Knowledge and attitudes of cattle owners regarding trypanosomosis control in tsetse-infested areas of Uganda.

A pilot survey using a structured questionnaire was conducted in Tororo and Busia districts of Uganda on the knowledge and attitudes of cattle owners regarding tsetse fly and trypanosomosis control, in order to understand factors that hindered their full participation. A total of 81 cattle owners was randomly selected and interviewed, of which 92.5% were aware of tsetse flies and trypanosomosis and 87.6% recognised animal trypanosomosis as a problem in the area. Most cattle owners were aware of tsetse fly trapping (76.5%), isometamidium chloride use (55.5%), diminazene aceturate use (48%) and pour-on applications (18.5%). However, knowledge did not coincide with the application of control measures. Despite the widespread awareness, tsetse fly trapping and pour-on applications were used by only a small percentage of cattle owners (7.5% applied tsetse fly trapping while 76.5% were aware of it; 1.2% applied pour-on insecticides while 18.5% were aware of them). Differences between awareness and application were highly significant for tsetse fly trapping (chi2 = 67.8, d.f. = 1, P < 0.001) and pour-on applications (chi2 = 10.8, d.f. = 1, P < 0.05), but not for isometamidium chloride use (chi2 = 0.08, d.f. = 1, P = 0.77) and diminazene aceturate use (chi2 = 0.00, d.f. = 1, P = 1.00). Most cattle owners (97.5%) were willing to participate in future control programmes, but preferred participating on a group basis (85.2%) rather than individually (14.8%). The 4 most favoured control options in order of importance were: fly traps supplied by the government and maintained by cattle owners; contribution of labour by cattle owners for trap deployment; self-financing of trypanocidal drugs and self-financing of pour-on insecticide. The control options that should be selected in order to elicit full participation by cattle owners are discussed.

The use of trypanocides and antibiotics by Maasai pastoralists.

Information was collected on the use of veterinary drugs by Maasai pastoralists in an area of Kenya where tsetse flies and trypanosomosis occur. Three herds of cattle were followed for between 4 and 5 years and records were kept of every veterinary drug treatment given by the livestock owners. Almost all treatments were either with the trypanocides homidium or diminazene, or with oxytetracycline by intramuscular injection. The rate of trypanocide use varied between 0.66 and 1.56 treatments per animal per year, while oxytetracycline use was between 0.20 and 1.00 treatments per animal per year. Farmers were injecting these drugs in the absence of veterinary supervision, obtaining their supplies mainly from local village shops or informal traders. Underdosing with trypanocides appeared to be uncommon and the indications were that farmers generally gave the drugs at dosage rates above the recommended standard dose. Accurate information on the dose rates of oxytetracycline could not be obtained, but it was noted that in most cases farmers gave a single injection rather than a course of treatment. In a proportion of cases, trypanocides and antibiotics were mixed together before injection. The farmers administered the drugs when disease was recognized and were rarely using trypanocides as prophylactics. Although necessity forces the livestock owners to obtain and use these drugs without veterinary supervision, there are concerns with regard to the possibility of drug misuse and the development of drug resistance.

A financial analysis of treatment strategies for Trypanosoma evansi in the Brazilian Pantanal.

The Brazilian Pantanal is a 138,000 km2 tropical seasonal wetland located in the center of South America bordering Bolivia and Paraguay. The Pantanal contains approximately 1100 cattle ranches, 3 million cattle, 49,000 horses and a unique diversity of wildlife. Cattle ranching is the most important economic activity in the Pantanal. This study explores the direct financial impacts of the adoption of seven treatment strategies for the control of Trypanosoma evansi in the Brazilian Pantanal. T. evansi adversely affects the health of the horse population in the region. Horses are indispensable to the cattle ranching industry in the Pantanal. Estimated costs include risk of infection, costs of diagnosis, alternative treatments, collecting animals for treatment, and costs of animal losses. The estimated total cost of T. evansi to the Pantanal region's cattle ranchers is about US$2.4 million and 6462 horses/yr. Results indicate that one preventive and two curative treatment strategies are financially justifiable. The best available technology for the treatment of T. evansi from an economic perspective is a curative treatment employed year-round. This treatment represents an annual net benefit of more than US$2 million or US$1845/ranch and spares about 5783 horses. It represents an annual net benefit of over US$200,000 and 600 horses relative to the currently most widely adopted strategy.

Changes in haematocrit after treatment of uncomplicated canine babesiosis: a comparison between diminazene and trypan blue, and an evaluation of the influence of parasitaemia.

It has been suggested that the antibabesial drug diminazene causes a rapid decline in haematocrit after treatment of dogs with high Babesia canis parasitaemias, compared with trypan blue. To test this, 19 dogs with clinically mild to moderate, uncomplicated babesiosis were placed in low, moderate or high parasitaemia groups, based on venous parasitaemias, and were allotted randomly to diminazene or trypan blue treatment groups. Haematocrit and parasitaemia were determined before treatment, and at 2, 6, 12, 18 and 24 hours. The drugs were compared for effects on haematocrit and parasite clearance. Changes in haematocrit after treatment were analysed. There were no significant differences between diminazene and trypan blue for haematocrit or parasite clearance. There was no correlation between initial parasitaemia and initial or post-treatment haematocrit. In all dogs, haematocrit fell following treatment. The maximum mean reduction from the baseline (0 h) was 0.046 l/l (range 0.02-0.07 l/l); this most often occurred at 6 or 12 h. The 24 h haematocrit ranged from 70.5-113.6% of baseline (mean absolute haematocrit 0.019 l/l below baseline). All dogs improved clinically during the study period. It was concluded that either diminazene or trypan blue can be safely used to treat dogs with clinically mild or moderate, uncomplicated babesiosis. Parasitaemia need not be taken into account when deciding which antibabesial drug to administer and does not appear to be related to the degree of anaemia.