Features of formation of Yersinia enterocolitica biofilms

Research (Published online: 25-01-2019)

20. Features of formation of Yersinia enterocolitica biofilms

E. Lenchenko, D. Lozovoy, A. Strizhakov, Yu Vatnikov, V. Byakhova, Eu Kulikov, N. Sturov, V. Kuznetsov, V. Avdotin and V. Grishin

Veterinary World, 12(1): 136-140

ABSTRACT

Aim: The work aimed to study the morphology of colonies and their comparison by features of the formation of Yersinia enterocolitica biofilms.

Materials and Methods: Bacteria were cultured on a Yersinia Selective Agar medium ("CIN-agar") at 28°C for 24 h. The microorganisms were grown in meat-peptone broth with 1.0% glucose to measure the absolute values of the optical density of the culture. The optical density of the liquid was determined in a microplate photometric analyzer Immunochem-2100 (HTI, USA) at a wavelength of 490 nm. For the study of biofilms, the specimens were fixed for 3-5 h in pairs of 25.0% solution of glutaraldehyde (according to DV), and pairs of a 1.0% aqueous solution of osmic acid (OSO4) were used for contrasting for 2-3 min. The specimens were examined with stereoscopic microscopy "BIOMED MS-1 Stereo" (Russia) and scanning electron microscope "TM 3030 plus" (Holland).

Results: With stereoscopic microscopy of the colonies of Y. enterocolitica, the S-forms had an elevated intensely colored center, radial striation along the periphery, smooth edges, d ≤ 1.0 mm. R-form colonies had a dark color and a dry surface, were tuberous and had a dense center with a peripheral ridge, rugged edges, d ≥ 1.5 mm. The optical density of the Y. enterocolitica S-form showed that this type of microorganism belongs to the moderate producers of biofilms since the optical density of the sample (density of the sample - Ds) exceeded the optical density of control (density of the control - Dc) by 3 times. In Y. enterocolitica R-form (D ≤ 0.197) weakly produced biofilms, the optical density of the sample exceeded the optical density of the control by <2 times.

Conclusion: The ability to form biofilms, the variability of phenotypic features, and the multiplicity of virulence factors of bacteria significantly reduce the effectiveness of diagnostic studies. The development of accelerated methods of detection and differentiation of the virulent properties of pathogenic bacteria will allow scientifically to substantiate and develop a set of measures aimed at preventing animal diseases and obtaining safe livestock products to prevent human diseases. Thus, we need to pay attention to which forms of colonies do Y. enterocolitica form on solid nutrient media: S- or R-forms. Through this study, we know that bacteria-forming S-shaped colonies are more capable of forming biofilms than R-forms. It means that they are more pathogenic and can cause persistent infections due to adhesion and biofilm formation.

Keywords: adhesion, biofilms, clusters, electron microscopy, heteromorphism, matrix, optical microscopy, stereoscopic microscopy, Yersinia.

Molecular evidence of Ehrlichia canis and Anaplasma platys and the association of infections with hematological responses in naturally infected dogs in Kalasin, Thailand

Research (Published online: 23-01-2019)

19. Molecular evidence of Ehrlichia canis and Anaplasma platys and the association of infections with hematological responses in naturally infected dogs in Kalasin, Thailand

Supawadee Piratae, Priyakorn Senawong, Pornchalerm Chalermchat, Warissara Harnarsa and Benjawan Sae-chue

Veterinary World, 12(1): 131-135

ABSTRACT

Background: Tick-borne bacteria, Anaplasma platys and Ehrlichia canis are well recognized as the etiology of anemia and thrombocytopenia in dogs. The clinical signs of anaplasmosis and ehrlichiosis range from asymptomatic to severe symptoms. There are insufficient studies about epidemiological surveys of these blood parasites, also the association of infections with the hematological study.

Aim: This study aimed to screen A. platys and E. canis in naturally infected dogs and the effects of the infection on the levels of packed cell volume (PCV) and platelet count.

Materials and Methods: A total of 68 blood samples were collected from free-roaming dogs at Nong Kung Sri district, Kalasin Province, Thailand, and examined for A. platys and E. canis infection by polymerase chain reaction (PCR) and measured PCV levels and platelet count.

Results: Using nested PCR, 42.65% of dogs were infected with one or two pathogens. The molecular detection of anaplasmosis and ehrlichiosis in this population was 29.4% (95% confidence interval [CI]: 18.98-41.71) and 25% (95% CI: 14.4-35.3), respectively. Coinfection occurred at 11.8% (95% CI: 5.22-21.87). Infection with E. canis and coinfection showed significant association with PCV levels (p<0.05) while A. platys infection showed no statistical relationship. Infection with A. platys, E. canis, and coinfection had a non-significant correlation with platelet count (p>0.05).

Conclusion: This study provides data of anaplasmosis and ehrlichiosis in free-roaming dogs which indicated that these zoonotic diseases are widespread and require for disease frequency determination, especially in Kalasin Province of Thailand where data of tick-borne infections in dogs have not been reported.

Keywords: packed cell volume, platelet count, Thailand, tick-borne pathogens.

Serological profiling of rabies antibodies by enzyme-linked immunosorbent assay and its comparative analysis with rapid fluorescent focus inhibition test in mouse model

Research (Published online: 23-01-2019)

18. Serological profiling of rabies antibodies by enzyme-linked immunosorbent assay and its comparative analysis with rapid fluorescent focus inhibition test in mouse model

Ashis Debnath, Dinesh C. Pathak, Narayan Ramamurthy, Gulam Mohd, A. B. Pandey, Vikramaditya Upmanyu, A. K. Tiwari, R. Saravanan, Madhan Mohan Chellappa and Sohini Dey

Veterinary World, 12(1): 126-130

ABSTRACT

Aim: In this study, we have used enzyme-linked immunosorbent assay (ELISA) as an alternative test to replace the cumbersome rapid fluorescent focus inhibition test (RFFIT) to ascertain the immune status of immunized mice against rabies virus.

Materials and Methods: Rabies is a devastating disease worldwide caused by rabies virus. Proper usage of pre- or post-exposure rabies vaccine can prevent the disease transmission. In this study, mice were immunized with Vero cell-adapted inactivated rabies vaccine. RFFIT was used as a test to determine the serum neutralizing titers in infected/vaccinated mice. Seroprofiling of mice sera was done in vitro by ELISA.

Results: Twenty-one days post-immunization, both ELISA and RFFIT assays indicated similar antibody levels in mice sera that were immunized with Vero cell-adapted inactivated rabies vaccine. Both the tests were correlated, and the linearity was verified by the regression line (R2=0.979).

Conclusion: In this study, we profiled the serological status of Vero cell-adapted inactivated rabies vaccine through ELISA in mice model that correlated well with the OIE gold standard test RFFIT.

Keywords: comparison, enzyme-linked immunosorbent assay, inactivated vaccine, rabies, rapid fluorescent focus inhibition test.

Bacterial isolation from internal organs of rats (Rattus rattus) captured in Baghdad city of Iraq

Research (Published online: 22-01-2019)

17. Bacterial isolation from internal organs of rats (Rattus rattus) captured in Baghdad city of Iraq

Nagham Mohammed Ayyal, Zainab Abdulzahra Abbas, Abdulkarim Jafar Karim, Zainab Majid Abbas, Karima Akool Al-Salihi, Jenan Mahmood Khalaf, Dunya Dhafir Mahmood, Eman Abdullah Mohammed, Rawaa Saladdin Jumaa and Dhuha Ismaeel Abdul-Majeed

Veterinary World, 12(1): 119-125

ABSTRACT

Aim: Rats are accused in disseminating many zoonotic diseases. This study aimed to isolate and identify bacteria from internal organs of rats captured in Baghdad City, Iraq.

Materials and Methods: A total of 120 black rats (R. rattus) were trapped from different areas in Baghdad city. Rats were kept in individual plastic cages for 3 h before euthanizing. Deep pharyngeal swab, intestinal content, urine, and pieces of the liver and spleen, lung, kidney, and brain were obtained aseptically. The specimens were inoculated into peptone water and incubated at 37°C for 24 h for enrichment. A loopful of each specimen was then subcultured onto MacConkey Agar, Blood Agar, and Mannitol Salt Agar. CHROMagar O157 H7 and CHROMagar Listeria were used to detect Escherichia coli 157:7 and Listeria spp., respectively. Biochemical tests on analytical profile index, microscopic examination, and commercial kit for latex agglutination test for serotyping E. coli O157:H7 were used.

Results: Mixed bacterial isolates were recorded as 116, 52, 36, 28, 18, 6, and 4 from intestinal contents, deep pharyngeal, liver and spleen, urine, lung, brain, and kidney, respectively. Microorganisms included E. coli, Staphylococcus aureus, Streptococcus spp., Bacillus spp., Pseudomonas aeruginosa, Citrobacter freundii, Proteus vulgaris, E. coli O157:H7, Enterobacter cloacae, Listeria spp., Klebsiella spp., Ochrobactrum anthropi, Aeromonasspp., Brucella spp., Pseudomonas fluorescens, Escherichia fergusonii, Micrococcus spp., Morganella spp., Proteus mirabilis, Pseudomonas luteola, and Streptobacillus spp. The highest bacterial prevalence (88; 73.33%) was recorded for E. coli, where 68 isolates were identified from the intestinal contents. Of these, four isolates were E. coli O157:H7.

Conclusion: Rats are important carriers and transmitters of a number of pathogens and can disseminate these microorganisms to humans and animals.

Keywords: bacteria, different organs, Escherichia coli O157:H7, Pseudomonas aeruginosa, rat, urine.

Awareness and antibody detection of Newcastle disease virus in a neglected society in Nigeria

Research (Published online: 21-01-2019)

16. Awareness and antibody detection of Newcastle disease virus in a neglected society in Nigeria

Oluwafemi Babatunde Daodu, Julius Olaniyi Aiyedun, Rafiu Adebisi Kadir, Hauwa Motunrayo Ambali, Oladapo Oyedeji Oludairo, Isaac Dayo Olorunshola, Oluwakemi Christiana Daodu and Saka Saheed Baba

Veterinary World, 12(1): 112-118

ABSTRACT

Aim: This study aimed to assess the level of awareness of rural poultry farmers on vaccination and to detect Newcastle disease virus (NDV) antibody in local birds (LB) and eggs in Kwara State, Nigeria.

Materials and Methods: Data on farmers' attitude, knowledge, practices, and experiences on ND mortality were obtained through an interview using a structured cross-sectional checklist. NDV antibodies were detected in sera and egg yolks of local chickens (LC) and guinea fowls (GF) using hemagglutination inhibition test.

Results: A total of 83 interviewees, 287 sera and 121 egg yolk extracts, were examined. The study revealed that 98.8% (82/83) of the interviewee had never vaccinated their flock before. 90% of the interviewee had reported high mortality in birds within 1-6 months old, while the major clinical signs were cold (40.4%) and torticollis (30.8%). Evidences of LB exposure to wild-type NDV were confirmed by the detection of NDV antibodies in 20.8% and 0% of LC and GF, respectively. The mortality differences experienced in <1 and 1-6 months old LB could be explained by the presence of maternally-derived NDV antibody (49.6%) in egg yolk.

Conclusion: The study showed that LB suffers from NDV as a result of LB keepers' ignorance and neglect by the government. This has limited local investment and subsequent contribution to gross domestic product. This study suggests that the key factors to the prevention of ND remain awareness creation about poultry vaccination, production of affordable vaccines, and availability/accessibility to veterinarian (or trained personnel).

Keywords: antibody detection, awareness, local birds, neglected communities, Newcastle disease, vaccination.

Hematologic changes and splenic index on malaria mice models given Syzygium cumini extract as an adjuvant therapy

Research (Published online: 21-01-2019)

15. Hematologic changes and splenic index on malaria mice models given Syzygium cumini extract as an adjuvant therapy

Lilik Maslachah, Rahmi Sugihartuti and Retno Sri Wahyuni

Veterinary World, 12(1): 106-111

ABSTRACT

Aim: This research aimed to determine the efficacy of Syzygium cumini L. as an adjuvant therapy on blood changes and splenic index of mice model malaria.

Materials and Methods: Mice were infected intraperitoneally with 0.2 ml red blood cell (RBC) that contains 1×106 Plasmodium berghei. 35 mice were divided into seven treatment groups: Group K0: Mice were not infected; K1: Mice were infected; K2: Mice were infected and given chloroquine; P1: Mice were infected and given S. cumini leaf extract; P2: Mice were infected and given chloroquine and also S. cumini leaf extract; P3: Mice was infected and given S. cumini stem bark extract; and P4: Mice were infected and given chloroquine and S. cumini stem bark extract. Treatment was given for 4 days 24 h post-P. berghei infection. 21st day post-P. berghei infection, blood was taken from the heart for hematological examination, and the spleen was taken to examine the splenic index and also to measure the weight and length of the spleen. Hematological data and splenic index were analyzed by analysis of variance test, and if there is a difference, the test is continued by Duncan's multiple range test with 5% level.

Results: The K0 group has normal hemoglobin (HGB), RBC, and hematocrit (HCT) and significantly different (p<0.05) than other groups. HGB, RBC, and HCT of K1 group were under normal range, lowest, and significantly different (p<0.05) than other groups. Mean corpuscular volume and mean corpuscular HGB values of K2 groups showed a decrease. The number of leukocytes, lymphocytes, and monocytes of K1 groups was increasing and significantly different (p<0.05) with K2 and treatment group. The length, width, weight, and splenic index of K1 group were significantly different (p<0.05) with K0 group. K2 and treatment groups showed that the length and width of spleens were significantly different (p<0.05) with K1.

Conclusion: The combination of chloroquine with leaf and chloroquine with stem bark extract of S. cumini as adjuvant therapy may increase the amount of erythrocyte; decrease the number of leukocytes, lymphocytes, and monocytes; and decrease the length, width, and splenic index on malaria mice models.

Keywords: hematology, splenic index, Syzygium cumini, Plasmodium berghei.

Combined H5ND inactivated vaccine protects chickens against challenge by different clades of highly pathogenic avian influenza viruses subtype H5 and virulent Newcastle disease virus

Research (Published online: 21-01-2019)

14. Combined H5ND inactivated vaccine protects chickens against challenge by different clades of highly pathogenic avian influenza viruses subtype H5 and virulent Newcastle disease virus

Ahmed Ali, Marwa Safwat, Walid H. Kilany, Abdou Nagy, Awad A. Shehata, Mohamed A. Zain El-Abideen, Al-Hussien M. Dahshan and Abdel-Satar A. Arafa

Veterinary World, 12(1): 97-105

Aim: The aim of the current study was to evaluate the efficacy of a trivalent-inactivated oil-emulsion vaccine against challenge by different clades highly pathogenic avian influenza (HPAI) viruses including HPAI-H5N8 and the virulent genotype VII Newcastle disease virus (NDV) (vNDV).

Materials and Methods: The vaccine studied herein is composed of reassortant AI viruses rgA/Chicken/Egypt/ ME1010/2016 (clade 2.2.1.1), H5N1 rgA/Chicken/Egypt/RG-173CAL/2017 (clade 2.2.1.2), and "NDV" (LaSota NDV/ CK/Egypt/11478AF/11); all used at a concentration of 108 EID50/bird and mixed with Montanide-ISA70 oil adjuvant. Two-week-old specific pathogen free (SPF) chickens were immunized subcutaneously with 0.5 ml of the vaccine, and hemagglutination inhibition (HI) antibody titers were monitored weekly. The intranasal challenge was conducted 4 weeks post-vaccination (PV) using 106 EID50/0.1 ml of the different virulent HPAI-H5N1 viruses representing clades 2.2.1, 2.2.1.1, 2.2.1.2, 2.3.4.4b-H5N8, and the vNDV.

Results: The vaccine induced HI antibody titers of >6log2 against both H5N1 and NDV viruses at 2 weeks PV. Clinical protection against all HPAI H5N1 viruses and vNDV was 100%, except for HPAI H5N1 clade-2.2.1 and HPAI H5N8 clade- 2.3.4.4b viruses that showed 93.3% protection. Challenged SPF chickens showed significant decreases in the virus shedding titers up to <3log10 compared to challenge control chickens. No virus shedding was detected 6 "days post-challenge" in all vaccinated challenged groups.

Conclusion: Our results indicate that the trivalent H5ND vaccine provides significant clinical protection against different clades of the HPAI viruses including the newly emerging H5N8 HPAI virus. Availability of such potent multivalent oil-emulsion vaccine offers an effective tool against HPAI control in endemic countries and promises simpler vaccination programs.

Keywords: avian influenza, Egypt, H5N1, H5N8, H5ND, Newcastle diseases virus, trivalent vaccine.