Occurrence and fertility rates of hydatid cysts in sheep and goats slaughtered at Modjo Luna Export Slaughter House, Ethiopia

In Ethiopia very limited studies were conducted in small ruminant hydatidosis compared to cattle. A cross-sectional study was conducted at Modjo Luna Export Slaughter House from December 2009 to February 2010 to determine the prevalence and fertility of hydatid cysts. A total of 325 sheep and 440 goats were examined. Examination of lung, liver, kidney, heart and carcass was conducted following standard postmortem procedures. Fertility of hydatid cysts was tested by absence or presence of motility and staining with 0.1% aqueous eosin solution. Out of 325 sheep and 440 goats examined 25 (7.7%) sheep and 27(6.13%) goats had hydatid cysts. The prevalence was high in sheep compared to goats although the difference was not statistically significant (P > 0.05). The organ distribution of hydatid cyst in sheep was 15 (60%) in lung, 9 (36%) in liver and 1 (4%) both the liver and lungs. In goats, hydatid cysts were recovered from 19 (70%) of the lung, 5 (18.5%) of the liver, 1 (3.7%) of the kidney, 2 (7.4%) of the heart and 2 (7.4%) of the muscle. In both sheep and goats the infection was more in lungs, followed by liver. Eighty percent of the cysts found in the lung of sheep were fertile, while there was no fertile cyst detected in the lung of goats and the difference was statistically significant (P < 0.05). In Ethiopia, to break the life cycle of echinococcosis/hydatidosis, public education on habit of feeding condemned organs to dogs should be undertaken

Outbreak of Aeromonas hydrophila associated with the parasitic infection Ichthyophthirius multifiliis in pond of African catfish (Clarias gariepinus) fingerlings at Sebeta, Ethiopia

Outbreak of a disease was observed on African catfish (Clarias gariepinus) fingerlings manifested by white nodules all over the body and hemorrhage in the skin that occurred on June 20, 2011 in an earthen pond at Sebeta, Ethiopia. The outbreak was investigated by using a combination of methods that included clinical observations, gross and histopathology examination and bacterial isolation. On histopathological  examination co-infection of Aeromonas hydrophila with Ichthyophthirius multifiliis a holotrichous ciliate, was found to be the cause of the outbreak. In order to control the outbreak, the fish density was reduced and the fish were removed and treated with sodium chloride (3%) and moved to another properly disinfected pond that contains fresh and good quality water. The former pond was drained and left empty for two  weeks to dry and then lime was added over it before filling it with water. The sick fish got cured after three weeks and no new case was observed; which may be due to development of immunity or the intervention measures taken to control the problem. This intervention protocols need to be further investigated in a properly designed experiment as a possible control of co-infection of these two pathogens in catfish  fingerlings.Keywords: Aeromonas hydrophila, Co-infection, Ethiopia, Ichthyophthirius multifilii

Effect of bovine tuberculosis on selected productivity parameters and trading in dairy cattle kept under intensive husbandry in Central Ethiopia

Bovine tuberculosis (BTB) has substantial impact on fertility, milk, and meat productivity in cattle. However, these assumptions are based on outdated data. Recent global studies on the impact of BTB on cattle productivity are scarce and show sometimes inconclusive and/or contradicting results. This pilot study is the first longitudinal study performed in urban upgraded dairy cattle in Ethiopia that are kept under intensive husbandry. We assessed whether BTB has an impact on various animal productivity parameters and animal movement. Animals (N = 890) included in the study were tested for BTB at least once using the comparative intradermal tuberculin test (CIDT). Fertility, mortality, and offtake were assessed in 21 dairy farms where herd follow-ups over 3 years were performed. In addition, an independent abattoir survey was conducted to assess carcass weight and visible TB-like lesions upon meat inspection. Animal movements (purchasing and offtakes) were documented for each farm. The impact of BTB status on the intervals been birth, service, and calving times and the intercalving intervals was analyzed using a Cox proportional hazards model. The hazard ratio associated with BTB-positive animals was smaller than 1 for all fertility parameters, suggesting that BTB status increases the time between events; however, the effect was small and only statistically significant (95% level) for the time between calving and service. Offtakes included a higher percentage of reactor animals (58%) as compared with non-reactor animals (42%) (p = 0.0001). Overall, reactors were eliminated from the farms within 238.6 days after receiving test results, which was 54.9 days faster than for negative animals. The majority of owners purchased animals within their town or its surrounding. Nearly a quarter of reactors were sold directly to other farms. Animals were also sold further away, including other regions, raising the question of disease spread and the need for an animal tracing mechanism. In the abattoir survey, a total of 349 carcasses were weighed, of which 8% showed visible TB-like lesions and 53.6% had fasciolosis. Negative adult bull carcasses were 7.5 kg heavier than reactor bulls

Epidemiology of Mycobacterium tuberculosis lineages and strain clustering within urban and peri-urban settings in Ethiopia

Background Previous work has shown differential predominance of certain Mycobacterium tuberculosis (M. tb) lineages and sub-lineages among different human populations in diverse geographic regions of Ethiopia. Nevertheless, how strain diversity is evolving under the ongoing rapid socio-economic and environmental changes is poorly understood. The present study investigated factors associated with M. tb lineage predominance and rate of strain clustering within urban and peri-urban settings in Ethiopia. Methods Pulmonary Tuberculosis (PTB) and Cervical tuberculous lymphadenitis (TBLN) patients who visited selected health facilities were recruited in the years of 2016 and 2017. A total of 258 M. tb isolates identified from 163 sputa and 95 fine-needle aspirates (FNA) were characterized by spoligotyping and compared with international M.tb spoligotyping patterns registered at the SITVIT2 databases. The molecular data were linked with clinical and demographic data of the patients for further statistical analysis. Results From a total of 258 M. tb isolates, 84 distinct spoligotype patterns that included 58 known Shared International Type (SIT) patterns and 26 new or orphan patterns were identified. The majority of strains belonged to two major M. tb lineages, L3 (35.7%) and L4 (61.6%). The observed high percentage of isolates with shared patterns (n = 200/258) suggested a substantial rate of overall clustering (77.5%). After adjusting for the effect of geographical variations, clustering rate was significantly lower among individuals co-infected with HIV and other concomitant chronic disease. Compared to L4, the adjusted odds ratio and 95% confidence interval (AOR; 95% CI) indicated that infections with L3 M. tb strains were more likely to be associated with TBLN [3.47 (1.45, 8.29)] and TB-HIV co-infection [2.84 (1.61, 5.55)]. Conclusion Despite the observed difference in strain diversity and geographical distribution of M. tb lineages, compared to earlier studies in Ethiopia, the overall rate of strain clustering suggests higher transmission and warrant more detailed investigations into the molecular epidemiology of TB and related factors

Network analysis of dairy cattle movement and associations with bovine tuberculosis spread and control in emerging dairy belts of Ethiopia

Background: Dairy cattle movement could be a major risk factor for the spread of bovine tuberculosis (BTB) in emerging dairy belts of Ethiopia. Dairy cattle may be moved between farms over long distances, and hence understanding the route and frequency of the movements is essential to establish the pattern of spread of BTB between farms, which could ultimately help to inform policy makers to design cost effective control strategies. The objective of this study was, therefore, to investigate the network structure of dairy cattle movement and its influence on the transmission and prevalence of BTB in three emerging areas among the Ethiopian dairy belts, namely the cities of Hawassa, Gondar and Mekelle. Methods: A questionnaire survey was conducted in 278 farms to collect data on the pattern of dairy cattle movement for the last 5 years (September 2013 to August 2018). Visualization of the network structure and analysis of the relationship between the network patterns and the prevalence of BTB in these regions were made using social network analysis. Results: The cattle movement network structure display both scale free and small world properties implying local clustering with fewer farms being highly connected, at higher risk of infection, with the potential to act as super spreaders of BTB if infected. Farms having a history of cattle movements onto the herds were more likely to be affected by BTB (OR: 2.2) compared to farms not having a link history. Euclidean distance between farms and the batch size of animals moved on were positively correlated with prevalence of BTB. On the other hand, farms having one or more outgoing cattle showed a decrease on the likelihood of BTB infection (OR = 0.57) compared to farms which maintained their cattle. Conclusion: This study showed that the patterns of cattle movement and size of animal moved between farms contributed to the potential for BTB transmission. The few farms with the bulk of transmission potential could be efficiently targeted by control measures aimed at reducing the spread of BTB. The network structure described can also provide the starting point to build and estimate dynamic transmission models for BTB, and other infectious disease

Prevalence of bovine tuberculosis and its associated risk factors in the emerging dairy belts of regional cities in Ethiopia

Bovine tuberculosis (BTB) has become an economically important disease in dairy herds found in and around Addis Ababa City and is emerging in regional cities like Gondar, Hawassa and Mekelle because of the establishment of dairy farms in the milk sheds of these cities. A cross-sectional study to estimate the prevalence of BTB and identify associated risk factors was conducted between February 2016 and March 2017. A total of 174 herds comprising of 2,754 dairy cattle in the cities of Gondar, Hawassa and Mekelle were tested using the Single Intradermal Comparative Cervical Tuberculin (SICCT) test. Data on herd structure, animal origin, body condition, housing condition, farm hygiene, management and biosecurity practices were collected using a pre-tested structured questionnaire. Generalized Linear Models (GLM) and Generalized Linear Mixed Models (GLMM) were used to analyze the herd and animal level risk factors, respectively. The herd prevalence was 22.4% (95% CI: 17–29%) while the animal prevalence was 5.2% (95% CI: 4–6%) at the cut-off >4 mm. The herd prevalence rose to 65.5% (95% CI: 58–72%) and the animal prevalence rose to 9% (95% CI: 8–10%) when the severe interpretation of >2 mm cut-off was applied. The mean within-herd prevalence in positive farms at the cut-off >4 mm was 22.7% (95% CI: 15–31%). At the herd level, the analysis showed that herd size, farm hygiene, feeding condition and biosecurity were significantly associated with BTB status, while new cattle introductions showed only borderline significance and that age of farm, housing condition, farmers’ educational status and animal health care practice were not significant. At the animal level, the results showed that age and animal origin were identified as significant predictors for BTB positivity but sex and body condition score were not related to BTB status. Descriptive analysis revealed that herds having ‘BTB history’ showed slightly higher likelihood of being BTB positive compared to farms having no previous BTB exposure. In conclusion, this study showed relatively lower average prevalence in the emerging dairy regions as compared to the prevalence observed in and around Addis Ababa City, warranting for implementation of control program at this stage to reduce or possibly stop further transmission of BTB

Incidence rate of clinical bovine mastitis in selected smallholder dairy farms in Gondar town, Ethiopia

A study was conducted in Gondar town in six selected smallholder farms from August 2005 to January 2006 for six months to measure incidence rate of clinical bovine mastitis. Monitoring was performed by animal attendants of each farm after training and supervision of the monitoring activities and collection of data was performed by the researchers. Farmers identified cases of clinical mastitis on the basis of abnormalities in milk, in the udder or systemic abnormalities of the cow. A second or third case of clinical mastitis in the same lactation was considered a new case if at least 14 days had passed between the previous and the current case of clinical mastitis. The average incidence rate of clinical bovine mastitis at cow level was found to be 21.26 per 100 cow-years at risk (0.21 per cow-year at risk). Among the six farms, the highest incidence rate observed was 63.49 per 100 cow-years time and no case was recorded in two farms

Land use land cover changes along topographic gradients in Hugumburda national forest priority area, Northern Ethiopia

This study investigated the influence of topographic variability on land use land cover (LULC) change in Hugumburda national forest priority area. The study was based on three periods of LULC maps derived from satellite imageries: Landsat TM for 1985, Landsat ETM+ for 2000 and Landsat OLI for 2015, and topographic attributes derived from ASTER digital elevation model. Supervised image classification was carried out using Maximum Likelihood classifier algorithm. Changes in LULC vis-a-vis topographic variability (altitude, slope and aspect) were assessed based on overlay analysis in a GIS environment. Six LULC classes were identified with an overall accuracy of 93% and Kappa statistics of 0.90. Shrubland and forest land were the dominant LULC types which respectively accounted for about 36% and 26% in 1985 and 39% and 33% in 2000. Forest land (35%) followed by shrubland (30%) continued to be the dominant LULC types in 2015. Between 1985 and 2015, about 23% of the study area showed changes in LULC which constitute increase in forest cover by about 715 ha mainly at the expense of shrubland. Steep slopes, higher altitudes and Northeast aspect were important topographic attributes where marked increased in forest cover was observed. The increase in forest cover along steep slopes, higher altitudes and Northeast aspect can be used to stimulate further expansion of forest cover along similar topographic conditions. This study demonstrated that topographic variability plays an important role in controlling LULC changes. Detailed investigation of drivers of the increased in forest cover is required to scale up the success in other regions with similar climatic and topographic settings

Adoption of biosecurity practices in smallholder dairy farms in Ethiopia

Dairy production is an important livelihood source for smallholder dairy farmers who produce the majority of milk consumed and traded in Ethiopia. Dairy production is, however, constrained by livestock diseases that impact farm productivity, food safety, and animal welfare. Biosecurity measures (BSM) include all risk reduction strategies designed to avoid the introduction of pathogenic infections from outside and minimise the spread of diseases within dairy herds. This study used a cross-sectional survey to investigate the adoption of BSM in dairy farms in Addis Ababa and Oromia regions of Ethiopia. Using a questionnaire, scores for adopted external and internal BSM were calculated based on the Ghent’s University Biocheck tool to compare the performance of different farms in Ethiopia. The weighted external biosecurity score was 49.1%, which was below average (below 50% adoption), while the weighted internal biosecurity score was 55.5%. Low adoption of crucial BSM increases the risk of disease introduction into dairy farms and transmission within herds. Adoption of BSM at the farm level was driven by individual, demographic, and socio-economic drivers, including education, farming system, milk value chain, and farming experience among others. Results of this research reveal low adoption of BSM and the imperative to encourage farmers to implement BSM can lead to a reduction in disease pressures and, thus, a reduction in antibiotic use and increased dairy farms productivity, and improved animal health and welfare. Farmers can be encouraged through proactive engagement with veterinarians and extension professionals. Moreover, creating a favourable policy environment can support farmers to adopt and implement BSM, given the known fact that “prevention is better and cheaper than curing diseases.