Study on prevalence of bovine trypanosomosis and density of its vectors in three selected districts of Wolaita Zone, Southern Ethiopia

摘要

The study was conducted from November, 2013 to March, 2014 in three selected districts of Wolaita zone, Southern Ethiopia with objective of determining the prevalence of bovine trypanosomosis and density of its vectors. Blood samples from 480 randomly selected cattle of both sexes different age, coat color and body condition score groups were collected and examined with conventional hematological and entomological techniques. Out of total 480 cattle examined, 32(6.67%) were found to be positive for Trypanosoma congolense and Trypanosoma vivax with the individual prevalence of 5% (24/480) and 1.67 (8/480), respectively. This indicated 75% of the infection was caused by T. congolense while only 25% was by T. vivax. The areal distribution of the trypanosomosis infection was found to be 5.6, 7.3 and 7.1% in Humbo, Duguna fango and Damot woyde districts respectively. The risk factors analysis revealed that the likelihood of the occurrence of the trypanosomosis in male (p=0.046, OR=2.3, 95%CI=1.0, 5.3), age category of 3 to 7 years old (p=0.019, OR=3.2, 95% CI=1.2, 8.3), poor body conditioned animals (p=0.001, OR=12.5, 95%CI=2.8, 50.0), black coat colored animal (p = 0.02, OR=12.5, 95%CI=1.5, 117.7)? was higher when compared to female, other age categories, medium and good body condition and with other coat colored animals respectively. One way ANOVA used to compare? the PCV values of parasitemic and aparasitemic animals revealed mean PCV values in animal infected by T . congolense (21.38%) and T . vivax (23.75%). Accordingly, one way ANOVA employed to compare the mean PCV value among the three categories (Negative, Positive for T. congolense and positive for T. Vivax) revealed significant (p=0.000, F=25.8) difference in PCV values were observed. Likewise, the Bonferroni multiple comparisons test indicated the existence of significant difference (p=0.000) in the PCV value between negative group and positive group for T. congolense (p=0.000). From 90 traps deployed for three consecutive days at 6 kebeles in three districts, a total of 328 flies were caught. Of these, 37 (11.28%) belong to Glossina pallidipes, the remaining were 193 (58.84%) Tabanus and 98 (29.87%) Stomoxys. The overall apparent tsetse fly density was 0.14 flies/trap/days (F/T/D).