Trypanosomosis: a priority disease in tsetse-challenged areas of Burkina Faso

Trypanosomosis is an important disease affecting humans as well as animals. It remains a big constraint to livestock productions in tropical areas. The objective of this study was to assess the importance of trypanosomosis among cattle diseases in Burkina Faso, mainly in tsetse-challenged areas, and to capture information on how farmers apply available methods for controlling the disease. A survey has been carried out in 29 villages of Burkina Faso in three regions (north, southwest, and west regions). One hundred and thirty-four cattle breeders were interviewed individually with a questionnaire. The results indicate that among the 16 diseases mentioned by cattle breeders, trypanosomosis is the most important one in tsetse-challenged areas. Overall, 76.12 % of the breeders mentioned it as the most important disease, while 54.55 % of the farmers in the southwest region and 70.91 % of the farmers in the west region ranked it as a priority disease. Chemoprophylaxis/chemotherapy is widely used as a control method. Isometamidium chloride and diminazene aceturate were used by 53.49 and 46.52 % of the responders, respectively. Among farmers, 85.55 % ranked diminazene aceturate as the less efficient while 14.45 % ranked isometamidium chloride as the most efficient trypanocid. Trypanocidal drug quality and drug resistance were raised as a major concern by 30.77 and 50 % of the respondents, respectively. According to them, zebu cattle are more susceptible to trypanosomosis than taurine Baoule cattle and their crosses with zebu, emphasizing that crossing susceptible breeds with trypanotolerant ones, could be used as part of an integrated control strategy.     

Effect of tillage intensity on N mineralization of different crop residues in a temperate climate

To evaluate the effect of tillage intensity on the N mineralization pattern of winter wheat residues, sugar beet residues, Italian ryegrass and maize residues undisturbed soil samples were taken from six sites under different tillage management. Site NT_K had been managed for 10 years under reduced tillage (RT), whereby the last 4 years the crops were sown using direct seeding (NT). Site RT_CSE had been managed for 20 years under reduced tillage (RT) and site RT_H for 3 years. For each site under RT a nearby site under conventional tillage (CT) was selected (CT_K, CT_CSE and CT_H). On site NT_K and site RT_CSE a significantly higher amount of SOC in the 0–10 cm was accumulated compared to the respective CT sites. Between site RT_H and site CT_H no such significant difference was found. However, the content of microbial biomass C (MB-C) and the β-glucosidase and urease activities were higher on all RT sites compared to the respective CT sites. This indicates that these microbiological and biochemical parameters seem to be very sensitive for alterations in management intensity. After 98 days, more N was immobilized under NT_K than under CT_K by adding winter wheat residues (expressed as kg ha⁻¹ and as % of total added N). This higher immobilization potential can be explained by a higher microbial activity and a change in microbial population. Under RT_CSE and RT_H net N immobilization of the winter wheat residues was found, but the pattern was less pronounced than for NT_K. However, when expressed as % of total N added, N immobilization of winter wheat residues was higher under CT than under RT, which indicates that high C:N residues when incorporated, decompose more slowly under RT than under CT. Similar results were found comparing the N mineralization pattern of maize residues under RT_H and CT_H. The residues of sugar beet and Italian ryegrass at site CT_H released N more rapidly and to a higher extent, 74.1% and 66.2%, respectively (expressed as % of total N added) than under RT_H at the end of the incubation. The slower mineralization of N rich crop residues under RT compared to CT means that there is less potential risk for nitrate leaching to occur, which may result in a higher N efficiency in RT compared to CT.