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Background Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic progressive granulomatous enteritis affecting ruminants and a wide variety of domestic and wild life species worldwide. Although there are reports of clinical cases of paratuberculosis in different veterinary clinics in Ethiopia, there is no epidemiological data on this disease in Ethiopia. Thus, this study was formulated to investigate the prevalence and pathology of paratuberculosis in apparently healthy cattle slaughtered at ELFORA export abattoir. Small intestines and associated mesenteric lymph nodes of 400 cattle slaughtered at ELFORA export abattoir were examined for gross pathological lesions of paratuberculosis. The diagnosis was confirmed by histopathological examination. The microscopic lesions were then graded on the basis of the type and amount of cellular infiltrations. Results When the intestines and the corresponding lymph nodes were examined in the slaughterhouses the prevalence of paratuberculosis gross lesions was 11.25% (45/400). The gross lesions were characterized by intestinal thickening, mucosal corrugations and enlargement of associated mesenteric lymph nodes. Histopathologically 17.9% (8/45) of the cattle with gross lesion were found to have microscopic lesion compatible with paratuberculosis. The microscopic lesions were characterized by granuloma of different grades. The grading of the microscopic lesions revealed 2 animals had grade I, 4 grade II and 2 grade III lesions. Conclusions This study indicated the occurrence of paratuberculosis in cattle of Ethiopia using gross pathological examination of tissue samples. However, gross pathology alone cannot be used as a diagnostic tool and the findings stress the importance of a careful histopathological examination for confirmation of the gross lesions. We conclude that paratuberculosis is prevalent in cattle of Ethiopia for the first time and the result warrants for further nationwide study of the disease to establish its epidemiology and economic significance.

There is paucity of information in the epidemiology and pathology of tuberculosis in swine though the endemic occurrence of bovine tuberculosis was elucidated in Ethiopia. A cross-sectional study was employed to investigate the epidemiology of Mycobacterium tuberculosis complex and Mycobacterium avium complex in swine. The study was conducted from September 2016 to December 2017 using single intradermal comparative tuberculin test, gross pathology and histopathology. Tuberculin test was carried out in farmed swine of central Ethiopia while the necropsy at Addis Ababa Abattoirs Enterprise, Ethiopia. Of the total 329 heads of swine tuberculin tested by bovine purified protein derivative antigen, an animal level prevalence of 3% (95% CI: 2-6) and a herd level prevalence of 11% (95% CI: 1-49) were observed at a cut-off value of >2mm. Multivariable logistic regression analysis revealed the protective exposure effect of body condition to tuberculin test positivity in swine (Adjusted OR: 0.06; 95% CI: 0.0-1.1; P: 0.055). Swine were predominantly in close proximity with dairy cattle which is an important risk factor for the transmission of bovine tuberculosis from cattle to swine. Necropsy study of tuberculosis-like lesions in 640 heads of swine revealed an overall lesion prevalence of 4.1 % (95 CI: 2.8-6.0). In conclusion, the present study demonstrated the occurrence of swine tuberculosis in low prevalence in farmed swine and swine slaughtered atAddis Ababa Abattoirs Enterprise in central Ethiopia. Further in-depth study covering larger sample size and wider areas is warranted so as to identify the prevalent species and their zoonotic importance. Keywords: Abattoir; Epidemiology; Ethiopia; Pathology; Swine; Tuberculosis

Bovine tuberculosis (bTB) challenges intensive dairy production in Ethiopia and implementation of the test and slaughter control strategy is not economically acceptable in the country. Vaccination of cattle with Bacillus Calmette-Guerin (BCG) could be an important adjunct to control, which would require a diagnostic test to differentiate Mycobacterium bovis (M. bovis)-infected and BCG-vaccinated animals (DIVA role). This study describes an evaluation of a DIVA skin test (DST) that is based on a cocktail (DSTc) or fusion (DSTf) of specific (ESAT-6, CFP-10 and Rv3615c) M. bovis proteins in Zebu-Holstein-Friesians crossbred cattle in Ethiopia. The study animals used were 74 calves (35 BCG vaccinated and 39 unvaccinated) aged less than 3 weeks at the start of experiment and 68 naturally infected 'TB reactor' cows. Six weeks after vaccination, the 74 calves were tested with the DSTc and the single intradermal cervical comparative tuberculin (SICCT) test. The TB reactor cows were tested with the DSTc and the SICCT test. Reactions to the DSTc were not observed in BCG-vaccinated and unvaccinated calves, while SICCT test reactions were detected in vaccinated calves. DSTc reactions were detected in 95.6% of the TB reactor cows and single intradermal tuberculin positive reactions were found in 98.2% (95% confidence interval, CI, 92.1-100%). The sensitivity of the DSTc was 95.6% (95% CI, 87.6-99.1%), and significantly (p

Summary Bovine tuberculosis (bTB) is highly prevalent in intensive dairy farms of the urban “milk‐sheds” in Ethiopia, and vaccination could be a cost‐effective disease control strategy. In the present study, the efficacy of Bacillus Calmette–Guerin (BCG) to protect against bTB was assessed in Holstein–Friesian calves in a natural transmission setting. Twenty‐three 2‐week‐old calves were subcutaneously vaccinated with BCG Danish SSI strain 1331, and matched 26 calves were injected with placebo. Six weeks later, calves were introduced into a herd of M. bovis‐infected animals (reactors) and kept in contact with them for 1 year. In vitro and in vivo immunological tests were performed to assess immune responses post‐vaccination and during exposure. Successful vaccine uptake was confirmed by tuberculin skin test and IFN‐γ responses in vaccinated calves. The kinetics of IFN‐γ responses to early secretory antigen target 6 and culture filtrate protein 10 (ESAT6 and CFP10, respectively) and tuberculin skin test responses post‐exposure suggested that the animals were infected early after being placed in contact with the infected herd as immunological signs of infection were measurable between 2 and 4 months post‐initial exposure. Protection was determined by comparing gross and microscopic pathology and bacteriological burden between vaccinated and control calves. BCG vaccination reduced the proportions of tissues with visible pathology in vaccinates compared to control calves by 49% (p

BACKGROUND: The Northwest region of Ethiopia is affected by both tsetse and non-tsetse transmitted trypanosomosis with a huge impact on livestock productivity. The objective of this experimental study was to determine clinical and pathological findings in young Zebu cattle experimentally infected with Trypanosoma vivax isolates from tsetse infested and non-tsetse infested areas of Northwest Ethiopia. A total of 18 cattle (Bos indicus) aged between 6 and 12 months, purchased from a trypanosome-free and confirmed to be trypanosome negative divided into three groups of six animals were used. Animals in the first two groups (Group TT: tsetse infested isolate infected and Group NT: non-tsetse infested isolate infected) received 2 mL of infected blood from donor animals at 10(6) trypanosomes/mL, and the remaining group was non-infected control (NIC). Each group was observed for a period of eight consecutive weeks, daily for clinical signs and once per week for parasitaemia. Postmortem examinations were done on euthanized animals, and tissue samples were taken for histopathological analysis. RESULTS: The prepatent period of the disease was earlier in the NT group 6 days post infection (dpi) than TT group 12 dpi. The infection was characterized by reduced feed intake, intermittent pyrexia and parasitaemia, enlarged lymph nodes, lacrimation, reduced feed intake and emaciation. Less frequently diarrhea, oedema and nervous signs were observed in both groups of infected animals. At necropsy, infected animals showed enlarged spleen, enlarged lymph nodes, pneumonic and emphysematous lung, enlarged liver, and haemorrhages on the brain and intestine. Histopathological analysis revealed lymphoid hyperplasia of the spleen, necrosis of the liver, encephalitis and hyperplasia of lymph nodes. CONCLUSION: Trpanosoma vivax isolates from both tsetse infested and non-tsetse areas showed a variety of virulence factors leading to the development of acute clinical signs, gross and histopathological lesions. However, the parasitaemia and clinical signs appeared earlier in the NT compared to TT infected groups. ispartof: BMC Veterinary Research vol:11 issue:1 ispartof: location:England status: published

2 Abstract: An outbreak of infectious bursal disease affecting 20-45 days old broiler and layer chickens was investigated for the first time in Ethiopia in the months of March and April 2002. Death of chickens started at the 30 day of age and continues to the 55 day. The mortality rate of the disease in different poultry houses th th ranges from 45-50 %. The over all mortality rate was 49.89%. Broiler mortality was 56.09% while 25.08% for layer chickens. The major clinical symptoms were sudden drop in feed and water consumption, sever depression, white watery droppings and mass death. Grossly, hemorrhages in leg muscles, degeneration of the pectoral muscle, white mass (Urate deposit) in kidneys and in Cloaca were frequently observed during post mortem examination. In addition, haemorrhagic & swollen bursas filled with straw colored fluid were identified in few cases. Histopathology revealed hyperplasia of the reticulo-endothelia cells and interfollicular tissue of affected bursa of fabricius. The Agar Gel Immuno Diffusion (AGID) Test detected precipitating antibodies against Infectious Bursal disease virus in sera collected from convalescent chicken. Virus cytopathic effect was observed in chicken fibroblast cells (CFC) inoculated with bursa and spleen tissue suspension of sick chicken. Vaccination failures were encountered to Newcastle disease vaccine (Clone 30). This paper probably is the first to report the occurrence of infectious bursal disease in Ethiopia as the country has been known to be free from Infectious Bursal Disease(IBD).

Ectoparasites are the major causes of skin lesions in animals. Clinical, skin scraping examination, and histopathological studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. Mange mites, lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. Skin biopsies were collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. Of 1,000 sheep and 600 goats examined, 815 (81.50%) sheep and 327 (54.5%) goats were infested with one or more types of ectoparasites. Sarcoptes scabiei var ovis, Demodex ovis, Psoroptes ovis, Bovicola ovis, Melophagus ovinus, and Amblyomma variegatum and other tick species were identified from sheep. S. scabiei var caprae, Demodex caprae, Linognathus stenopsis, and A. variegatum and other tick species were identified from goats. Gross skin lesions or defects observed on the skin include stained and ragged wool, loss of wool/hair, nodules, crusts, lichenification, and fissuring. Microscopic evaluation of H and E stained skin sections revealed lesions in the epidermal layer such as hyperkeratosis, acanthosis, and melanin inconsistency on the basal cells of the epidermis. Follicular keratosis, perifolliculitis, frunculosis, perivasculitis, and aggregates of inflammatory cells (of acute and chronic type) with fibrosis were experiential in the dermal layer of the skin. Most of the skin lesions caused by ectoparasites are overlapping. Thus, ectoparasites control program should be executed to reduce skin lesions as skins are the major export commodity of the country.