Incidence rate, risk factors, and bacterial causes of clinical mastitis on dairy farms in Hawassa City, southern Ethiopia.

Mastitis is the most common disease of dairy cattle worldwide, causing economic losses due to reduced yield and poor quality of milk. It is of particular concern in Ethiopia, where effective prevention and control practices are lacking. The objective of the present prospective longitudinal study was to estimate the incidence rate of clinical mastitis (CM), identify the risk factors, isolate the bacterial agents, and determine the risk of recurrence. For this purpose, a total of 217 lactating cows were followed up every two weeks from calving to drying off or the end of the study period. Of these, 79 (36.41%) developed CM, of which 23% had recurrent infections in the same or a different quarter. The overall incidence rate of CM was 83.72 (95% CI: 63.2-98.2) cases per 100 cow-years at risk. In the multivariable Cox regression model, the risk of CM was found to be significantly higher in multiparous cows (HR = 1.96; p = 0.03), in cows with a history of mastitis (HR = 2.04; p = 0.030), in cows that had severely keratinized teat end condition (HR = 7.72; p < 0.001) and in cows kept in poorly cleaned barns (HR = 1.89; p = 0.007). The pathogenic bacteria isolated from mastitis-positive cows were Staphylococcus aureus (28.1%), E. coli (21.1%), Bacillus spp. (14%), Streptococcus spp. (14%), coagulase-negative staphylococci (12.3%), non aureus staphylococci (5.3%), Enterobacter spp. (3.5%), Klebsiella spp. (1.8%), Corynebacterium spp. (1.8%), and Proteus spp. (1.8%). The high incidence rate of CM in the present study shows that the disease spreads rapidly and can be responsible for a significant economic loss to milk producers in the study area. Therefore, raising awareness among dairy farmers, early detection and treatment of cases, post-milking teat disinfection, improvement of the hygienic status of cows and barns, use of dry cow therapy, and culling of chronic cases are recommended as viable measures to prevent and control clinical mastitis in the study area.

Isolation, identification antimicrobial susceptibility and associated risk factors of Salmonella in semi-intensive poultry farms of Kafa zone, Southwest Ethiopia.

Salmonellosis is one of the major causes of poultry disease. The study aimed to isolate, identify, determine susceptibility and associated risk factors of salmonella specious in semi-intensive poultry farms of Kafa zone, southwest Ethiopia. A cross-sectional study was conducted on four purposively selected districts. Three farms were randomly selected per district and fecal samples were taken from a total of 302 chickens. Questionnaire was administered to farm owners and data was analyzed using STATA statistical software package. The overall prevalence of Salmonella enterica species in Kafa zone was 9.27% with Gimbo district 10.39%, Bita district 10.66%, Shishoende district 12% and Chena district 4%. Source of chickens, farm types and breed risk factors showed significant association (P < 0.05) with the disease prevalence. Having diarrhea and continuous farm systems significantly associated (P < 0.05). All isolates were 100% resistant to Oxtytetracycline and Ampicillin. Among 28 isolated Salmonella enterica species, 92.85% (n = 26) of them were showed multidrug resistance while 2 (7.14%) of them showed extensively drug resistance. Half of multidrug-resistant isolates were resistant to 5-6 antimicrobials, while 7.14% of isolates showed resistance to 7 antimicrobials. This study shows prevalence of Salmonella and its association with the breed, farm type, source of chicken and presence of diarrhea. A high antimicrobial resistance observed shows presence of concerns due to the emergence of Antimicrobial Resistance (AMR) in the poultry farms. Therefore, awareness should be created to the farmers on measures to avoid the risk factors of poultry disease and the occurrence of antimicrobials resistance in poultry farms.

Lungworm infection in small ruminants in Ethiopia: Systematic review and meta-analysis.

Lungworms are important parasitic nematodes of small ruminants that colonize the lower respiratory tract and cause high morbidity and economic loss throughout the world. This systematic review was conducted with the aim of estimating the pooled prevalence of lungworm infection in small ruminants in Ethiopia. Besides, it examines the predictors thought to be responsible for heterogeneity noted between the reports. The search databases used were PubMed, CAB direct, AJOL and Web of science. Eligible studies were selected based on predefined inclusion and exclusion criteria. Thirty two studies published between 2000 and 2016 were found eligible and data were generated on 14,257 small ruminants (12,310 sheep and 1947 goats). Predictors including the study area, type of small ruminants affected, parasitic species involved, a diagnostic test used, study design, management systems, breed, agroecology, and year article published were used as milestone of data extraction. The statistical tool employed were meta-analysis, univariable and multivariable meta-regression and Egger's and begg's statistics for sensitivity analysis. Accordingly, the estimated pooled prevalence of lung worm infection in small ruminants was 40.8% (95% CI: 36.1, 45.6) with a very high heterogeneity between the study reports (I2 = 96.5%). However, diagnostic test used and administrative States were the only two predictors identified to explain 15.5% of the explainable heterogeneity (R2 = 0.1545, tau2 unexplained = 0.6032, tau2 total = 0.7135) noted between studies. The reviewed studies showed that three genera of lungworms, namely Dictyocaulus filaria, Mullerius capillaris and Protostrogylus rufescens were prevalent both in sheep and goats in Ethiopia. Mixed infection with two or three species was reported in 4.4 to 48.6% of the total infected animals. Indeed this review is informative and provides a better picture on lungworm infection in Ethiopia; however, it is not exhaustively detailed as there was lack of clear data on the role of some important factors like age, flock size, management system and seasonal variation on lungworm infection. Thus, thorough epidemiological studies including all seasons are required for formulation of meaning full control strategies.

Occurrence of Escherichia coli O157:H7 in cattle feces and contamination of carcass and various contact surfaces in abattoir and butcher shops of Hawassa, Ethiopia.

BACKGROUND: Despite of the sanitation measures in municipal abattoirs to reduce contamination, Escherichia coli continues to be a health hazard. The present study was conducted on 150 apparently healthy slaughtered cattle at municipal abattoir and in 50 different butcher shops in Hawassa town, Ethiopia. The objectives of the study were investigating the occurrence and antimicrobial resistance of E. coli O157:H7 isolated from fecal samples, carcasses swab, contacts surfaces (swabs of meat handlers hands, knife and clothes of meat transporters) as well as from butcher shops (meat samples, swabs from cutting board swab, butcher men hand and knife surface). E. coli O157:H7 was isolated and identified using bacteriological culture, biochemical tests and Biolog identification system. All E. coli O157:H7 isolates were then checked for their antimicrobial susceptibility pattern using eleven selected antimicrobial discs. RESULTS: Of the entire set of 630 samples, 2.4% (15/630) (95% CI = 1.3-3.9%) were positive for E. coli O157:H7. When disaggregated by the sources of the samples, E. coli O157:H7 were prevalent in 2.8% (11 of 390) of the abattoir samples, of which 4.7% of the fecal sample and 2.7% of the carcass swabs. And E. coli O157:H7 were positive in 1.7% (4 of 240) of butcher shop specimens of which 2% of meat sample and 3.3% of Cutting board swabs. No statistically significant difference in the prevalence of E. coli 0157: H7 between sex, origin, and breed of cattle. The isolated E. coli O157:H7 were found to be100% susceptible to cefotaxime, ceftriaxone, gentamycin, kanamycin and nalidixic acid. CONCLUSION: This study concludes the occurrence of E. coli O157:H7 and the presence of multiple antibiotic resistance profiles in cattle slaughtered at Hawassa municipal abattoir and retail meat sold at butcher shops. This indicates high risk to public health especially in Ethiopia where many people consume raw or under cooked meat. Regulatory control of antibiotics usage in livestock production and pharmaco-epidemiological surveillance in food animals and animal products is hereby recommended to ensure consumer safety.

Bovine mastitis: prevalence, risk factors and isolation of Staphylococcus aureus in dairy herds at Hawassa milk shed, South Ethiopia.

BACKGROUND: Mastitis is a disease of major economic importance in dairy industry worldwide. It is of particular concern in developing countries like Ethiopia, where milk and milk products are scarce. The objectives of the study were to estimate the prevalence of mastitis, identify the cow-and herd-level potential risk factors and isolate Staphylococcus aureus, one of etiological agents for contagious mastitis, from cows positive for mastitis. A total of 529 lactating cows selected randomly from 95 herds were screened by California mastitis test (CMT) for sub-clinical mastitis. Also 172 milk samples collected from CMT positive cows were cultured for isolation of S. aureus. RESULTS: Based on CMT result and clinical examination, the prevalence of mastitis at herd-level was 74.7% (95% CI: 64.5, 82.8). The corresponding cow-level prevalence was 62.6% (95% CI: 58.3, 66.7), of which 59.2 and 3.4% were sub-clinical and clinical mastitis cases, respectively. S. aureus was isolated from 51.2% of the milk samples cultured and 73.2% of the herds affected with mastitis. In the multivariable logistic regression model, the herd-level factors significantly associated (p < 0.05) with the presence of mastitis were herd size, bedding material, and milking mastitic cows last, while at cow-level, breed, parity, stage of lactation, udder and leg hygiene, and teat end shape were noted to have a significant effect on mastitis occurrence. CONCLUSION: The very high prevalence of mastitis, more importantly the sub-clinical one, in the herds examined revealed the huge potential economic loss the sector suffers. Perhaps this was attributed to lack of implementation of the routine mastitis prevention and control practices by all of the herd owners. The findings of this study warrants the need for strategic approach including dairy extension that focus on enhancing dairy farmers' awareness and practice of hygienic milking, regular screening for sub-clinical mastitis, dry cow therapy and culling of chronically infected cows.

Microbial contamination of water intended for milk container washing in smallholder dairy farming and milk retailing houses in southern Ethiopia.

The water used during handling and processing of milk products can be potential sources of microbial contamination with possible negative consequences on food safety. Especially, the water used in keeping the hygiene of milking and milk storage utensils is crucial to keep the quality and safety of the products. Therefore, the current study was designed to assess the bacteriological quality of water used for cleaning milking and milk storage equipment in smallholder dairy production in Hawassa and its surroundings. A total of 79 water samples were collected: 26 from milk collecting houses in Hawassa and 53 from selected smallholder dairy farms (Hawassa = 14, Arsi Negele = 29 and Yirgalem = 10). Out of the total samples, 18 samples were collected directly from pipe and 61 from storage containers (46 from narrow opening and 15 from wide opening containers). The overall prevalence of E. coli exceeding zero CFU/ml was 39.2 %. From analyzed samples, high prevalence of positive samples for E. coli was found in water samples taken from wide opening containers (66.7 %). A number of bacteria were isolated and presumptively identified which include Bacillus sp. 6.3 % (n = 5), Citrobacter sp. 1.3 %(n = 1), E. coli 39.2 % (n = 31), Enterobacter sp. 2.5 % (n = 2), Klebisella sp. 7.6 % (n = 6), Micrococcus sp. 6.3 % (n = 5), Pseudomonas sp. 6.3 % (n = 5), Staphylococcus aureus 6.3 % (n = 5), Staphylococcus epidermidis 13.9 % (n = 11) and Streptococcus sp. 1.3 % (n = 1). The bacteriological quality of water especially, water stored in household storage containers in present study area was found to be contaminated with different bacteria indicating potential food safety problem and health risk to the society. In this respect, people handling water should be educated on its proper handling and the risk of contamination during storage. To minimize contamination, materials with narrow mouth and lid should be used. Further study is recommended on the relationship between the bacteriological quality of water and the behavior of water users.

Systematic review and meta-analysis of metacestodes prevalence in small ruminants in Ethiopia.

Metacestodes, the larval stages of canid cestode parasites, are among the causes of morbidity, mortality and financial losses in small ruminants in Ethiopia as a result of organ and carcass condemnation at slaughter. Several studies have been conducted over the years; however, these studies often had limited scope and coverage. This systematic review and meta-analysis was conducted to collate the information so far available in order to provide a pooled prevalence estimate at national level and identify potential predictors. Published and grey literature written in English and Amharic in the period from, 1st of January 1990 to June 25, 2015 were searched from electronic databases and repositories of academic and research institutions. Relevant animal level data on 67,743 small ruminants was extracted from 23 published articles and one master's thesis resulting altogether in 86 animal level reports that conformed to predefined criteria. The dataset was analyzed using a meta-analytical approach. The pooled prevalence estimate computed for metacestodes infection was 11.8% with a 95% confidence interval (CI) of 9.1, 15.4. The highest prevalence estimate 31.2% (95% CI: 23.1, 40.9) was found for Cysticercus tenuicollis (Taenia hydatigena) followed by cystic echinococcosis (Echinococcus granulosus) 8.8% (95% CI: 5.8, 13.1), Cysticercus ovis (Taenia ovis) 4.9% (95% CI: 2.9, 9.4) and Coenurus cerebralis (Taenia multiceps) 4.6% (95% CI: 1.6, 12.2). Among the predictors considered for heterogeneity analysis only sample size and metacestode type fitted the final multivariable meta-regression model and explained 26.3% of the explainable heterogeneity between studies (p<0.05). The prevalence was noted to decrease with increasing sample size. No significant difference in prevalence was observed between sheep and goats (p>0.05). In conclusion, this review showed a widespread occurrence of metacestodes in small ruminants in Ethiopia. Thus, a holistic approach to break the life cycle of these parasitic stages is suggested, including regulatory interventions that encourage dog owners to keep their dogs confined and prevent backyard slaughter and proper management of abattoir waste disposal.

Gastrointestinal nematode infection in small ruminants in Ethiopia: A systematic review and meta-analysis.

Gastrointestinal (GI) nematode infections are a major health challenge affecting productive and reproductive performance of sheep and goats in Ethiopia. However, there is no comprehensive summary on the occurrence and distribution of the infection at national level. This systematic review provides pooled prevalence estimates and assesses potential predictors of the nematode infections in small ruminants, i.e. helpful in planning interventions or control strategies. The review used 50 animal level datasets retrieved from 24 manuscripts. The studies used data collected from 9407 sheep and 3478 goats. A meta-analytical approach was employed to analyze Effect size (ES). The reported GI nematodes represented eleven genera affecting sheep and goats including: Haemonchus, Trichostrongylus, Teladorsagia/Ostertagia, Strongyloides, Bunostomum, Nematodirus, Chabertia, Trichuris, Cooperia, Skrjabinema and Oesophagostomum. The GI nematodes pooled prevalence estimate in the random effect model was 75.8% (95% CI: 69.6, 80.8). The subgroup analysis revealed significant (p<0.05) differences in the prevalence between different regions and type of diagnostic methods used. 'Postmortem technique' and 'eastern part of the country' were associated with higher GI nematode prevalence and accounted for 68.1% of the between studies heterogeneity. In light of the high parasitic prevalence in all agro-ecologies, the need for strategic intervention is recommended. Meanwhile, data need to be generated for some of the regions where dependable survey reports are lacking.

Bovine trypanosomosis and Glossina distribution in selected areas of southern part of Rift Valley, Ethiopia.

Cross-sectional study was conducted in 9 selected districts of the southern part the Rift Valley, Ethiopia to estimate the dry period prevalence of bovine trypanosomosis as well as assessment of Glossina species. From a total of 1838 cattle examined for trypanosomosis by buffy coat technique 133 (7.2%) were found infected by trypanosome species. From the total positive animals 66.9 and 33.1% of them accounted to Trypanosoma congolense and Trypanosoma vivax, respectively. Significantly higher prevalence (19.4%., P<0.05) was recorded at Arba-Mnch district. Black colored cattle were the most highly affected (χ(2)=79.35, P<0.05) animals. The overall average PCV value for parasitaemic and aparasitaemic animals was 22.2 (95% CI=21.6-22.7) and 27% (95% CI=26.8-27.2), respectively. The fly caught per trap per day was 1.4 for Glossina species and 2.8 for other biting flies. Two species of Glossina identified namely Glossina pallidipes and Glossina fuscipes.

Major causes of mastitis and associated risk factors in smallholder dairy farms in and around Hawassa, Southern Ethiopia.

A cross-sectional study was carried out from October 2008 to May 2009 in smallholder dairy farms in and around Hawassa to estimate the prevalence of mastitis, to isolate and characterize major bacterial pathogens, and to identify possible associated factors. The study involved a total of 201 milking cows randomly drawn from smallholder farms. The prevalence of clinical and subclinical mastitis was determined through clinical examination of the udder and using mastitis indicator paper (Bovivet indicator paper, Kruuse, Denmark). The prevalence of mastitis at cow and quarter level was 30.3 (61/201) and 10.3 (79/766), respectively. Subclinical mastitis was 25.4% and 5.0% was clinical. Stage of lactation significantly affected (P < 0.05) the prevalence of mastitis, with the highest prevalence observed in the late stage of lactation (41.3%) as compared to early (25.0%) and mid (22.1%) stages of lactation. Floor type and bedding had association (P < 0.05) with mastitis prevalence. Cows housed in concrete-floored houses had lower prevalence (19.0%) of mastitis compared to cows kept in soil-floored houses (47.6%). Mastitis prevalence was low in farms which do not use bedding (23.5%) as compared to farms using hay/straw bedding (37.4%). However, age, parity, and history of mastitis had no association (P > 0.05) on the prevalence of mastitis. The pathogens isolated from mastitic cows were Staphylococcus aureus (48.6%), other staphylococci species (15.7%), Streptococcus agalactiae (11.4%), other streptococci (17.1%), Bacillus species (2.9%), and coliforms (Escherichia coli and Klebsiella species) (4.3%). Strict hygienic measure of housing and bedding should be considered, in reducing the prevalence of mastitis.

Survey of ixodid ticks in domestic ruminants in Bedelle district, Southwestern Ethiopia.

A survey aimed at determining the status of ticks in cattle, sheep and goats in Bedelle district (Southwestern Ethiopia) was carried out from November 2007 to April 2008. Out of the total 330 animals examined, 314 (95.2%) were found to be infested (harbouring of at least a single tick). High rates of infestations were recorded across all three host species. Factors like month of collection, age and sex of host species did not show significant association with infestation rates. A total of 5,507 ticks belonging to three genera (i.e. Amblyomma, Boophilus and Rhipicephalus) were collected during the study period of which six species were identified. The species of ticks encountered comprise of Amblyomma cohaerens (44.1%), Amblyomma variegatum (13.8%), Amblyomma lepidum (1.2%), Boophilus decoloratus (24.9%), Rhipicephalus evertsi evertsi (14.3%) and Rhipicephalus lunulatus (1.7%). As about 86.7% (4,772) of the ticks were collected from cattle, it was recognised that this could be an evidence of host preference where cattle are serving as principal host while sheep and goats serve as alternative hosts. The role of ecological factors and little attention paid by livestock owners for treatment of animals against ticks are suggested to result in the abundance of ticks. Acaricide spraying should be strategically applied to control ticks. Better result could be achieved if an emphasis is being put on spraying cattle. Studies on tick-borne diseases, involvement of wildlife species as well as related factors are recommended as they may provide a valuable basis for designing and launching an all-round control programme in the country.