The burden and spatial distribution of bovine African trypanosomes in small holder crop-livestock production systems in Tororo District, south-eastern Uganda

African animal trypanosomiasis (AAT) is considered to be one of the greatest constraints to livestock production and livestock-crop integration in most African countries. South-eastern Uganda has suffered for more than two decades from outbreaks of zoonotic Human African Trypanosomiasis (HAT), adding to the burden faced by communities from AAT. There is insufficient AAT and HAT data available (in the animal reservoir) to guide and prioritize AAT control programs that has been generated using contemporary, sensitive and specific molecular techniques. This study was undertaken to evaluate the burden that AAT presents to the small-scale cattle production systems in south-eastern Uganda. Randomised cluster sampling was used to select 14% (57/401) of all cattle containing villages across Tororo District. Blood samples were taken from all cattle in the selected villages between September-December 2011; preserved on FTA cards and analysed for different trypanosomes using a suite of molecular techniques. Generalized estimating equation and Rogen-Gladen estimator models were used to calculate apparent and true prevalences of different trypanosomes while intra cluster correlations were estimated using a 1-way mixed effect analysis of variance (ANOVA) in R statistical software version 3.0.2.ResultsThe prevalence of all trypanosome species in cattle was 15.3% (95% CI; 12.2-19.1) while herd level trypanosome species prevalence varied greatly between 0-43%. Trypanosoma vivax (17.4%, 95% CI; 10.6-16.8) and Trypanosoma brucei rhodesiense (0.03%) were respectively, the most, and least prevalent trypanosome species identified. The prevalence of bovine trypanosomes in this study indicates that AAT remains a significant constraint to livestock health and livestock production. There is need to implement tsetse and trypanosomiasis control efforts across Tororo District by employing effective, cheap and sustainable tsetse and trypanosomiasis control method that could be integrated in the control of other endemic vector borne diseases like tick-borne diseases

Volumetric water pricing, social surplus and supply augmentation

We evaluate the welfare losses of undertaking water supply augmentation in Sydney, Australia with a fixed, regulated water price given weather variability. Stochastic dynamic programming is used to determine dynamically efficient water prices and to estimate the losses in social surplus from premature water supply augmentation. Results show that premature water supply augmentation under the base case reduces the net present value of the welfare of households by more than $A 3 billion, or some$A 1900 NPV per household. With a broad range of parameters controlled in our sensitivity analysis, the actual construction time of the water plant is associated with a net loss, unless the lifetime of the plant is exceptionally long in combination with a low discount rate. While the findings are specific to Sydney, our modeling is of general interest because it could be employed to avoid costly and premature supply augmentation elsewhere

Intertemporal and spatial location of disposal facilities

Landfilling, Exhaustible resources, Optimal capacity, Optimal location, Global optimization, C61, C63, Q30, R53,