Combined impacts of oregano extract and vacuum packaging on the quality changes of frigate tuna muscles stored at 3±1°C

Research (Published online: 28-01-2019)

23. Combined impacts of oregano extract and vacuum packaging on the quality changes of frigate tuna muscles stored at 3±1°C

Talal Lahreche, Yilmaz Ucar, Ali Riza Kosker, Taha-Mossadak Hamdi and Fatih Ozogul

Veterinary World, 12(1): 155-164

ABSTRACT

Aim: The combined effects of oregano extract with vacuum packing (VP) on the quality enhancement of dark and white muscles of frigate tuna (Auxis thazard) stored as intact fillet at refrigerated (3±1°C) conditions were studied.

Materials and Methods: About 35 kg of fish were filleted without skin removal and randomly divided into two groups. One group without treatment (control) and the remaining group were dipped in a sterilized oregano extract solution for 5 min. Chemical, microbiological, sensorial, and textural analyses were carried out in each of dark and white muscles of frigate tuna fillets during storage.

Results: Several quality indexes were higher in dark muscle than white muscle. The sensory assessment indicated that both muscles from control had a shelf life of 12 days. Quality parameters of both muscles had the same tendency and were significantly affected by time and also by the presence of plant extract in VP. Although VP alone was sufficient to delay lipid oxidation on fish fillets, especially on dark muscle but cannot enhance the textural deterioration in both muscles.

Conclusion: Consequently, the employment of such combination had a cumulative effect on preservation, resulting in prolonging the shelf life of both frigate tuna muscles.

Keywords: dipping, fish muscles, oregano extract, quality parameters, refrigerated storage, vacuum packaging.

Random amplified polymorphic DNA-based molecular heterogeneity analysis of Salmonella entericaisolates from foods of animal origin

Research (Published online: 26-01-2019)

22. Random amplified polymorphic DNA-based molecular heterogeneity analysis of Salmonella entericaisolates from foods of animal origin

Surendra Singh Shekhawat, Abhishek Gaurav, Bincy Joseph, Hitesh Kumar and Nirmal Kumar

Veterinary World, 12(1): 146-154

ABSTRACT

Aim: This study aims to study the significance of random amplified polymorphic DNA (RAPD) typing in heterogeneity analysis of Salmonella serovars, isolated from foods of animal origin.

Materials and Methods: Salmonella serovars isolated and identified from different foods of animal origin such as meat, milk, and egg by standard bacteriological methods. DNA isolated from all 10 isolates which are confirmed by biochemical and serotyping methods and then RAPD was performed using the primers OPB 10, primer 1290, NSC I, NSC II, and primer 3. Then, RAPD data were analyzed using the BioNumerics software, Belgium, Germany.

Results: RAPD polymerase chain reaction (PCR) using five primers, namely OPB 10, primer 1290, NSC I, NSC II, and primer 3, classified the 10 isolates into 9, 10, 10, 7, and 10 RAPD-PCR types with discriminating powers of 0.1987, 0.423, 0.50889, 0.1842, and 0.2582, respectively. The phylogram constructed with NSC I profile classified isolates based on geographical origin. Primer 1290, NSC II, and primer 3 produced some uniform bands in all isolates indicating their binding ability in conserved genomic region. This study revealed that RAPD profile can be best used for finding out the heterogeneity at molecular level of Salmonella isolates in combination with other molecular and phenotypic typing techniques. Thus, our results support earlier observation of its significance by different workers on different Salmonella serotypes.

Conclusion: Repeatability of RAPD-PCR is insufficient to distinguish genetic differences among Salmonella serovars.

Keywords: Salmonella, random amplified polymorphic DNA, foods of animal origin, phylogram.

The occurrence of disinfectant and antibiotic-resistant genes in Escherichia coli isolated from chickens in Egypt

Research (Published online: 25-01-2019)

21. The occurrence of disinfectant and antibiotic-resistant genes in Escherichia coli isolated from chickens in Egypt

Waleed A. Ibrahim, Sherif A. Marouf, Ahmed M. Erfan, Soad A. Nasef and Jakeen K. El Jakee

Veterinary World, 12(1): 141-145

ABSTRACT

Aim: This work aimed to determine the occurrence of antibiotic and disinfectant resistance genes in Escherichia coli isolated from chickens in Egypt.

Materials and Methods: Organs (liver, lung, heart, yolk sac, and bone marrow) of 1500 chicken samples were collected from diseased chickens suffered from colibacillosis with PM findings as CRD, diarrhea and omphalitis from different governorates of Egypt as: Giza, EL-Bahira, Fayoum, El-Dakahlia, El-Ismalia, and El-Sharkia during 2015-2016. These samples were labeled and transported immediately on ice to the Reference laboratory for quality control on poultry production (RLQP). The samples were cultured onto MacConkey agar and Eosin Methylene Blue Agar. Isolation and identification of the E. coli were performed based on morphology, cultural, staining, and biochemical properties. Antimicrobial resistance test was carried out using disk diffusion method. The PCR employing tetA, qacED1 and qacA/B were carried out for detection of these genes in isolated E.coli.

Results: The prevalence of E. coli in chicken was 34%. Predominant serotypes of E. coli which serologically identified were O128, O111, O44, O158, and O2. Antibiotic susceptibility test of E. coli revealed that 100% of isolates were resistant to ampicillin, erythromycin, and sulfamethoxazole-trimethoprim, while 73.53% and 38.23% of them were sensitive for colistin sulfate and levofloxacin, respectively. Antibiotic resistance genes as tetA gene were tested for isolated E. coli and detected by incidence rate of 91.18%. qac resistance genes resembling as qacED1 and qacA/B genes were detected in isolated E. coli 70.6% and 14.7%, respectively.

Conclusion: E. coli isolated from chickens in Egypt was carried qac and antibiotic-resistant genes that affect the poultry industry.

Keywords: antimicrobial resistance, chickens, Egypt, Escherichia coli, qac resistance genes.

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.