouse gases that contribute to global warming. Anaerobic digestion (AD) is a means to produce renewable energy and to reduce environmental impacts resulting from improper management of dairy manure. Dairy manure AD suffers from low biogas production per unit mass, hence it is costly per unit volume. To improve biogas production per unit volume, anaerobic co-digestion of dairy manure is one of the methods used to enhance biogas production. This article reviews various approaches and challenges of co-digestion to enhance biogas production and methane yield that have been used in the last decade. Substrate selection and prediction of biogas production based on chemical oxygen demand are the main areas of focus. Process inhibition by co-substrates is also examined.

Prospect of anaerobic co-digestion of dairy manure: a review

Soil cone index (CI) is a widely used soil mechanical property to assess soil strength in tillage research. In this study, literature data relating CI to tillage practices are compiled into two datasets, one for no-tillage and the other for conventional tillage. Each dataset is analyzed to examine how CI varies with soil depth, textural parameters, bulk density, and moisture content. The results showed that for both no-tillage and conventional tillage, values of CI decrease with the increase in clay fraction, and increase with the increase in sand and silt fractions of soil. Similarly, higher bulk density and greater soil depth result in higher CI value, while higher moisture content reduces CI. Based on the literature data, regression equations were obtained to estimate CI under no-tillage and conventional tillage systems. In those regression equations, values of CI were linear functions of the other soil variables such as soil textural parameters and moisture content. Those regression equations were validated with field data collected from different sites in Manitoba, Canada. Over half of the results from the regression equations had good agreement with the field measurements, indicated by their relative errors of 20% or lower; however, greater discrepancies were noticed in some cases. Keywords : Tillage, soil, cone index, bulk density, moisture content, soil texture, regression

Soil cone index in relation to soil texture, moisture content, and bulk density for no-tillage and conventional tillage

Injection of manure is becoming more popular than surface spreading due to its agronomical and environmental benefits. In this study, four different existing tools (two sweep types and two disc types) for liquid manure incorporation were tested in an indoor soil bin located in the Department of Biosystems Engineering at the University of Manitoba with loamy sand, to investigate the effects of working depth (50, 100 and 150 mm) and speed (0.57 and 1.4 m/s) on soil cutting forces and soil disturbance. Draft forces and soil disturbance for all tools significantly increased with working depth, but not with working speed. Owing to its wider soil cutting width, sweep B required 80% more draft force than sweep A. For the same reason, sweep B disturbed a 44% wider soil surface along the tool passage, compared to sweep A. On the average, sweep type tools created 27% new soil pores, which would be available for containing injected manure. For the discs, vertical forces decreased with increased working depth. As compared with disc A, wider surface disturbances along the tool passage were observed for disc B due to its two concave disc design. Comparing soil disturbance for different depths, disc B may not be suitable for manure incorporation at shallow depths (50 and 100 mm). At greater depths (150 mm) both disc-type tools will favor manure coverage.

Laboratory investigation of cutting forces and soil disturbance resulting from different manure incorporation tools in a loamy sand soil

The 11 major electricity-generating coal combustion stations in the northern Great Plains have the potential to produce almost 1 million Mg of flue gas desulfurization gypsum (FGDG) annually, which is a very attractive fertilizer (Ca and S) and amendment for sodic and acid soils. The potential environmental impacts of applying FGDG to soils in this region have not been fully investigated. The objectives of this research were to determine the influence of FGDG on soil chemical characteristics and to determine the impact that FGDG has on hard red spring wheat ( L.) yields and element analysis of the grain. Flue gas desulfurization gypsum and commercial gypsum were applied at rates of 0, 2.24, 11.2, and 22.4 Mg ha to two soils in southwestern North Dakota in the spring of 2007. Soil and grain chemistries were monitored for two growing seasons. Wheat grain yields and elemental analysis of the grain were generally not affected by the gypsum treatments, indicating that the gypsum products did not negatively affect plant productivity. In addition, soil elemental analysis was similar across the treatments at both sites in both years. The results from this study indicate that its application to soil at rates used for sodic soil remediation (Mg ha) did not negatively affect the chemistries of either the soils or the wheat evaluated in this study compared with a commercial gypsum product or control soils.

Application of flue gas desulfurization gypsum and its impact on wheat grain and soil chemistry.

There is a global interest to quantify and mitigate greenhouse gas (GHG) (e.g. methane-CH4, nitrous oxide-N2O and carbon dioxide-CO2) emissions in animal feeding operations. The goal of this study was to quantify GHG emissions from the feedlot pen surface under North Dakota climatic conditions. In this study gaseous flux from the pen surfaces was generated using a custom-made wind tunnel at different times of the year (summer, fall, winter and spring). Gaseous fluxes (air samples) were drawn in the Tedlar bags using a vacuum chamber and gas concentrations were measured using a gas chromatograph within 24 h of sampling. The CH4 concentrations and flux rates (FRs) or flux among the months were not significantly different. Overall CH4, CO2 and N2O concentrations over a 7-month period were 2.66, 452 and 0.67 ppm, respectively. Estimated overall CH4, CO and N2O FRs were 1.32, 602 and 0.90 g m−2 d−1, respectively. Estimated emission rates using the wind tunnel were 38 g hd−1 d−1, 17 kg hd−1 d−1 and 26 g hd−1 d−...

Shafiqur Rahman

Papers

Prospect of anaerobic co-digestion of dairy manure: a review

Soil cone index in relation to soil texture, moisture content, and bulk density for no-tillage and conventional tillage

Laboratory investigation of cutting forces and soil disturbance resulting from different manure incorporation tools in a loamy sand soil

Application of flue gas desulfurization gypsum and its impact on wheat grain and soil chemistry.

Greenhouse gas emissions from beef cattle pen surfaces in North Dakota