In Vitro Acaricidal Activity of Selected Medicinal Plants Traditionally Used against Ticks in Eastern Ethiopia.

A study was carried out to evaluate the acaricidal activities of crude methanolic extract of leaves of six medicinal plants, namely, Vernonia amygdalina, Calpurnia aurea, Schinus molle, Ricinus communis, Croton macrostachyus, and Nicotiana tabacum, against Rhipicephalus (Boophilus) decoloratus and Rhipicephalus pulchellus using an in vitro adult immersion test. Five graded concentrations of the crude extracts, 6.25, 12.5, 25, 50, and 100 mg/ml, were tested at different time intervals, and temporal changes in tick viability were recorded for 24 hours. Diazinon (0.1%) and distilled water were used as positive and negative controls, respectively. Standard procedures were applied to screen the phytochemical constituents of the tested plant parts. Phytochemical screening showed the presence of a condensed amount of tannins in all extracts. Starting from 30 min post exposure, the 100 mg/ml concentration of C. aurea and R. communis extracts has caused significantly higher mortality (P < 0.05) compared to the diazinon. A significant increase in tick mortality started 2 hr post exposure with diazinon and 50 and 100 mg/ml concentrations of S. molle. Vernonia amygdalina extract and diazinon showed a significant increase in tick mortality 3 hr post exposure with 100 mg/ml concentration. Similarly, a significant increase in tick mortality started 2 hr post exposure with diazinon and 100 mg/ml concentrations of C. macrostachyus and N. tabacum. At 24 hr post exposure, diazinon and 50 and 100 mg/ml concentrations of all the extracts have caused significantly higher tick mortality than the rest of the concentrations (P < 0.05). Higher concentrations of all the extracts had showed a comparable and strong acaricidal effect on Rhipicephalus (Boophilus) decoloratus and Rhipicephalus pulchellus having no significant difference with that of the positive control (P > 0.05) at 24 hr post exposure period. Tick killing activity of all evaluated plant extracts increases with increasing exposure time and concentration as well. Thus, all the tested plants could be used against Rhipicephalus (Boophilus) decoloratus and Rhipicephalus pulchellus as a potential alternative to substitute commercially available drugs. We recommend further study on fractionating each component separately and validating the materials.

Bovine tuberculosis in eastern Ethiopia: prevalence, risk factors and its public health importance.

BACKGROUND: Bovine tuberculosis is among the primary zoonotic disease caused by Mycobacterium bovis which has significant impact on the health of livestock and human. It has been significantly a cause for great economic loss in animal production. METHODOLOGY: A cross-sectional study was conducted from December 2014 to June 2016 on 315 cattle in selected areas of eastern Ethiopia, aiming to estimate the occurrence of bovine tuberculosis using comparative intradermal tuberculin skin test and assess cattle owners' awareness on its public health implication. Random sampling method was applied in order to select animals from farm/household and associated risk factors were recorded before purified protein derivative (PPD) injection. Forty three farm/household owners of tuberculin tested animals were interviewed using pre-tested structured questionnaires. RESULTS: The overall prevalence of bovine tuberculosis was 20.3% (n = 64) in dairy cattle at recommended cut off > 4 mm. From a total of 43 farms/households tested, 22 were positive; each farm exhibited at least one tuberculin positive reactor animal with a total herd level prevalence of 51.2%. The prevalence of bovine tuberculosis in individual animal level was significantly different (χ2 = 45.2; P-value = 0.000) in different sites with a higher prevalence (50%) in Dire Dawa. Farming system, herd size and other risk factors were significantly (p < 0.05) associated with bovine tuberculosis occurrence. Of the total interviewed farm owners, only 33% had the knowledge of or had heard about bovine tuberculosis and 23% respondents were aware of the zoonotic importance of the disease. More than 50% of the interviewees had shown their preference of raw milk consumption. Out of the total interviewed households, 3 (7%) farm workers had TB cases that had direct contact with the animals. CONCLUSION: The study showed bovine tuberculosis is highly prevalent. Associated risk factors contributed to the prevalence of the disease in cattle and its transmission. Moreover, the majority of cattle owners lack awareness about the disease and its public health significance. Awareness rising about the disease, its transmission and zoonotic implication is of great importance for reduction and control measures. Evidence of tuberculosis patient farm attendants calls also for further detail investigation.

Cloacael Carriage and Multidrug Resistance Escherichia coli O157:H7 from Poultry Farms, Eastern Ethiopia.

A cross-sectional study was carried out to determine antimicrobial drug resistance patterns of E. coli O157:H7 isolates and estimate the level of the pathogen. A total of 194 cloacae swab samples were collected randomly in two poultry farms. Standard cultural, biochemical, and serological (latex agglutination) methods were used to isolate E. coli O157:H7. The isolates were subjected to antimicrobial susceptibility testing using disc diffusion method. Out of 194 cloacae samples examined, 13.4% (n = 26) were found to be positive for E. coli O157:H7. The finding indicated differences in E. coli O157:H7 infection among the different risk factors. Chicken from Adele Poultry Farm showed higher E. coli O157:H7 infection (OR = 3.89) than Haramaya University poultry farm and young birds had more infection (OR = 4.62) than adult birds. Of the total 14 antimicrobials included in the panel of study, the susceptibility results were varied with 96.15% and 0% E. coli O157:H7 isolates expressing resistance to erythromycin, clindamycin, spectinomycin, and ciprofloxacin, respectively. Multidrug resistance to more than two antimicrobial agents was detected in 24 (92.30%) of the isolates. The study showed high presence of antimicrobial resistant isolates of E. coli O157:H7. Further study is required to better understand the ecology and evolution of bacterial resistance to antimicrobial agents.

Prevalence, assessment, and antimicrobial resistance patterns of Salmonella from raw chicken eggs in Haramaya, Ethiopia.

INTRODUCTION: The presence of antimicrobial-resistant Salmonella in poultry and poultry products, including eggs, is a global public health concern. This study aimed to estimate the levels and patterns of antimicrobial resistance of Salmonella from chicken eggs and assess consumers' raw egg consumption and farmers' handling practices. METHODOLOGY: A total of 300 egg samples were collected from Haramaya open market (n = 150) and Haramaya University poultry farm (n = 150) in Ethiopia. Questionnaires were administered to egg sellers and buyers. A sterile cotton swab was used to sample the surface of eggs. The shells were sterilized and the egg content sampled. Isolation was done using the conventional methods for the detection of Salmonella, following the standard guidelines from ISO 6579. Sensitivity to 12 selected antibiotics was tested following the procedure of the Clinical and Laboratory Standards Institute. RESULTS: A level of 5.3% was observed among eggs shells from the open market and 0% among egg shells from the poultry farm, for an overall level of 2.7%. There was a significant difference (p = 0.004) between the prevalence of Salmonella spp. in sample site and sample type. Of the antimicrobials tested, Salmonella isolates were all resistant to erythromycin and clindamycin. Isolates were sensitive to ciprofloxacin (100%) and chloramphenicol (87.5%). All isolates were resistant to multiple antibiotics. One-third of the consumers were found to have eaten raw eggs for perceived medicinal values. CONCLUSION: To minimize the potential contamination of eggs by pathogens, the eggs should be properly handled, transported, and stored.

Isolation, Identification, and Antibiotic Susceptibility Testing of Salmonella from Slaughtered Bovines and Ovines in Addis Ababa Abattoir Enterprise, Ethiopia: A Cross-Sectional Study.

Salmonellae are ubiquitous, found in animals, humans, and the environment, a condition which facilitates transmission and cross contamination. Salmonella enterica serotypes exert huge health and economic impacts due to their virulence or carriage of antibiotic resistance traits. To address this significant issues with regard to public health, availability of adequate information on the prevalence and antibiotic resistance patterns of Salmonella, and establishment of adequate measures to control contamination and infection are needed. A cross-sectional study was conducted to assess the level of Salmonella infection in slaughtered bovines and ovines at Addis Ababa abattoir. Samples were collected randomly and processed for identification and antimicrobial susceptibility testing of Salmonella spp. From 280 animals examined, 13 (4.64%) (8 bovines and 5 ovines) were positive, with most samples (12/13, 92%) comprising Salmonella Dublin. Very high level of resistance to some antibiotics used in human medicine was detected. Most isolates were susceptible to gentamycin and amikacin. Nine (69%) of all isolates were resistant to multiple antibiotics. Serotyping revealed 12 of 13 isolates to be of the Dublin serotype with 9,12:g,p:- antigenic formula. This study emphasizes the importance of improving the evisceration practice during slaughtering and restricting the use of antibiotics in farm animals.

Infestation and Identification of Ixodid Tick in Cattle: The Case of Arbegona District, Southern Ethiopia.

The study was conducted from October 2014 to June 2015 to estimate tick prevalence and identify major tick genera infesting cattle and the associated risk factors in Arbegona district, southern Ethiopia. A total of 2024 adult ticks were collected from main body parts of animals and eight species of ticks which belong to three genera were identified. Questionnaire survey was employed concerning the general case on the tick infestation problems on the cattle. From 384 cattle examined, 291 (75.7%) were found to be infested with one or more types of tick species. The relative prevalence of each genera was Amblyomma (34.9%), Rhipicephalus (Boophilus) (26.6%), Hyalomma (19.2%), and Rhipicephalus (19%). The prevalence of tick infestation in good (65.5%), medium (74%), and poor body condition animal (100%) was found to be statistically significant (p < 0.05). There was also significantly (p < 0.05) higher prevalence in old (98.4%) than adult (78.8%) and young (59.8%) age groups of animals. In the survey, 87.5% of respondents believe that there was tick infestation problem in their locality. This study showed there was high burden and prevalence of ticks that still play major roles in reducing productivity and cause health problems of cattle in the area which call for urgent attention.