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Tick acaricide failure is one of the leading challenges to cattle production in Uganda. To gain an understanding into the possible drivers of acaricide failure, this study characterized the current chemical tick control practices in the southwestern (Mbarara, Mitooma and Rukungiri districts) and northwestern (Adjumani district) regions of Uganda. A total of 85 farms participated in a survey that utilized a semi-structured questionnaire. Moreover, ticks were collected to determine the most common species on the farms. Tick acaricide failure was mainly encountered in the districts where 95% (60/63) of the farms reared exotic cattle (dairy cross-breeds) under a paddocking (fenced) system. In the northwestern region, local cattle were reared in communal grazing areas. All farms used chemical acaricides for tick control, predominantly amidine (amitraz) (48%, 41/85) and co-formulated organophosphates and pyrethroids (38%, 32/85). The spraying method was the most common (91%, 77/85) acaricide application technique, with cattle crush (81%, 69/85) as a common means of physical restraint. Less than optimal tick control practices encountered included use of substandard equipment for spraying, inappropriate dilutions, frequent interaction between animals in neighboring farms despite lack of synchronized chemical tick control and malpractices in acaricide rotation. Only Rhipicephalus appendiculatus and R. (Boophilus) decoloratus ticks were found in the southwestern region, where 51% (32/63) of the farmers used high acaricide concentrations above the manufacturers' recommendation. Farmers in the northwestern region used 2.2 times less acaricide volume per cattle than those in the southwestern region, and more diverse tick species were encountered. Toxic effects of acaricide to cattle and workers were reported by 13% (11/85) and 32% (27/85) of the respondents, respectively. All 27 cases of human acaricide toxicity reported were from the southwestern region. Overall, our findings may inform strategies for more prudent chemical tick control and safe acaricide handling to benefit animal welfare, food safety and public health., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

The emergence of multi-acaricide resistant ticks has led to unprecedented level of acaricide failure in central and western Uganda. In the absence of a national acaricide resistance management strategy, the country's dairy sector is threatened by upsurge of ticks and tick-borne diseases. In this study, we developed a short-to-medium-term intervention approach called Evidence-Based Acaricide Tick Control (EBATIC): Identify, Test, Intervene and Eradicate (IT-IE). Furthermore, the perception of 199 farmers and extension workers, 12 key informants in four districts and 47 stakeholders in the animal industry in Uganda were assessed using semi-structured questionnaires. We report that the establishment of a specialized laboratory is pivotal in identifying and testing (IT) acaricide resistant ticks for prompt intervention and eradication (IE). The laboratory test results and the farm tick control gaps identified are very important in guiding acaricide resistance management strategies such as evidence-based acaricide rotation, development and dissemination of extension materials, training of farmers and extension workers, and stakeholders' engagement towards finding sustainable solutions. All the 47 stakeholders and 91.0% (181/199) of the farmers and extension workers reported that the EBATIC approach will help in solving the tick acaricide resistance crisis in Uganda. Similarly, all the 12 key informants and 92.5% (184/199) of the farmers and extension workers suggested that the EBATIC approach should be sustained and rolled out to other districts. The EBATIC stakeholders' dialogue generated both short-to-medium and long-term strategies for sustainable management of tick acaricide resistance in the country. Overall, the positive feedback from farmers, district veterinarians and stakeholders in the animal industry suggest that the EBATIC approach is a useful proof-of-concept on scalable intervention pathway against tick acaricide resistance in Uganda with possibility of adoption in other African countries., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Livestock production is a major sector of the Ugandan economy. Ugandan ruminant livestock (principally cattle and goats) are susceptible to hemoparasites that can cause serious clinical disease and production losses. Kibale National Park, in western Uganda, is a protected forest ecosystem surrounded by small-scale farms where cattle and goats are raised. We conducted a cross-sectional study of cattle and goats in this area and diagnosed hemoparasite infections by microscopy. We collected data on animal characteristics and management practices to assess risk factors associated with infection. We studied 186 cattle and 317 goats from 20 villages, including 16 villages directly adjacent to Kibale and 4 villages ≥3 km from the park boundary. Hemoparasites detected in cattle and goats were of the genera Theileria, Anaplasma, and Trypanosoma with a prevalence of 15.1%, 1.6%, and 4.3% respectively in cattle, and 10%, 6.0%, and 0.0%, respectively in goats. Trypanosomes infected approximately 8% of cattle in villages bordering Kibale but were never detected in cattle in "control" villages ≥3 km from the park. Trypanosomes were approximately 7 times more likely to infect animals in households that did not provide veterinary care to their animals than in households that provided routine veterinary care. Within cattle, Theileria infections were approximately 7 times more likely to occur in cross-bred cattle than in indigenous pure breeds. Anaplasma infections were approximately 3.5 times more likely to occur in cattle than in goats (no goats were diagnosed with Trypanosoma infection). These data suggest that proximity to the park, provision of veterinary care, and breed are significant risk factors for hemoparasites in this population of ruminants, and that, in general, cattle are more susceptible than goats.

Background: Acaricide failure has been on the rise in the western and central cattle corridor of Uganda. In this study, we identified the tick species associated with acaricide failure and determined their susceptibility to various acaricide molecules used for tick control in Uganda., Methods: In this cross sectional study, tick samples were collected and identified to species level from 54 purposively selected farms (from 17 districts) that mostly had a history of acaricide failure. Larval packet test was used to screen 31 tick populations from 30 farms for susceptibility at discriminating dose (DD) and 2 × DD of five panels of commercial acaricide molecules belonging to the following classes; amidine, synthetic pyrethroid (SP), organophosphate (OP) and OP-SP co-formulations (COF). Resistance was assessed based on World Health Organization criteria for screening insecticide resistance., Results: Of the 1357 ticks identified, Rhipicephalus (Rhipicephalus) appendiculatus and Rhipicephalus (Boophilus) decoloratus were the major (95.6%) tick species in farms sampled. Resistance against SP was detected in 90.0% (27/30) of the tick populations tested. Worryingly, 60.0% (18/30) and 63.0% (19/30) of the above ticks were super resistant (0% mortality) against 2 × DD cypermethrin and deltamethrin, respectively. Resistance was also detected against COF (43.3%), OP chlorfenvinphos (13.3%) and amitraz (12.9%). In two years, 74.1% (20/27) of the farms had used two to three acaricide molecules, and 55.6% (15/27) rotated the molecules wrongly. Multi-acaricide resistance (at least 2 molecules) was detected in 55.2% (16/29) of the resistant Rhipicephalus ticks and significantly associated with R. decoloratus (p = 0.0133), use of both SP and COF in the last 2 years (p < 0.001) and Kiruhura district (p = 0.0339). Despite emergence of amitraz resistance in the greater Bushenyi area, it was the most efficacious molecule against SP and COF resistant ticks., Conclusion: This study is the first to report emergence of super SP resistant and multi-acaricide resistant Rhipicephalus ticks in Uganda. Amitraz was the best acaricide against SP and COF resistant ticks. However, in the absence of technical interventions, farmer-led solutions aimed at troubleshooting for efficacy of multitude of acaricides at their disposal are expected to potentially cause negative collateral effects on future chemical tick control options, animal welfare and public health.