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New records of Rickettsia bellii-infected ticks in Brazil
2017
Francisco Borges Costa | Amália Regina Barbieri | Matias pablo Juan Szabó | Vanessa Nascimento Ramos | Ubiratan Piovezan | Marcelo Bahia Labruna
This study investigated the occurrence of rickettsial infection in ticks collected from wild animals in two areas of Brazil. Amblyomma dubitatum ticks were collected from a capybara (Hydrochoerus hydrochaeris) in Guarda-Mor municipality, state of Minas Gerais, and Amblyomma pseudoconcolor ticks were collected from a six-banded armadillo (Euphractus sexcinctus) in Corumbá municipality, state of Mato Grosso do Sul. Attempts to isolate rickettsia in Vero cell culture were performed with one A. dubitatum tick and one A. pseudoconcolor tick, which were previously shown by the hemolymph test to contain Rickettsia-like structures within their hemocytes. Rickettsiae were successfully isolated in Vero cell culture from the two tick species. The two isolates were identified as Rickettsia bellii, since gltA partial sequences were 99.9%-100% identical to corresponding sequences of R. bellii in GenBank. While there have been several previous reports of R. bellii infecting A. dubitatum ticks, we provide the first report for A. pseudoconcolor, which increases to 25 the number of R. bellii-infected tick species in the American continent.
اظهر المزيد [+] اقل [-]Isolation of Lumpy skin disease virus form naturally infected cattle previously vaccinated with live attenuated sheep poxvirus vaccine
2007
S. M. Tamam
Lumpy skin disease virus (LSDV) was isolated, from naturally infected cattle that have a history of previous vaccination with live attenuated sheep pox virus (SPV) vaccine. The virus was isolated on chorio-allantoic membrane (CAM) of specific pathogen free (SPF) embryonated chicken eggs (ECE) and identified by agar gel precipitation test (AGPT) and neutralization test using specific hyperimmune serum against LSDV and SPV. Characteristic intracytoplasmic inclusion bodies was detected in trypsenized cell of infected CAM stained with H&E. Laboratory studies for characterization of isolated LSDV revealed that it was stable at a wide range of pH, but it was inactivated by exposure to 56 0C for 15 minutes. Treatment of isolated LSDV with lipid solvents (20% ethyle ether and chloroform) reduced the virus titer 3.2 and 4.4 log respectively after 24 hrs at 4 0C .On cross neutralization testcomplete neutralization of isolated LSDV was obtained with both reference LSDV and SPV antisera. Cattle vaccinated with live attenuated SPV vaccine under experimental condition found to be protected against natural field infection with LSDV.
اظهر المزيد [+] اقل [-]Serological and molecular characterization of recent lumpy skin disease virus isolates from naturally infected previously vaccinated cattle in Egypt
2018
Tamam, S.M. | El-Shereif, N.M. | Shokier, K.A
lumpy skin disease virus (LSDV) was isolated, from naturally infected cattle that have a history of previous vaccination with live attenuated sheep pox virus (SPV) vaccine. The virus was isolated on chorio-allantoic membranes (CAM) of embryonated chicken eggs (ECE) and Madin Darby Bovine Kidney Cells (MDBK) and identified by agar gel precipitation test (AGPT) and immunofluorescent antibody technique (IFA). Characteristic pock lesions and intracyptoplasmic flourescene granules are identified respectively. Molecular characterization using polymerase chain reaction (PCR) using specific primer for G-Protein Coupled Chemokine Receptor Gene of LSDV isolates specific amplified product 554 bp. Sequence analysis revealed tow new isolates of LSDV.
اظهر المزيد [+] اقل [-]Bovine Parapoxvirus: Isolation and pathogenicity studies
2007
A. S. Abdel-Moneim | S. M. Tamam
A disease characterized by papules, nodules, vesicles, pustules and ulcers on teats and udder as well as drastic drop in milk production was seen among a cattle farm in Fayoum Governorate, Egypt. A virus was isolated by inoculation of vesicle and scrap homogenate pool from infected cattle into the chorioallantoic membrane of specific pathogen free embryonated chicken eggs. The virus was identified by presence of pock lesions, intracytoplasmic inclusion bodies on the chorioallantoic membrane, polymerase chain reaction and immunohistochemistry of the inoculated membrane. A novel pathogenicity model was developed via ear pinna inoculation of Swiss mice. The virus produced vesicular and ulcerative lesions at the site of inoculation in inoculated mice. The virus identity was confirmed by the presence of intracytoplasmic viral antigens by immunohistochemistry
اظهر المزيد [+] اقل [-]Isolation, molecular characterization and pathogenicity studies of infectious bursal disease field virus isolates
2018
M. M. Amer | K. M. El-Bayomi | M. Abd-A. Kotkat | Wafaa A. Abdel-Ghany | M. A. Shakal | Sherein S. Abdel-Gaied
This study was carried out to investigate the prevalence, molecular characterization and pathogenicity of field infectious bursal disease virus (IBDV) isolates. Nine isolates of IBDV were isolated from 13 naturally infected broiler flocks. Detection of IBDV antigen was carried out by agar gel precipitation test (AGPT), followed by virus isolation in specific pathogen free (SPF) embryonated chicken eggs (ECE) and finally molecularly characterized and identified using reverse transcriptase polymerase chain reaction (RT-PCR). The obtained nine strains of IBDV by RT-PCR were further classified by using restriction fragment length polymorphism (RFLP) technique into (4) classical, (3) variant and (2) very virulent (vv) IBDV serotype (I). The pathogenicity of the isolated IBDV strains was detected by three passages in SPF ECEs and by experimental infection of one hundred 14 days old maternally immune layer chicks. The results showed that the mortality rate of the embryos was increased by increase the number of passages till the third passage where it reached 100% for all IBDV strains and the embryos showed typical lesions of IBDV. Chicks inoculated with variant IBDV strains showed morbidity rates of 60-80 %, without mortalities. Sacrificed birds showed atrophied bursae and thymus glands and enlarged thickened proventriculus. Groups infected with classical IBDV strains showed morbidity rates 40- 60,% with mortality 0-20%. The detectable lesions were muscular hemorrhages with variable bursal lesions. Inoculated chicks with vvIBDV strains showed 50-70% morbidity and mortality of rate was 30% with lesions of muscular hemorrhages, severe nephrosis with ureates in the ureters, hemorrhagic bursitis and pin point hemorrhages on the proventricular glands. Control negative non-infected group showed neither clinical signs nor mortalities along the observation period. The histopathological effect (lesion score) of IBDV strains on the bursa, spleen and thymus glands confirmed the previously mentioned results and revealed that the highest severity (score) for these organs were induced by vv IBDV strains.
اظهر المزيد [+] اقل [-]Pasteurella organism: Its isolation and identification from pneumonic lungs of goats in Ethiopia
2017
Shimelis Mengistu Hailu | Dinaol Belina Kitila | Amare Eshetu Gemeda | Mitiku Tarekegn
Objective: The objective of this study was to isolate and identify Pasteurella spp. associated with pneumonic lungs showing respiratory signs of goats in Ethiopia.Materials and methods: A total of 2400 goats that were slaughtered at the Hashim’s Ethiopian Livestock and Meat Export abattoir, Ethiopia were randomly selected for this cross-sectional study during the period of October 2013 to July 2014. Detail ante-mortem, and post-mortem (PM) lesions were inspected, and the suspected samples were collected aseptically from the lungs. Among 2400 goats, 31(1.29%) goats were not slaughtered because these goats showed severe clinical signs. Thus, 2369 goats were slaughtered finally. The collected samples were subjected for isolation and identification of bacterial species following conventional methods such as culture and biochemical examinations. Results: Out of 2400 goats examined, 960(40%) animals showed different abnormal respiratory signs. Based on PM findings, 16.21% (n=384/2369) lungs were found as pneumonic, of which 78.38% (n=301/384) were found to be associated with Pasteurella organism. The overall prevalence of Pasteurella organism (Mannheimia haemolytica and Pasteurella multocida) was 12.71% (n=301/2369). In this study, youngers and goats with medium body condition score (BCS) had greater probability (P<0.05) to be infected by the bacteria though there was no difference in exposure to the organism among goats from Arsi, Bale and Hararghe. On the other hand, out of 301 positive cases, 274(91.03%) were caused by M. haemolytica, and 27(8.97%) were caused by P. multocida isolates. Conclusion: Pasteurella organism especially M. hemolytica is one of the most common causes of pneumonic pasteurellosis in caprine at the study area. So, chemoprophylaxis needs to be given to small ruminants prior to transportation or other stress conditions. [J Adv Vet Anim Res 2017; 4(2.000): 147-154]
اظهر المزيد [+] اقل [-]Salmonella infection in clinically healthy dogs in Makurdi, Benue State, North-central Nigeria: A potential source of infection to humans
2018
Chinedu Adive Akwuobu | Joseph Odeh Agbo | Raphael Agbo-Peters Ofukwu
Objective: The present study was initiated to ascertain the level of shedding of salmonellae by dogs in Makurdi area and to highlight the risk of infection for dog-owners.Materials and Methods: Rectal swabs from 200 dogs from different locations in the studyarea were examined in the study. The samples were cultured for salmonellae using Rappaport-Vassiliadis enrichment broth (Oxoid) and brilliant green agar (Oxoid). Suspected Salmonella isolates were serologically identified.Results: Overall, Salmonellae organisms were isolated from 11 (5.5%) of the 200 dogs sampled. Prevalence rates of 5.6% and 4.5% were recorded for apparently healthy and clinically sick dogs, respectively. Salmonella was respectively isolated from 4.1% to 9.1% of male and female dogs. Dogs aged 4 years and above recorded the highest prevalence rate. The study revealed a low prevalence rate in Nigerian local breed (mongrels) and high prevalence rates in exotic breeds of dogs.Conclusion: The isolation of salmonellae in apparently healthy and clinically sick dogs in this study indicates a carrier status which may constitute a serious problem in disease control in the study area. The lower prevalence rate of Salmonella infection in mongrels could be an indication of resistance to Salmonella in local breeds of dogs and should generate interest in research in the pathogenicity and pathogenesis of salmonellae in mongrels. [J Adv Vet Anim Res 2018; 5(4.000): 405-409]
اظهر المزيد [+] اقل [-]Isolation and antibiogram of Salmonella spp. from duck and pigeon in Dinajpur, Bangladesh
2016
Md. Moshiur Rahman | Md. Mostafizer Rahman | Mirza Mienur Meher | Md. Safikul Islam Khan | AKM Mostafa Anower
Objective: This research work was conducted for isolation of Salmonella spp. from duck and pigeon and assessment of antibiotic sensitivity patterns of the isolated Salmonella spp.Materials and methods: A total of 48 duck samples comprising of liver (n=16) spleen (n=16) and intestinal content (n=16) were collected from 16 ducks (8 sick and 8 dead). Similarly, 42 pigeon samples comprising of liver (n=14), spleen (n=14) and intestinal contents (n=14) were collected from 14 pigeons (7 sick and 7 dead). The samples were collected from the selected Duck and Pigeon farms at three Upazillas (sub-districts) in Dinajpur district, Bangladesh. The samples were subjected for isolation and identification of Salmonella spp. following standard bacteriological examinations such as cultural and morphological characteristics, biochemical properties and motility test. Commercially available antibiotic discs were used for the assesment of antibiotic resistant patterns by disc diffusion method.Results: Salmonella spp. could be isolated from 39.58% (n=19/48) duck and 28.57% (n=12/42) pigeon samples. The growth of colony with different characteristics in Brilliant Green agar, Nutrient agar, Salmonella-Shigella agar and Mac Conkey agar indicated positive results. Dextrose and mannitol were fermented and in Triple Sugar Iron (TSI) slant media, the isolates produced red color, yellow in butt with slightly black color. Positive result was found in Indole and Methyl Red media. The isolated Salmonella organisms were found to be highly sensitive to Azithromycin, Ciprofloxacin and Levofloxacin. Conclusion: Pigeons and ducks found in the study area may be the carrier of Salmonella spp. The farm should be checked periodically to know the status of Salmonella infection. Further study might be isolation and identification of Salmonella organism with detail genomic analysis and drug resistance. [J Adv Vet Anim Res 2016; 3(4.000): 386-391]
اظهر المزيد [+] اقل [-]Molecular characterization of Duck Plague virus isolated from Bangladesh
2015
Md. Mostakin Ahamed | Muhammad Tofazzal Hossain | Marzia Rahman | K. H. M. Nazmul Hussain Nazir | Mohammad Ferdousur Rahman Khan | Md. Shafiullah Parvej | Wahedul Karim Ansari | Meher Negar Noor-A-Alahi Chiste | Khaled Bin Amin | Md. Liakot Hossen | Sultan Ahmed | M. Bahanur Rahman
Duck plague (DP) is the most feared duck disease in the world. For isolation, identification, molecular detection and characterization of DP virus (DPV), a total of 94 samples were collected from commercial farms (n=6) and households (n=13) from Rajshahi (n=37), Netrokona (n=35) and Mymensingh (n=22) districts of Bangladesh. The samples were processed and inoculated into 11-13 days old embryonated duck eggs for virus propagation. Virus was identified using agar gel immunodiffusion test (AGIT) and passive hemagglutination (PHA) test, and was confirmed by polymerase chain reaction (PCR) targeting DNA polymerase and gC genes, followed by sequencing. Pathogenicity tests were performed using duck embryos, ducklings and ducks. Among the 94 samples, 17 isolates were confirmed as DPV by PCR amplification of partial DNA polymerase (446-bp) and gC genes (78-bp), respectively. One of the isolates (Anatid herpes 1 BAU DMH) was sequenced and found to be closely related with a Chinese variant of DPV (GenBank: JQ647509.1). Thus, we assume that both Bangladeshi and Chinese isolates of DPV may have a common ancestor. [J Adv Vet Anim Res 2015; 2(3.000): 296-303]
اظهر المزيد [+] اقل [-]Isolation and genetic diversity of fowlpox virus circulating in chicken flocks in Egypt
2024
Neven M. Ramzy | Ayatollah I. Ibrahim | Mohamed S. Abd el hafez | Eman A. Shosha
FowlPox virus (FPV) was detected in eight chickens suffering from a diphtheritic lesion on the oropharynx and trachea with nodular skin lesions around the unfeathered parts in two Egyptian governorates (El-Sharkia and Ismailia governorates) during summer 2023. A variety of serological and molecular methods were performed for identification and characterization of the virus. on specific-pathogen free (SPF) embryonated chicken eggs via chorio-allantoic membranes (CAM), the distinguishing focal pock lesions were detected on CAM. Concerning electron microscopy, FPV appeared as enveloped quadrangular brick shaped Avipoxvirions. The neutralizing antibodies level against FPV were detected in all eight samples. Serum neutralization test showed a neutralization index of ≥ 1.6 in all serum samples, meanwhile ELISA test displayed an S/P ratio of ≥ 1.5 in the affected chickens. Notably, two positive FPV samples were sequenced then submitted to the GenBank (Sharquia-1 and Ismilia-2 with accession numbers; OR920788-OR920789). The phylogenetic tree construction based on the fpv167- (P4b) gene of FPV revealed high nucleotide identity with Elsharqyia_FWPV1, Elsharqyia_FWPV2 and Fowlpox-AN5, FWPVN, FWPVD (Egyptian isolates) with nucleotide identity percentage 100%, 99%, 100%, 99%,99%; respectively. Likewise, FPV isolates were of low homology with VSVRI-Vac (vaccinal strain) with 88% similarity. In context, the local recent our strains can be applied in vaccine production for appropriate vaccination programs in Egypt.
اظهر المزيد [+] اقل [-]