Field observations on the duration of immunity in cattle after vaccination against Anaplasma and Babesia species

In an outbreak of Babesia bovis in a large herd of Friesian x Malawi Zebu cattle, which occurred after an interruption of intensive dipping, clinical or fatal babesiosis occurred in 54/299 (18,1 %) animals which had never been vaccinated, as compared to 9/153 (5 ,9 %) vaccinated animals. Eight of the nine affected vaccinates had been vaccinated more than 27 months previously. Sera were collected every 3-4 months from 33 Friesian x Malawi Zebu heifers maintained with intensive dipping and vaccinated with trivalent B. bovis, Babesia bigemina and Anaplasma centrale vaccine. After 2 years, 25% had become seronegative for B. bovis by indirect immunofluorescence, as compared to 97% for B. bigemina and 46% for A. centrale. Because of the evidence that immunity following vaccination against B. bovis declines after 2 years in the absence of tick challenge, it is recommended that tick control should be relaxed after immunity has been established, in order to save acaricide, reinforce immunity and avoid any need for revaccination.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Danish Aid Organization (DANIDA). Government of Malawi

Antibodies against foot and-mouth disease (FMD) virus in African buffalos (Syncerus caffer)

Abstract: The aim of this study was to determine the seroprevalence and serotype-specificity of the circulating antibodies against Foot-and-Mouth Disease Virus (FM DV) in cattle in Kasese and Bushenyi districts in Uganda. A total of 309 serum samples were collected and tested for antibodies against Non-Structural (NS) and Structural Proteins (SP) using Ceditest® FMDV-NS and Ceditest® FMDV type O test kits. Seroprevalences were much higher in Kasese in both tests (61 and 43%, respectively) than in Bushenyi (3 and 4%, respectively). A high proportion of sera, that tested positive in the NSP test, were subjected to seven serotype specific blocking ELISAs for antibodies against the seven FMDV serotypes (O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3). The study showed presence of antibodies against four FMDV serotypes with decreasing magnitude as follows: O> SAT 1> SAT 3/SAT 2. It is recommended to develop sampling schemes to include virus recovery and identification, as well as to focus serum sampling on young unvaccinated stock

How and Why Software Outsourcing Projects Drift—An Actor-Network-Theoretic Investigation of Control Processes

This study seeks to explain the perplexing phenomenon that many software outsourcing projects drift, ie, they enter into a creeping process of targeting emergent goals often at the expense of losing sight of initial goals. Such drift is difficult to reconcile with the traditional logic of control found in the literature. According to this logic, clients should be able to ensure goal achievement through close monitoring. If drift occurs despite rigid control, this suggests that within the control process forces are at work that divert controls from their initial objectives. To better understand these forces in the control process and how they relate to drift, we contrast the logic of control with concepts and assumptions from actor-network theory (ANT). ANT allows us to understand the process of designing, enacting, and adapting controls as one of creating and changing actor-networks. Our longitudinal case study of four software outsourcing projects reveals that drift processes differ depending on three interconnected changes in the actor-networks, ie, changes in who partakes in the (re-) negotiation of control mechanisms, what specific control mechanisms are (re-) defined, and how they are inscribed in the software artifact and the software task