Characterization and zoonotic impact of Shiga toxin producing Escherichia coli in some wild bird species

Research (Published online: 24-09-2017)

17. Characterization and zoonotic impact of Shiga toxin producing Escherichia coli in some wild bird species

Hanaa Mohamed Fadel, Rabab Afifi and Dheyazan Mohammed Al-Qabili

Veterinary World, 10(9): 1118-1128

ABSTRACT

Aim: Wild birds are considered silent vectors of some zoonotic water and food borne pathogens of public health significance. Owing to the importance of Shiga toxin producing Escherichia coli (STEC) as the most pathogenic among the emerging diarrheagenic E. coli groups that can infect man; the present study was designed to detect the occurrence of STEC among wild birds in Egypt.

Materials and Methods: A total of 177 intestinal content swab samples originating from five wild bird species were investigated for the presence of E. coli and STEC by standard culture methods. Suspect STEC isolates were further characterized by serotyping, random amplified polymorphic DNA polymerase chain reaction (RAPD PCR), antimicrobial resistance pattern and PCR detection of stx1, stx2, and eae genes.

Results: A total of 30 suspect STEC isolates from 30 positive birds' samples were detected and identified on STEC CHROMagar (semi-captive pigeons, 15; house crows, 8; cattle egrets, 3; moorhens, 2; and house teals, 2). 25 isolates were grouped into 13 serogroups (O:20, O:25, O:26, O:27, O:63, O:78, O:111, O:114, O:125, O:128, O:142, O:153, and O:158), while five were rough strains. The distribution of STEC virulence genes among wild birds was as follows: 16 birds carried stx1 gene only (nine pigeons [28.1%], six crows [7.1%], and one cattle egret [5.6%]). stx1 and stx2 genes together were detected in four birds (one cattle egret [5.6%], two moorhens [6.1%], and one house teal, [10%]). Only one pigeon (3.1%) possessed the three alleles. Disk diffusion test results showed that cefixime was the most effective against STEC serotypes with (93.3%) sensitivity, followed by gentamycin (56.7%), and amoxicillin (50%). On the other hand, all the recovered STEC isolates were resistant to cefotaxime, doxycycline, cephalothin, and sulfisoxazole. RAPD fingerprinting using primers OPA-2 and OPA-9 showed that STEC isolates were heterogeneous; they yielded 30 and 27 different clusters, respectively.

Conclusion: Wild birds carry STEC and may add to the contamination of the surrounding environment.

Keywords: antibiotic, eae, random-amplified polymorphic DNA polymerase chain reaction, Shiga toxin producing Escherichia coli, stx1, stx2, wild birds.

The effect of eggshell thickness on hatchability of quail eggs

Research (Published online: 23-09-2017)

16. The effect of eggshell thickness on hatchability of quail eggs

Oguz Fatih Ergun and Umut Sami Yamak

Veterinary World, 10(9): 1114-1117

ABSTRACT

Background and Aim: The aim of the successful incubation period is to achieve maximum health chicks in each batch. Therefore, all factors affecting incubation have to be investigated in detail. This study investigated the effect of eggshell thickness on hatchability of quail eggs.

Materials and Methods: A total of 1415 eggs were collected from the same flock at the ages of 23 and 41 weeks. Two different incubations were performed at these eggs. Eggshell thicknesses of all eggs were determined with an ultrasonic gauge before incubation. Incubation period was applied as for 18 days. After 15 days of incubation, eggs were transferred to hatching machine. Eggs were classified as thin-, medium-, and thick-shelled according to eggshell thickness values.

Results: Eggshell thicknesses were ranged between 0.24 and 0.36 mm, and the differences between the hatching rates of thickness values were not found significant. Hatchability of thin-, medium-, and thick-shelled eggs was found as 69.2%, 69.4%, and 82.4% for Experiment 1. These values were as 87.8%, 89.2%, and 91.9% for Experiment 2, respectively. Similar to eggshell thickness frequencies, the differences between hatching rates of eggshell thickness groups were found insignificant.

Conclusion: Results of this study showed that eggshell thickness does not affect hatchability.

Keywords: eggshell thickness, hatchability, incubation, quail, ultrasound.

Aboveground burial for managing catastrophic losses of livestock

Research (Published online: 22-09-2017)

9. Aboveground burial for managing catastrophic losses of livestock - Gary Alan Flory, Robert W. Peer, Robert A. Clark, Mohamed Naceur Baccar, Thanh-Thao Le, Aziz Ben Mbarek and Sami Farsi

International Journal of One Health, 3: 50-56

  doi: 10.14202/IJOH.2017.50-56

Abstract

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Background and Aim: Environmental impacts from carcass management are a significant concern globally. Despite a history of costly, ineffective, and environmentally damaging carcass disposal efforts, large animal carcass disposal methods have advanced little in the past decade. An outbreak today will likely be managed with the same carcass disposal techniques used in the previous decades and will likely result in the same economic, health, and environmental impacts. This article overviews the results of one field test that was completed in Virginia (United States) using the aboveground burial (AGB) technique and the disposal of 111 foot-and-mouth disease (FMD) infected sheep in Tunisia using a similar methodology.

Materials and Methods: Researchers in the United States conducted a field test to assess the environmental impact and effectiveness of AGB in decomposing livestock carcasses. The system design included a shallow trench excavated into native soil and a carbonaceous base placed on the bottom of the trenches followed by a single layer of animal carcasses. Excavated soils were subsequently placed on top of the animals, and a vegetative layer was established. A similar methodology was used in Tunisia to manage sheep infected with FMDs, Peste des Petits Ruminants virus, and Bluetongue Virus.

Results: The results of the field test in the United States demonstrated a significant carcass degradation during the 1-year period of the project, and the migration of nutrients below the carcasses appears to be limited thereby minimizing the threat of groundwater contamination. The methodology proved practical for the disposal of infected sheep carcasses in Tunisia.

Conclusions: Based on the analysis conducted to date, AGB appears to offer many benefits over traditional burial for catastrophic mortality management. Ongoing research will help to identify limitations of the method and determine where its application during large disease outbreaks or natural disasters is appropriate.

Keywords: aboveground burial, carcass disposal, foot-and-mouth disease, foreign animal diseases, mesophilic static pile composting.

Cloning and expression of P67 protein of Mycoplasma leachii

Research (Published online: 21-09-2017)

15. Cloning and expression of P67 protein of Mycoplasma leachii

Sabarinath Thankappan, Rajneesh Rana, Arun Thachappully Remesh, Valsala Rekha, Viswas Konasagara Nagaleekar and Bhavani Puvvala

Veterinary World, 10(9): 1108-1113

ABSTRACT

Aim: The present study was undertaken to clone, express and study the immunogenicity of P67 protein of Mycoplasma leachii.

Materials and Methods: P67 gene was amplified from genomic DNA of M. leachii. The polymerase chain reaction (PCR) product was inserted in pRham N-His SUMO Kan vector and was used to transform competent Escherichia cloni 10G cells. Recombinant protein expression was done by inducing cells with 0.2% Rhamnose. Purification was done using nickel nitrilotriacetic acid affinity chromatography. Western blot and dot blot analysis were performed to assess the immunoreactivity of P67 protein.

Results: PCR amplicon size of P67 gene was found to be 1500 base pair. The size of the fusion protein with SUMO tag was 79 kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. The recombinant P67 fusion protein expressed in pRham N-His SUMO Kan vector was found to be immunogenic in both western blot and dot blot analysis.

Conclusion: Western blot and dot blot analysis of P67 protein of M. leachii revealed that the protein is immunogenic. Further work is needed to evaluate the role of P67 antigen of M. leachii as an immunodiagnostic agent.

Keywords: cloning, dot blot, expression, Mycoplasma leachii, P67 protein, western blot.

Cloning and sequence analysis of hyaluronoglucosaminidase (nagH) gene of Clostridium chauvoei

Research (Published online: 21-09-2017)

14. Cloning and sequence analysis of hyaluronoglucosaminidase (nagH) gene of Clostridium chauvoei

Saroj K. Dangi, Pavan Kumar Yadav, Aakanksha Tiwari and Viswas Konasagara Nagaleekar

Veterinary World, 10(9): 1104-1107

ABSTRACT

Aim: Blackleg disease is caused by Clostridium chauvoei in ruminants. Although virulence factors such as C. chauvoei toxin A, sialidase, and flagellin are well characterized, hyaluronidases of C. chauvoei are not characterized. The present study was aimed at cloning and sequence analysis of hyaluronoglucosaminidase (nagH) gene of C. chauvoei.

Materials and Methods: C. chauvoei strain ATCC 10092 was grown in ATCC 2107 media and confirmed by polymerase chain reaction (PCR) using the primers specific for 16-23S rDNA spacer region. nagH gene of C. chauvoei was amplified and cloned into pRham-SUMO vector and transformed into Escherichia cloni 10G cells. The construct was then transformed into E. cloni cells. Colony PCR was carried out to screen the colonies followed by sequencing of nagH gene in the construct.

Results: PCR amplification yielded nagH gene of 1143 bp product, which was cloned in prokaryotic expression system. Colony PCR, as well as sequencing of nagH gene, confirmed the presence of insert. Sequence was then subjected to BLAST analysis of NCBI, which confirmed that the sequence was indeed of nagH gene of C. chauvoei. Phylogenetic analysis of the sequence showed that it is closely related to Clostridium perfringensand Clostridium paraputrificum.

Conclusion: The gene for virulence factor nagH was cloned into a prokaryotic expression vector and confirmed by sequencing.

Keywords: black quarter, Clostridium chauvoei, hyaluronoglucosaminidase.

Immunological and histopathological changes in sheep affected with cutaneous squamous cell carcinoma and treated immunotherapeutically

Research (Published online: 20-09-2017)

13. Immunological and histopathological changes in sheep affected with cutaneous squamous cell carcinoma and treated immunotherapeutically

Faten A. M. Abo-Aziza, A. A. Zaki, A. El-Shemy, Sahar S. Abd Elhalem and Amany S. Amer

Veterinary World, 10(9): 1094-1103

ABSTRACT

Background and Aim: Recently, it has been recorded unexpected percentage of cutaneous squamous cell carcinoma (cSCC) in sheep. Despite the improvement in surgical treatment, the outcome of animals remains limited by metastatic relapse. Although antibodies for cancer treatment have been practiced for many decades, the use of this methodology in animals is deficient. This study aimed to establish cSCC therapy by tumor cell protein antibody (Ab1) or secondary antibody (Ab2) raised by two series of immunization in the same strain of rabbits.

Materials and Methods: A total of 19 Ossimi sheep were used (14 sheep suffered from cSCC and 5 were apparently healthy). Each animal from control healthy group (n=5) and control cSCC (n=4) group was treated with a course of eight injections of normal globulins. Animals in the third (n=5) and the last (n=5) groups received a course of eight injections of Ab1and Ab2, respectively. Each tumor was measured before and after treatment. The eight injections were applied at 1st, 3rd, 5th, 7th, and 9th week and the remaining three injections were at 1 week interval. Tissue specimens and blood samples were taken for histological and immunological studies.

Results: The obtained results revealed that injection of Ab1 might prevent the bad prognostic picture of polymorph infiltration without any criteria of regression % of tumor. Treatment with Ab2 showed regression of tumor size ranged between minimum of 8.99% and maximum of 78.12%, however, the measurements in most cases reached the maximum regression after the past two injections. In additions, infiltration of lymphocytes to tumor site, normalization of leukocytes picture and also increase of antibody titer were observed.

Conclusion: This profile might confirm that Ab2 could act as an antigen and encourage us to use it as a tumor vaccine. Extensive studies are needed to isolate the idiotypic portion of Ab1 for raising Ab2 as an anti-idiotypic antibody to be used as tumor vaccine. The question of how lymphocyte traffic to the tumor site as a result of Ab2 injection needs further investigation.

Keywords: antibody, cutaneous squamous cell carcinoma, histopathology, immunotherapy, sheep.

Matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry as a reliable proteomic method for characterization of Escherichia coli and Salmonella isolates

Research (Published online: 19-09-2017)

12. Matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry as a reliable proteomic method for characterization of Escherichia coli and Salmonella isolates

Waleed S. Shell, Mahmoud Lotfy Sayed, Fatma Mohamed Gad Allah, Fatma Elzahraa Mohamed Gamal, Afaf Ahmed Khder, A. A. Samy and Abde Hakam M. Ali

Veterinary World, 10(9): 1083-1093

ABSTRACT

Aim: Identification of pathogenic clinical bacterial isolates is mainly dependent on phenotypic and genotypic characteristics of the microorganisms. These conventional methods are costive, time-consuming, and need special skills and training. An alternative, mass spectral (proteomics) analysis method for identification of clinical bacterial isolates has been recognized as a rapid, reliable, and economical method for identification. This study was aimed to evaluate and compare the performance, sensitivity and reliability of traditional bacteriology, phenotypic methods and matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry (MALDI-TOF MS) in the identification of clinical Escherichia coli and Salmonella isolates recovered from chickens.

Materials and Methods: A total of 110 samples (cloacal, liver, spleen, and/or gall bladder) were collected from apparently healthy and diseased chickens showing clinical signs as white chalky diarrhea, pasty vent, and decrease egg production as well as freshly dead chickens which showing postmortem lesions as enlarged liver with congestion and enlarged gall bladder from different poultry farms.

Results: Depending on colonial characteristics and morphological characteristics, E. coli and Salmonella isolates were recovered and detected in only 42 and 35 samples, respectively. Biochemical identification using API 20E identification system revealed that the suspected E. coli isolates were 33 out of 42 of colonial and morphological identified E. coli isolates where Salmonella isolates were represented by 26 out of 35 of colonial and morphological identified Salmonella isolates. Serological identification of isolates revealed that the most predominant E. coli serotypes were O1 and O78 while the most predominant Salmonella serotype of Salmonellawas Salmonella Pullorum. All E. coli and Salmonella isolates were examined using MALDI-TOF MS. In agreement with traditional identification, MADI-TOF MS identified all clinical bacterial samples with valid scores as E. coli and Salmonella isolates except two E. coli isolates recovered from apparently healthy and diseased birds, respectively, with recovery rate of 93.9% and 2 Salmonella isolates recovered from apparently healthy and dead birds, respectively, with recovery rate of 92.3%.

Conclusion: Our study demonstrated that Bruker MALDI-TOF MS Biotyper is a reliable rapid and economic tool for the identification of Gram-negative bacteria especially E. coli and Salmonella which could be used as an alternative diagnostic tool for routine identification and differentiation of clinical isolates in the bacteriological laboratory. MALDI-TOF MS need more validation and verification and more study on the performance of direct colony and extraction methods to detect the most sensitive one and also need using more samples to detect sensitivity, reliability, and performance of this type of bacterial identification.

Keywords: ABI, Bruker Daltonics, colibacillosis, Escherichia coli, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, Salmonella, Salmonella pullorum.