Veterinary Parasitology

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    Control of Tsetse and Trypanosomosis in the Southern Rift Valley (Step Area): Evaluation of Deltamethrin Applications
    (2004-06) JEMERE, BEKELE; Prof. Getachew Abebe
    A trial aimed to evaluate the efficacy of Deltamethrin (0.4% impregnated odour-baited targets and 1% pour-on formulation applied to animals) in reducing the incidence of bovine trypanosomosis and comparing the corresponding cost-effectiveness of both strategies was conducted in two selected 10X10km Universal Transverse Mercator Grids of the Southern Tsetse Eradication Project (STEP) area in the Southern Rift Valley of Ethiopia. The Grids selected were H3 & G5 designated as study Sites I & II respectively. The trial was underway from late September, 2003 to early April, 2004. The accomplishment of the trial included baseline survey (Questionnaire, Parasitology, and entomology), intervention with insecticide (Deltamethrin 0.4%) impregnated odour-baited targets at Site I(Grid H3) and Deltamethrin 1% ‘pour-on’ application to cattle at Site II (Grid G5) and monthly monitoring of the incidence of disease and apparent density of tsetse fly. Following the deployment of 460 targets (0.4% Deltamethrin impregnated and odour-baited) at a density of 4 targets /km2 at the trial Site I, the relative abundance of tsetse fly (G. pallidipes) population declined from a pre-intervention catch of 1.35 flies/trap/day to 0.05 flies/trap/day during the final trapping time in April, 2004 with about 88.88% overall reduction achieved. The associated disease (trypanosomosis) status was monitored by monthly blood sampling from the sentinel animals established prior to the intervention and the incidence in cattle dropped from 10.75% (first monitoring) to 1.8% (last monitoring) with about 83.25%. The prevalence of the disease had also dropped to 9% (P< 0.01) as compared to the pre-intervention result of 23% and as a result, an overall reduction of 60% was achieved. The corresponding overall mean PCV (packed cell volume) record had shown an improvement from 21.8% of the pre-intervention to 25.5 % (P<0.01) after intervention. Similar assessment at Site II with Deltamethrin 1% pour-on formulation started by applying to about 409 animals at a rate of 1ml/10 kg body weight and subsequently repeated on monthly basis throughout the trial period resulted in a sharp drop of the relative abundance of tsetse fly population to nil from 0.91 flies/trap/day of the pre-intervention catch with a 94.88% (P<0.01) overall reduction achieved. The incidence of the disease also declined from 10% to 0.95% (about 90.5%). The reduction from 21% to 4.75% in the prevalence of the disease was observed to be significant (P<0.01) with a 77.4% overall drop. The associated overall mean PCV value (24.1% increased to 27.2%) had shown a gradual increase (P<0.01) until the third monitoring and maintained a stable state thereafter. The use of Deltamethrin 1% pour-on proved better efficacy based on the results obtained and conclusions made. In addition to this, cost effectiveness evaluation of the intervention component was conducted. This indicated that the routine intervention cost for Pour-on formulation offered Incremental Cost-Effectiveness Ratio (ICER) ranging from 34762.54- 102927.94 USD per unit effectiveness and the use of impregnated odour-baited targets ranging from 43184.93- 942652.00 USD per unit effectiveness for tsetse control and the associated disease (trypanosomosis) reduction. The ranges imply that reasonable variation is lacking between the cost-effectiveness of the two strategies. Though this uncertainty interval ruled out the difference between using targets and pour-on, it seemed that pour-on having lower ICER on average cost and average effectiveness assessments. The integrated application of both strategies was definitely relevant and thus recommended.
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    PREVALENCE OF CAMEL TRYPANOSOMOSIS AND ASSOCIATED RISK FACTORS IN SELECTED DISTRICTS OF BALE ZONE, ETHIOPIA
    (2007-06) ESAYAS, TESEMA; Dr. Yilkal Asfaw, Dr. Hagos Ashenafi
    A cross sectional study was conducted to determine the prevalence of camel trypanosomoses and to identify the risk factors associated with the disease occurrence in Dello-mena and Sawena districts of Bale zone. Blood samples were collected from 619 camels and examined for the presence of T. evansi using card agglutination test for trypanosomiasis (CATT / T. evansi), and a parasite detection test (buffy coat smear – BCS). Clinical examinations as well as questionnaire survey, regarding information about the host and management practices were conducted. Questionnaire survey results indicated that high milk production, bush encroachment as well as the ability to survive drought are the major reasons for camel keeping. Camel trypanosomoses locally known as “Dhukan” is the most important complaint of camel breeders. Respondents clearly described the diseases and ranked it as the most important disease of camel in the study area. The prevalence of the disease was found to be 12.12% using buffy coat smear and 24.88% with CATT. Camels in Dello-mena had a significantly higher prevalence than camels in Sawena district in both BCS and CATT / T. evansi examination results. Thus it was found that camels in riverine areas of Dello-Mena are more at risk of infection than herds in non-riverine areas of Sawena. Age appeared to be a risk factor for individual trypanosomoses serological status and that the highest seroprevalence was observed in camels greater than five years old. Poor body condition was significantly correlated with positive status in both CATT and BCS results. The average PCV of parasitological positive camels was found to be significantly different from the average PCV of parasitological negative camels. However, the average PCV of seropositive but parasitological negative camels did not differ from the average PCV of seronegative camels. From the result of this study it can be inferred that camel trypanosomoses is endemic in dello-mena and Sawena districts with a higher degree of prevalence in Dello-mena than Sawena district. Absence of proper animal health extension and the indiscriminate use of camel trypanocidal drugs often underdosed are major constraints in camel health delivery in the study area. Thus, attention has to be given to provide adequate veterinary service and sensible animal health extension systems. Furthermore, considering the widespread existence of surra and its impact on camel productivity further study on identification of the principal vector species responsible for transmission and investigating the potential for vector control is recommended.
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    STUDIES ON PREVALENCE, ECONOMIC AND PUBLIC HEALTH IMPORTANCE OF HYDATIDOSIS IN SLAUGHTERED ANIMALS AT ADDIS ABABA ABATTOIR, ETHIOPIA
    (2008-06) KEBEBE, ERBETO; Dr. Girma Zewde, Dr. Bersissa Kumsa
    A cross sectional survey was conducted from November 2007 to April 2008 with the following objectives, to determine the prevalence of hydatidosis in food animals slaughtered at Addis Ababa Abattoir, study the effect of risk factors on the prevalence of hydatidosis, evaluate the size, fertility and viability of the cysts, assess the economic losses and the public health significance of the disease. Routine meat inspection procedures was conducted whereby livers, lungs, hearts, kidneys and spleens were visualized, palpated and incised to detect the presence of the cysts. The sizes of the cysts were determined by measuring the diameters in cm. Fertility was evaluated by observing the presence of protoscoleces under the microscope and viability was determined. The annual economic losses were calculated by multiplying the number of annually condemned organs with the current market value of organs. The public health significance was assessed by structured questionnaire survey. Out of the total of 3430 cattle, sheep, goats and pigs slaughtered and inspected at Addis Ababa Abattoir, 639 (18.6 %) had hydatid cysts. Prevalence of 254 (21 %), 206 (19.9 %), 102 (16 %) and 77 (14 %) were recorded in cattle, sheep, goats and pigs, respectively. Prevalence of 132 (20.9 %), 85 (22.4 %) and 37 (18.7 %) was registered in cattle of Borana, Arsi and Abyssinian Zebu breeds, respectively. There was no significant variations by cattle breeds. Even though higher prevalence was detected in cattle from midland areas 124 (21.3 %) than in cattle originated from lowland areas 130 (20.5 %), there was no significant difference in prevalence in cattle from the two origins. The prevalence in cattle were found infected in age of > years old, 125 in age of 4-6 years (49%), and < 2 -4 years old 12 (4.7 %). Prevalence of 88 (8.5 %), 53 (5.1 %) and 65 (6.3 %) was recorded in Black Head – Ogaden, Adal and Abyssinian sheep breeds, respectively. Sheep under less than 1 year 77 (7.4 %) was more infected than sheep above 3 years of age 11 (1.1 %) and the difference in prevalence was significant. The prevalence of hydatidosis in Arsi- Bale and Keffa goat breeds were 53 (8.3 %) and 49 (7.6 %), respectively. The frequency of infection was higher in pigs kept at backyard 55 (10 %) than those managed under intensive husbandry system 22 (4 %). Out of the total 2071 cysts isolated from the different organs of cattle, 1007 (48.6 %) were small, 711 (34.3 %) medium and 353 (17 %) were large. More cysts were counted in the lungs of cattle, sheep and goats, but more cysts were found in swine's liver than in lung. Out of the total of 396 cysts isolated from organs of cattle, 217 (54.8 %) were fertile, 133 (33.6 %) sterile and 46 (11.6 %) were calcified. Out of X the 217 fertile cysts, 185 (85.3 %) were viable and 32 (17.3 %) were none viable. The annual economic loss was estimated to be 10,923,601.00 Ethiopian Birr, which is equivalent to 1,139,061.63 USD. 234 cases of human hydatidosis were surgically treated at the Tikur Anbassa Referral Hospital in Addis Ababa. The economic and public health significance of the disease is discussed and pertinent conclusions are drawn.
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    EPIDEMIOLOGICAL STUDY OF BOVINE TRYPANOSOMOSIS IN GORO AND AMEYA-KOTA DISTRICTS OF SOUTHWEST SHOA ZONE, OROMIA NATIONAL REGIONAL STATE, ETHIOPIA
    (2008-06) TILAHUN, AYELE; Dr. Yilkal Asfaw, Dr. Yakob Hailu
    An epidemiological study of bovine trypanosomosis was carried out from September 2007 to March 2008 in Goro and Ameya-Kota districts of Southwest Shoa Zone, Oromia National Regional State, Ethiopia. The objectives of the study were to determine the prevalence of the disease and associated risk factors, evaluate the apparent densities and distributions of tsetse and other biting flies and to know the community awareness concerning the disease and control method in the study area. The study methodology comprises seasonal cross-sectional studies in late rainy and dry seasons in 2007/2008 by using parasitological, entomological and questionnaire surveys. A total of 1200 animals, 600 in the late rainy and 600 in the dry seasons, were examined and the prevalence of trypanosomosis was found to be 33.5% and 17.83% in the late rainy and dry seasons, respectively, with a statistically significant difference (p<0.05) between seasons. The mean PCV values of the parasitaemic and aparasitaemic animals during the late rainy season were 20.19% and 26.75% while during the dry season 18.75% and 23.97% respectively. The entomological survey showed that G.pallidipes, G.m.submorsitans and G.f.fuscipes were prevalent tsetse species along with other biting flies (tabanids and muscids) in the study area. The apparent densities of tsetse flies were statistically significantly different (p<0.05) between the late rainy season (1.05 fly/trap/day, 0.26 fly/trap/day, 1.56 fly/trap/day) and the dry season (0.56 fly/trap/day, 0.11 fly/trap/day 0.59 fly/trap/day) for G. pallidipes, G. morsitans submorsitans, G.fuscipes fuscipes, respectively. The overall apparent densities of tsetse flies were found to be 2.87 fly/trap/day (95% CI= 1.04-5.77%) and 1.26 flay/tap/day (95% CI= 1.17-2.07%) in late rainy and dry seasons, respectively. G.f.fuscipes and G.pallidipes appears to be dominant during the course of the study period, whereas lower catch was observed for G.m.submorsitans than G.pallidipes and G.f.fuscipes. The proportion of female tsetse flies caught was higher in both seasons. G.pallidipes was considered to be active transmitter of the disease compared to G.m.submorsitans and G.f.fuscipes. Also the apparent densities of other biting flies were significantly higher (p<0.05) in the late rainy season (1.49 fly/trap/day, 18.66 fly/trap/day) than the dry season (0.77 fly/trap/day, 15.04 fly/trap/day) for tabanids and muscids, respectively. The overall apparent densities of biting flies were found to be 20.15 fly/trap/day (95% CI= 14.23-26.03%), and 15.81 fly/trap/day (95% CI= 10.86-20.75%) in late rainy and dry seasons, respectively. The questionnaire survey revealed that trypanosomosis is the most economically X important disease affecting cattle in Goro and Ameya-Kota sites of the study area. All of the interviewed farmers indicated that bovine trypanosomosis ranks first as the major animal health constraint impairing agricultural development. Also they suggested that the occurrence of trypanosomosis was higher in the late rainy season than the dry season. Most of the curative and preventive trypanocidal drugs in the study area were misused by drug smugglers and non professionals. Hence, trypanosomosis is the most important challenge for agricultural activity and animal production in Goro and Ameya-Kota districts, and the situation is getting worse as the control and prevention of trypanosomosis is facing a lack of vector control activities in the area.
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    STUDIES ON THE INTERACTIONS BETWEEN OESTRUS OVIS (L1) AND HAEMONCHUS CONTORTUS (L3) IN EXPERIMENTALLY INFECTED GOATS
    (2008-06) Basaznew, Bogale; STUDIES ON THE INTERACTIONS BETWEEN OESTRUS OVIS (L1) AND HAEMONCHUS CONTORTUS (L3) IN EXPERIMENTALLY INFECTED GOATS
    Concurrent parasitic infection of animals is a common phenomenon in the field. The existence of one species may often positively or negatively influences the biology and development of the other. The results of previous experimental studies on sheep model under temperate conditions have shown that infection with Oestrus ovis adversely affected populations of either Haemonchus contortus or Trichostrongylus colubriformis. However, under tropical condition no information was available on the interactions between the parasites located in remote anatomical site mainly using goat model. Hence, an experimental study was conducted with the objective to determine the possible occurrences of interactions between O. ovis and H. contortus using specifically Ethiopian local Afar breed of goats. A total of twenty goats were allocated into four groups (O, OH, H, and C) of five animals. Groups O and OH animals, each received a total of 56 first instar larvae (L1) of O. ovis in five consecutive infections between days 0 and 35, and then on day 42 animals from groups OH and H were infected with a single dose of 5000 third stage larvae (L3) of H. contortus. Goats from group C were kept free of any infection as non-infected controls. Faecal egg counts (FEC), blood cell counts, total serum protein levels and body weight changes were measured weekly throughout the study period. All experimental animals were humanly killed on day 98. At necropsy worm burden, female worm length and fecundity as well as O. ovis larval burdens in the nasal-sinus cavities of infected animals were assessed. The results showed that the presence of H. contortus in the abomasum of group OH had no any influence on the development of O. ovis in the nasal-sinus cavities. In contrast, infections with O. ovis before H. contortus was related with significant reduction (P<0.05) in FEC, worm burdens, fecundity and female worm length in group OH compared with mono-infected animals (group H). This was associated with in higher blood eosinophilia and packed cell volumes (PCV) which was significantly different (P<0.05) from O. ovis mono-infected animals.
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    A CROSS SECTIONAL STUDY OF DOURINE IN SELECTED HORSE BREEDING DISTRICTS OF BALE HIGHLANDS OF OROMIA REGIONAL STATE OF ETHIOPIA
    (2008-06) DEGEFA, GUTA; Dr. Hagos Ashenafi, Dr. Yacob Hailu,
    A cross sectional study comprising serological and questionnaire survey was conducted with the objective of determining the prevalence, extent and distribution of Dourine in selected horse breeding districts of Bale highlands of Oromia Regional State of Ethiopia from September 2007 to May 2008. Parasitological survey in an attempt to determine the parasitological prevalence and to isolate T. equiperdum in 71 purposively selected clinical Dourine cases revealed no trypanosomes by Giemsa staining or by Haematocrit Centrifugation Technique (HCT). A total of 880 sera were tested for the detection of antibodies against the causative agent of Dourine in four selected horse breeding districts of the Bale highlands of Ethiopia. Accordingly, the sero prevalence of Dourine was found to be 140 (15.90 %) and 173 (19.66 %) for CATT / T. evansi and LATEX / T. evansi tests, respectively. Body condition and parity number were found to have significant difference (p < 0.05) on the sero prevalence of the disease based on the CATT/ T. evansi test only. However, age, sex, history of previous abortion and castration status no significant difference (p > 0.05) on the sero prevalence of the disease using CATT/ T. evansi test. On the other hand neither of the explanatory variables had significant difference (p > 0.05) using LATEX/ T. evansi test. Logistic regression analysis revealed that horses without parity number (0) had an OR of 1.80 (1.02, 3.19) positivity compared to horses with parity number (1 and above); and horses with poor body condition (thin and very thin) had an OR of 1.44 (1.00, 2.08); positivity compared to horses with moderate body condition (less thin, less moderate and moderate) scores, on the basis of CATT/ T. evansi test. The questionnaire survey indicated that dourine is the major health problem of horses in the selected horse breeding districts of Bale highlands of Ethiopia and locally known as “Derisa” in Oromifa language and “Tigen” in Amharic language that causes high mortality and economic loss in selected horse breeding districts of Bale highlands of Ethiopia. It is a common clinical case throughout the year, however the disease has a seasonal character, which most commonly occurs whenever animals are in a good body condition and following the breeding season from April to late September and during dry season of the year (January to March), which probably associated with the relapse of previously infected and recovered cases due to the stressful condition of feed shortage. Uncontrolled breeding, unrestricted animal movement and absence of officially approved effective trypanocidal drugs against dourine cases are the main factors that play an important role in the distribution and transmission of the disease. X Even though there was no direct parasitological detection of T. equiperdum, the result of serological survey conducted by using CATT / T. evansi and LATEX / T. evansi tests together with the questionnaire survey, provides strong evidence that Dourine is highly prevalent, most important problem in selected horse breeding districts of Bale highlands of Ethiopia, where the problem of dourine is still unsolved. Further more, in view of large number of horses in Ethiopia and the unrestricted movement of animals throughout the country it is likely that dourine may be more widespread in Ethiopia than is currently realized.
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    Study on Basic Heamatological Serum Biochemical and Parasitological Parameters in Exprimentally Sheep by Differnt Infective Doses of Haemonchus Contortus(L3)
    (Addis Ababa University, 2008-06) Ashine, Fantu; Hailu, Yacob(phD)
    Astud to assess Changes in Haematological Serum Biochemical
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    A CROSS SECTIONAL STUDY OF DOURINE IN SELECTED HORSE BREEDING DISTRICTS OF BALE HIGHLANDS OF OROMIA REGIONAL STATE OF ETHIOPIA
    (2008-06) DEGEFA, GUTA; Dr. Hagos Ashenafi, Dr. Yacob Hailu,
    A cross sectional study comprising serological and questionnaire survey was conducted with the objective of determining the prevalence, extent and distribution of Dourine in selected horse breeding districts of Bale highlands of Oromia Regional State of Ethiopia from September 2007 to May 2008. Parasitological survey in an attempt to determine the parasitological prevalence and to isolate T. equiperdum in 71 purposively selected clinical Dourine cases revealed no trypanosomes by Giemsa staining or by Haematocrit Centrifugation Technique (HCT). A total of 880 sera were tested for the detection of antibodies against the causative agent of Dourine in four selected horse breeding districts of the Bale highlands of Ethiopia. Accordingly, the sero prevalence of Dourine was found to be 140 (15.90 %) and 173 (19.66 %) for CATT / T. evansi and LATEX / T. evansi tests, respectively. Body condition and parity number were found to have significant difference (p < 0.05) on the sero prevalence of the disease based on the CATT/ T. evansi test only. However, age, sex, history of previous abortion and castration status no significant difference (p > 0.05) on the sero prevalence of the disease using CATT/ T. evansi test. On the other hand neither of the explanatory variables had significant difference (p > 0.05) using LATEX/ T. evansi test. Logistic regression analysis revealed that horses without parity number (0) had an OR of 1.80 (1.02, 3.19) positivity compared to horses with parity number (1 and above); and horses with poor body condition (thin and very thin) had an OR of 1.44 (1.00, 2.08); positivity compared to horses with moderate body condition (less thin, less moderate and moderate) scores, on the basis of CATT/ T. evansi test. The questionnaire survey indicated that dourine is the major health problem of horses in the selected horse breeding districts of Bale highlands of Ethiopia and locally known as “Derisa” in Oromifa language and “Tigen” in Amharic language that causes high mortality and economic loss in selected horse breeding districts of Bale highlands of Ethiopia. It is a common clinical case throughout the year, however the disease has a seasonal character, which most commonly occurs whenever animals are in a good body condition and following the breeding season from April to late September and during dry season of the year (January to March), which probably associated with the relapse of previously infected and recovered cases due to the stressful condition of feed shortage. Uncontrolled breeding, unrestricted animal movement and absence of officially approved effective trypanocidal drugs against dourine cases are the main factors that play an important role in the distribution and transmission of the disease. X Even though there was no direct parasitological detection of T. equiperdum, the result of serological survey conducted by using CATT / T. evansi and LATEX / T. evansi tests together with the questionnaire survey, provides strong evidence that Dourine is highly prevalent, most important problem in selected horse breeding districts of Bale highlands of Ethiopia, where the problem of dourine is still unsolved. Further more, in view of large number of horses in Ethiopia and the unrestricted movement of animals throughout the country it is likely that dourine may be more widespread in Ethiopia than is currently realized.
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    Studies on Bovine Trypanosomosis and Efficacy of Selected Trypanocidal Drugs in Konso District, Southern Ethiopia
    (Addis Ababa University, 2008-06) Ayledo, Gewado; Ashenafi, Hagos
    Studies on bovine trypanosomosis and efficacy of selected trypanocidal drugs involving field and experimental investigations were undertaken inK onso district, southern Ethiopia, from September 2007 to April 2008, with views to determine the prevalence a nd socioeconomic impacts of bovine trypanosomosis; assess the efficacies of selected trypanocidal drugs; and evaluate the propensity of Konso community to devote public resources to integrated tsetse/trypanosomosis control approaches. Questionnaire interviews, cross-sectional and experimental study designs were applied to collect relevant information. A structured questionnaire was designed and posed to randomly selected households and key informants to identify areas with high suspicion of drug resistance. Questions addressed main issues like: herd structure and major livestock health problems; socioeconomic impacts of trypanosomosis; the sources, usage pattern and suspected failure of trypanocidal drugs, etc. Open-ended and close-ended questionnaire interviews were administered to randomly selected households to evaluate the propensity of the community to a holistic integrated disease control. In order to identify areas with high trypanosome infection pressure and risk of drug resistance, initial prevalence study was conducted in representative sample of cattle by examination of monthly blood samples through micro- haematocrit centrifugation and Buffy coat methods. The relationship between parasitological prevalence of trypanosomal infections and herd mean pev was im·estigated through haematological examination during the rainy and dry seasons. In order to assess the therapeutic and prophylactic efficacies of the common trypanocidal drugs, ten zebu calves (Bos indicus) were experimentally infected with randomly selected field isolates of T. congolensc and, when parasitaemic, treated with Diminazene aceturate and Isometamidium chloride at dose rates of 3.5 and 0.5 mglkg body weight. respectively. Experimental animals were monitored for clinical and parasitological parameters on regular basis for over three months. The study results revealed trypanosomosis to be a major threat to livestock production with contrasting arrays of socioeconomic impacts; significant reductions in cattle production losses after tsetse control and a corresponding rise in mean holdings of draft oxen and use of animal traction over the same period: an indiscriminate use and increasing tendencies in mean annual expenditure on trypanocidal drugs at the household level. Contingent valuation study disclosed animus propensity of VI integrated tsetse/trypanosomosis control; household SIze, wealth status and educational background of household heads to be the major determinants influencing willingness to support disease control. Cross-sectional study suggested an overall prevalence of 17.8 % and 14.2 % during rainy and dry season, respectively, reflecting its significant temporal and spatial variation (p< 0.001); and T congolense to be a dominant trypanosome species hampering livestock subsector in Konso district. Regression analyses on haematological findings disclosed a significant reduction (p<0.05) in the herd mean rcv with an increase in the prevalence of trypanosomosis; and that the reduction in herd rcv was significantly higher during dry season than in rainy season (p<0.001), suggesting that trypanosomosis is less-well tolerated during dry months. Results of drug sensitivity testil1g revealed the presence of T congolense populations exhibiting resistance to Diminazene aceturate and, possibly to Isometamidium chloride. In conclusion, the absence of improved veterinary service and indiscriminate use of poor-quality trypanocidal drugs have proven to boost the risk of drug resistance in Konso district. In light of the high likelihood of trypanocidal drug resistance in Ethiopia, the present findings could be a useful tool to improv~ trypanocidal drug usage strategies in the field, and could form baseline information to undertake holistic assessments of drug resistance across tsetse-infested areas of Ethiopia. It is recommendec that integrated disease control approaches be adopted with chemotherapy restricted to clinicall: sick animals, and legislations be devised and harmonized to ensure the quality of trypanocid2 drugs. Keywords: Community participation; Drug resistance; Integrated approach: Sensitivity te~ Southern Ethiopia; Livestock; T congolense; Trypanocidal drugs.
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    Studies on Bovinne Trypanoso Mosis and therapeutic Efficacy of Selected Trypanocidal Drugs in Birbir Valley of Gawo Dalle District West Oromia
    (Addis Ababa University, 2008-06) Terfa, Waktole; Hailu, Asrat
    Across Sectional Study Was Carried out to Determine the Prevalence of Bovine
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    A STUDY ON BOVINE TRYPANOSOMOSIS, TSETSE CHALLENGE AND EFFICACY OF ISOMETAMIDIUM CHLORIDE IN AMARO SPECIAL DISTRICT, SOUTHERN ETHIOPIA
    (2008-06) TESHOME, ASSEFA; Dr. Yacob Hailu, Dr. A.K. Basu; Dr. Hagos Ashenafi
    Among livestock diseases tsetse-transmitted trypanosomosis, have been incriminated as the predominant elements in the extreme deterioration of animal resources in sub-Saharan region; Ethiopia that holds the greatest potential for expanding livestock production. The part of Amaro special district particularly mid and low land is infested with tsetse fly where animal trypanosomosis is a serious threat to livestock production. Thus the objectives of the present study were: to determine the prevalence and impact of bovine trypanosomosis and seasonal density of tsetse flies; the efficacy of Isometamidium chloride on bovine trypanosomosis. The study was conducted from October 2007 to May 2008 in Amaro special district of SNNPR. The study design involved questionnaire survey, seasonal cross sectional studies of tsetse and trypanosomosis and assessment of Isometamidium chloride therapeutic efficacy. The questionnaire survey indicated that trypanosomosis is an important problem following erratic rain fall affecting the animals and impeding agricultural activity of the area. The entomological survey revealed that Glossina pallidipes species was the only prevalent species along with other biting flies (Tabanids and Stomoxys). The apparent density of flies was significantly higher in the late rainy season 1.62 fly/trap/day,2.37 and 1.6 for G. pallidipes, Tabanids and Stomoxys, respectively than the dry season where the density was 0.66, 1.12 and 1.03, respectively. The tsetse fly account 27 %, of the total fly catch Tabanids 42.6 %, and Stomoxys 29 % during late rainy season and 24.7 %, 35 %, 39.9 % during dry season. In the low lands (<1500 m.a.s.l) the apparent density for G. pallidipes was statistically significant higher (p<0.05) than the mid land areas (>1500 m.a.s.l) in both seasons. The G. pallidipes caught was higher in the bush lands vegetation type followed by grass wood land and altitudinal distribution limit was up to 1550.m.a.s.l. The apparent density of G. pallidipes fly was positively correlated (r=0.147) with prevalence of trypanosomes infection. The parasitological survey of 1136 animals (585 in the late rainy and 551 in the dry seasons) indicated trypanosomosis prevalence rate to be 27.35 % and 13.79 % in rainy and dry seasons, respectively which showed statistically significant difference (p<0.05) between seasons .The higher infection rate found in the low land areas 31.77 % and 15.45 % than the mid land areas 17.32 % and 12.68 % in the late rainy and dry season respectively indicated a statistically significant difference (p<0.05). T. congolense was the dominant species among the trypanosomes and account 61.02 % infection as compared to T. vivax 24.15 %, in the over all infections. The mean PCV value of parasitaemic and aparasitaemic animal was 21.92 % (CI=21.38-22.46) and 27.31 % (CI = 27.00-27.62) where as the over all mean values of PCV xiii was 26.23 % (CI=25.89 -26.45). The regression analysis of herd average indicated that PCV decreased with increasing prevalence of trypanosomes infections with a negative regression coefficient of values (r= -0.31) in both seasons. A statistically significant difference (p<0.05) in trypanosomes infections between different age groups of cattle was also observed. A total of 69 parasitaemic cattle were selected from 3 PAs for therapeutic efficacy of Isometamidium chloride at the dose rate of 1mg/kg bw. Parasitaemia was demonstrated in 8 out of 69 cattle (11.60 %) with in 15 days; 11out of 61 animals (18.03 %) with in 30 days; 9 out of 50 (18 %) with in 60 days and 6 out of 41 (14.63 %) cattle with in 90 days. With in 90 days of post Isometamidium chloride treatment out of 69 animals 34 (49.28 %) relapsed. In the post treatment, T. congolense contributed for 75 %, 81.82 %, 77.78 % and 66.67 % of infections with in 15, 30, 60 and 90 days, respectively. It is evidenced that trypanosomosis is one of the most important problems for agricultural and animal husbandry operations; the situation is getting worse as control and prevention of trypanosomosis is facing challenges due to limitation of vector control activities and the development of drug resistance in Amaro special district, SNNPR.
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    STUDIES ON BOVINE TRYPANOSOMOSIS AND EFFICACY OF SELECTED TRYPANOCIDAL DRUGS IN KONSO DISTRICT, SOUTHERN ETHIOPIA
    (2008-06) GEWADO, AYLEDO; Dr. Hagos Ashenafi, Dr. A.K. Basu; Dr. Yacob Hailu
    Field and experimental investigations on bovine trypanosomosis and efficacy of selected trypanocidal drugs were undertaken in Konso district, southern Ethiopia, from September 2007 to April 2008, with major views to determine the prevalence and socioeconomic impacts of bovine trypanosomosis; assess the efficacies of selected trypanocidal drugs; and evaluate the propensity of Konso community to devote public resources to integrated tsetse/trypanosomosis control approaches. Questionnaire interviews, cross-sectional and experimental study designs were applied to collect relevant information. A structured questionnaire was designed and posed to randomly selected households and key informants to identify areas with high suspicion of drug resistance. Questions addressed main issues like herd structure and major livestock health problems; socioeconomic impacts of trypanosomosis; the sources, usage pattern and suspected failure of trypanocidal drugs, etc. Open-ended and close-ended questionnaire interviews were administered to randomly selected households to evaluate the propensity of the community to a holistic, integrated disease control. In order to identify areas with high trypanosome infection pressure and risk of drug resistance, initial cross-sectional study was undertaken on randomly selected cattle heads the monthly blood samples of which were examined through micro- haematocrit centrifugation and Buffy coat methods. Linear regression model was employed to assess the relationship between parasitological prevalence of trypanosomal infections and herd average PCV. In order to assess the therapeutic and prophylactic efficacies of the common trypanocidal drugs, ten zebu calves (Bos indicus) were experimentally infected with randomly selected field isolates of T. congolense, and treated with Diminazene aceturate (3.5 mg/kg BW) when the first peak of trypanosomal parasitaemia appeared. Based on deterioration in clinical and haematological parameters, relapsed calves were re-treated with Isometamidium chloride (0.5 mg/kg BW). Experimental animals were monitored for clinical as well as parasitological parameters on regular basis for over three months. The study results revealed trypanosomosis to be a major threat to livestock production with contrasting arrays of socioeconomic impacts; significant reductions in cattle production losses after tsetse control and a corresponding rise in mean holdings of draft oxen and use of animal traction over the same period; an indiscriminate use and increasing tendencies in mean annual expenditure on trypanocidal drugs at the household level. Contingent valuation study disclosed animus propensity of Konso community to devote VII both labour and monetary resources to support integrated tsetse/trypanosomosis control; household size, wealth status and educational background of household heads to be the major determinants influencing willingness to support integrated disease control. Cross-sectional study on bovine trypanosomosis indicated an overall parasitological prevalence of 17.0 % and 13.4 % during rainy and dry season, respectively, reflecting its significant temporal and spatial variation (p< 0.001); and T. congolense to be a dominant trypanosome species hampering livestock sub-sector in Konso district. Regression analyses on haematological findings disclosed a significant reduction (p<0.05) in the herd mean PCV with an increase in the prevalence of trypanosomosis; and that the reduction in herd PCV was significantly higher during dry season than in rainy season (p<0.001), suggesting that trypanosomosis is less-well tolerated during dry months. Results of drug sensitivity testing revealed the presence of T. congolense populations exhibiting resistance to Diminazene aceturate. In conclusion, the absence of improved veterinary service and indiscriminate use of poor-quality trypanocidal drugs have proven to boost the risk of drug resistance in Konso district. In light of the high likelihood of trypanocidal drug resistance in Ethiopia, the present findings could be a useful tool to improve trypanocidal drug usage strategies in the field, and could form baseline information to undertake holistic assessments of drug resistance across tsetse-infested areas of Ethiopia. It is recommended that integrated disease control approaches be adopted with chemotherapy restricted to clinically sick animals, and legislations be devised and harmonized to ensure the quality of trypanocidal drugs.
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    Toxoplasma Gondii in Selected sites of Central Ethiopia: Seroprevalence, Risk Factors and Bioassay in Pigs
    (Addis Ababauniversity, 2014-06) Megersa, Mulisa; Dr. Ashenafi, Hagos
    The objectives of this study were to estimate the sero-prevalence of Toxoplasma gondii infection, assess potential risk factors and isolate viable T. gondii tissue cyst in mice from hearts of seropositive pigs. A cross-sectional study was used to collect blood samples from a total of 557 pigs in Central Ethiopia. A systematic random sampling technique was used for blood sample collection. For bioassay 5 mice were used per pig sample. Modified Agglutination Test (MAT) was used to test sera of pigs and mice. A questionnaire survey was made to assess potential risk factors and knowledge of farm attendants about toxoplasmosis. For investigation of risk factors questionnaire and sera samples from 402 pigs were considered. Results of the questionnaire survey indicated that most of the farm attendants had no knowledge of health risk of cats either to human or animals. Absence of rodent control, neonatal mortality and history of abortion was found among herds of the study farms. The overall estimated seroprevalence was (32.7%; 95% confidence interval (CI): 0.288-0.366). Multivariable logistic regression analysis showed that extensively managed pigs are nearly twice (adjusted odds ratio [aOR]:=1.91, 95% CI: 1.01, 3.63) at higher risk of acquiring toxoplasmosis than intensively managed pigs and pigs supplied with feed containing additional animal byproduct had four times (OR=3.84, 95% CI: 2.01, 7.36) higher risk of acquiring T. gondii infection. Viable T. gondii was isolated from 48% (24/50) of the seropositive pigs. Most isolates (91.7%, 22/24) are avirulent for mice. One isolate from Bishoftu which killed four mice on day 28 and 29 postinoculation suggesting intermediate virulence. A perfect agreement was observed between MAT and microscopic cyst detection (Kappa =0.85) used as diagnostic method on mice.This is the first report of detection of T. gondii antibodies and isolation of viable T. gondii from pigs in Ethiopia. The high seroprevalence and isolation rate indicate that T. gondii parasite is widespread in the study areas and pigs could serve as an important source of T. gondii infection for pork people. Further epidemiological studies are essential for designing appropriate prevention and control strategies in pigs. Keywords: T. gondii, sero-epidemiology, bioassay, pig, mice, Central Ethiopia
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    STUDY ON PREVALENCE OF POULTRY COCCIDIOSIS IN AND AROUND AMBO, WEST SHEWA ZONE, OROMIA REGIONAL STATE, ETHIOPIA
    (2014-06) Solomon, Shiferaw; Dr. Dinka Ayana, Dr. Waktole Terfa
    A cross sectional study was conducted on poultry coccidiosis of local and Rhode Island breed from October 2013 to February 2014 in and around Ambo town, Ethiopia. The objectives of this study were to determine the prevalence of coccidiosis, to identify species of Eimeria and to assess potential risk factors(breed,age sex and manegment system). The study involved postmortem examination of chickens, mucosal scraping and parasitological examination of oocyst, gross and histopathological examination and identification of Eimeria species. Out of 390 examined chickens 18.7%(73/390) of them were harbor different Eimeria species. Statistically no significant differences p˃0.05 (χ2=0.921, p= 0.337) was noted between young and adult age groups. Additionally there were no significant differences between local and Rhode Island Red breed(χ2= 0.16, P>0.05), management systems (extensive and semi intensive)(χ2= 2.245, P=> 0.05 and sexes(χ2= 3.609, p˃0.05). In the attempt made to identify the prevalent species of coccidian in the study area, five Eimeria species were identified, namely Eimeria. tenella, Eimeria. necatrix, Eimeria. burnette, Eimeria. maxima and Eimeria. acervulina with the prevalence of 60.27%, 15.06%, 9.6%, 1.4% and 1.4% respectively. Eimeria. tenella was the predominant species in the study area. In conclusion, the present study showed that coccidiosis is an important disease of poultry in the study area and further strategy needs to be implemented to reduce the loss due to coccidiosis.
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    TRYPANOSOMA VIVAX FROM TSETSE INFESTED AND NON-TSETSE INFESTED AREAS OF NORTHWEST ETHIOPIA: INVESTIGATION ON PATHOGENICITY AND DRUG RESISTANCE
    (2015-02) Shimelis, Dagnachew; Dr. Getachew Terefe, Prof. Bruno Maria Goddeeris; Prof. Dave Barry, Prof. Getachew Abebe
    Animal production in Ethiopia accounts for 15-17% of total Gross Domestic Product (GDP) and 35-49% of agricultural GDP. Unfortunately, the development and intensification of livestock productivity is hampered by devastating diseases, including African animal trypanosomosis. The most important trypanosomes, in terms of economic loss in domestic livestock, include: Trypanosoma vivax, T. congolense and T. b. brucei. Trypanosomes are often described as tsetse transmitted, but this is not always the case, with several species evolved for non-vector transmission or mechanical transmission by other flies. In Ethiopia, particularly the Northwest region is affected by both tsetse and non-tsetse transmitted T. vivax, with expected huge impact on livestock productivity. The control of trypanosomosis in Ethiopia relies on vector suppression and trypanocidal drugs, diminazene aceturate (DA) and isometamidium chloride (ISM) being the drugs most frequently employed. Consequently, drug resistance has become a common issue, especially for T. congolense in several areas. Although fragmented reports are available on the prevalence of the disease, attempts have not been done to demonstrate the relative importance of tsetse and non-tsetse transmitted T. vivax in terms of pathogenicity and drug resistance. This is important not only for evaluating treatment responses and to understanding host resistance/tolerance to the infections but also in the design of future vaccines and trypanocides, as well as the selection of hosts for tolerance or resistance to the parasites. Therefore, our study started with a research questionnaire survey, a prevalence study and experimental studies were conducted to assess trypanocidal drug utilization practices, estimate prevalence of trypanosomosis and the consequent pathogenesis and drug resistance status of T. vivax isolates from tsetse-infested and non-tsetse infested areas of Northwest Ethiopia. The questionnaire survey showed trypanosomosis was a significant animal health constraint for 84% (n=84) and 100% (n=100) of the farmers questioned from non-tsetse and tsetse infested areas respectively. Responses on trypanocidal drug utilization indicated that risk factors for the development of drug resistance such as frequent treatment, poor handling and administration of trypanocides are prevalent and treatment failures are common. The investigation of bovine trypanosomosis carried out in the wet season of 2011 and 2012 showed the prevalence varied from 17.59% in 2011 to 25% in 2012 in tsetse infested areas, and the difference was (P < 0.001) significant. Similarly, in non-tsetse infested areas the prevalence varied from 3.85% in 2011 to 5.93% in 2012, but in this case the rise was not significant. T. congolense (75 %) was the most prevalent species followed by T. vivax (20.58%), and mixed infections (4.41%) in tsetse infested areas while in non-tsetse infested areas only T. vivax was detected. For the investigation of pathogenicity and drug resistance against diminazene aceturate (DA) and isometamidium chloride (ISM), two consecutive experimental studies were performed on five different T. vivax isolates which we isolated from the field; three from a non-tsetse infested area and two from a tsetse infested area; in each case young Zebu cattle were experimentally infected with the isolates. Firstly one isolate from tsetse infested area (TT-ETBS1) and one isolate from non-tsetse infested area (NT-ETBD1) were tested. Secondly one isolate from tsetse infested area (TT-ETBS2) and two isolates from non-tsetse infested area (NT-ETBD2 and NT- VI – Summary ETBD3) were tested. In total 94 young Zebu cattle of which 34 for pathogenicity and 60 for drug resistance studies were used to conduct four different experiments in two consecutive experiments. Parameters measured for the investigation of pathogenicity included clinical, haematological, biochemical, cytokine, and gross and histopathological changes over the course of an infection. The result shows that both TT and NT T. vivax parasites caused clinical infection, with parasites appearing in circulation earlier in NT than TT infected cattle. The infections were characterized by reduced feed intake, intermittent pyrexia, undulating parasitaemia, rough hair coat, enlarged superficial lymph nodes, pale mucus membrane, lacrimation, emaciation and dehydration. Less frequently, diarrhea, mandibular oedema, nervous signs and recumbence were observed in both groups of infected animals. The mean packed cell volume (PCV), haemoglobin, total red blood cell and white blood cell counts were significantly lower and mean corpuscular volume (MCV) was higher in infected animals and consequently the type of anaemia observed was macrocytic normochromic in nature. The extent of changes in serum biochemical parameters, except for few cases of differences, infection with T. vivax derived from both tsetse and non-tsetse infested areas initiate similar biochemical changes indicative of significant pathology and there is no difference between parasite origins and the two experimental infections. Upon euthanasia, infected animals showed enlarged and haemorrhagic spleen; swollen and edematous lymph nodes; pneumonic and emphysematous lung; enlarged liver and haemorrhagic lesions on the brain and intestine. Histopathology revealed significant abnormalities characterized by lymphoid hyperplasia of the spleen, interstitial pneumonia, hepatic necrosis, tubulointerstitial nephritis, meningoencephalitis, and lymphoid hyperplasia in lymph nodes. With respect to the cytokine analysis, significant increases in immune cytokine (IFN-, TNF-α, IL-12 and IL-10) secretions were demonstrated in the first experiment among groups infected by both tsetse and non-tsetse T. vivax isolates, as compared with the non-infected group, but no statistical difference was observed between the groups infected with the two parasite types. However, in the second experiment, tsetse adapted T. vivax elicited a stronger immunological response than the T. vivax from the mechanically transmitted population. Concomitant with this observation is that blood parasite load remained low throughout the experimental period in the group TT compared to the NT groups. The drug resistance studies revealed that treatment of infected cattle with the recommend doses of trypanocides showed incomplete parasite clearance, consistent with the occurrence of resistant strains and adding to growing evidence that such resistance may be a problem. Furthermore at higher doses, one isolate from non-tsetse infested area (NT-ETBD2) was confirmed resistant and another one isolate (NT-ETBD3) was suspected for resistance to DA while one isolate from tsetse infersted area (TT-ETBS2) was suspected for resistance to ISM. Summary - VII Generally, T. vivax from the two locations is almost equally pathogenic, parasite appearance in blood is faster and immune cytokine responses for the most part are lower in case of NT isolate whereas trypanocidal drug resistance is prevalent in both areas. Accordingly the following recommendations are forwarded; a) The present findings, reminded us that the impact of T. vivax should not be neglected in both tsetse and non-tsetse infested areas, b) Frequent administration, poor utilization and handling of trypanocidals could be sources of the problem for drug resistance and hence, appropriate corrective measures be taken in both tsetse and non-tsetse infested areas. In addition, further studies on the mechanisms of resistance for T. vivax is essential to monitor drug resistance and identify potential targets for new drugs, c) The early appearance of parasites in blood and lower cytokine responses in non-tsetse T. vivax infected groups needs further investigation from the parasite, vector and host angles.
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    STUDY ON IN VITRO LOUSCIDAL AND ACARICIDAL PROPERTIES OF CALPURNIA AUREA, OTOSTEGIA INTEGRIFOLIA, NICOTIANA TABACCUM AND JATROPHA CURCAS AGAINST BOVICOLA OVIS AND AMBLYOMMA VARIEGATUM
    (2015-06) Sisay, Alemu; Dr. Yacob Hailu, Dr. Getachew Terefe; Dr. Mirutse Giday; Dr. Ahmed Yasin
    The present study was designed to evaluate the preliminary phytochemicals present in methanolic leaf extracts of Calpurnia aurea, Otostegia integrifolia, Nicotiana tabaccum and petroleum ether seed oil extract of Jatropha curcas and to assess their in vitro louscidal and accaricidal efficacy. Accordingly, each plant was subjected to qualitative phytochemical screening for the presence or absence of secondary metabolites such as alkaloids, steroidal compounds, phenolic compounds, flavonoids, saponins, tannins, phlobatannins, triterpens and glycosides using standard procedures. The four selected medicinal plants and a commercially used acaricide (0.1% diazinon) were examined for their louscidal and acaricidal activity against B. ovis and A. variegatum at different time intervals using the in vitro adult immersion test at concentrations of 200, 100, 50, 25, 12.5 and 6.25 mg/ml. The findings revealed that extracts of C. aurea leaf and J. curcas seed oil caused high mortalities of B. ovis at all concentrations with no significant difference from the activity of 0.1% diazinon ( > 0.05) within 24 hours of exposure. Moreover, at 200 mg/ml concentration, crude extracts of N. tabaccum and O. integrifolia produced 93% and 63% mortality respectively against B. ovis within 24 hours of exposure. The extracts of all four plants were also examined for their acaricidal activity against A. vareigatum. Although, the effects of the extracts on this tick species was much lower than what was observed on lice, the extracts of C. aurea leaf and J. curcas seed oil have shown 56% and 39% mortality at 200 and 100 mg/ml concentrations, respectively within 24 hrs exposure of the parasite and was comparable to the acaricidal activity of 0.1% diazinon ( > 0.05). A similar situation was caused by crude extracts of N. tabaccum which was 44% and 39% mortality at concentrations of 200 and 100 mg/ml within 24 hrs of exposure, respectively. However, O. integrifolia showed significantly lower acaricidal activity ( < 0.05) when compared to the reference drug (0.1% diazinon). The current study revealed that crude extracts of C. aurea leaf and J. curcas seed oil have strong louscidal activity. Moreover, crude extracts C. aurea and J. curcas showed high mortality at lower concentrations and can be used as a potential alternative to synthetic acaricides to control B. ovis infestations. Though, they are not effective at lower concentrations, crude extracts of C. aurea, N. tabaccum and J. curcas seed oil had better acaricidal effects on cattle ticks at higher concentrations. This is a promising finding to have an alternative means of treatment to substitute the use of synthetic drugs which have a widespread drug resistance especially in developing countries including Ethiopia. xiv Therefore, further investigation should be made on their safety and in vivo efficacy as well as cost effectiveness of the products that exhibited strong louscidal and acaricidal activity with a view of substituting the conventional synthetic acaricides.
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    Pathological and Seroprevalence Studies on infectious Bursal Disease in Chickens In and Around Bahir Dar, North west, Ethiopia
    (Addis Ababauniversity, 2015-06) Teshager, Natnael; Dr. Ashenafi, Hagos
    A cross sectional study was conducted from January 2015 to May 2015 to characterize the pathological changes and to determine seroprevalence of IBD and its associated risk factors in chickens in and around Bahir Dar. The clinical signs observed in IBD infected chickens were whitish diarrhea mixed with blood, ruffled feather, and massive death within short period. The necropsy findings were petichial hemorrhage in bursa of fabricius, kidney, thymus, spleen, thigh and pectoral muscles. Bursa of fabricius became edematous in serosa and mucosal part, whitish-creamy and atrophied as the course of the disease progressed. Kidney became pale and ureter was turgid with urate in a numbers of cases. The histopathological changes in this study revealed that edema of bursa of fabricius, formation of cystic follicles, depletion of lymphocytes, fibrosis and follicular architecture lost. Severe, moderate and mild lesion score were observed in bursa of fabricius. Infiltrations of heterophils were noted both in lymphoid and non lymphoid tissues. Depletion of lymphoid cell in germinal center of spleen and total depletion of lymphoid cells were encountered in thymus gland. The kidney tubules were filled by exudates and necrotized cuboidal cells. Sera collected from a total of 320 chickens were subjected to IELISA test and disclosed an overall prevalence of 51.56% (CI: 45.95 – 57.14) in study area. The seroprevalence of IBD among chickens showed a statistically significant difference (P<0.05) among study sites namely Andassa (72.73%), Gombat (50%), Wonjeta (47.69%), Meshenty (44.44%) and Bahir Dar (42.42%). The susceptibility of chickens to IBDV revealed a statistically significant difference (P<0.05) among different breeds where Koekoek was found more prone to IBD infection with seroprevalence of 67.11% followed by Bovans brown (57.69%), local breeds (48.31%), and Bovans white (40.28%). The seroprevalence of IBD was also significantly associated (P<0.05) with the age of chickens and among farm systems. These studies clearly indicated that IBD infection is a common and wide spread problem affecting a number of chicken breeds under different management systems and hence an urgent control intervention should be in place. Keywords: Age, Bahir Dar, Breed, Chickens, Histopathology, Lesions, Seroprevalence, sex
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    In Vitro Effecacy of Methanolic Extracts of Vernonia Amygdalina, Croton macrostachyus, Ricinus Communis and Petroleum Ether Extract of Millettia Ferruginea against Bovicola ovis and Rhipicephalus (Boophilus) Decoloratus
    (Addis Ababauniversity, 2015-06) Gizaw, Askale; Dr. Giro, Bulto
    In vitro loucicidal and accaricidal efficacy evaluation of Vernonia amygdalina, Croton macrostachyus, Ricinus communis and Millettia ferruginea against Bovicola ovis and Rhipicephalus decoloratus of cattle were carried out from January 2014 to April 2015. Crude methanol extracts of Vernonia amygdalina, Croton macrostachyus, Ricinus communis leaf and Petroleum ether extract of Millettia ferruginea seed oil were prepared for in vitro test at different time intervals. The four selected medicinal plants, at concentrations of 200, 100, 50, 25, 12.5 and 6.25mg/ml and a commercially used acaricide (0.1% diazinon), were examined using in vitro adult immersion test. In vitro loucicidal test showed all concentration of Millettia ferruginea oil (μl/ml), ≥25mg /ml concentration of Croton macrostachyus and 200 and 100mg/ml concentration of Ricinus communis had pronounced loucidal activity at 24hr of exposure. 200mg/ml concentration of Vernonia amygdalina and ≤6.25mg/ml concentration of Croton macr ostachyus had moderate loucicidal activity at 24hr of exposure. Moreover, the 200 and 100μl/ml concentration of Millettia ferruginea seed oil and 200mg/ml concentration of Ricinus communis leaf crude extract had high accaricidal activity (90-100%) against Rhipicephalus decoloratus while crude methanolic extracts of Croton macrostachyus and Vernonia amygdalina and even the positive control (diazinon) showed low acaricidal activity (<35%) against the tick species. All plants had significantly (P< 0.05) higher activity against lice than Rhipicephalus decoloratus ticks except Millettia ferruginea at (200 and 100μl/ml) and Ricinus communis (at 200 mg/ml) which showed both accaricidal and loucicidal activity. Therefore the present study concluded that Croton macrostachyus, Ricinus communis and Millettia ferruginea against Bovicola ovis whereas Ricinus communis and Millettia ferruginea against Rhipicephalus decoloratus could be used as potential alternative in the discovery of guide compounds that substitute commercially available acaricides. In addition, the low activity of diazinon on ticks compared to our plant extracts deserves further attention. Key Words: Acaricide, Bovicola ovis, in vitro, loucicide, medicinal plants, Rhipicephalus decoloratus