Incidence of uterine infections, major bacteria and antimicrobial resistance in postpartum dairy cows in southern Ethiopia.

BACKGROUND: Uterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and economic losses. However, the bacteria responsible for uterine infections have not been adequately studied, nor has the antibiotic susceptibility of the causative bacteria been frequently tested in Ethiopia. This study aims to estimate the cumulative incidence of uterine infections in postpartum dairy cows, identify bacterial causes and determine antimicrobial susceptibility profile of the isolated bacteria. METHODS: A prospective cohort study was conducted in which 236 cows from 74 dairy farms were monitored biweekly from calving to 90 days postpartum for metritis, endometritis and other disorders. Aseptic uterine swab samples were collected from 40 cows with uterine infections. The samples were cultured, and the isolated bacteria were tested for antimicrobial susceptibility using the disk diffusion method. RESULTS: Out of 236 cows monitored during the postpartum phase, 45 (19.1%) were found to have contracted uterine infection. The cumulative incidence of metritis was 11.4% (n = 27), while the cumulative incidence of endometritis was 7.6% (n = 18). Of the 40 cultured swab samples, 29 (72.5%) had one or more bacteria isolated. The most commonly isolated bacteria were Escherichia coli (45%), coagulase-positive staphylococci (30%), and Klebsiella spp. (22.5%). Other bacterial spp, including Arcanobacterium pyogenes (12.5%), Fusobacterium spp. (12.5%), Enterobacter aerogenes (12.5%), coagulase-negative staphylococci (12.5%), Streptococcus spp. (7.5%), Salmonella spp, (5%) Proteus spp (5%) and Pasteurella spp (2.5%) were also isolated. All of the isolated bacteria demonstrated resistance to at least one of the antimicrobials tested. Multidrug resistance was observed in E. coli, Klebsiella spp., A. pyogenes, and Fusobacterium spp. Gentamicin was found to be the most effective antimicrobial against all bacteria tested, while tetracycline was the least effective of all. CONCLUSION: The study found that a significant proportion of cows in the population were affected by uterine infections and the isolated bacteria developed resistance to several antimicrobials. The study emphasizes the need for responsible use of antimicrobials to prevent the emergence of antimicrobial resistance. It also highlights the importance of raising awareness among dairy farmers to avoid the indiscriminate use of antibiotics and its consequences.

Incidence rate, risk factors, and bacterial causes of clinical mastitis on dairy farms in Hawassa City, southern Ethiopia.

Mastitis is the most common disease of dairy cattle worldwide, causing economic losses due to reduced yield and poor quality of milk. It is of particular concern in Ethiopia, where effective prevention and control practices are lacking. The objective of the present prospective longitudinal study was to estimate the incidence rate of clinical mastitis (CM), identify the risk factors, isolate the bacterial agents, and determine the risk of recurrence. For this purpose, a total of 217 lactating cows were followed up every two weeks from calving to drying off or the end of the study period. Of these, 79 (36.41%) developed CM, of which 23% had recurrent infections in the same or a different quarter. The overall incidence rate of CM was 83.72 (95% CI: 63.2-98.2) cases per 100 cow-years at risk. In the multivariable Cox regression model, the risk of CM was found to be significantly higher in multiparous cows (HR = 1.96; p = 0.03), in cows with a history of mastitis (HR = 2.04; p = 0.030), in cows that had severely keratinized teat end condition (HR = 7.72; p < 0.001) and in cows kept in poorly cleaned barns (HR = 1.89; p = 0.007). The pathogenic bacteria isolated from mastitis-positive cows were Staphylococcus aureus (28.1%), E. coli (21.1%), Bacillus spp. (14%), Streptococcus spp. (14%), coagulase-negative staphylococci (12.3%), non aureus staphylococci (5.3%), Enterobacter spp. (3.5%), Klebsiella spp. (1.8%), Corynebacterium spp. (1.8%), and Proteus spp. (1.8%). The high incidence rate of CM in the present study shows that the disease spreads rapidly and can be responsible for a significant economic loss to milk producers in the study area. Therefore, raising awareness among dairy farmers, early detection and treatment of cases, post-milking teat disinfection, improvement of the hygienic status of cows and barns, use of dry cow therapy, and culling of chronic cases are recommended as viable measures to prevent and control clinical mastitis in the study area.

Longitudinal study of calf morbidity and mortality and the associated risk factors on urban and peri-urban dairy farms in southern Ethiopia.

BACKGROUND: Calf morbidity and mortality are among the leading causes of economic losses on dairy farms around the world. Poor calf management practices exacerbate the problem in developing countries like Ethiopia. This prospective, longitudinal study was conducted on 70 selected dairy farms in southern Ethiopia with the aim of estimating calf morbidity and mortality rates, identifying the associated risk factors and determining whether the mortality rate is above economically tolerable levels. For this purpose, a total of 274 calves on 70 farms were followed up every two weeks from birth to six months of age for major clinical health problems and deaths. RESULTS: The study found a morbidity rate of 13.2 cases and a mortality rate of 3.8 cases per 100 calf-months at risk in the study calves. The cumulative incidence of morbidity and mortality was also found to be 40.29% and 12.85%, respectively. Diarrhea was the leading cause of morbidity and mortality in calves, accounting for 71.3% and 62.1% of all morbidity and mortality, respectively. In a multivariable Cox regression analysis, the risk of morbidity was significantly (p = 0.022) higher in calves born to dystocia-affected dams (HR = 2.4) and on farms where dairy farming is the farmers' secondary source of income (HR = 1.7). However, the risk of morbidity was significantly (p < 0.001) lower in calves older than three months (HR = 0.22), female calves (HR = 0.57), calves raised by farmers who had completed secondary school (HR = 0.26) or college education (HR = 0.30). Similarly, calves aged over three months (HR = 0.14), calves separated from their dams only after ingestion of colostrum (HR = 0.40) and calves owned by farmers who completed secondary school (HR = 0.08) or college education (HR = 0.13) all had lower mortality rates than other groups. On the other hand, calves born to cows with dystocia were 5.2 times more likely to die. CONCLUSION: The study concluded that calf morbidity and mortality rates in the study area are higher than economically tolerable levels and therefore it is recommended to raise awareness among farmers to improve calf management practices.

Isolation, molecular detection and antimicrobial susceptibility profile of Salmonella from raw cow milk collected from dairy farms and households in southern Ethiopia.

BACKGROUND: Salmonella is one of the foodborne pathogens affecting public health around the globe. A cross-sectional bacteriological study was conducted from December 2019 to November 2020. This study aimed to isolate, molecularly detect and determine antibiotic susceptibility patterns of Salmonella from raw cows' milk collected from dairy farms and households in Hawassa, Arsi Negele, and Dale districts. MATERIALS AND METHODS: A total of 384 raw milk samples were collected using a simple random sampling technique. Standard bacteriological and biochemical tests were used to isolate Salmonella. The positive samples were further confirmed by the molecular test. Kirby-Bauer disk diffusion method was used for antimicrobial susceptibility testing of Salmonella. RESULTS: Using bacteriological and biochemical detection tests, Salmonella was isolated from 10.42% (N = 40) of the total sample. However, in molecular detection, only 32 of the 40 isolates were confirmed to be Salmonella using PCR test. The prevalence was 8.54, 12.69, and 10.46% in Hawassa, Dale, and Arsi Negele districts, respectively. Bacteriological prevalence did not vary significantly between the districts (P > 0.05). Likewise, no significant (P > 0.05) variation was observed in the Salmonella isolation rate between households (12.5%) and farms (8.33%) as well as between dry (8.85%) and wet (11.98%) seasons. Based on herd size, the isolation rate of Salmonella was significantly higher (P < 0.05) in large-scale farms (19.51%) than in small (5.1%) or medium (5.6%) scale dairy farms. The result of the antibiotic susceptibility test showed that Salmonella isolates were 100% resistant to ampicillin, while they were 100% sensitive to ciprofloxacin. Multi-drug resistance (MDR) was demonstrated in all isolates. CONCLUSION: This study showed that Salmonella is widespread in the raw milk samples and developing MDR, which may be of public health concern in the study area. It is therefore important that dairy farmers and raw milk sellers in the study area take serious measures to avoid contamination of the milk with Salmonella spp. In addition, the active commitment of the animal health departments in the respective districts to sensitizing dairy farmers and the sensible use of antibiotics at the farm level can help to reduce the antibiotic resistance of Salmonella spp.

Incidence of morbidity and mortality in calves from birth to six months of age and associated risk factors on dairy farms in Hawassa city, southern Ethiopia.

Calf morbidity and mortality are major causes of economic losses on dairy farms worldwide, with a far greater impact in developing countries such as Ethiopia. A prospective longitudinal study on dairy farms in the city of Hawassa was conducted between August 2018 and July 2019, to estimate the cumulative incidence of calf morbidity and mortality and to identify the associated risk factors. For this purpose, 221 calves from 20 farms were examined every 15 days from birth to the age of six months. We used the Kaplan Meier (K-M) method, log rank test, and Cox proportional hazards regression to analyze the data. Of the calves examined, 48.4% (n = 107) had various clinically visible health problems, while 19.5% (n = 43) died from various causes. Using the K-M method, the cumulative incidence of all-cause morbidity at the end of the sixth month of life was 50.12% (95% CI: 43.58%-57.05%), while the cumulative incidence of all-cause mortality was 20.04% (95% CI: 12.56%-26.06%). The most commonly diagnosed disease syndrome was diarrhea (64.5%), followed by pneumonia (15%), septicemia (6.5%), joint disease (4.7%), conjunctivitis (3.7%), umbilical infections (2, 8%) and other unknown causes (11.2%). Diarrhea was also the leading cause of death (46.5%). The other causes of calf mortality were pneumonia (16.3%), septicemia (7%), and unknown diseases (30.2%). In the K-M hazard analysis, the greatest risk of calf morbidity and mortality was observed during the first month of life and then the risk decreased significantly as the calves grew. Of the 21 potential risk factors studied, the multivariable Cox proportional hazards regression model showed that time calves ingested their first colostrum, calving difficulty, and calving season were the three predictors that were significantly associated with a higher risk of morbidity and mortality. A higher risk of morbidity was observed in calves that had ingested their first colostrum six hours after birth (HR = 1.9; P = 0.003), had calving difficulties (HR = 2.96; P < 0.001) and were born in the rainy season (HR = 1.64; P = 0.017) compared to calves that had consumed colostrum immediately after birth, had no difficulties at birth and were born in the dry season. The same three factors have been identified to influence calf mortality. The mortality risk was 2.73 (P = 0.002), 4.62 (P < 0.001) and 2.74 (P = 0.002) times higher in calves that had difficulty calving, ingested their first colostrum meal six hours after birth and were born in the rainy season, respectively. In general, the calf morbidity and mortality rates identified in this study were beyond economically justifiable limits and calls for educating farmers to raise awareness of some easy-to-fix issues such as colostrum feeding.

Prevalence of bovine trypanosomosis and vector density in a dry season in Gamo-Gofa and Dawuro Zones, Southern Ethiopia.

Trypanosomosis remains one of the biggest constraints of livestock productivity in sub-Saharan Africa. It is of particular concern in Ethiopia where crop production is largely dependent on animal traction power. This study was conducted between November 2015 and March 2016 to estimate the prevalence of bovine trypanosomosis and vector density in Gamo-Gofa and Dawuro Zones located in Southern Ethiopia. For the entomological survey, a total of 305 NGU traps were deployed for three consecutive days at different positions in the two study areas. For parasitological study, blood samples were collected from 2402 cattle and examined for the presence of trypanosomes by the buffy coat technique (BCT). Blood samples that were positive in the BCT were further tested with Giemsa-stained thin smears for identification of Trypanosoma species. In the entomological survey, a total of 4113 flies were captured of which 1605 (39%) were tsetse flies while 2508 (61%) were other biting flies of the genus Stomoxys and Tabanus. Glossina pallidipes was the only tsetse fly identified in the study areas. The overall mean apparent density of G. pallidipes was 1.8 flies per trap per day (FTD). The overall prevalence of trypanosomosis in the study areas was 5.1% (95% CI: 4.2-6.0); however, it was significantly (p < 0.001) higher in Dawuro Zone (10%) than Gamo-Gofa (1.9%). Prevalence was also noted to be significantly (p < 0.001) higher in cattle with black coat colour and those with poor body condition. Trypanosomosis was caused mainly by Trypanosoma congolense (61.8%) and to a lesser extent by T. vivax (28.5%). Mixed infection by the two spp. was seen in 9.8% of the total positive animals. Evaluation of the mean packed cell volume (PCV) of the study animals with infection status revealed a significantly (p < 0.001) lower mean PCV in parasitaemic animals (21.5 ±â€¯0.46SE) than aparasitaemic ones (24.3 ±â€¯0.11SE). Generally, the prevalence noted in the current study is moderate. However the observation of such level of infection in a dry season suggests that the disease is still an important constraint of cattle production in the study areas. Thus, we recommend that theexisting parasite and vector control interventions need to be strengthened with special emphasis to Dawuro Zone where the prevalence was significantly higher. As the current sampling was done only once and in a dry season only, further longitudinal studies including all the seasons of the year need to be considered in the future.

Muscular Sarcocystis infection in ruminants slaughtered at Municipality abattoir and selected Hotels in Hawassa city, southern Ethiopia: Prevalence and associated risk factors.

Sarcocystosis is a parasitic zoonosis caused by Sarcocystis spp. which are Apicomplexan parasites requiring intermediate and definitive hosts to complete their life cycle. Although the parasite has worldwide distribution in man and many species of animals, the prevalence in most parts of Ethiopia is not clearly known. This cross sectional study was conducted between Nov. 2016 and May 2017 to estimate the prevalence of Sarcocystis infection in ruminants slaughtered in the municipality abattoir and at selected hotels of Hawassa city and to assess the potential risk factors. Data were collected through gross and histopathological examination of myocardial and esophageal muscles sampled from a total of 561 ruminants (176 sheep, 181 goats and 204 cattle). The overall prevalence of Sarcocystis infection in ruminants was 68.98%. All of the cysts were microscopic, and found more frequently (p < .05) in heart (62.08%) than esophageal muscle (45.45%) although concurrent infection of both organs was observed in 33.87% of the ruminants examined. No significant association was noted between Sarcocystis infection and the origin, sex and species of ruminants examined (p > .05). The higher prevalence recorded in the study area can be explained by the abundance of stray dogs, cats and wild carnivores that are roaming in the villages, lack of proper latrine, uncontrolled disposal of condemned offals and carcass, and provision of uncooked meat for dogs and cats. Thus, farmers' awareness creation and strategies targeted at breaking the life cycle of the parasite are required to reduce the prevalence of the parasite and thereby the foreseen zoonotic and economic impact.

Prevalence of Pneumonia in Sheep and Goats Slaughtered at Elfora Bishoftu Export Abattoir, Ethiopia: A Pathological Investigation.

Accurate clinical diagnosis of pneumonia, the leading cause of mortality in small ruminants, is difficult and usually requires postmortem examination of the lungs. An active abattoir survey was conducted between November 2017 and April 2018 to estimate the prevalence and characterize the gross and histopathological lesions of pneumonic lungs in 864 clinically healthy young small ruminants (490 sheep and 374 goats aged 1.5 to 3 years) raised for meat in different parts of the country and slaughtered at Elfora Bishoftu export abattoir, Ethiopia. Out of the total lungs examined grossly, pneumonic lesions were found in 158 (18.29%) lungs. On histopathological examination of the lungs with gross pneumonic lesion, however, typical pneumonic lesions were diagnosed in 148 (17.13%) lungs only. No significant (p>0.05) difference was noted in the prevalence of pneumonia between sheep (17.14%) and goats (17.11%) in histopathological examination. Based on the predominant histopathological findings, the pneumonic lesions were characterized as interstitial pneumonia (41.9%), acute suppurative bronchopneumonia (25.7%), acute fibrinous bronchopneumonia (24.3%), chronic bronchopneumonia (6.1%), aspiration pneumonia (4.7%), bronchointerstitial pneumonia (3.4%), and ovine pulmonary adenomatosis (3.4%). The study further showed the spread of ovine pulmonary adenomatosis and ovine progressive pneumonia (Maedi) from the central highlands to areas that were previously free from these diseases. Due to its better diagnostic capacity, histopathology should be employed routinely as an ancillary test in the major abattoirs and regional veterinary laboratories to generate additional epidemiological data for a better disease control and prevention measures. Further studies are also recommended to identify the etiological agents of pneumonia in sheep and goats and thereby to formulate feasible and cost-effective interventions.

Lungworm infection in small ruminants in Ethiopia: Systematic review and meta-analysis.

Lungworms are important parasitic nematodes of small ruminants that colonize the lower respiratory tract and cause high morbidity and economic loss throughout the world. This systematic review was conducted with the aim of estimating the pooled prevalence of lungworm infection in small ruminants in Ethiopia. Besides, it examines the predictors thought to be responsible for heterogeneity noted between the reports. The search databases used were PubMed, CAB direct, AJOL and Web of science. Eligible studies were selected based on predefined inclusion and exclusion criteria. Thirty two studies published between 2000 and 2016 were found eligible and data were generated on 14,257 small ruminants (12,310 sheep and 1947 goats). Predictors including the study area, type of small ruminants affected, parasitic species involved, a diagnostic test used, study design, management systems, breed, agroecology, and year article published were used as milestone of data extraction. The statistical tool employed were meta-analysis, univariable and multivariable meta-regression and Egger's and begg's statistics for sensitivity analysis. Accordingly, the estimated pooled prevalence of lung worm infection in small ruminants was 40.8% (95% CI: 36.1, 45.6) with a very high heterogeneity between the study reports (I2 = 96.5%). However, diagnostic test used and administrative States were the only two predictors identified to explain 15.5% of the explainable heterogeneity (R2 = 0.1545, tau2 unexplained = 0.6032, tau2 total = 0.7135) noted between studies. The reviewed studies showed that three genera of lungworms, namely Dictyocaulus filaria, Mullerius capillaris and Protostrogylus rufescens were prevalent both in sheep and goats in Ethiopia. Mixed infection with two or three species was reported in 4.4 to 48.6% of the total infected animals. Indeed this review is informative and provides a better picture on lungworm infection in Ethiopia; however, it is not exhaustively detailed as there was lack of clear data on the role of some important factors like age, flock size, management system and seasonal variation on lungworm infection. Thus, thorough epidemiological studies including all seasons are required for formulation of meaning full control strategies.

Bovine trypanosomosis and vector density in Omo-Ghibe tsetse belt, South Ethiopia.

African animal trypanosomosis (AAT) is a parasitic disease that causes serious economic losses in livestock from anemia, loss of condition, emaciation and death in untreated cases. It is one of the major constraints to improved livestock production and productivity in Ethiopia. Entomological and parasitological surveys were conducted in the Omo-Ghibe tsetse belt of south Ethiopia to estimate the prevalence of bovine trypanosomosis and the apparent tsetse density (AD), and identify the potential risk factors. For the parasitological study, blood samples were collected from 1508 cattle sampled from 11 districts and assayed using the buffy coat technique and Giemsa-stained thin smears. For the entomological survey, a total of 216 biconical and NGU traps were deployed in all districts. The overall animal-level prevalence of trypanosomosis was 7.8% (95% CI: 6.5, 9.3). The trypanosome species identified were Trypanosoma congolense (75.4%), T. vivax (20.3%), T. brucei brucei (1.7%) and mixed T. congolense/T. vivax (2.6%). Regarding the entomological survey result, a total of 2243 tsetse flies were captured which identified to be Glossina pallidipes (85.1%) and G. f. fuscipes (14.9%). Besides, other biting flies of the genus Stomoxys (n=146) and Tabanus (n=17) were also trapped. The AD noted in the present study was 3.5 flies/trap/day. Both the prevalence of trypanosomosis and AD of tsetse flies were significantly (p<0.05) influenced by altitude. The prevalence of trypanosomosis was also significantly (p<0.05) associated with poor body condition score, black coat color and lower mean packed cell volume while no significant prevalence difference was noted along with age and sex category. In conclusion, the present study suggested that trypanosomosis is an important disease of cattle in the Omo-Ghibe tsetse belt in dry season. The disease is mainly caused by the most pathogenic T. congolense and transmission is predominantly by tsetse flies, particularly G. pallidipes. The study warrants the need for strengthening the vector and parasite control interventions in the area.

Bovine mastitis: prevalence, risk factors and isolation of Staphylococcus aureus in dairy herds at Hawassa milk shed, South Ethiopia.

BACKGROUND: Mastitis is a disease of major economic importance in dairy industry worldwide. It is of particular concern in developing countries like Ethiopia, where milk and milk products are scarce. The objectives of the study were to estimate the prevalence of mastitis, identify the cow-and herd-level potential risk factors and isolate Staphylococcus aureus, one of etiological agents for contagious mastitis, from cows positive for mastitis. A total of 529 lactating cows selected randomly from 95 herds were screened by California mastitis test (CMT) for sub-clinical mastitis. Also 172 milk samples collected from CMT positive cows were cultured for isolation of S. aureus. RESULTS: Based on CMT result and clinical examination, the prevalence of mastitis at herd-level was 74.7% (95% CI: 64.5, 82.8). The corresponding cow-level prevalence was 62.6% (95% CI: 58.3, 66.7), of which 59.2 and 3.4% were sub-clinical and clinical mastitis cases, respectively. S. aureus was isolated from 51.2% of the milk samples cultured and 73.2% of the herds affected with mastitis. In the multivariable logistic regression model, the herd-level factors significantly associated (p < 0.05) with the presence of mastitis were herd size, bedding material, and milking mastitic cows last, while at cow-level, breed, parity, stage of lactation, udder and leg hygiene, and teat end shape were noted to have a significant effect on mastitis occurrence. CONCLUSION: The very high prevalence of mastitis, more importantly the sub-clinical one, in the herds examined revealed the huge potential economic loss the sector suffers. Perhaps this was attributed to lack of implementation of the routine mastitis prevention and control practices by all of the herd owners. The findings of this study warrants the need for strategic approach including dairy extension that focus on enhancing dairy farmers' awareness and practice of hygienic milking, regular screening for sub-clinical mastitis, dry cow therapy and culling of chronically infected cows.

Mange mite infestation in small ruminants in Ethiopia: Systematic review and meta-analysis.

Mange mites are economically important ectoparasites of sheep and goats responsible for rejection or downgrading of skins in tanneries or leather industries in Ethiopia. The objective of this systematic review was to compute the pooled prevalence estimate and identify factors influencing mange mite prevalence in sheep and goats at national level based on the available research evidence. Articles on mange mite infestation of small ruminants in Ethiopia were searched in PubMed, Web of Science, Google scholar and African journals on-line. The review was based on 18 cross-sectional studies carried out between 2003 and 2015 in four administrative states of Ethiopia. Accordingly, the pooled prevalence estimate in a random effects meta-analysis was estimated to be 4.4% (95% CI 3.0, 6.3) although there were evidence of a substantial amount of between-study variance (I(2)=98.4%). In subgroup and multivariable meta-regression analyses, animal species, agro-ecology and administrative state were found to have significant effect on the prevalence estimate (P<0.05) and explained 32.87% of the explainable proportion of the heterogeneity noted between studies The prevalence was found to be higher in goats in lowland agro-ecology. Region wise the highest estimate was calculated for Amhara (6.4%) followed by Oromia (4.7%), Tigray (3.6%) and Southern Nations, Nationalities and People Region (SNNPR) (3.1%). Significant difference was noted between Amhara and SNNPR. The study further revealed that mites of the genus Sarcoptes, Demodex and Psoroptes are the most prevalent mites infesting small ruminants in Ethiopia. Valid studies were lacking from five regional states. As some of these regions are known for their large small ruminant population, further studies are warranted to produce better picture of the infestation at a national level. Meanwhile, the need for monitoring the ongoing control intervention is suggested.

Survey of ixodid ticks in domestic ruminants in Bedelle district, Southwestern Ethiopia.

A survey aimed at determining the status of ticks in cattle, sheep and goats in Bedelle district (Southwestern Ethiopia) was carried out from November 2007 to April 2008. Out of the total 330 animals examined, 314 (95.2%) were found to be infested (harbouring of at least a single tick). High rates of infestations were recorded across all three host species. Factors like month of collection, age and sex of host species did not show significant association with infestation rates. A total of 5,507 ticks belonging to three genera (i.e. Amblyomma, Boophilus and Rhipicephalus) were collected during the study period of which six species were identified. The species of ticks encountered comprise of Amblyomma cohaerens (44.1%), Amblyomma variegatum (13.8%), Amblyomma lepidum (1.2%), Boophilus decoloratus (24.9%), Rhipicephalus evertsi evertsi (14.3%) and Rhipicephalus lunulatus (1.7%). As about 86.7% (4,772) of the ticks were collected from cattle, it was recognised that this could be an evidence of host preference where cattle are serving as principal host while sheep and goats serve as alternative hosts. The role of ecological factors and little attention paid by livestock owners for treatment of animals against ticks are suggested to result in the abundance of ticks. Acaricide spraying should be strategically applied to control ticks. Better result could be achieved if an emphasis is being put on spraying cattle. Studies on tick-borne diseases, involvement of wildlife species as well as related factors are recommended as they may provide a valuable basis for designing and launching an all-round control programme in the country.

Gastrointestinal nematode infections in small ruminants under the traditional husbandry system during the dry season in southern Ethiopia.

A cross-sectional study was conducted from November 2008 to February 2009 to investigate the prevalence and intensity of infection and risk factors of gastrointestinal (GI) nematodes in small ruminants kept under the traditional husbandry system in two districts in southern Ethiopia. Faecal samples collected from a total of 510 small ruminants (284 sheep and 226 goats) and analysed by a modified McMaster technique revealed that 222 animals (43.5%) were found to be infected with one or more GI nematodes. Five identical genera of nematodes were found in both sheep and goats, which in order of predominance were Haemonchus (56.3%), Trichostrongylus (39.6%), Oesophagostomum (22.9%), Trichuris (21.6%) and Bunostomum (10.4%). No significant (p > 0.05) differences were observed between sheep and goats proportions except for Trichuris (p < 0.05). In both sheep and goats, most of the animals were heavily infected showing faecal egg counts (FECs) above 1,200 epg. Sheep had a significantly (p < 0.05) higher mean FEC than goats. In sheep and goats, both the prevalence of GI nematodes and mean FEC were significantly (p < 0.001) associated with body condition score and faecal consistency but not with district, sex and age (p > 0.05 for each factor). In conclusion, the observation of a strong association of GI nematodes with poor body condition coupled with heavy intensity of infection in the majority of infected animals and an abundance of nematode genera of widespread economic and pathological significance warrants the institution of appropriate control measures that should necessarily include improvement of the nutritional status of the animals.

A cross-sectional study of trypanosomosis and its vectors in donkeys and mules in Northwest Ethiopia.

A preliminary study was conducted in January 2009 in four peasant associations (PAs) selected from two districts in Benishangul Gumuz Regional State, Northwest Ethiopia to investigate the prevalence and species of trypanosomes infecting donkeys and mules and identify the fly vectors playing a role in the transmission of trypanosomosis. Blood samples were collected from a total of 334 donkeys and 52 mules and examined by dark ground/phase contrast buffy coat technique and Giemsa-stained blood smears. Accordingly, trypanosome species were encountered in 6.3% of the examined donkeys (n = 21) while none of the mules examined was positive for trypanosome infection. Trypanosomes and tsetse flies were detected in two of the four PAs surveyed (Tsetsa adurno and Bamadone) with significant (P = 0.004) difference in prevalence. The inability to find trypanosomes in the other two PAs (Ura and Ashura) was most likely due to the absence of appropriate fly vectors. Three species of trypanosomes were detected in donkeys, which in order of predominance were Trypanosoma congolense (52.4%), Trypanosoma brucei (28.6%), and Trypanosoma vivax (19.05%). There was a significant (P = 0.008) difference in mean PCV between trypanosome infected and non-infected donkeys. The body condition score of the donkeys was significantly associated with both prevalence of infection (P = 0.009) and mean packed cell volume (PCV; P < 0.0001). No significant difference was observed between male and female donkeys regarding both prevalence of infection and mean PCV (P > 0.05 for each factor). The entomological surveys revealed the presence of Glossina morsitans submorsitans and other biting flies of the family Stomoxys, Tabanus, and Haematopota. In conclusion, the prevalence of trypanosomosis obtained in the current study is generally low compared to previous studies. As the present study design was a cross-sectional, one that only depicts a momentary picture of the infection status in the herd, a further longitudinal study that makes use of more sensitive techniques and entomological survey is recommended.

Lungworm infection in small ruminants: prevalence and associated risk factors in Dessie and Kombolcha districts, northeastern Ethiopia.

A cross-sectional study was conducted from November 2008 to March 2009 to estimate the prevalence of lungworm infection and to investigate some of the risk factors associated with small ruminant lungworm infections in Dessie and Kombolcha districts, northeastern Ethiopia. Faecal samples were collected from randomly selected 404 animals (240 sheep and 164 goats) to examine first stage larvae (L(1)) using modified Baerman technique. One hundred and thirty eight animals (113 sheep and 25 goats) were also subjected to postmortem examination to detect the presence of adult lungworm parasites. The overall prevalence recorded by faecal and postmortem examinations were 36.9% and 62.3%, respectively. Prevalence of lungworm infection was significantly higher (OR=2.1, 95% CI=1.2, 3.5) in sheep (40.4%) than in goats (31.7%). The proportions of infection by Dictyocaulus filaria (D. filaria), Mullerius capillaris (M. capillaris) and mixed infection were 1.3% (3/240), 28.3% (68/240) and 10.8% (26/240) in sheep; and 20.1% (33/164) by M. capillaris and 11.6% (19/164) with mixed infection in goats. Animals above one year (OR=8.7, 95% CI=4.8, 15.6), non-dewormed animals (OR=10.4, 95% CI=5.6, 19.3) and those sampled during November (OR=3.6, 95% CI=1.5, 8.6) had higher odds of infection prevalence than animals in corresponding groups. The mean count of L(1) larvae of D. filaria and M. capillaris were 5.4 (95% CI=3.6, 7.3) and 39.3 (95% CI=33.7, 44.9) in ovine and 4.5 (95% CI=3.1, 5.8) and 34.1 (95% CI=27.2, 41.1) in caprine, respectively. The recorded average larval count of the two parasitic species varied significantly in both sheep and goats. This study showed high prevalence of lungworm infections which impairs the productivity of small ruminants, implying the need for control intervention.