The emergence and spread of multidrug-resistant microbes become a serious threat to animal and human health globally because of their less responsiveness to conventional antimicrobial therapy. Multidrug-resistant microbial infection poses higher morbidity and mortality rate with significant economic losses. Currently, antimicrobial peptides and the CRISPR/Cas9 system are explored as alternative therapy to circumvent the challenges of multidrug-resistant organisms. Antimicrobial peptides are small molecular weight, cationic peptides extracted from all living organisms. It is a promising drug candidate for the treatment of multidrug-resistant microbes by direct microbial killing or indirectly modulating the innate immune system. The CRISPR/Cas9 system is another novel antimicrobial alternative used to manage multidrug-resistant microbial infection. It is a versatile gene-editing tool that uses engineered single guide RNA for targeted gene recognition and the Cas9 enzyme for the destruction of target nucleic acids. Both the CRISPR/Cas9 system and antimicrobial peptides were used to successfully treat nosocomial infections caused by ESKAPE pathogens, which developed resistance to various antimicrobials. Despite, their valuable roles in multidrug-resistant microbial treatments, both the antimicrobial peptides and the CRISPR/Cas systems have various limitations like toxicity, instability, and incurring high manufacturing costs. Thus, this review paper gives detailed explanations of the roles of the CRISPR/Cas9 system and antimicrobial peptides in circumventing the challenges of multidrug-resistant microbial infections, its limitation and prospects in clinical applications.

A cross-sectional study was conducted between December, 2013, and May, 2014, to determine the prevalence and antibiotic resistance feature of Salmonella isolated from broilers slaughtered in Debre Zeit and Modjo towns, Ethiopia. A total of 384 caecal content samples were collected for microbiological examination following the standard techniques and procedures outlined by the International Organization for Standardization to isolate Salmonella. The sensitivity of the isolates subjected to nine antimicrobials was tested by the Kirby–Bauer disk diffusion method. The overall prevalence of Salmonella was 14.6%, and its occurrence differ significantly by farm (p<0.05). The occurrence of the bacteria was not statistically different in the midland (15.2%) and lowland (13.3%) (p>0.05) and between males (13.5%) and females (15.6) (p>0.05). Of the 50 isolates, 48 were resistant to at least one drug. Multidrug resistance was recorded in 43 (86.0%) of the isolates. The study demonstrated considerable prevalence and high antimicrobial resistant Salmonella in exotic chicken and indicates the potential importance of chickens as source of foodborne salmonellosis and multiple antimicrobial resistance of Salmonella. Improving the hygienic practice of farms could help to reduce the occurrence of Salmonella in farms. Further studies are needed to describe the risk factors associated with the emergence of drug-resistant Salmonella in chicken.

Introduction: Pneumonic pasteurellosis mainly caused by bacterial species of Mannheimia, Pasteurella, and Bibersteinia causes a significant financial loss to the sheep production sector through reduced productivity and high mortality. There is a dearth of information on the major agents involved in the disease in the Amhara region, Ethiopia. Therefore, the aim of this study was to isolate and molecularly confirm Mannheimia, Pasteurella, and Bibersteinia from nasal swabs of sheep suspected of pneumonic pasteurellosis in selected areas of the Amhara region. Methods: Isolation and phenotypic characterization were performed using microbiological and biochemical testing according to standard methods. Molecular confirmation of isolates was done through amplification of virulence associated genes, PHSAA and Rpt2, of Mannheimia hemolyticausing multiplex PCR. Results: Accordingly, 46 out of 141 (32.62%) samples were presumably identified as M. hemolytica with no Pasteurella multocida and Bibersteinia trehalosi. Seven (n=7) out of the 46 isolates tested positive for either of the two virulence genes. Discussion and conclusion: The finding of this study is indicative that M. hemolytica is the main bacteria linked with pneumonic pasteurellosis in the study area which suggests the need to develop a polyvalent vaccine including strains of M. hemolytica or its antigenic determinants. However, the role of other bacterial, viral, and parasitic agents in the cases investigated should also be considered.

Background: Salmonellosis is one of the most common food‐borne diseases in industrialised and developing countries. In recent year, an increase in antimicrobial resistance among different Salmonella serotypes has been observed.Objective: A cross‐sectional study was conducted to assess the prevalence and antimicrobial susceptibility of Salmonella isolated from local chicken eggs in four selected towns in Ethiopia.Methods: A total of 115 eggs were examined to detect Salmonella by using standard microbiological methods. The susceptibilities of the isolates to nine antimicrobials were tested by the Kirby–Bauer disk diffusion method.Result: The study revealed that of the 115 eggs examined, 22 (19.1%) were positive for Salmonella of which 14 (12.2%) and 8 (7%) of the isolates were from shells and contents, respectively. The occurrence of Salmonella in egg shells and content and between different altitudes did not differ significantly (p > 0.05). Most isolates were resistant to more than three antimicrobials with a high resistance to kanamycin, ampicillin, nalidixic acid, cotrimoxazole, oxytetracycline and chloramphenicol.Conclusion: The results indicate the potential importance of local chicken eggs as source of multiple antimicrobial‐resistant salmonellae and the need for proper cooking before consumption. Further studies are required to describe the epidemiology of Salmonella in various agroclimatic zones of Ethiopia.

Diarrheagenic Escherichia coli are a number of pathogenic E. coli strains that cause diarrheal infection both in animal and human hosts due to their virulence factors. A cross sectional study was conducted between November, 2016 and April, 2017 to isolate and molecularly detect pathogenic E. coli from diarrheic calves to determine the pathogenic strains, antibiogram and associated risk factors in Jimma town. Purposive sampling technique was used to collect 112 fecal samples from diarrheic calves. Conventional culture and biochemical methods were conducted to isolate E. coli isolates. Molecular method was followed to identify virulence factors of pathogenic E. coli strains. Antimicrobial sensitivity patterns of the isolates were tested using the Kirby–Bauer disk diffusion method. A structured questionnaire was also used to collect information from dairy farms and socio-demographic data. The overall isolation rate of E. coli in calves was 51.8% (58/112) (95% CI 42.0–61.0). The occurrence of the bacterium differed significantly by age, colostrum feeding time, amount of milk given per time and navel treatment (P < 0.05). Multivariable analysis revealed that the odds of being infected was significantly highest in calves which fed 1–1.5 L amount of milk per a time (OR 5.38, 95% CI 1.66–17.45, P = 0.005). The overall virulence genes detection rate was 53.5% (95% CI 40.0–67.0). Eleven (19.6%) of eaeA, 6 (10.7%) of Stx1 and 13 (23.2%) of Stx2 genes were detected from calves isolates. Except ciprofloxacillin, all isolates were resistant to at least one drug. Multi drug resistance was recorded in 68.0% (38/56) of calves isolates. Neomycin, 83.3% (25/30), followed by amoxicillin, 53.3% (16/30) were the highest resisted virulence genes. The study demonstrated considerable isolation rate, multiple antimicrobial resistant isolates and high resistant virulent genes in diarrheic calves. It also indicated that the potential importance of calves as source of pathogenic E. coli strains and resistant genes for human diarrhea infection. Improving the hygienic practice of farms and wise use of antimicrobials could help to reduce the occurrence of pathogenic E. coli in farms. Hence, further studies are needed to describe all virulent factors and serotypes associated with the emergence of drug resistant pathogenic E. coli strains in calves.

Background: Marek’s disease is a chicken lymphoproliferative viral illness. As new viruses emerge, vaccination immunity is being broken and hence pathogenecity assessment and vaccine evaluation related to the pathogen is critical for developing vaccine immunity in the field. Methods: An experimental investigation was conducted to determine the pathogenicity of field isolates against Marek’s disease in antibody-free chicks and to assess the protective efficacy of the Marek’s disease vaccination. The viral isolates in question were discovered during an outbreak investigation for a previous study. The pathogenicity and effectiveness trial used a complete random design. Results: In the pathogenicity trial, chickens inoculated with Bishoftu and Mojo field isolate had lower body weight 77.7± 3.757 and 78.15± 1.95 g at 10 dpi, respectively, when compared to un-inoculated controls, 89.85± 3.838 g at 10 dpi. Incidence of early mortality syndrome (35% and 25%), lymphoma (53.8% and 40%), and overall mortality (50% and 45%) between Bishoftu and Mojo isolates, respectively, was discovered. Vaccinations with Herpes virus of turkey challenged chickens were provided complete protection against Marek’s disease. Conclusion: Based on the findings in pathogenecity assessment experimental trials, Bishoftu and Mojo isolates were designated as virulent Marek’s disease viruses. Regular vaccinations with Herpes virus of turkey vaccine and supported by biosecurity measures in poultry farms are important to prevent the disease.