Antibiotic resistance of Staphylococcus aureus isolates from milk produced by smallholder dairy farmers in Mbeya Region, Tanzania

Research (Published online: 28-03-2019)

5. Antibiotic resistance of Staphylococcus aureus isolates from milk produced by smallholder dairy farmers in Mbeya Region, Tanzania

H. F. Massawe, R. H. Mdegela and L. R. Kurwijila

International Journal of One Health, 5: 31-37

ABSTRACT

Aim: The study determined and evaluated the prevalence and antibiotic resistance of Staphylococcus aureus isolated from milk collected along the milk value chain from farm herds, milk collection center, and milk shops in Mbeya rural and Mbozi districts, Tanzania.

Materials and Methods: A total of 150 milk samples were collected; 96 from farmers' herds, 18 from milk collection centers, and 36 from milk shops. The samples were cultured in Mannitol salt agar for pathogen isolation and biochemical tests performed for confirmation of S. aureus. Kirby-Bauer disk diffusion method was employed for antibiotic resistance testing.

Results: One hundred and forty samples yielded Staphylococcus species; these were from farmer's herd (92), milk collection center (18), and milk shops (30), respectively. Biochemical tests showed that 21 (15%) were positive for S. aureus. The corresponding prevalence rates from the value chain nodes were 14.1%, 16.7%, and 16.7%, respectively. Resistance to penicillin was frequently observed (57.1%) and vancomycin was sensitive to all S. aureus isolates tested. Resistance along the sampling points showed a significant positive correlation (r=0.82, p<0.0001; r=0.65, p<0.003; and r=0.61, p<0.01) between farmers, milk collection points, and milk shops, respectively. More than half (57.1%) of the isolates exhibited resistance to three or more of the antibiotics used in this study. S. aureus isolates were shown to have a multiple antimicrobial resistance patterns, particularly with respect to penicillin, ampicillin, erythromycin, and tetracycline.

Conclusion: The level of staphylococcal isolates and the antibiotic resistance of S. aureus found in this study is an indication of subclinical mastitis, poor hygiene, and inappropriate use of antibiotics; therefore, education of farmers on subclinical mastitis control and proper use of antibiotics would be of benefits in these areas.

Keywords: milk contamination, milk products, multiple antibiotic resistant.

Extended-spectrum β-lactamase-producing Escherichia coli in chickens from small-scale (backyard) poultry farms in Maiduguri, Nigeria

Research (Published online: 27-03-2019)

4. Extended-spectrum β-lactamase-producing Escherichia coli in chickens from small-scale (backyard) poultry farms in Maiduguri, Nigeria

Iliya Dauda Kwoji, Jasini Athanda Musa, Nubwa Daniel, Dauda Luka Mohzo, Asinamai Athliamai Bitrus, Abiodun Andrew Ojo and Kingsley Uwakwe Ezema

International Journal of One Health, 5: 26-30

ABSTRACT

Aim: This study investigated the occurrence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in chickens from small-scale (backyard) commercial poultry farms in Maiduguri.

Materials and Methods: A total of 96 cloacal swab samples were collected. This comprised of 24 samples each from broiler chicks, pullets, layers, and broilers (adults). The samples were examined for the presence of E. coli using conventional microbiological culture and biochemical tests. The pure E. coli isolates were screened for ESBL production by culturing onto BrillianceTM ESBL agar. Isolates that showed positive reactions with production of bluish or pinkish colonies were tested for susceptibilities against some selected β-lactam antibiotics which include cefotaxime (30 μg), ceftriaxone (30 μg), cefpodoxime (10 μg), aztreonam (30 μg), and ceftazidime (30 μg). Isolates that exhibited resistance to any two or three of the antibiotics were selected and confirmed by combination disk diffusion method with ceftazidime (30 μg) and cefotaxime (30 μg) alone and in combination with clavulanic acid (30 μg/10 μg).

Results: The total occurrence of E. coli was 67.6% (65/96) with the highest occurrence of 83.3% (20/24) from broiler chicks and least detection of 54.2% (13/24) from layers. Of this, 32.0% were ESBL-producing E. coli with the highest detection rate from layers (38.5%) and least occurrence from pullets (26.7%).

Conclusion: This study revealed the presence of ESBL-producing E. coli in chickens from small-scale commercial poultry farms in Maiduguri, thus indicating that chickens may serve as important reservoirs for the transmission of antimicrobial resistant pathogens to humans through the food chain.

Keywords: antimicrobials, chickens, extended-spectrum beta-lactamase, Escherichia coli, Maiduguri.

Influence of some parameters on the ability of Listeria monocytogenes, Listeria innocua, and Escherichia coli to form biofilms

Research (Published online: 26-03-2019)

17. Influence of some parameters on the ability of Listeria monocytogenes, Listeria innocua, and Escherichia coli to form biofilms

Sara Lezzoum-Atek, Leila Bouayad and Taha Mossadak Hamdi

Veterinary World, 12(3): 459-465

Aim: The present study was conducted to evaluate the capacity of Listeria monocytogenes (L.m), Listeria innocua (L.i), and Escherichia coli to form biofilms on polystyrene support under different parameters by performing crystal violet (CV) staining technique.

Materials and Methods: Different suspensions were prepared with single strains and with multiple combinations of strains including two serogroups of L.m (IIa and IIb), L.i, and E. coli strains at different microbial load. Selected strains and combinations were grown in biofilms for 6 days attached to polystyrene microplates under aerobic and microaerophilic conditions. The evaluation of the power of adhesion and biofilm formation was determined by CV staining followed by the measurement of optical density at 24 h, 72 h, and 6 days incubation time with and without renewal of the culture medium.

Results: All the strains tested, presented more or less adhesion power depending on the variation of the studied parameters as well as the ability to form multispecies biofilms. Their development is more important by renewing the culture medium and increasing the initial load of bacteria. The ability to adhere and form biofilms differs from one serogroup to another within the same species. In bacterial combination, strains and species of bacteria adopt different behaviors.

Conclusion: The ability to form biofilms is a key factor in the persistence of tested strains in the environment. Our study showed that L.m, L.i, and E. coli could adhere to polystyrene and form biofilms under different conditions. More researches are necessary to understand the mechanisms of biofilm formation and the influence of different parameters in their development.

Keywords: biofilm, Escherichia coli, Listeria innocua, Listeria monocytogenes, polystyrene support, variation of parameters.

Clinical-histopathological and molecular study of ovine pulmonary adenocarcinoma in Awassi sheep in Al-Qadisiyah Province, Iraq

Research (Published online: 26-03-2019)

16. Clinical-histopathological and molecular study of ovine pulmonary adenocarcinoma in Awassi sheep in Al-Qadisiyah Province, Iraq

Khalefa Ali Mansour, Saad Hashim Al-Husseiny, Qassim Haleem Kshash and Asaad Jassim

Veterinary World, 12(3): 454-458

Aim: This study aimed to conduct a clinical-histopathological and molecular evaluation of ovine pulmonary adenocarcinoma (OPA) in Awassi sheep in various regions of Al-Qadisiyah Province, Iraq.

Materials and Methods: A total of 150 sheep were clinically evaluated, and the wheelbarrow test was performed. 100 samples (35 blood, 25 lung tissue, 20 lymph node, and 20 lung fluid samples) were randomly selected from living and slaughtered sheep. All samples were subjected to polymerase chain reaction (PCR). Histopathological examinations were performed for four lung tissue and two lymph node samples.

Results: A diagnosis of OPA was made based on the results of the clinical examination and the clinical signs shown by the animals, such as dyspnea, polypnea, coughing, mucous nasal discharge, moist rales on auscultation of the affected lungs, and emaciation. Interestingly, the animals tested positive for the wheelbarrow test, with frothy nares accompanied by profuse and clear lung fluid. Histopathological examination showed various lesions such as glandular transformation in the lung tissues and emphysema. Moreover, lymph nodes showed marked follicular atrophy and necrosis-associated lymphocyte infiltration in the affected tissues. PCR revealed that 25% of the samples including eight (22.8%) blood, five (20%) lung tissue, five (25%) lymph node, and seven (35%) lung fluid samples were positive for Jaagsiekte sheep retrovirus; this result was highly significant.

Conclusion: The results of our study indicated that in Iraq, OPA diagnosis should be based on pathological findings and results of advanced procedures such as PCR.

Keywords: Jaagsiekte sheep retrovirus, ovine pulmonary adenocarcinoma, polymerase chain reaction.

Stability of hematological parameters of canine blood samples stored with citrate phosphate dextrose adenine-1 anticoagulated plastic vacutainers

Research (Published online: 25-03-2019)

15. Stability of hematological parameters of canine blood samples stored with citrate phosphate dextrose adenine-1 anticoagulated plastic vacutainers

Okereke Henry Nnamdi, Udegbunam Rita Ijeoma and Nnaji Theophilus Okaforx

Veterinary World, 12(3): 449-453

ABSTRACT

Aim: The effect of citrate phosphate dextrose adenine-1 on the hematological parameters of stored Nigerian indigenous dog's blood with plastic vacutainer was investigated. This was done in view of determining the viability and stability of the studied parameters for blood banking purpose. Till date, there is no literature on the stability of whole blood of Nigerian indigenous dogs for blood banking purposes.

Materials and Methods: A total of six apparently adult healthy dogs were sampled, and their blood was stored at 4°C and analyzed for their packed cell volume (PCV), hemoglobin (Hgb) concentration, red blood cell (RBC) count, total and differential white blood cell (WBC) count, platelet count (PC), mean corpuscular values (mean corpuscular Hgb [MCH], MCH concentration, and mean corpuscular volume [MCV]), blood potency of hydrogen (pH), and erythrocyte sedimentation rate (ESR) over a period of 14 days.

Results: Significant changes were observed in some of the studied parameters. Of the 14 days' study period, PCV, Hgb concentration, total WBC count, PC, and neutrophil count showed no significant (p≥0.05) difference until day 2 post-storage (PS), while RBC count, ESR, MCV, and lymphocyte count showed no significant (p≥0.05) variation up until day 3 PS. Blood pH showed no significant (p≥0.05) variation within 24-h PS but was significantly (p≤0.05) higher than obtained values on days 1, 3, 7, 10, and 14 PS.

Conclusion: Based on our finding, we could suggest that hematological laboratories and hemotherapists could use canine blood stored in a plastic vacutainer for 2-3 days.

Keywords: anemia, blood, citrate phosphate dextrose adenine-1, plastic vacutainer, transfusion.

Nanoparticles of zinc oxide defeat chlorpyrifos-induced immunotoxic effects and histopathological alterations

Research (Published online: 22-03-2019)

14. Nanoparticles of zinc oxide defeat chlorpyrifos-induced immunotoxic effects and histopathological alterations

Sara S. Essa, Eiman M. El-Saied, Osama S. El-Tawil, Inas M. Gamal and Sahar S. Abd El-Rahman

Veterinary World, 12(3): 440-448

ABSTRACT

Background and Aim: Chlorpyrifos (CPF) is a widely used organophosphate insecticide. Nanoparticles of zinc oxide (ZnO NPs) physically showed effective adsorbing property for some insecticides. The study was conducted to estimate the potential effect of ZnO NPs against CPF toxicity.

Materials and Methods: Four groups of male rats were used; control group and three groups received drinking water contained 75 mg/L CPF, combined 75 mg/L CPF and 200 mg/L ZnO NPs, and 200 mg/L ZnO NPs, respectively.

Results: CPF significantly decreased macrophage activity, serum lysozyme activity, and levels of interleukin-2 (IL-2) and IL-6; increased the percentage of DNA degeneration on comet assay of lymphocytes and significantly elevated hepatic and splenic malondialdehyde contents; and decreased their glutathione contents. The liver and spleen showed marked histological alterations after exposure to CPF with decreased expression of acetylcholinesterase. The coadministration of ZnO NPs ameliorated most of the undesirable effects of CPF, through elevation of macrophage and serum lysozyme activities, increased the levels of IL-2 and IL-6, corrected the oxidative stress markers, and alleviated most of the adverse effect exerted by CPF in liver and spleen tissues.

Conclusion: The addition of ZnO NPs to CPF-contaminated drinking water may be useful as a powerful antioxidant agent against toxic damage induced by CPF particularly in individuals who are on daily occupational exposure to low doses of CPF.

Keywords: acetylcholinesterase, chlorpyrifos, immune system, pathology, zinc oxide nanoparticles.

Characterization and comparison of strains of Pasteurella multocida associated with cases of progressive atrophic rhinitis and porcine pneumonia in Argentina

Research (Published online: 21-03-2019)

13. Characterization and comparison of strains of Pasteurella multocida associated with cases of progressive atrophic rhinitis and porcine pneumonia in Argentina

Fernando A. Bessone, Maria Laura Soriano Perez, Gustavo Zielinski, Marina Dibarbora, M. B. Conde, Javier Cappuccio and Fabrisio Alustiza

Veterinary World, 12(3): 434-439

ABSTRACT

Background: Pasteurella multocida (Pm) is the causative agent of progressive atrophic rhinitis (PAR) and pneumonic pasteurellosis (PN) in pigs. Pm is a member of the porcine respiratory complex responsible for important economic loss in the pig industry.

Aim: This study aimed to characterize the Pm strains recovered from clinical cases of PN and PAR and to elucidate the antibiotic susceptibility profiles of the strains.

Materials and Methods: Sixty strains were characterized molecularly by polymerase chain reaction to determine species-specific gene, capsular type (A or D), and toxin A production. The agar diffusion method was employed to evaluate antibiotic resistance profiles.

Results: We found that 65% of strains belonged to capsular type A or D, and 15% of those were positive to toxA gene. The antibiotic susceptibility profiles found were sensitive in decreasing order to: Enrofloxacin, ceftiofur (CTF), ampicillin, tilmicosin (TIL), florfenicol (FFN), spectinomycin (SPC), gentamicin, oxytetracycline (OTC), and trimethoprim-sulfamethoxazole (TMS). Strains were resistant in decreasing order to: Lincomycin (LIN), tylosin (TYL), erythromycin (ERY), TMS, SPC, OTC, FFN, TIL, and CTF.

Conclusion: The toxA gene was detected in many Pm isolates from pneumonic lungs. Capsule type A or D was the most frequently found among the collected isolates. LIN, TYL, and ERY are the drugs which showed higher percentages of resistant isolates.

Keywords: antibiotics susceptibility profiles, molecular characterization, Pasteurella multocida, pig.