Alemayehu Regassa

Bovine fasciolosis: coprological, abattoir survey and its economic impact due to liver condemnation at Soddo municipal abattoir, Southern Ethiopia

A study was carried out to determine the prevalence and the species of liver flukes in indigenous adult cattle, to compare the diagnostic efficiency of fecal and post mortem examination and to assess the economic significance of bovine fasciolosis due to liver condemnation in the abattoir. Of the 406 livers and fecal samples examined, 57 (14.0%) and 20 (4.9%) were positive for fasciolosis. The most common liver fluke species affecting the cattle was Fasciola gigantica, 9.1% of cattle were infected with F. gigantica while, Fasciola. hepatica, mixed infections and unidentified or immature forms of Fasciola spp. were present in 3.2 %, 0.7% and 1 % of cattle, respectively. A retrospective abattoir survey revealed that the prevalence of fasciolosis was 12.7%. The prevalence of fasciolosis recorded in this study was lower than that reported by other researchers in this country. There was a strong relationship between fecal examination and postmortem findings of liver lesions, (K = 0.23) but under local conditions, postmortem examination was considered a better diagnostic tool for fasciolosis. Fasciolosis is of significant economic importance as the resultant liver condemnations caused an average loss of 4000 USD per annum. Hence, this disease deserves serious attention by the various stakeholders in order to promote the beef industry in the study area in particular and in the country in general.

Seroprevalence of brucellosis and its contribution to abortion in cattle, camel, and goat kept under pastoral management in Borana, Ethiopia

The involvement of Brucella infection in causing abortion was investigated in a breeding female subpopulation of 283 cattle, 756 camels, and 757 goats. Serum samples were serially tested using the Rose Bengal test and complement fixation test. The study showed that anti-Brucella antibodies were prevalent in 10.6% (95% confidence interval (CI), 7.4, 14.9), 2.2% (95%CI, 1.4, 3.7), and 1.9% (95%CI, 1.1, 3.2) of cattle, camel, and goats, respectively. Abortion was more commonly reported in camels (23.4%) than cattle (13.8%) and goats (12.4%). The results of this study suggested that Brucella infections contribute significantly to abortion in cattle (odds ratio (OR), = 4.7; 95%CI, 2.0, 10.8) and goats (OR = 6.9; 95%CI, 2.2, 21.7) but not in camels. The number of young animals produced by breeding females seems to be apparently reduced in seropositive groups. Keeping more than two animal species at household level was found to be the risk factor for cattle (OR = 3.1; 95%CI, 1.2, 7.9) and camel (OR = 5.3; 95%CI, 1.2–23.5) seropositivity to Brucella infection when compared to those animals from households that keep only two animal species. This may suggest a possibility of cross species transmission of Brucella infection under such mixed herding. Wet season (OR = 4.8; 95%CI, 1.3, 18.1) was found to be associated with seropositivity in goats, linked to a coincidence of increased deliveries in flocks with possible excretion of Brucella organisms. The study results suggest that Brucella infection is the likely cause of abortion in cattle and goats while other causes largely outweigh brucellosis as a cause of abortion in camels in Borana, hence, contributing to reproductive loss.

A cross-sectional study on bovine tuberculosis in Hawassa town and its surroundings, Southern Ethiopia

A cross-sectional study was conducted in Hawassa town and its surroundings from October 2007 to May 2008 to estimate the prevalence of bovine tuberculosis (BTB) based on comparative interadermal tuberculin test (CIDT) and abattoir survey. Accordingly, 39 herds comprising 413 cattle were subjected to CIDT, and the herd and individual animal prevalence were 48.7% (19/39) and 11.6% (48/413), respectively. One of the 16 milk samples collected from tuberculin-positive cows was culture positive. The prevalence significantly differed among the age group (P = 0.001) and management system (P = 0.001). Thus, age group over four (OR = 7.9) and animal with poor management system (OR = 4.1) had a higher odds for tuberculin reactivity compared to those with age group under four and cattle with good management system, respectively. Of the total 1,023 cattle subjected to postmortem examination, 11 (1.1%) were found to be positive for gross tuberculous lesions. Larger proportion (50%) of TB lesion was recorded in the respiratory pathway followed by digestive system (28.6%) and prescapular lymph nodes (21.4%). Of 14 tissue specimens collected from the gross lesions, four (28.6%) were positive for histopathological TB lesions. In conclusion, this study revealed the importance of BTB in the study area in particular and the region in general.

Bovine Cysticercosis in Cattle Slaughtered at Awassa Municipal Abattoir, Ethiopia: Prevalence, Cyst Viability, Distribution and its Public Health Implication

A cross‐sectional study was conducted from October 2005 to April 2006 on bovine cysticercosis in cattle slaughtered at Awassa municipal abattoir with the objective of determining the prevalence of Taenia saginata cysticercosis, cyst viability, distribution and its public health implication. Questionnaire survey involving 120 respondents was also conducted on human taeniasis. A total of 400 carcasses were examined during the study period, of which 105 (26.25%) were infected with T. saginata metacestodes. From a total of 3200 samples inspected, 500 cysticerci were detected in 141 samples, of which 221 (44.2%) were alive. The anatomical distribution of cysticerci were 65 (29.2%) heart, 56 (25.3%) shoulder muscle, 59 (26.7%) masseter, 23 (10.4%) tongue, 12 (5.4%) diaphragm, three (1.4%) liver, two (0.9%) lung and one (0.5%) kidney samples. The prevalence varied significantly between local and crossbred animals (OR = 3.15, P < 0.05), but not varied between sex, age groups and origin of the animals. T. saginata taeniasis was a widespread public health problem in the town with an overall prevalence of 64.2% (77 of 120). The potential risk factors for disease contraction were raw meat consumption, religion and occupational risks. In conclusion, the study revealed high prevalence of T. saginata metacestodes throughout the edible organs together with existence of deep‐rooted tradition of raw meat consumption. This may magnify the public health hazards of T. saginata in the study area. As a result, the disease deserves due attention to safeguard the public health and further promote beef industry in the country.

Major metacestodes in cattle slaughtered at Wolaita Soddo Municipal abattoir, Southern Ethiopia: Prevalence, cyst viability, organ distribution and socioeconomic implications

A cross sectional study to determine the prevalence and socioeconomic importance of major metacestodes of cattle was conducted from November 2007 to April 2008 at Wolaita Soddo abattoir. Accordingly, of 415 randomly selected slaughtered cattle, 11.3% and 15.4% were infected with Cysticercus bovis and hydatid cysts, respectively. The anatomical distributions of these parasites include various organs. The major risk factors for cysticercosis prevalence were origin of the animals (P < 0.001, OR = 7.3) and breeds (P = 0.004, OR = 4.3), and hydatid cysts prevalence was significantly varied with different origins (P = 0.021, OR = 2.8). The viability of C. bovis was higher (28.3%) than that of hydatid cyst (1.7%). Of 79 interviewed respondents, 50.63% had acquired taeniasis and analysis of the risk factors showed association of religions (P = 0.003, OR = 24.4), occupation (P < 0.001, OR = 6.9), educational background (P = 0.035, OR = 2.7) and age (P < 0.001, OR = 3.9) of the respondents with taeniasis prevalence. Furthermore, the inventory of taeniasis drugs dose and treatment cost were estimated to be 335,772 adult doses and 93,310 USD. In conclusion, the findings of the present study imply the zoonotic and socioeconomic importance of the diseases, which need intervention.

Occurrence of mastitis and associated risk factors in lactating goats under pastoral management in Borana, Southern Ethiopia

Mastitis prevalence and related risk factors were studied in 1,072 udder halves of 536 lactating goats from October, 2008 to February, 2009. Clinical and subclinical mastitis were prevalent in 4.3% (95% CI = 2.8, 6.5) and 11.2% (95% CI = 8.7, 14.3) of the studied animals, respectively, resulting in an overall prevalence of 15.5% (95% CI = 12.6, 18.9). Univariate analysis of the potential risk factors has depicted that mastitis was more prevalent in does with previous mastitis history, increased parity, poor body conditions, increased milk production, late lactation stage, long teat, and housed goats. Furthermore, prevalence was significantly higher (p < 0.05) during the wet period of October to November than the dry periods of January to February. No significant variations (p > 0.05) were observed in mastitis prevalence with udder tick infestation, mixing goat with sheep and flock size. With multivariable analysis, lactation stage, teat length, body condition, and season (wet months) have showed significant association with mastitis prevalence, and these factors maintained significant in the stepwise elimination of multivariable logistic regression model. As a result, does in late stage of lactation (OR = 4.3, 1.8, 10.4), poor body condition (OR = 5.0, 1.7, 10.0), long teats (OR = 2.2, 95% CI = 1.1, 4.2) and does examined in wet period were at higher risk of udder infections than early lactation, good body condition, short teat, and examined in dry period, respectively. The study showed occurrence of mastitis and associated risk factors in studied goats, which suggests the need for control intervention. Further investigations into pathogens involved in goat mastitis will optimize our knowledge of causative agents and control interventions.

Fasciolosis: Prevalence, financial losses due to liver condemnation and evaluation of a simple sedimentation diagnostic technique in cattle slaughtered at Hawassa Municipal abattoir, southern Ethiopia

An abattoir survey was carried out in Mekelle municipal abattoir, Ethiopia to determine the prevalence of concurrent infections of hydatidosis and fasciolosis in cattle. A total of 4,481 slaughtered cattle were studied by ante- and post-mortem examinations. From the total 4,481 slaughtered cattle examined at Mekelle municipality abattoir, 357 (8%) were found to harbor mixed infection of hydatidosis and fasciolosis. While the individual prevalence of hydatidosis and fasciolosis was 32.11% and 24.32%, respectively. Multivariate logistic regression analysis indicated that among the factors considered in the current study, origin of animals had statistically significant ffect on the prevalence of concurrent infection (OR = 1.418, 95% CI = 1.108 - 1.814, p = 0.005), whereas breed and body condition of animals didn’t have significant effect on prevalence of the co-infection. Moreover, month had no statistically significant effect on prevalence of hydatidosis and fasciolosis co-infection (OR= 1.0029, 95% CI = 0.9758 - 1.0306, p = 0.867). Generally this study showed that hydatidosis and fasciolosis are important disease problems in cattle in the study area. The relatively higher prevalence in the occurrence of the concurrent infection of hydatidosis and fasciolosis in this study may suggest that ecological factors that determine the occurrence of the two diseases might be similar. On the other hand, the higher prevalence of the individual or concurrent infection may imply that these diseases have the potential to cause considerable economic and public health problems. Keywords: Coinfection, Fasciolosis, Hydatidosis, Mekelle, Prevalence.

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

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

Seroepidemiological study of livestock brucellosis in a pastoral region

A seroepidemiological study of Brucella infections in multiple livestock species in the Borana pastoral system of Ethiopia was performed between December 2007 and October 2008. A cross-sectional multi-stage sampling technique was employed to select 575 cattle, 1073 camels and 1248 goats from the target populations. Sera were collected from the animals, and serially tested using Rose Bengal test and complement fixation test. Overall prevalence and prevalence with respect to explanatory variables were established, and potential risk factors for seropositivity were analysed using a multivariable logistic regression. The results showed that 8·0% (95% CI 6·0-10·6), 1·8% (95% CI 1·1-2·8) and 1·6% (95% CI 1·0-2·5) of the tested cattle, camels and goats, respectively, had antibodies to Brucella antigen. Positive reactors were found in 93·8% of the villages with more frequent detection of positive cattle (93·3%) than camels (56·3%) and goats (37·5%). Risk factors identified for cattle were: keeping more livestock species at household level (OR 4·1, 95% CI 1·9-8·9), increasing age of the animal (OR 2·8, 95% CI 1·3-6·0) and wet season (OR 3·3, 95% CI 1·6-6·9). Increase in household-level species composition (OR 4·1, 95% CI 1·2-14·2) and wet season (OR 3·7, 95% CI 1·5-9·1) were found to be risk factors for seropositivity in camels and goats, respectively. Existence of more than one seroreactor animal species in most villages and association of increased livestock species composition with seropositivity may add more credence to the possibility of cross-species transmission of Brucella infections. Although no attempt to isolate Brucella spp. was made, our results suggest that cattle are more likely maintenance hosts of Brucella abortus which has spread to goats and camels. This should be substantiated by further isolation and identification of Brucella organisms to trace the source of infection and transmission dynamics in various hosts kept under mixed conditions. In conclusion, the present study suggests the need for investigating a feasible control intervention and raising public awareness on prevention methods of human exposure to brucellosis.

Survey of tick infestation in small ruminants of Miesso district, West Harergie, Oromia Region, Ethiopia

AbstractA survey was conducted to identify tick species and determine the prevalence of tick infestation in small ruminants of Miesso District, West Harergie Zone. Collection and identification of the ticks were undertaken from November 2007 to April 2008. All visible individual adult ticks were collected from the body of 328 goats and 40 sheep. The prevalence of tick infestation in goats and sheep was found to be 89.9% and 87.5%, respectively. In this study, ten species of ticks which grouped under four genera were identified. The most abundant species found in this study were Boophilus decoloratus (60%), Rhipicephalus pulchellus (25.1%), and Amblyomma gemma (11%). Hyalomma dromedarii was the minor species observed on goats. The difference in the prevalence of tick infestation between sheep and goats was not statistically significant (Χ2  = 0.22, p = 0.63) but found to be statistically significant between male and females (Χ2 = 9.8, p = 0.003). Attention should be given to the control and prevention of ticks, since they cause sever damage to the skins of small ruminants and thereby reduce the foreign exchange of the country; they also transmit some diseases which can cause sever loss to the productivity of these animals.