Zoological Sciences

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Serum Immunoglobulin Levels in Healthy Ethiopian School Childhen
(Addis Ababa University, 1982-06) Gebre-Haiiam, Zinabu; Belehu, Ayele
Serum concentrations of immunoglobulins IgG, IgA and IgM in 258 healthy Ethiopian school children and 82 healthy adults rosiding in Addis Abeba were measured by the radial immunodiffusion technique. The results are presented as geometric mean values in mg/100 ml and as percent of the adult mean values. A Btatistical analysis showed that the IgG and IgA concentrations at ages 8 and 7 respectively were lower than the adult values. The inference drawn ftom these results is that the IgG and IgA levels do not reach the adult level until after the age of 8 and 7 respectively. In contrast the IgM level was found to reach the adult level before the age of 7. No truly significant differences were observed in immunoglobulin levels which could be attributed to sex, intestinal parasitic infection or socio-economic status. The merul values for IgG and IgM obtained from this Btudy were found to be higher than the reference values being uBed in the country at the mo-ment. It is thuB suggested that mean immunoglobulin concentration values obtained from this study be used as reference values until further study is made and more refined reference values are set.
Serum Immunoglobulin Levels In Healthy Ethiopian School Children
(Addis Ababa,University, 1982-06) Gebremariam, Zinabu; Belehu, Ayele (PhD)
Serum concentra tions of immunoglobulins I G, IgA and Ig in 258 healthy Et hiopian school children and 82 heal hy adul s residing in Addi s Abeba were measured by the radial immunodiffusion t e chnique . The results a r e presented as geomet r ic mean values in mg/100 ml and a s pe rt ent of the adult mean values . A statist ical a nalysis showed that the IgG and IgA conc ent r ations a age s 8 and 7 r e spectively were lower than the adul t values . The inference drawn from t hese results is that t he IgG and IgA l evels do not reach the adult l e v e l un til a fter the age of 8 and 7 respe ctive l y . I n cont r as t the IgM l e v e l was found t o reach the adult lev e l be fore the age of 7. No truly significant diffe rences were obse rved in immunoglobulin levels which could be a t t ributed to s ex, intestinal pa r a sitic infec tion or soc io-economi c st at us . The mean v alue s for IgG and IgM obta ined from this study were found to be h i gher than the r e fer enc e v a lues being us ed in the country a t t he moment . I t is t hus sugge st ed that mean immunoglobulin conc e n tr ation val ue s obt ained from this study be used a s r e f e r ence v a lue s until furth e r study i s made and more r e fin ed refe r ence va l ues are set .
The Prevallence of Salhonella,Shigellfl and Yersinia Enterocolitica in Adult Diarhoea,L Out-Patients in Sone Hospitals ofAddis Ababa
(Addis Ababa University, 1983-05) Ashenafi, Mogessie; Gedebou, Messele (PhD)
Ninety strains of Shigella and forty-five strains of aslwoel Salmonella Here isola ted from 1000 adult dip,rrho eal ou t-pa tien ts from three hospitals and three clinics in Addis Ababa. No .Yersinia enteroco1i tica "as isolated. Out of the ninety Shigella strains, 57 (63. 3~b) Here Sh. flexneri, 17 ( 1 8 • 970) Sh. dysen teriae, 9 ( 10%) §!! .poydii and 7(7.8%) §!!.sonnei, And among the forty-five Salmonella strains, 17(37.8%) belonged to Group C, 13(28.9?b) Here Group B strains, 9(20%) Here §.typhi,4(8.9) belonged to Group D other than §..,!;yphi and Groups A and E had ono isolate each(2.2%). The standardized agar disk diffusion technique ",as used Hith dislcs of ampicillin, carbenicillin, chloramphenicol, cepha10thiri, gentamicin, kanamycin, polymyxin B, streptomycin, sulphadiazine, tetracycline, and trimethoprim-sulphamethoxazole, All Shigella strains Hore sensitive to oepha10thin(95.6%), gGntamioin(100%), kanamycin(100%) , polymyxin B(100%)and trimethoprim-sulphamethoxazole (1 007~). Sensi ti vi ty to ampicillin (47.7%), carbenicillin(50%), streptomycin(36 • 7%), sulphadiazine (34.4?G) and tetracycline(31.1?b) Has very 10'", Only 15 strains Here sensitive to all 11 drugo. Ninety-threo percent of Sh.flexner=h,70.6% of §!!.dysenteriae, 44.45'0 of §h.boydii and 71.45'0 of §!!.sonnei Here resistant one or more drugs. About 82% of all Shigella strains Here resistant to one or more drugs. J>!ulti;ole drug-resistance Has detected in 82.4% of Sh.flexneri, 70.65'0 of Sh.Qysenteriae, 33.3% of §1a.boydii and 57.1% of §!!.sonnei. About 74')b of Shigella strains "lere multiply resistant, Eighteen different resistance patterns were detected, of which 26,7% ",ere simultaneously resistant to ampicillin, carbenicillin, chloramphenicol, streptomycin, sulpha•diazine, and tetracycline. This pattern ",as the commonest in §h. flexneri (31 %) and Sh.dysenteriae (2910). All Salmonella strains "ere sensitive to gentamicin, polymyxin Band trimethoprim-sulphamethoxazole. All strains of GroupsA,E and §..typhi ",ere sensitive to all drugs. A total of 31 strains (68.9%)",ere sensitive to all drugs. Over 85% of Group B strains ",ere sensitive to all drugs. Group C strains ",ere the least sensitive. Ampicillin, 'C' , . carbenioillin, cephalothin, chlorampheniool, streptomyoin, sulphadiazine and tetracycline ",ere mostly i.net'f"Go't':lV<, against these strains, while only 53% ot' them were sensitive to Ka,amycin, About 1590 of Group B, 64,7% ot' Group C, and 25% of Group D strains were resistant to one or more drugs. The most frequent ",as resistance to eight drugs(17,8%). Of the 45 Salmonella strains, 26,7% were multiply-resistant. In all, seven different resistance patterns ",ere noted. T!le commonest pattern "as seen in 47% of Group C strains:ampioillin/oarbenioillin/ ohlorampheniool/kanamyoin/streptomyoin/sulphadiazine/tetraoycline. The findings in this study ",ere compared ",ith reports from Ethiopia and elsewhere. Based on this study and other reports from Ethiopia, it is reoommended that the aetiology of diarrhoea in all ages be determined, regional reference laboratories be established, the publio be educated on personal hygiene and environmental sanitation, ohemotherapy against diarrhoeal diseases be disoouraged and strj.ot antibiotic policy be iasti tuted in hospitals and nationally.
Study of Malaria Antigens in Blood and Urine Using Solid –Phase Radioimunoassay.
(Addis Ababa,University, 1983-06) Bein, Kifiai
The aim of study was to investigate the presence of malarial Antigens in the body fluids (blood and urine) and consider their Application in the immunodiagnosis of malaria.
A Preliminary Survey of Salmonellae in Cattle Slaughtered at Tile Addis Ababa and Dire Dai'ia Abattoirs
(Addis Ababa University, 1983-06) Ayalew Sahlu; A.Gashe Berhanu (PhD)
In an attempt to assess the incidence of Salmonellae in apparently healthy cattle slaughtered at the Addis Ababa and Dire Dawa abattoirs, a total of 1571 organ samples were collected, out of which 971 were obtained from the former and 600 from the latter. The 971 samples from Addis Ababa abattoirs included 315 spleen, 303 mesenteric lymph node and 353 small intestine samples and these yielded 16 (5.1%), 10 (3.3%) and 8 (2.3:') strains of Salmonellae, respectively. The remaining 600 samples collected from cattle slaughtered at the Dire Dawa abattoir were 200 spleen, 200 mesenteric lymph node and 200 small intestine samples and from these 14 (7/1,),3(1.5%) and 8 (4%) strains of Salmonellae \~ere isolated, respec tively. From this finding the incidence of Salmonellae in the cattle slaughtered at the Addis Ababa and Dire Dawa abattoirs was found to be 5.1% and 7% respectively. No significant difference was observed ( p~ 0.05). Serogrouping of the 59 Salmonella isolates recovered from the 1571 samples showed that, \~i th 24 (40.7%) strains, group D was the most frequent serogroup, to be followed by C1 with 13 (22%) strains, B with 11 (18.6%), C 2 with 6 (10.2')1,) and E with 5 (8.5%). A comparision of the relative frequency of the serogroups in the samples from the two abattoirs also revealed that the most frequent sero['.roup Vias D. The relative incidence of the rest of the serogroups was, however, found to be variable. Of the two culture media used viz., Desoxycholate Citrate Agar and Brilliant Green l>1acConkey Agar, the former was found to be slightly superior in supporting the growth of more strains, both in number ffild type, of Salmonellae encountered in this work
Reservoir Host Studies of Visceral Lelshi•1aniasis in Aba Roba, Souti!-West Ethiopia
(Addis Ababa University, 1989-06) Abebe, Afework; Gemetchu, Teferi (PhD)
From liarch1988 to Arril 1989 investigation of deciles, animal reserve’s of visceral leishManiasis were carried out in the Aha Roha p2asant association, one of the knolln end'~mic foci of visceral h~isl1mar.iasis in Soutlwest Ethiopia (i!'wthern Gmo Administt'dtivp. Rellion). In Vlis study a total of 280 individuals of rliff?rent species of rod,?nts, small and, lar02 carnivores and fel'l domestic animals i'/ere examined. Tissups from the various organs viz., spleen, bone-marrow, liver, skin and a fe\1 tiro'Js of car'iiac blood \'Iere cultured in NNi'l mediur.J overlayed ,lith Locke's solution for the isolation Leishmania. Tissue smears from the aGcve organs wcr" oreparcd from all the animals and checked for the amastigotes of L. donovani. ,qtter.Jpts ,!ere also made to isolate leishmania parasiti!S indirectly, hy the intraocrit.onea.l inoculation of spl,?cn suspension into SUsclJtihle laboratory rodents (hamsters, Salb/c mice and nite mice). To see the possible ~otential reservoir hosts, selectEd species of rodents (born an:! reared in the animal house) were inoculated 'lith L. donovan I promastigotes isolated fro a naticnt in Aba Roba. A Leishmania S0. \'las isolated from the spleen culture of a pround squirrel (Xerus rutilus) and b'/O flaJellates which were considered to be tryranosomes p.re a 1 so reCOVf~r00 from the ) 1 ooel cu ltures of trIo other ground squirrels. The results for the rest of the animals were n
The Effectiveness of Teaching Mathematical Concepts by the Inductive and Deductive Approaches: An Experimental Study in Grade Eleven of Entoto Comprehensive Secondary School
(Addis Ababa University, 1993-06) Yimer, Asmamaw; Desta, Azeb(PhD)
An experimental study was designed to investigate the relative effectiveness of the deductive and inductive approaches in teaching mathematical concepts using specific models. 390 grade eleven students were selected by an achievement test whose content was grade nine and ten mathematics and their average result of semester I of 1992/93 academic year. They were grouped into low-, medium-, and high-achievers on the basis of the above criteria. Each group was divided into two sub groups who did not have significant difference in ability at the beginning. Eight concepts of mathematics were taught for three weeks. A week after the termination of the lessons, a test whose content was the eight concepts taught was administered and 346 students, who attended all the lessons were used for data analysis. The Mann Whitney U-test for larger samples at 0.05 level of significance showed no significant differences between the effectiveness of the two methods and between the two-medium- and the two-high achiever groups. But a significant difference between the two low-achiever groups in favor of the inductive method was found. The overall test results favored the inductive method although there were no statistically significant differences.
VIRAL and Chlamydial Etiology of Acute Respiratory Infection in Infants in Addis Ababa
(Addis Ababa University, 1993-06) Enaro Desalegn; Petros Beyene (PhD)
A case - control study was calTied out to establish the etiologic agents causing acute respiratory infections in infants in Addis Ababa using the immunofluorescence technique. Special attention was given to viruses and Chlamydia trachomatis. The influence of the level of education, passive smoking, breast feeding, and meteorological factors in association with viral infection in acute respiratory infections was investigated using the questionnaire data. Nasopharyngeal aspirates of 225 cases and 178 control infants were studied for the presence of respiratory syncytial virus, parainfluenza virus, influenza virus types A and B, adenovirus and Chlamydia trachomatis between January, 1992 and December, 1992. The overall viral and chlamydial detection rate was 48.9%. The total viral detection rate was 32.9%, out of which respiratory syncytial virus accounted for 31.1 %. Chlamydia trachomatis was detected in 16%. In control infants 2.8% of viral detection was observed. Five control infants had detectable viral antigens but no control infants had detectable Chlamydia trachoma tis antigens. Infants having acute respiratory infection showed significantly higher rates of viral detection than healthy control infants (Chi-Square Yates cOlTected = 52.64, p
Effect of Two Azospirill Um Isolates on the Growth and Nitrogen Content of Tef (Eragrostis Tef (Zucc.) Trotter)
(Addis Ababa University, 1998-06) Zewdie Solomon; Assefa Fassil (PhD); Fetene Masreha (PhD)
Two diazotrophic bacteria, coded as A31 and A32, were isolated from roots of the lefvarieties DZ-01-354 and DZ-01-196, respectively grown in pots on loam soil from Debrezeit. These isolates were characterized to the generic level and further comparison with the description of the type cnltures Azospirillum lipoferum (ATCC 29707) and Azospirillum brasilense (ATCC 29145). These comparisons showed that the two isolates closely resemble A. lipofernm . However, on the basis of some differences in biochemical characteristics, it was suspected that these isolates may be different strains of A. lipoferum. In an attempt to investigate the effect of these isolates on the yield and nitrogen content of tef, inoculation studies on pot grown tef plants was conducted. Root inoculation of seedlings of the two tef varieties with Iml sterile water suspension (107-10' colony forming units (cfu) Iml ) of these isolates produced significant (p < 0.05) increases in height, grain yield, total shoot and root weight, root shoot ratio, total grain nitrogen and protein content of grains. Grain yield increases up to 11. 6 % and total nitrogen and protein content of grains up to 5.7 % over and above un inoculated controls were observed. The bacterial isolate A32 has performed better than A31 in promoting growth and yield of both varieties. Differential plant responses due to different bacterial treatments was found to be significant (p < 0.05) for parameters as height, root shoot ratio and total nitrogen and protein content of grains on both varieties. Of the two tef varieties Dz-01-196 responded better than DZ-O 1-354 to inoculation with either of the isolates as demonstrated in a higher percent increases over the respective controls for most growth parameters The existence of a possible specific interaction between host cultivar and bacterial isolate which governs plant yield responses was suspected. Finally, the potential role of Azospirillum inoculation of tef seedlings on reducing fertilizer requirements was discussed.
Tree Seedlings and Saplings in Treefall Gaps and Under Canopy Shades in Shashemenne-Munessa Natural Forest
(Addis Ababa University, 1999-06) Dalle, Gemedo; Fetene, Masresha(PhD)
Eleven sites including treefall gaps and surrounding shades (under canopy) were studied in the Shashemenne-Munessa natural forest to investigate the dominance, frequency, density and overall importance of established seedlings and saplings of high forest tree species. Examination of the established seedlings and saplings of tree species in the gaps showed that Croton lIlacrostachyus, Rapanea melanophloeos, Maesa lanceolata, Podocmpusjalcatlls and Vernonia auriculijera constitute the most important species in the gaps studied. Croton macrostachyus was found to have the highest percentage value as overall and definitive gapfiller, whereas, Maesa lanceo[ata, Podocmplls jalcatlls and Juniperus procera were found to be the most important gapmakers. These gapmakers constituted 76% of the canopy composition in the Shashemenne-Munessa natural forest. The replacement proportions in gaps were examined to assess their role in the forest community and no evidence was found to support self or reciprocal replacement. The gapmakers-gapfillers comparisons indicated preferential replacement of ahnost all species by Croton lIlacrostachyus, suggesting that the community is undergoing successional change. No significant correlations were found between the gapmakers and gapfillers, canopy composition and gapfillers, gap size and dominance as well as importance values of species. However, statistically significant correlations were found betw.ecn species'cbtniJ,ositioh, a*4 gaRsi,2;~ iul:.~'; :·"'i",'::,,;> May tenus addat, Rapanea lIlelanoph'toeos, DOJlyalis, ,abyssinica,. ,Bersamt1' abyssinica and Teclea lIobilis could be categorized as climax species, whereas, Juniperus procera, Maesa lanceolata, Vernonia auricillijera and Croton macrostachyus could be classified as forest pioneer species. Furthermore, the diversity of tree species was found to be greater in the gaps than under the closed canopy.
Ecological Studies of the African Civet (Civettictis civetta)
(Addis Ababa University, 2000-03) Berhanu Ayalew; Bekele Afework (Professor)
Ecological studies of the African civet (Civetticits civetta) was carried out in Hawassa and Wondo Genet areas of Ethiopia, during July 2012 – March 2014. Civetry distribution and density, population density, diet analysis, seed dispersal and scent marking of civets were investigated. Civetries were distributed along pathways at various locations like forest, plantation, bushy area, grassland, farmland, open area, bare land, lake shore and home garden. Higher density of civetries were recorded in the farmland than in other areas (t = 5.6, df = 3, p < 0.05). A population density of 2.3−12.8 civets/km2 was estimated. Civets feed fruits (36.9%), leaves and shoots (18.3%), roots and tubers (3.4%), invertebrates (19.1%), mammals (13.3%), birds (6.6%) and fish (2.8%) in the present study area. Fruits were the most preferred food item in all habitats. African civet is an effective seed dispersal agent. Over 70% of scent marked signposts were distributed around civetries in the farmland and natural forest areas, while about 35% of the scent marked sign-pots were distributed around civetries in the urban area. Most of the scent marked sign-posts were located at or close distance (< 2 m) to wildlife tracks. The amount of scent marks on sign-posts ranged between 0.0001−1.5110 g. The effect of season and habitat on population density and diet composition was insignificant in the present study area due to the habitat variability and modification. Fruit eating behavior of civets and widespread civetries distribution along various habitats have an important role in seed dispersal and implication for conservation of civets. Key words: African civet, musk, civetry, civiculture, feeding ecology, scent marking, seed dispersal
Studies on the Anopheline Mosquitoes of Metehara and \ Surrounding Areas in Relation to Malaria Transmission
(Addis Ababa University, 2001-05) Balkew, Meshesha; Gebre, Teshome(PhD)
The ecology and behaviour of Anopheles mosquitoes was studied in four selected sites in the Metehara area, Upper Awash Valley, Eastern Ethiopia. The sites represented two insecticide unsprayed villages (Metehara and Gelcha) and two sprayed villages (the Sugar Estate and Buse). Information on the prevalence of malaria cases was also gathered from the Metehara Sugar Estate Hospital and the East Shoa Malaria Control Sector (Nazareth). The results showed that a total of 24,799 microscopically diagnosed malaria cases out of 68,000 blood samples were registered between July 1999 and September 2000 in the two health service rendering organizations. Plasmodium falciparum and P. vivax were found to be responsible for the disease and occur nearly in equal proportions (52.7% P. falciparum and 47.3% P. vivax ). Larval collections from the different breeding habitats revealed the presence of four species of which Anopheles arabiensis was the predominant followed by. An. pharoensis. Similarly, a total of 3639 adult anophelines representing at least eight species were caught using different methods from July 1999 to September 2000. An. arabiensis was the predominant species, forming 95% of all collections followed by An. pharoensis (3.8%). The density of An. arabiensis resting indoors in the sprayed sites was much lower than the density in the unsprayed sites. Consequently, 18%, 21.3%, 66.1% and 69.4% of An. arabiensis exhibited exophily in Gelcha, Metehara, Buse and the Sugar Estate, respectively. The indoor to outdoor biting ratio of An. arabiensis varied between villages: 0.53 in the Sugar Estate, 1.97 in Buse, 0.75 in Gelcha and 2.12 in Metehara town, showing that the species was more endophagic in Buse and Metehara and more exophagic in Gelcha and the Sugar Estate, * : XI The highest man biting rate of 39.5, was recorded in Metehara town and the lowest 8.4 in Buse. An. pharoensis was mostly an outdoor feeder. Of 864 An. arabiensis and 63 An. pharoensis dissected from human bait collections, the average parous rate was 45.1% and 30.2%, respectively, showing An. arabiensis to be longerlived than An. pharoensis. The sporozoite rate of An. arabiensis was 0.77% in parous and 0.21% in nulliparous population, the overall being 0.46%. Similarly, An. pharoensis had sporozoite rate of 5.3% in parous and 2.3% in nulliparous population, the overall being 3.2%. The biting rhythm of An. arabienisis exhibited two to three peaks of activity before and after midnight . The highest biting density occurred after midnight indoors while variation was observed outdoors. The average daily entomological inoculation rate (EIR) of An. arabiensis was 0.05 while that of An. pharoensis was 0.01. The Human blood index (HBI) of An. arabiensis revealed variation between sites/villages being 1 in Metehara, 0.47 in Gelcha, 0.85 in Buse and 0.93 in the Sugar Estate, the overall being 0.65. The HBI varied also between dwelling conditions of mosquito sampling, being highest in human dwellings (0.78) and lowest in animal shelters (0.13) showing the opportunistic feeding behaviour of An. arabienisis. Clearly, An. arabiensis is the most important vector and An. pharoensis a secondaiy vector of malaria in the Metehara area. Insecticide susceptibility studies in Metehara showed that 30% arid 25% of An. \ arabiensis was resistant to DDT and pennethrin , respectively. The level of DDT and permethrin resistance in An. arabiensis does not seem to be epidemiologically dangerous, but requires frequent monitoring. An. arabiensis was found to be highly susceptible to propoxur (carbamate insecticide) .
The Elucidation of Malaria Transmission and its Prevalence in Highland Urban Area, Akaki Town, Addis Ababa, Ethiopia
(Addis Ababa University, 2001-05) Woyessa Adugna; Gebre-Michael Teshome (PhD); Ali Ahmed (PhD)
To elucidate malaria transmission and determine its prevalence in a highland-fringe urban area, Akaki, parasitological and entomological investigations were conducted between October 1999 and October 2000. Review of malaria cases was using records of the Addis Ababa and Akaki health institutions for the years between 1993 and 2000. Parasitological survey was conducted, during a peak malaria transmission season, October through December 1999. A total of 712 persons (264 males and 448 females) were examined for three consecutive months (Oct.-Dec. 1999). Using different mosquito sampling methods a monthly collection of larvae and adult mosquitoes was conducted for 1 year from October 1999 to October 2000. The review of 6 Zonal Health Department records in Addis Ababa indicated that malaria is one of the major causes of outpatient consultation. A significant increase in malaria prevalence was noted after 1996 reaching a peak in 1998. The records do not show the geographical origin of the cases but most of them are believed to be internally imported. This however, can not rule out the possibility of its importation from the peripheral Towns like Akaki, with active malaria transmission considered. The occurrence of malaria outbreak during 1997/98 with its peak in October through November in Akaki and their sharing Plasmodiulll vivax as the dominant species both in Addis Ababa and Akaki suggest the likely hood. A total of2136 blood films were examined, 78 (3.7 %) persons were malaria positive of which 54 (69%) were due to Plaslllodium vivax and only 24 (31 %) due to P. jalcipa/'lIll1. Parasitological surveys done in this study in Akaki Town shows 30 (4.2%) were malaria positive with predominance of P. jalcipal'lIl1l (70%); in the second survey, 48(6.7%) wcre positive with a predominance of P. vivax (93.7%); no case was detected in the last survey. Although prevalence increased with age, the detection of cases in children below the age of 5 years suggested autochthonous malaria transmission in Akaki area. Two Anopheles species were encountered in the larval collection. Anopheles christyi (9\,7%), An. galllbiae s. 1., (presumably An. arabiensis, 6.7%) and An. cinereus (\.6%). In the adult collection, four species of were recorded: An. arabiensis, An. christyi, An. pharoensis and An. coustani. Anopheles arabiensis and An. christyi were the dominant manbiting species in the area. They were both more exophagic and active in the early evening unlike An. pharoensis that showed an endophagic tendency. The dissection of 49 An. christyi, 43 An. arabiensis, 2 An. pharoensis and a single specimen of An. COl/stani turned negative for sporozoites. Anopheles arabiensis might be the major vector in the area. However, further and detailed investigations are required to asceltain the relative importance of An. arabiensis and the other man-biting species (pmticularly An. christyi) in the transmission of malaria in Akaki and surrounding areas to design appropriate control strategy. The findings are discussed
Some Aspects of Carnivore Ecology And Epldemiology in the Bale Mountains, Ethiopia
(Addis Ababa University, 2001-06) Admasu Ermias; Bekele Afework (Professor)
The generalist pathogens of carnivores particularly rabies and canme distemper caused significant mortality to an endangered carnivore, Ethiopian wolf (Callis simellsis), in the Bale Mountains, Ethiopia. For a full understanding of the epidemiology of these pathogens, the ecology and behaviour of both the hosts and the pathogens must be known. However, appropliate data to quantify the likelihood of transmission between hosts in most ecological studies are lacking. Furthermore, when considering carnivore pathogens, the ecology and behaviour of many smaller call1ivores such as civets and mongooses are relatively unknown. Thus, there is a clear need for an intensive study of the behaviour and ecology of a guild of wild call1ivores in the Bale Mountains. Carnivore ecology and epidemiology were studied in the Bale Mountains, Ethiopia. Eight golden jackals (Callis aI/reus), five white-tailed mongooses (Ic1melllllia albicauda), one marsh mongoose (Alilax plaudillosus), one African civet (Civitictis civetta) and one common genet (Gelletta gelletta) were radio-tracked from November 1998 to March 2001. A total of 950 animal locations were obtained. The average home range size for female jackals was 36 kru2 and for males 35 kru2 , range from 7.87 to 64.76 kru2 • The home range size for adult males' white-tailed mongooses averaged 3 kru2 , range from 1.11 to 4.27 kru2 , and the adult female used an area of 2.63 knl. The only tracked marsh mongoose, African civet and common genet nsed an area of 3.93, 11.06 and 1.71 km2 respectively. Home ranges overlapped greatly both within and between species although ten'itoriality among male whitetailed mongooses was demonstrated. Golden jackals and white-tailed mongooses were observed most of the time alone. Male -female pairs were the most tiequently observed social groups in both species. Inter-specific interaction among wild call1ivores, and between wild call1ivores and domestic dogs were observed. The frequency of contacts was higher among domestic dogs, golden jackals, white-tailed mongooses and spotted hyaenas. The pattern of habitat use during delll1ing activity and foraging activity by the radiotracked species was different. Golden jackals used densely covered forests and bushes as denning sites where as they used all habitats during foraging. White-tailed mongooses used underground dens and empty houses for resting but the species intensified its foraging activity in grasslands. The marsh mongoose exclusively used underground dens along the riverbank as denning sites whereas it used riverside habitats as foraging areas. The civet exclusively rested in dense bushes where as the genet largely found resting in trees. Scavenging by the civet and the genet was frequently observed. The microhabitats were particularly important both as denning sites and foraging areas for most species, except for the genet and civet, which exhibited a similar pattern of use of microhabitats and area habitats. The mean density of golden jackals in the highlands and lowlands around the Bale Mountains National Park were the same (1.4 indiv. Ikm2 ). The mean density of domestic dogs was 6.39 and 2.15 individuals/km2 in the highlands and lowlands respectively. The population abundance of golden jackals, spotted hyaena and white-tailed mongoose was relatively high. Analysis of Sera sampled from wild carnivores around the Bale Mountains National Park from 1998-1999 suggests that the carnivore species had been exposed to canine viruses. Large proportion of the sampled golden jackals and Ethiopian wolves were seropositive to canine distemper, canine adenovirus and canine parvovirus. The study established that there is a potential for disease transmission between wild carnivores, and from domestic dogs to wild carnivores.
Population Status, Structure and Diurnal Activity Pattern of the Mountain ny Ala (Tragelaphus Buxlolll) in the Bale Mountains National Park, Ethiopia
(Addis Ababa University, 2001-06) Refera Befekadu; Bekele Afework (Professor)
The study on the population status, structure, and diurnal activity pattern of Mountain Nyala (Tragelaplws buxtoni) was carried out in the Bale Mountains National Park, Ethiopia for foul' months that included wet and dly seasons. Ground total counts were carried out in all area of 13.1 'm/. The study showed that the endangered Mountain Nyala in the Bale Mountains National Park consisted of about 704 individuals. The Male to female ratio is unequal. Females comprise 62.9% whereas male 27.4% and the calves possessed the 9.7% of the sex ratio. Mountain Nyalas' are mainly browsers. The group structure of the animal varied with season, forming large herds during the wet season and dispersing in to smaller groups during the (b)' season. Territorial behaviour was not observed. The population trend of the animal ji-om 1975-1990 indicated a recovel), and increase. But between 1990-1995 a population showed a continuous and steep decline. However, between 1995-2000 the population trend showed a tendency toward recovely. The diurnal activity pattern of the animal showed two feeding peaks early morning and late afternoon. The peak resting tillle was in the middle of the day. Group size changed seasonally. 7 to 12 members in a group are common during dlY and wet season, and the maximum group size observed was 62 during wet season. The vegetation type utilization and distribution of the animal indicated a marked preference for woodland habitat. Howevel~ there was a seasonal change in preference of habitat. The study established that the main threats of Mountain Nyala are habitat destruction, disturbance, livestock abundance, hunting and predation.
Population Status and Some Ecological Aspects of Soemmerring's Gazelle (Gazella Soemmeri11g1) in Aw Ash National Park and Alledeghi Wildlife Reserve, Ethiopia
(Addis Ababa University, 2001-06) GebreMedhin, Berihun
The distribution of Soemmerring's gazelle (Gazella soemmerillgi), which had a wide range in the East Ali"ica, is currently dwindling with the increasing human population density in the previous range. In Ethiopia, it had a wide range in the Eastern and Northeastem part 0 f the country. However, the population is declining, because of the loss of important habitats as a result of overgrazing, indiscriminate killing and other human factors. Field study on the population status and some ecological aspects of the species was conducted every month from January to December 2000 for eleven months in I1ala Sala (Awash National Park) and for nine months (April to December) at Alledeghi Wildlife Reserve. The result indicated that mean populations of 457.8 individuals were found in the selected study site in Alledeghi Wildlife Reserve, and 41.9 individuals were counted at IIala Sala - Awash National Park. Grouping pattem showed that cohesion was stronger. TelTitorial males detain females and other members of the group. The difference in mean group sizes of the gazelle between the two areas was significant. In comparing the two populations based on the main categories the difference was not significant (p=0.795). Mean group size for ANP was 4.4 while for A WR it was 16.8 individuals. A paired-sample t-test comparison of the total fi'equency of categories of the group sizes for the two areas showed a significant difference (p=0.026). Local variation in group size did exist in AWR (p=0.021). But this variable showed no significant difference (p= 0.414) in ANP. Herds of 6 - 10 were most common at Ilala Sala and 20 - 50 at AWR. However, herd size ranges Ii-om 3 - 250 individuals at A WR. Compating seasonal variations in group sizes showed no significant difference. The proPOliioni of time budgets apportioned to the five types of activities vatied among seasons and month~' Feeding activity comprises much of the time budgets of Soemmerring's gazelle ranging fr, m 39.8 to 50.7% during the dry season from 38.4 to 45.7% in the wet season in male an from 51.0 to 59.6% in dry season and from 59.8 to 64.6% in wet season in female. Df:.S:tribution of group sizes in grassland habitats of the two study sites showed a very high si ificant difference (p=O.OO). High proportion of groups of Soemmerring's gazelle was obsen ed in short-sized grass cover in Alledeghi Wildlife Reserve, where as in Awash National Ii frk most were observed in medium-sized grass cover. Open grassland habitat was the best p; rferred habitat to other. V111 ungulate evolves behavioral and morphological adaptations that optimize the tradeoffs between these problems. Thus, within the constraints of effective strategies against predator and successful mating, one would expect strong selective pressures towards efficient use of energy and nutrients for maintenance and reproduction. Ungulates show variation in ecological behavior in response to environmental stress through time and space. Some move to higher elevations in spring and summer in search of nutritious, new growing forage (Festa-Bianchet, 1988), while others migrate to exploit temporal differences in vegetation phenology (Berger, 1991). Forage quality, quantity and predator avoidance influence the migratory behavior of certain mammals (Festa-Bianchet, 1988). Habitat selection by an animal reflects a strategy that enhances survivorship and successful reproduction (Bowyer et ai., 1998). One solution offered to explain how animals deal with conflicting needs to forage efficiently and avoid predation is selection of habitats that minimize the ratio of predation risk to available forage (Pulliam and Danielson, 1991). Conversely, such animals would tend to avoid other habitats in which predation risk is higher and value of food lower. In areas where there is an inverse linear relation between risk of predation and forage, animals would be distributed mostly in the habitat with low predation and high forage. If, however, animals are displaced from this optimal habitat, because of inter-specific competition or dominance interactions with superior individuals, sub-optimal habitats could be selected until predation become too severe or forage too limiting for them to persist (FestaBianchet, 1988). Many of the life history characteristics of ungulates are shaped by risk of predation (Berger, 1991; Festa-Bianchet, 1988; Hilih, 1977), and predators are capable of regulating populations of ungulates under celiain conditions (Van Ballenberghe, 1987; Van Ordsol, 1984). Selection of habitat is likely to depend upon a dynamic set of conditions that include the 'state' of the individual, its environment, and perhaps its past and potential future state (Mangle and Clark, 1986 cited in Festa-Bianchet, 1988). Behavioral information is essential to the full understanding of the ecology of a species. Different animals show different behavioral responses to the ecological changes that occur in their habitats, seasonal changes of the year, and presence or absence of predators, etc. Vigilant behavior, as one of the behaviors observed in response to various changes in the environment, may help an animal to locate food source and avoid capture by predator (Bertram, 1980). Underwood (1982) investigated vigilance behavior in several African antelopes in relation to finding food as well as in avoiding predation. Large predators prefer tall grass for successful hunting. Van Ordsol (1984) noted that hunts by lions were more successful in tall grass than in short grass. On the other hand, prey species like reedbucks of the family Rudincinae prefer long grass to avoid predators (Irby, 1982; Roberts and Dunbar, 1991). Jamlan (1974) suggested that non-cryptic animals have tlll'ee major strategies available to avoid predation: (i) detecting the predator before it initiates the attack, (ii) outLUnning the predator during the attack, or (iii) attacking the predator. This study will examine, in part, the response of the Soel11l11ert'ing's gazelle to predation in different heights of grass cover. Seasonal movements in water-dependent large communities show a wet season dispersal and dry season concentration which can be related to the seasonality of rainfall and water availability, but those similar pattems do not prevail in the water-independent species (Durant et al., 1986). It is suggested that seasonal migration of herbivores in the grassland ecosystems of Eastern Afi'ica is correlated to the availability of green vegetation and hence in the proportion of important nutrients. Different species of animals make seasonal movements between habitats. In areas where food resources change with seasons, populations of mammals are known to move fi'om one type of habitat to another depending upon the season (Began et al., 1986). The availability of food resources affect the population dynamics and distribution of an animal species (Caughly and Sinclair, 1994). Knowledge of the relationship of an animal with its habitat is essential in understanding the ecological requirement of the species (Caughly, 1977). In addition knowledge in the feeding habits of an animal are essential for making and designing strategies for management. Many studies have dealt with the various ecological and behavioral aspects of the Wildlife in Afi·ica. Of the nearly dozens of gazelle species found in Africa, only few are well studied: Thomson's and Grant's gazelles are the most studied fi'om East Africa (Estes, 1967; Walther, 1977), while the dorcas (Gazella dorcas) and dama (Gazella dama) (Salah, 1987; Yoram Yom-tov, 1987; Grettenberg, 1986) gazelles fi'Om North Afi'ica and the Middle East have been studied to some extent. Excessive hunting by people, excessive grazing by domestic livestock, agricultural el(pansion, and other habitat modifications are identified as the main factors that adversely affected most population of the gazelle in the Middle East and Nm1h Africa (Salah, 1987). Little is known about the ecology and population status of SoenmlelTing's gazelle. Soemmerring's Gazelle (Gazella soemlllerillgi) belongs to the family EOl'idae, subfamily Antelopini. This Gazelle is large in size, with an elongated head and a relatively short neck (Dorest and Dandelot, 1970). It is adapted to bush and acacia scrub in hilly areas as well as open grassy plain (Kingdon, 1997). This gazelle generally inhabits thorn bush, open and grassy plain in hilly country and is considered to be both browser and grazer (Estes, 1991). It feeds on grass and herb, but may also browse on leaves of shrubs. Like other African wildlife species, Soemmerring's Gazelle is affected by the rapid growth of human population, which has an increasing demand of new land for agricultural expansion and grazing livestock (Hillman, 1988). In most of its habitats, Soennnerring's gazelle has suffered from decades of uncontrolled hunting with firearms and severe habitat degradation caused by man and domestic livestock, accentuated by recurrent droughts. These factors have reduced this formerly abundant gazelle to scattered, remnant populations and its 10ng-teJID survival is tlu·eatened. It occurs in few conservation areas such as Awash and Yangudi Rasa national parks, which have been considered as the important areas for the conservation of this gazelle. The status of Soemmell'ing's Gazelle is classified as "Vulnerable" in the IUCN's (International Union for the Conservation of Nature and Natural Resources) Red Data Book (IUCN 1990). The species is under high pressure of threat to extinction within its highly restricted distribution. The distribution of Soemmerring's Gazelle in Ethiopia was described as locally common in the N0l1heastell1, Eastell1 and Southeastell1 lowlands (Hillman, 1988). However, recent reports indicate that the species is exterminated over the greater part of their range, and occurs in numerous pockets (Kingdon, 1997). Schloeder et al. (1997) have repot1ed that large propot1ion of the population of the species in the Rift Valley of Ethiopia occurs in the Alledeghi Wildlife Reserve and the adjacent Afdem-Gewane Controlled Hunting Area. Thouless (1995) recorded 2,650 gazelles at the Alledeghi plains on the grassland plain to the West of the A wash River and North of the central part of the Awash West Controlled Hunting area. Soemmerring's Gazelle has also wide geographical range in Eastem Ethiopia. Their status was assessed in Aysha-Jijiga region by Thouless (1995) and in the Ogaden Region by Wilhemi (1997). These repot1s indicated that the population of the species is greatly on the decline. Although the status of Soemmerring's Gazelle is considered stable in the Awash Valley (Schloeder et al., 1997), its size in the Awash National Park (ANP), which is legally protected, has declined as compared to other antelopes (Almaz Tadesse, Personal Communication). The population has declined by over 82% in 27 years and its important habitat shrunk by a similar margin (Schloeder et al., 1997). Assessment of the current status and ecology of So emmer ring's gazelle is impot1ant for the park management and will also provide some information on the existing knowledge gap on ecology of this gazelle.
Intestinal Parasitic Infections among Patients Visiting Gorebellllaa Health Center,, North--Central Ethiopia
(Addis Ababa University, 2001-09) Deneke Asnakech; Mamo Hassen (PhD)
Intestinal parasitic infections (IPIs) which are neglected globally remain among substantial public health concerns in Ethiopia. Up-to-date epidemiological information on these infections is indispensable to effectively control them in a locality. This study was thus aimed at evaluating the extent of IPIs and status of related sanitary practices among patients visiting Gorebella health center, north-central Ethiopia. Patients visiting Gorebella health center in January-April 2016 who were suspected of IPIs were recruited in a cross-sectional survey. Socio-demographic data were gathered using a semi-structured questionnaire. Stool samples were processed by the direct saline smear method. Data entry and analysis was done using SPSS software (version 20). Out of 403 samples examined, 282(70.0%) had one or more intestinal parasites belonging to six different species or types. E. histolytica/dispar/moshkovskii was detected in 205(72.2%) patients followed by G. intestinalis (35(12.4%), A. lumbericoides (33(11.7%), hookworm (12(3.0%), Taenia spp (7(1.7%) and H. nana (4(1.0%). More than half (268(66.5%) of the cases had single infection and only 14(3.5%) were mixed. The result demonstrated the high magnitude of symptomatic IPI in the study area. Simple health promotion actions including education must be scaled-up to sustainably reduce the burden of IPI in the community. The very high prevalence calls for initiation of a deworming scheme in the locality. Keywords: Intestinal parasites, Prevalence, Ethiopia
Population Status And Human Impact on Burchell's Zebra (Eqlllls Blll'chelli, Gray 1824) in Nechisar Plains, Nechisar National Park, Ethiopia
(Addis Ababa University, 2003-01) Doku, Yisehak; Dagne, Kifle(PhD)
The population census of Burchell's zebra (Equus burchelh) and the human impact were carried ollt in Nechisar plains, Nechisar National Park, 515 km south of Addis Ababa from November 2001 to April 2002. Line transect count was used for population census. Social and physical surveys carried out on the range of Burchell's zebra population to find out human impact. The present population density estimate of Burchell's zebra in the Nechisar plains was found to be 16.6 :f: 1.5/1m? The population abundance of Burchell's zebra in the study area was found to be 4482 individuals. This estimate sholVS an increase in population trend compared to the previous one. During the wet season, 57.3% preferred the Nechisar open grassy plain. During the d'yseason, 53.5% preferred Hare hill plateau bushland. Grass and water availability was identified as the main factor influencing the movements and distribution of the Burchell's zebra population in Nechisar plains, especially during the dly season. Observation of feeding processes showed that they feed upon most com ilIOn grasses available but appeared to have prefenmce for particular six grass species. Their local distribution range was contracted during the wet season, 95.9% were observed inside the park. During the dl)1 season, 76.2% were observed inside the park while 23.8% were observed outside the park boundmy. Non-territorial nomadic Burchell's zebra live in social group. The average herd size of one-male harem and bachelor stallion herds was 10.8 and 6.4 individuals. The sex structure of Burchell's zebra population in the Nechisar plains was 34.8% adult male, 41.5% adult female and the rest 23.7% were unsexed immature young. The sex ratio of adult male to adult female was 1.0:1.19. The age stl1lcture of Burchell's zebra population in the Nechisar plains was 76.3% adult, 14.7% subadult, 5.2% juvenile and 3.8% foal. Predators of Burchell's zebra in the Nechisar plains are 28.6% lion (Panthera leo) and 6.5% spotted hyena (Crocuta crocuta), but the other causes of death, 14.5% old age and 49.4% unknown. Burchell's zebras are diurnal herbivores. During the dly season, two resting periods observed. The most important aspects of social behaviour communication were 38.8% visual, 24.2% o!factol)l, 18.8% tactile and 18.2% vocal (or auditory). Agonistic behaviour is observed during sexual display, danger and disputes. These were 53% submissive traits, 25% fighting, and 22% aggressive traits. Larger plain wild and domestic ungulates mix with Burchell's zebra in the Nechisar plains. These are 17.5% Gran! 's gazelle (G. granti), 4.8% Swayne's hartebeest (A. II. swayni), 1.6% Greater kudu (T. sterepsiceros), 11% cattle and 1.6% domestic goats. The socia-economic survey confirmed that 250 households settled at eight villages in the Nechisar plains comprising 1640 Gllj'i Oromo people and 7080 livestock. The present study indicated that the Burchell's zebra population is at conservation risk because of the human impact that includes settlement encroachment, overgrazing, recent bush invasion and human disturbance. Developing community based wildlife conservation, improving the socio-economic standard and implementation of effective educational program to the loati people can serve as a tool for the population management of the Burchell's zebra.
A Comparative Study of Four Indigenous Cattle Breeds for Tick Resistance and Tick- Borne Diseases in Ghibe Valley
(Addis Ababa University, 2003-06) Feleke Adey; Petros Beyene (PhD)
The purpose of the study was to obtain information on the resistance levels of four indigenousbreeds of cattle (Abigar, Gurage, Horro and Sheko) to natural infestation with ticks in theGhibe Valley. Monthly collection of ticks from randomly selected cohort of 15 heifers ofeach breed, in the period January through October 2002, showed the most common tickspecies to be: Amblyomma variegatum (39.5%), Boophilus decoloratus (39.1%), A. cohaerens(10.5%) and Rhipicephalus evertsi evertsi (6.7%). Species of least abundance include, R.praetextatus, Haemaphysalis aciculifer, Hyalomma marginatum rufipes, R. bergeoni, R.lunulatus, R. muhsame and R. pravus, altogether comprising 4.2% of the overall tick species.The monthly abundance of adult and immature ticks, their feeding sites on the hosts and themale to female sex ratio were determined. Resistance to ticks between breeds was evaluatedbased on the cumulative log transformed counts of total ticks, fully engorged females andadult ticks and was analysed by the method of least squares. The results revealed that thecount of total ticks in Horro and Gurage (mean count of 5 ticks per month per breed) waslower than those of Abigar and Sheko (7 ticks per month per breed) (P< 0.001). The meancount of fully engorged females in Horro and Gurage cattle breeds was also lower (2 ticks permonth per breed) than Abigar and Sheko (3 ticks per month per breed) (P< 0.05). The meancount of adult ticks was the lowest in Horro (4 ticks per month per breed), followed byGurage (5 ticks per month per breed), Abigar and Sheko (6 ticks per month per breed) (P<0.01). Based on the three parameters, Horro and Gurage breeds were found to exhibitsignificantly higher resistance to ticks than Abigar and Sheko breeds. Packed Cell Volume(PCV) of the study animals was monitored monthly during the study period and negativecorrelation was found between tick burden and PCV levels in all the animals (P< 0.05).Infection with tick- transmitted parasites/ pathogens: Anaplasma marginale (84.2%), Babesiabigemina (87.1%) and Theileria mutans (54.2%) was confirmed serologically by indirect ELISA. Sera were also screened using indirect ELISA to investigate the animals for anti- Amblyomma variegatum antibody responses by using larval homogenate. Comparisons between antibody responses of each breed showed the presence of variations in IgG responses between the cattle breeds. Higher IgG response was found in Horro than the other three breeds (P< 0.05). The relationships between infestation with A. variegatum and the level of IgG were positive in Abigar (r = 0.3, P> 0.05), Gurage (r = 0.4, P< 0.05) and Sheko (r = 0.5,P< 0.05) breeds, while weak negative correlation (r = - 0.2, P> 0.05) was observed in Horro breed, indicating the possible role of IgG in the acquisition of host resistance to ticks.
Population Trend of Human, Livestock, Dog and Ethiopiian Wolf in Bale Mountains National Park,Ethiopia
(Addis Ababa University, 2004-06-03) Tilahun, Gashaw; Williams, Stuart (PhD)
Populations of human, livestock,dog and Ethiopian wolf were censused in the two study in the Afroalpine ecosystem of Bale Mountains National Park 9BMNP0, southern Ethiopia, during February-june 2003 using established road counts in Sanetti and horse back census in Kotera (Lower Web Valley). Data collected since 1998 were examined to indicate trends in the Populations. Census data were interpreted using encounter rates (as relative index of abundance) to analyze and understand spatial as well as temporal abundance of large mammals. They were more abundant in Kotera study site than in Sanetti Plateau. This was indicative of the Presence of spatial variation in the Afroalpine ecosystem in thisNational Park. Over the past six years, the population of livestock in Sanetti was increased which indicates the growing density of domestic animals in the area. The trend was negative in Kotera. Seasonal variation of the Afroalpine use by domestic animals was commonly observed in the BMNP. Domestic animals were more abundant during the wet season. A greater number of sightings were the areas in which Ethiopian wolves were also sighted more often. In contrast, in Sanetti , most of the livestock were distributed in Helichrysum meadoew and then in Erca moorland vegetation type. The Ethiopian wolves in this study site were tended to utilize Alpine grass meadow followed by Helichrysum meadow. The present study did not reveal any significant effect of livestock on the Ethiopian Wolves.

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