Browsing by Author "Tilaye Demissie"
Now showing 1 - 10 of 10
Results Per Page
Sort Options
Item Characterization of Infectious Bursal Disease Lesion and Molecular Detection of the Virus from Outbreak Cases in Poultry Farms in Selected Towns in Central Ethiopia(Addis Ababa University, 2023) Meron Teshome; Tilaye DemissieIn Ethiopia, chicken production is challenged by infectious diseases among which infectious bursal disease frequently occurs as outbreaks and causes significant number of deaths. It causes mortality to chickens aged between 3 to 6 weeks old. This cross sectional study was conducted in Bishoftu, Gelan, Mojo and Dukem poultry farms that had infectious bursal disease outbreak between December 2022 and April 2023. Purposive sampling method was employed in which samples were collected from 100 chickens showing clinical signs and indicative gross pathological lesions during postmortem. Based on questionnaire, 74% of the respondents said they regularly vaccinate their chickens for infectious bursal disease properly whereas 26% didn’t have proper follow up and gave vaccines repeatedly. Based on occurrence of diseases, 52% of respondents said, they had gumboro like disease in their poultry farm previously. And 74% of owners burn or buried dead birds but 26% used to throw the dead chickens out. Vascular disorder mainly hemorrhage and organ swelling were the most frequent gross lesions observed in many organs. The depletion of the lymphoid follicles and formation of cystic structure both in the cortical and medullary regions of bursa with accumulation of necrotic debris in the cystic structures was frequently examined microscopic lesion in bursa. Hyperplasias of the bursal inter-follicular epithelial and formation false glandular structure were also observed. In spleen, lymphocytic depletion in both white pulp and red pulp and hemorrhages in the trabecular sinuses were the common microscopic lesions. Severe hemorrhages in the interstitial space and necrosis of renal tubular epithelium were the repeatedly observed lesion of kidneys. The common microscopic lesions of the proventriculus were hemorrhage into the inter-glandular connective tissue, necrosis and slough off of the proventricular epithelium. Liver showed multifocal hepatocellular necrosis. Based on lesions and molecular detection result, it could be concluded that infectious bursal disease is still the real challenge to poultry producers by causing mortality and reduced growth in young and reduced production in adult chickens. Scheduled vaccination and strict biosecurity should be practiced to reduce the occurrence of the infectious bursal disease in poultry farms.Item Comparative Evaluation of Pathological Lesions in Fish Collected from Different Effluent Sites in Lake Batu and Lake Hawassa, Ethiopia(Addis Abeba University, 2023) Assaye Desta; Tilaye DemissieA cross sectional study was conducted from November 2022 to May 2023 with the objective of comparatively evaluating gross and microscopicl lesions in fish collected from different effluent sites that were identified based on water chemical analysis in lake batu and lake hawassa. Water and fish samples were collected from effluent and reference sites. Mean (±SD) of water quality parameters were statistical different for a mmonia, nitrate, nitrite, silica, total dissolved solute (TDS) and alkalinity by sampling sites (P < 0.05). Mean for ammonia, nitrite, silica and alkalinity were found significantly higher (P<0.05) in Lake Batu water samples compared to Lake Hawassa. Means of all analysed water quality parameters were found significantly higher (P < 0.05) in effluent site of Lake Batu compared to reference sites. Similarly, except nitrite the mean water quality parameters were found significantly higher (P < 0.05) in effulent site compared to reference site for Lake Hawassa. Based on logistic regression analysis (OR) fish collected from lake Batu were 2.46 times more likely to develop gross gill lesions (P<0.05) ; and 1.8 times likely to develop gross skin lesions (P<0.05) than fish collected from lake Hawassa. Regarding sites of fish collection, fishes collected from effulent sites were 2.95 times mor likely to develop gross gill lesions (P<0.05); 4.67 times more likely to develop gross liver lesions (P<0.05) and 2.98 times more likely to develop gross skin lesions (P<0.05) compared to reference site in lakee Batu. For Lake Hawassa; fish collected from effulent site were 2.9 times more likely to develop gross gill lesions and 2.98 times more likely to develop gross skin lesions (P<0.05) in effulent sites compared to reference site. Based on microscopic lesions grading; la mellar necrosis for gill, multifocal hepatocelular necrosis and biliary epithelium necro sis for liver, and epidermal cell necrosis for skin were stage III lesions. Stage III lesions were identified more frequent for lake batu effulent site than lake hawassa effulent site and stage III lesions were nor identified for reference sites of both lakes. Based on microscopic lesions, haemorrhage, aneurysm and lamellar fusion in gill; aneurysm and hydropic degeneration in liver; haemorrhage, aneurism and separation of layers in skin, were stage II lesions. Stage II lesions were frequently identified in fish collected from effulent sites of both lakes and less frequent in reference sites of both lakes. Stage I lesions were lymphocytic infiltration, hyperplastic primary and secondary lamellae and goblet cell hyperplasia in gill; lymphocytic infiltration in liver; lymphocytic infiltration in skin. Stage I lesions were found in both reference and effluent sites of both lakes. It could be summarized that severe necrotic lesions (stage III) and degenerative and hemorrhagic lesion (stage II) swere more ferquent in fish collected from effulenet site than refrence site and this was also in parelell to chemical parameters of water quality. It could be concluded that the majority of stage III & stage II lesions were probably induced by contamination of lake waters by town sewerage, agricultural and industrial wastes. It also looks that lake Batu is more contaminated than lake Hawassa (based on lesion stages & water quality parameters), however, this need further detailed study. We think the result can be basics for further study and we recommend more detailed study.Item Comparative Study on Lesions of Reproductive Disorders of Cows and Female Dromedary Camels Slaughtered at Addis Ababa, Adama and Akaki Abattoirs with Bacterial Isolation(2017-06) Aynalem Mandefro; Tilaye DemissieA cross-sectional study was conducted from November 2016 to May 2017 on reproductive organs of cows and dromedary camels slaughtered at Akaki slaughter house, Addis Ababa and Adama municipal abattoirs to compare lesions and bacteria isolates. A total 280 reproductive organs (140 form cows and 140 from camels) were grossly inspected. Grossly visible lesions were documented and tissue samples with lesion were collected for histopathological lesion characterizations and bacteriological isolations. Various pathological lesion with different degrees of severity were observed in 36.4% (n=51) and 34.2 % (n=48) of cows and dromedary camels, respectively. Age, species and body conditions of animals were not statistically associated with most of the disorders (P>0.05). Comparatively, in cow the most frequently observed lesions were that of ovaries 16.4% while in camels it was that of uterus 21.4%. Grossly, endometritis were characterized by congestion in acute cases and congestions and thickening in chronic cases. Microscopically, endometrial glands degenerations, sloughing of epithelium, periglandular cuffing and infiltrations of inflammatory cell were some of characteristics change observed in endometritis. Grossly, the follicular cyst were large, some of them occupied the entire ovary and very thin walled. Microscopically, the follicular cysts were characterized by extremely thin granulosa layers. Most of endometritic tissues cultured for bacterial isolations were positive for either single and/or mixed bacterial infection. Staphylococcus species 28.5%, Streptococci species 19.6%, Coynebacterium species 8.9%, Escherichia coli 26.7%, Salmonella species 10.7% and Klebsiella species 5.35% were isolated from cows uteri, while in the dromedary camels, Escherichia coli 35.5%, Staphylococcus species 26.6%, Streptococcus species 13.3%, Pseudomonas species 6.6 %, Proteus species 4.4%, Salmonella species 8.8% and Klebsiella species 4.4% were isolated. It could be concluded that reproductive organ lesion were important problem in both species of animals and these disorders might be causes of infertility and appearance of these females in abattoir. The role of each identified lesion on infertility needs further investigations.Item Cytological and Pathological Characterization of Tumors of Domestic Animals in and around Bishoftu, Ethiopia(2018-06) Mesfin Mathewos; Tilaye DemissieTumors are one of the disorders that affect domestic animals. The present study was conducted from October, 2017 to May 2018 with the objectives of determining the types and frequencies of tumors of domestic animals based on cytological and pathological characteristics. A cross-sectional study with purposive sampling of animals with swelling or masses was conducted for evaluation of masses by gross examination, cytology and histopathology. A total of sixty neoplastic swelling were identified. Based on cellular origin, the overall frequencies of tumors were found to be 46.7% epithelial, 36.7% unclassified, 13.3% mesenchymal and 3.3% were round cell tumors. Gross lesions observed include firm consistency, cauliflower like lesions, nodular mass, ulcerated, inflamed and haemorrhagic surfaces, pediculate, necrosis, and lobulated mass with irregular margins. Cytologically, most of the epithelial cell tumor and equine sarcoid revealed clusters of cells with different arrangements, deep nuclear chromatin, anisocytosis and anisokaryosis. Where as, all tumors of mesenchymal origin including fibropapilloma showed pleomorphic spindle cells. Mast cell tumors was characterized by its cytoplasmic granules and transmissible venereal tumors by clear punctuate intracytoplasmic vacuoles, cell shape and prominent central nucleoli. Histopathologically, equine sarcoid and papillomatosis were characterized by dermal keratinocytes proliferation, long rete pegs that extend deep into the dermis. Ocular squamous cell carcinoma was characterized by keratin tonofilaments and keratin pearls while, leiomyoma, cutaneous fibrosarcoma, basal cell carcinoma and hemangiopericytomas were characterized plump smooth muscle-like cells, herring bone pattern, cluster of neoplastic basal cells and perivascular whorls of pericyte nuclei, in the respective order. Mammary tumors were characterized by severe cellular and nuclear pleomorphism, and highly infiltrative. Sertoli cell tumor, fibrothecoma, cutaneous mast cell tumor, transmissible venereal tumor and malignant fibrous histiocytoma were chracterized by sheets of sertoli cells, spindle cells with plump thecoma cells, granulated mast cells, round cells with vesicular nuclei and pleomorphic histiocytic cells, respectively. Based on the result it could be concluded that domestic animals were widely suffering from tumors of different origin. Thus, studies involving large sample size, and wider diagnostic tools should be conducted. Key words: Cytology, Domestic animals, Ethiopia, Histopathology, TumorsItem Estrus Characteristics of Menz Breed ewes and Effect of Ostrus Cycle Phases at Initiation of Ovulation Synchonization on Pregnancy Rate(Addis Abeba University, 2024) Marshet Netsere; Tilaye DemissieThe study was conducted from January to April 2024 with twofold objectives: to characterize estrus signs and the time of occurrence of estrus events in natural and PGF2α-induced estrus; and to assess the effect of estrus phase at the initiation of ovulation synchronization on plasma progesterone, plasma estradiol, and pregnancy rate in Menz breed ewes. To attain the objectives, two experiments were conducted. Briefly, in the 1st experiment, ewes (n = 12) were kept with vasectomized ram to get data from natural estrus, after which ewes were estrus induced by PGF2α to gather induced estrus data. In the 2nd experiment, ewes (n = 12) were estrus induced by PGF2α, and when ewes showed estrus (taken as D0 of the experiment), they were divided into two groups (n = 6 per group), balancing for age, live weight, and parity. In the 1st part of experiment two, ewes were treated with intramuscular (IM) injection of 50µg GnRH agonist on day 16th of estrus (at follicular phase of estrus, designed as follicular group); at day 7 of GnRH injection, ewes were IM injected with 250µg PGF2α; and at 48 hours of PGF2α (day 9), ewes were IM injected with 50µg GnRH. In 2nd part of experiment two, ewes were treated in a similar protocol as in the 1st part of experiment two, but the 1st GnRH injection was started on the 8th day of the estrus (at the luteal phase of the estrus, designed as a luteal group). In both protocols, ewes were kept with a vasectomized ram, and they were bred by Dorper rams standing estrus. The behavioral and physical signs of estrus were similar to those of natural and induced estrus. Estrus events were not affected (P > 0.05) by estrus source, although mean estrus duration was slightly longer in natural estrus (34.1±2.56 hrs) than induced estrus (32.85±3.540 hrs). The mean duration of natural estrus, interval from the onset of estrus to standing estrus, duration of standing estrus, and interval from standing estrus to estrus end were 34.1±2.56hrs, 17.14±3.52hrs, 4.3±0.5357hrs, and 12.07±1.08hrs, respectively. The mean estrus cycle length was 15.46±1.22 days. The luteolysis rate to PGF2α was 100% in the follicular group within 24hrs of PGF2α injection (P4 changed from ≥1ng/ml to <1ng/ml within 24hrs), however, in the luteal group, all ewes underwent spontaneous luteolysis before PGF2α (P4 <1ng/ml on D7). All ewes in the luteal group did not ovulate to D0 GnRH (P4 remains ≥1 ng/ml) while in the follicular group all ewes were spontaneously ovulated before D0 GnRH (P4 <0.5ng/ml at D0 GnRH). In the luteal group, the ovulation rate to D9 GnRH was 83.33% (P4 changed from >0.5 ng/ml to P<0.5 ng/m), while in the follicular group, all ewes were ovulated (100%) to D9 GnRH. The mean ±SE P4 concentrations were 0.448 ± 0.325 ng/ml at D0 and gradually increased to IX 1.348±0.162 ng/ml on D7 in the follicular group; however, the mean ±SE P4 concentrations were 2.464 ± 0.355 ng/ml at D0 and gradually decreased to 0.252±0.103 ng/ml on D7 in the luteal group. Mean plasma E2 concentration was significantly lower (P<0.05) on D7 (15.48±0.87pg/ml in luteal vs. 23.84±2.641pg/ml in follicular) and D8 (16.685±0.95pg/ml luteal vs. 28.104±2.93pg/ml in follicular, P<0.05) luteal group than follicular group. The pregnancy rate was significantly lower (50%) in the follicular group than in the luteal (83.33%) group (P<0.05). Based on this preliminary study, it could be concluded that the estrus phase at the intuition of ovulation synchronization affects the pregnancy rate in Menz ewes. Moreover, when the protocol was started on the 16th day of estrus (follicular group), ewes were already ovulated, which led to a plasma average P4 level below mid-luteal stage (1.348±0.162 ng/ml) 7 days later (at PGF2α), low pre-ovulatory P4, and a low pregnancy rate. When protocol was started on the 8th day of estrus (the luteal group), ewes underwent spontaneous luteolysis 7 days later (at PGF2α), although the protocol resulted in higher ovulation to D9 GnRH, higher pre-ovulatory P4, and a higher pregnancy rate. To get the best starting day for ovulation synchronization, we recommend a detailed study on the length of estrus stages (pro-estrus, estrus, met-estrus, and di-estrus) and the pattern of corresponding hormonal dynamics per stage (P4, E2, FSH, LH pulse/surge) throughout the estrus cycle of Menze ewes. To overcome the spontaneous ovulation and spontaneous luteolysis encountered in this experiment we recommend a study that asses preferable days to start ovulation synchronization that would provide better pregnancy rate in Menz breed ewes.Item Modulation of Ovarian Function to Improve Suitability for Reproductive Biotechnology Application in Local and Crossbred Cattle(Addis Ababa University, 2022) Tilaye Demissie; Alemayehu LemmaOvarian function is influenced by various intrinsic and extrinsic factors. Breed related variations, nutrition; local environmental conditions are among the major sources of differences in response to application of reproductive biotechnologies. It is of paramount importance to understand specific ovarian functions amenable to modifications in order to improve suitability for advanced technologies such as fixed time artificial insemination (FTAI), ultrasound guided ovum pickup (OPU) and in vitro embryo production (IVP). In the first part of this study, estrus sign/s that best correlate with the time of ovulation and pregnancies rate to insemination at FTAI was evaluated in 27 Boran*Holstein crossbred dairy heifers. The second part explored ovarian response to estrus synchronizing hormones by cow realated factors and pregnancy rate to FTAI after ovulation synchronization using GnRH and PGF2α with or without progesterone augmentation (CIDR vaginal insert) in native Borans and Boran*Holstein crossbred dairy cows. The third part assessed the effect of CL, follicle ablation, administration of different doses/frequency of FSH, and different coasting period in Boran cows. Result indicated that, the frequency of occurrence of various estrus signs, length of estrus, and onset of estrus, was not affected (P>0.05) by estrus type. Irrespective of estrus type, standing estrus (r=1, P<0.05), and mounting other heifers (r=0.87, P<0.05) showed a strong positive correlation with ovulation time. Ovulation rate and pregnancy rate on day 32 was significantly higher (P<0.05) in cows that received CIDR augmentation to the double GnRH and PGF2α protocol compared to those that did not. When time of insemination was considered conception rate to insemination 19h post second GnRH administration was significantly higher (P<0.05) for Ovsynch group compared to Cosynch group. Presence of CL did not influence mean number of follicles aspirated, oocyte recovery rate, and quality of oocyte and cleavage rate. Divided dose of 175 IU FSH and 350 IU FSH ignificantly (P<0.05) improved the mean number of medium and large follicles compared to single dose while the 48h coasting period significantly improved (P<0.05) oocyte grade, oocyte maturation rate and cleavage rate. It could be concluded that standing estrus best predict ovulation time. Insemination scheduled at 19h of standing estrus significantly increase conception rate as this sign best correlates with the mean time of ovulation. Further, CIDR priming to the synchronization protocol greatly improve ovulation rate and subsequent pregnancy. Follicular ablation and administration of divided doses of FSH prior to OPU and a coasting period of just 48hr improves follicular population and oocyte recovery rate. Hwever, future studies are recommended to answer why Boran cows’ with morphologically smaller CL than Boran*Holstein cows have larger amount of progesterone than Boran*Holstein. Why some heifers that ovulated to D0 GnRH did not ovulate to D9 GnRH. As some of the CL that were present at day of start were lost at PGF2α the effect of stages of estrus cycle at the start of hormone treatment shoud be assessed both in Boran and Boran*Holstein cattle.Item Options For Estrus Synchronisation in Crossbred Dairy Cattle: Emphasis on Conception Rate to Insemination on Estrus or Synchronized Ovulation, East Shoa, Ethiopia(2019-06) Addise Ambilo; Tilaye DemissieThe study was conducted from November 2018 to June 2019 to evaluate conception rate to different hormonal manipulation of the estrous cycle and insemination on estrus and without estrus at fixed time in crossbred dairy cattle. Before assigning cows to treatments ovaries were scanned by ultrasonography and postpartum cows (>60 days postpartum) were divided into corpus luteum positive (n= 15) and corpus luteum negative (n= 19). All cows with corpus luteum received single PGF2α and detected for estrus and inseminated at standing estrus. Cows without corpus luteum received GnRH at starting day and PGF2α at day seven, detected for estrus within 48 hours and while those in estrus inseminated (Selectsynch) those did not show estrus received second GnRH at day 9 and inseminated at 16-24 hours of the second GnRH (ovulation synchronization). Dairy heifers (≥2 years) were randomly assigned into two groups. One group (n=14) received CIDR and GnRH at starting day and PGF2α at day seven with CIDR removal. The second group heifers (n =13) received GnRH-on day of start (without CIDR) and PGF2α at day seven. All heifers were inseminated either at standing estrus (Selectsynch) or at fixed time (ovulation synchronization). The estrus response was 93.3% in cows treated with single PGF2α, 68.4% for cows receiving GnRH-PGF2α, 50% for heifer receiving CIDR-GnRH-PGF2α and 53.8% for heifers receiving GnRH-PGF2α. The estrus response for all groups was 67.2%. The conception rate was 66.6% to single PGF2α administration and insemination at estrus, 30.7% for GnRH-PGF2α protocol and insemination at estrus, 33.3% for GnRH-PGF2α protocol and timed insemination for cows. Overall conception rate was 71.4% for heifers receiving CIDR-GnRH-PGF2α protocol and 53.8% for GnRH-PGF2α protocol. The difference in conception rate was not statistically significant (P>0.05). In heifers receiving CIDR-GnRH-PGF2α and inseminated at estrus all conceived (100%), while only 42.8% heifers were conceived in CIDR-GnRH-PGF2α and fixed time insemination and difference was not significant (P>0.05). Conception rate was 57.1% in heifers receiving GnRH-PGF2α and inseminated at estrus while it was 50% in GnRH-PGF2α protocol with inseminated at fixed time insemination. BCS and parity showed statistically significant difference (P<0.05) on estrus response and conception in all treatment protocols. It could be concluded that ultrasound scanning for presence of corpus luteum, single PGF2α administration and insemination at standing estrus would give better conception rate in dairy cows than GnRH-PGF2α protocol. In dairy heifers CIDR-GnRH-PGF2α protocol improve conception rate than GnRH-PGF2α without CIDR in general and in particular CIDR-GnRH-PGF2α with insemination at standing estrus gives 100% conception rate.Item Pathological Characterization of Lesions and Bacteriological Isolation of Causative Agents of Swine Tuberculosis at Bishoftu and Addis Ababa Abattoirs, Bishoftu, Ethiopia(2018-06) Jirata Shiferaw; Tilaye DemissieA cross sectional study was conducted at Bishoftu and Addis Ababa Abattoirs from September 2017 to May 2018 to estimate abattoir based prevalence of tuberculosis in swine, to isolate Mycobacterium species involved and to characterize the lesions. Five hundred and fifty six (556) swine were examined. Tubercle like granulomatous lesion were detected in 19.6% (109/556) of different organs of which 12% (69/556) was in lymph nodes, 5.7% (32/556) in the lungs, 1% (6/556) in the liver and 0.36% (2/556) in the spleen. Based on microscopic changes 4.7% (26/556) of lesions were tuberculous granulomatous type with central necrosis, calcified foci, epitheloid cells admixed with lymphocyte and connective tissue boundries, 3.6% (20/556) pyogranulomatous and 2.5% (14/556) non necrotic granulomatous lesion without epitheloid cells and connective tissue capsules. In lymph nodes, severe depletion of lymphocytes, calcification, cellular debris and aggregation of macrophages were observed microscopically. The tuberculous lesions found in lymph node were statistically significant (P < 0.05) than in other organs. The multivariable logistic regression analysis showed that old aged swine were more likely to have characteristic tuberculous lesion (OR = 3.14, 95% CI, 1.62-6.09) than younger ones. From the tissue cultured, 7.5% (3/40) yield growth on primary culture media. The observed colony morphology was smooth whitish or yellowish color, sticky, off-white and breaks apart easily and two (5% (2/40)) of these growth were acid fast positive by Zeihl-Neelsen staining technique. Based on culture result, and typical histopathologic lesions it could be concluded that pork can be source of tuberculosis to human when consumed under cooked and routine abattoir inspections should be conducted. Therefore, further molecular and biochemical research to isolate the species of microbacteria is highly recommended to elucidate the type of lesion and its magnitude in different body organs by considering large number of swine.Item Pathological Characterization, Viral Isolation and Molecular Detection of Newcastle Disease Virus in Small Scale Poultry Farms in Bishoftu Town, Central Ethiopia.(Addis Abeba University, 2023) Hana Dejene; Tilaye DemissiePoultry diseases are among the major constraints of chicken production in Ethiopia. Of which Newcastle disease (ND) is still one of the most important devastating diseases of chicken. Cross sectional study was conducted from November 2022 to May 2023 on clinically sick chickens to characterize lesions due to Newcastle disease, and to isolate the Newcastle disease virus, in 53 small scale farms of Bishoftu town. Questionnaire survey was done to evaluate farm biosecurity in farms that have had clinical diseases. Necropsy was done on a total of 120 chickens. Viral isolation was done on cell culture and detection of the viral genome was done by reverse transcriptase PCR. A total of 53 pooled tracheal and cloacal swab and tissue specimens were sampled from sick chickens showing clinical signs of Newcastle disease and from apparently healthy chicken that have had contact with diseased chicken. Out of 53 collected pools of swab and tissue samples, 24 pools (45.3%) were positive for Newcastle disease virus by real-time PCR. Newcastle disease virus was isolated from suspected cases in all ―kebele‖ or county with the proportions of isolation of 11.32% for Dembi kebele, 3.77% for Filtuu, 5.66% for Qurqura, 1.89% for Kata, 5.66% for Gorba, and 9.43% for Calalaka. Depression, greenish or white diarrhea, torticollis, labored breathing, respiratory rales and drop in egg production with softshelled egg were commonly observed signs. Hemorrhagic lesions in the proventriculus, intestine, cecal tonsils, and hemorrhagic tracheitis were the common grossly seen lesions. The spleens were enlarged, friable and dark red or mottled, while the kidneys were enlarged, congested and swollen. Among the microscopic lesions were necrosis of the proventriculus mucosal epithelium with mononuclear cell infiltration into the lamina properia; Cecal tonsil hemorrhages, and lymphoid depletion; tracheal mucosa epitheliums necrotized with loss of cilia and interstitial pneumonia. Bursa of fabricates showed lymphocyte necrosis, and cystic structure and interfollicular epithelial hyperplasia. Heart showed myocarditis, and myocardial necrosis. Kidneys showed swelling, pale necrotic areas and microscopic lesions include hemorrhages into the interstitium and renal tubular epithelial cell necrosis. Brain grossly showed encephalitis and hemorrhage, microscopically excessive lymphocytes in and around brain capillaries and multifocal hemorrhages. Based on findings, it could be concluded that Newcastle disease is causing death of chickens, reduced egg production and causes economic loss in the study area. PreventionItem Pathological, Bacteriological and Serological Study on Pneumonic Sheep and Goats With Special Emphasis on Mannheimia, Babersteinia, Pasteurella and Mycoplasma Species(Addis Ababa University, 2012-04-30) Tilaye Demissie; Bulto GiroA prospective, non-probability and purposive type study was conducted from October to April on pneumonic sheep and goats to iso late and characterize Mannheimia, Babersteinia, Pasteurella and Mycoplasma species involved in pneumonia of sheep and goats. The concurrent occurrence of Mannheimia, Babersteinia, Pasteurella and Mycoplasma species together were studied and Mannheimia haemolytica isolates were strain serotyped. Comparative isolation of Mannheimia, Babersteinia and Pasteurella species from the same samples of lung was performed. Conventional bacteriological isolation and identification procedures (Quinn et al., 2002; Sisay and Zerihun, 2003 and OlE, 2004) were used for isolation and identification of Mannheimia, Babersteinia and Pasteurella species. Isolation and identification of Mycoplasma species was conducted according to Miles and Nicholas (1998) and OlE (2008).Growth inhibition by monospecific hyperimmune sera and PCR techniques were used for Mycoplasma species identification. The total isolation rate fi'om pneumonic lung from both sheep and goats were 28 % (78/279) for Mannheimia haemolytica, 3.9 % (11 /279) for Babersteinia trehalose and 2.2% (6/279) for Pasteurella /IIultocida. Total isolation rate of Mannheimia, Babersteinia and Pasteurella species together was 40.7% from pneumonic sheep and 24. I % from pneumonic goats. Serotyping 0 f Mannheimia haemolytica isolates was carried out using IHA against 10 reference antisera. Serotype A2 (2 \.5%), AS (20 .5%), and A I (17.7%) were the three dominant serotypes from total isolates of both species. Serotype A2 (26.3%), A1 (17.5%), A8 (15.S/5%) were dominant serotypes from sheep isolates and serotypes A8(33 .3%), A1(19%), and A1(14%) were the dominat serotypes isolated from goat. Serotype AI3 was not isolated both from sheep and from goats and serotypes A8, A7, and A12 were not isolated from goats in the present study. goats in the present study. Four Mycoplasma species namely, Mycoplasma ovipnemoniae (9 isolates), MmmLC (2 isolates), Mmc (I iso late) and Mycoplasma arginini (2 isolates) were identified from sheep. Five Mycoplasma species namely, MmmLC (9 isolates), Mcc (3 isolates), Mccp (3isoaltes), Mmc (4 isolates) and M. arginini (2 isolates) were isolated and identified from goats. The concurrent iso lation rate of Mannheimia haemolytica and Mycoplasma species was 24.6% in sheep and 9.5% in goats. Mycoplasma ovipneumoniae was isolated at IS.S% rate with Mannheimia haemolytica in sheep. This was the highest concurrent occurrence observed while compared to other Mycoplasrna species isolated from Mannheimia haemolytica positive lungs. MmmLC, Mmc and Mycoplasma arginini were also isolated from Mannheimia haemolytica positive sheep. Generally, the isolation rate of Mycoplasma and Mannheimia haemolytica together was significantly lower in goats than in sheep and the only Mycoplasma species isolated together with Mannheimia haemolytica from goats was Mmc. Finally, the results are discussed and compared with previous work. Some points on control strategies and areas of further research are also suggested .