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result(s) for
"Tolba, Hala"
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Molecular identification and antiprotozoal activity of silver nanoparticles on viability of Cryptosporidium parvum isolated from pigeons, pigeon fanciers and water
by
Attia, Amira S. A.
,
Abou Elez, Rasha M. M.
,
Elsohaby, Ibrahim
in
692/308/174
,
692/499
,
692/699/255/1715
2023
Cryptosporidium
is a protozoan that causes acute gastroenteritis, abdominal pain, and diarrhea in many vertebrate species, including humans, animals and birds. A number of studies have reported the occurrence of
Cryptosporidium
in domestic pigeons. Thus, this study aimed to identify
Cryptosporidium
spp. in samples collected from domestic pigeons, pigeon fanciers, and drinking water, as well as to investigate the antiprotozoal activity of biosynthesized silver nanoparticles (AgNPs) on the viability of isolated
Cryptosporidium parvum
(
C. parvum
). Samples were collected from domestic pigeons (n = 150), pigeon fanciers (n = 50), and drinking water (n = 50) and examined for the presence of
Cryptosporidium
spp. using microscopic and molecular techniques. The antiprotozoal activity of AgNPs was then assessed both in vitro and in vivo.
Cryptosporidium
spp. was identified in 16.4% of all examined samples, with
C. parvum
identified in 5.6%. The highest frequency of isolation was from domestic pigeon, rather than from pigeon fanciers or drinking water. In domestic pigeons, there was a significant association between
Cryptosporidium
spp. positivity and pigeon's age, droppings consistency, housing, hygienic and heath conditions. However,
Cryptosporidium
spp. positivity was only significantly associated with pigeon fanciers' gender and heath condition. The viability of
C. parvum
oocysts was reduced using AgNPs at various concentrations and storage times in a descending manner. In an in vitro study, the highest reduction in
C. parvum
count was observed at the AgNPs concentration of 1000 µg/mL after a 24 h contact time, followed by the AgNPs concentration of 500 µg/mL after a 24 h contact time. However, after a 48 h contact time, a complete reduction was observed at both 1000 and 500 µg/mL concentrations. Overall, the count and viability of
C. parvum
decreased with increasing the AgNPs concentration and contact times in both the in vitro and in vivo studies. Furthermore, the
C. parvum
oocyst destruction was time-dependent and increased with increasing the contact time at various AgNPs concentrations.
Journal Article
Evaluation and development of diagnostic tools for rapid detection of Riemerella anatipestifer and Pasteurella multocida in ducks
2023
Objectives: Ducks suffer a huge economic loss as a result of infections with Pasteurella multocida and Riemerella anatipestifer, which cause high morbidity and mortality. Because these patho¬gens induce similar clinical symptoms when coinfections occur, it is very difficult to differentiate between them based just on clinical signs. Hence, these major pathogens must be quickly and accurately detected.
Materials and Methods: A total of 104 birds ranging from 2 days to 4 weeks old were collected from Egyptian farms, and the outcomes were compared statistically. Conventional cultural iden¬tification procedures and a direct multiplex polymerase chain reaction assay were utilized to recognize both pathogens in a single tube reaction simultaneously. Then, the obtained isolates were characterized phenotypically and genotypically.
Results: Clinical signs appear at 2–4 weeks of age with respiratory distress (dyspnea), white fluid feces, and stunting. The scrutinized data demonstrated a significantly higher detection rate by PCR directly compared to classical culture procedures. Pasteurella multocida was detected only by PCR. The disc diffusion technique against ten antibiotics showed absolute susceptibilities to amik¬acin, doxycycline, and florfenicol. High levels of beta-lactam resistance were observed. Riemerella anatipestifer isolates were screened for pathogenicity and plasmid-borne blaTEM genes. All six isolates harbored five virulence genes: aspC, RA46, m28, pstS, and Nlp/P60. Moreover, blaTEM was identified into four isolates and deposited to GenBank with accession numbers OP347083, OP347084, OP347085, and OP347086.
Conclusion: These results suggest advanced PCR assays can be applied to the field for rapid and valuable diagnosis of two significant pathogens and focus on the worth of ducks in the propaga¬tion of transferable antibiotic resistance genes into the environment.
Journal Article
Effect of Forage Moringa oleifera L. (moringa) on Animal Health and Nutrition and Its Beneficial Applications in Soil, Plants and Water Purification
by
Desoky, El-Sayed M.
,
Elnesr, Shaaban S.
,
Elnahal, Ahmed S. M.
in
Agricultural practices
,
Amino acids
,
animal
2018
Moringa oleifera L. (moringa) is known as one of the most useful multipurpose plants. It can be effectively utilized as a natural biopesticide and inhibitor of several plant pathogens. Thus, it can be included in integrated pest management strategies. Moringa and its products have different uses in many agricultural systems. The use of moringa as a crop enhancer is an eco-friendly way of improving crop yields at the lowest possible cost. This inexpensive increase in productivity can contribute to meeting some of the food needs in some parts of the world as the global population increases and poverty rates rise. One of the most important characteristics of moringa is that it has high biological and nutritional values and can be used as animal feed, green fertilizer, medicine, biopesticide and in seed production. Moringa has been characterized as a potentially useful animal feed owing to its high content of protein, carotenoids, several minerals and vitamins (such as iron and ascorbic acid) and certain phytochemicals (kaempferitrin, isoquercitrin, rhamnetin, kaempferol and quercetin). This review aims to provide more knowledge about the nature, nutritional value, phytochemicals and uses of Moringa oleifera as a promising material in the fields of soil and plant management, water treatment, as well as animal and poultry production.
Journal Article
H5N1 Avian Flu Infection in Hubbard Broiler Chicken Can Be Prevented or Cured by Methylated Soy Protein During 42 Days Rearing
2022
Methylated soy protein (MSP) which is positively charged with enhanced hydrophobicity may have antiviral action. This study is verifying if MSP can act inhibit H5N1 inside an animal model. Five groups of Hubbard chicks were challenged at the 25th day of the experiment with AIV virus (H5N1; 0.1 × 10
5
EID
50
/mL); 1 group did not receive any treatment (positive control), 2 groups (protective) received treatments before and after the challenge (0.1–0.2 g/L in drinking water ad libitum), and 2 groups (curative) received them only after the challenge. The positive control recorded 100% mortality after 3–5 days of infection. Chicken receiving MSP (0.2 g/L), delayed reaching to 100% mortality to the 7
th
day after infection, while those receiving MSP low level (0.1 g/L) could achieve 100% survival during the whole incubation period (42 days), either as a preventive or curative approach. H5N1 virus was not detected in the tracheal and cloacal swabs of the groups receiving 0.1 g/L, opposite to the positive control. The low level of MSP (0.1 g/L) reduced the viral titer to about 1% of the positive control in the protective and curative groups after 5 days of infection, and could maintain the bird body-weight, liver and kidney function, and histopathological status within the normal values. Humoral and TLC response in the group receiving both the virus and the MSP (0.1 g/L) may refer to a possibility that MSP-weakened virus has transformed into a vaccine-like material eliciting host immunity.
Journal Article
Antimicrobial Resistance of Salmonella enteritidis and Salmonella typhimurium Isolated from Laying Hens, Table Eggs, and Humans with Respect to Antimicrobial Activity of Biosynthesized Silver Nanoparticles
by
Elsohaby, Ibrahim
,
Abdelfatah, Eman N.
,
El-Gazzar, Nashwa
in
absorption
,
ampicillin
,
antibiotic resistance
2021
Salmonella enterica is one of the most common causes of foodborne illness worldwide. Contaminated poultry products, especially meat and eggs are the main sources of human salmonellosis. Thus, the aim of the present study was to determine prevalence, antimicrobial resistance profiles, virulence, and resistance genes of Salmonella Enteritidis (S. enteritidis) and Salmonella Typhimurium (S. Typhimurium) isolated from laying hens, table eggs, and humans, in Sharkia Governorate, Egypt. The antimicrobial activity of Biosynthesized Silver Nanoparticles (AgNPs) was also evaluated. Salmonella spp. were found in 19.3% of tested samples with laying hens having the highest isolation rate (33.1%). S. Enteritidis) (5.8%), and S. Typhimurium (2.8%) were the dominant serotypes. All isolates were ampicillin resistant (100%); however, none of the isolates were meropenem resistant. Multidrug-resistant (MDR) was detected in 83.8% of the isolates with a multiple antibiotic resistance index of 0.21 to 0.57. Most isolates (81.1%) had at least three virulence genes (sopB, stn, and hilA) and none of the isolates harbored the pefA gene; four resistance genes (blaTEM, tetA, nfsA, and nfsB) were detected in 56.8% of the examined isolates. The AgNPs biosynthesized by Aspergillus niveus exhibit an absorption peak at 420 nm with an average size of 27 nm. AgNPs had a minimum inhibitory concentration of 5 µg/mL against S. enteritidis and S. typhimurium isolates and a minimum bactericidal concentration of 6 and 8 µg/mL against S. enteritidis and S. typhimurium isolates, respectively. The bacterial growth and gene expression of S. enteritidis and S. typhimurium isolates treated with AgNPs were gradually decreased as storage time was increased. In conclusion, this study indicates that S. enteritidis and S. typhimurium isolated from laying hens, table eggs, and humans exhibits resistance to multiple antimicrobial classes. The biosynthesized AgNPs showed potential antimicrobial activity against MDR S. enteritidis and S. typhimurium isolates. However, studies to assess the antimicrobial effectiveness of the biosynthesized AgNPs in laying hen farms are warranted.
Journal Article
Molecular identification of avian influenza virus subtypes H5N1 and H9N2 in birds from farms and live bird markets and in respiratory patients
by
Tolba, Hala M.N.
,
Abou Elez, Rasha M.M.
,
Elsohaby, Ibrahim
in
Amino acid substitution
,
Avian flu
,
Avian Influenza Viruses
2018
Avian influenza viruses (AIVs) have been endemic in Egypt since 2006, and the co-circulation of high-pathogenic avian influenza H5N1 and low-pathogenic avian influenza H9N2 subtypes in poultry has been reported; therefore, Egypt is considered a hotspot for the generation of new subtypes and genotypes. We aimed to characterize AIVs circulating on commercial farms and in live bird markets (LBMs) during the winters of 2015 and 2016 in the study area and to identify H5N1 and H9N2 viruses in respiratory patients.
In total, 159 samples were collected from ducks, pigeons and quails on farms (
= 59) and in LBMs (
= 100) and screened by real-time RT-PCR for H5N1 and H9N2 subtypes. Clinical and postmortem examination was carried out on birds from the farms. Positive H5N1 samples were sequenced and analysed for mutations. Tracheal swabs were also collected from 89 respiratory patients admitted to respiratory hospitals in the same study area.
Overall, H5N1 was identified in 13.6% of birds from farms, while it was detected in 17% of birds in LBMs. Subtype H9N2 was only identified from pigeons on farms (6.5%) and LBMs (11.4%). Sequencing of the haemagglutination gene (HA) in nine representative H5N1 isolates revealed a multi-basic amino acid motif at the cleavage site (321-PQGEKRRKKR/GLF-333), which is characteristic of highly pathogenic AIV, in five of our isolates, while the other four isolates showed an amino acid substitution (Q322K) at this cleavage site to make it (321-P K GEKRRKKR/GLF-333). All the isolates belonged to clade 2.2.1.2, and a comparison of HA sequences at the amino acid level showed 98.8-100% homology among the nine isolates, while they showed 94.1-96.1% identity with reference strains and the commonly used vaccine strain in Egypt. Out of 89 respiratory patients, 3.4% were positive for H5N1 and no patients were positive for H9N2.
Our results indicated the circulation of the endemic H5N1 and H9N2 viruses among poultry in 2015 and 2016. Birds on farms and in LBMs are reservoirs playing a role in the dissemination of the virus and producing a public health risk. The application of proper hygienic measures in farms and LBMs to control the exposure of birds and humans to the source of infection along with continuous monitoring of the circulating viruses will provide information on understanding the evolution of the viruses for vaccine studies.
Journal Article
Genetic Relatedness, Antibiotic Resistance, and Effect of Silver Nanoparticle on Biofilm Formation by Clostridium perfringens Isolated from Chickens, Pigeons, Camels, and Human Consumers
by
Fatma A. El-Gohary
,
Eman Elkhawaga
,
Hala M. N. Tolba
in
Antibiotic resistance
,
antimicrobial properties
,
biofilm
2022
In this study, we determined the prevalence and toxin types of antibiotic-resistant Clostridium perfringens in chicken, pigeons, camels, and humans. We investigated the inhibitory effects of AgNPs on biofilm formation ability of the isolates and the genetic relatedness of the isolates from various sources determined using RAPD-PCR. Fifty isolates were identified using PCR, and all the isolates were of type A. The cpe and cpb2 genes were detected in 12% and 56% of the isolates, respectively. The effect of AgNPs on biofilm production of six representative isolates indicated that at the highest concentration of AgNPs (100 µg/mL), the inhibition percentages were 80.8–82.8%. The RAPD-PCR patterns of the 50 C. perfringens isolates from various sources revealed 33 profiles and four clusters, and the discriminatory power of RAPD-PCR was high. Multidrug-resistant C. perfringens isolates are predominant in the study area. The inhibition of biofilm formation by C. perfringens isolates was dose-dependent, and RAPD-PCR is a promising method for studying the genetic relatedness between the isolates from various sources. This is the first report of AgNPs’ anti-biofilm activity against C. perfringens from chickens, pigeons, camels, and humans, to the best of our knowledge.
Journal Article
Molecular Diagnosis of Persistently Very Virulent Infectious Bursal Disease Virus at Sharkia Governorate, Egypt
by
Awad, Naglaa Fathy Saeed
,
Kotb, Gamelat Kotb Farag
,
Adel, Amany
in
Amino acids
,
Deoxyribonucleic acid
,
Disease
2019
Severeoutbreaks of Infectious bursal disease virus (IBDV) were reported in Egypt despite vaccination. Therefore, this study was conducted to characterize infectious bursal disease (IBD) viruses circulating in Egypt during the period of 2017 - 2018. Sixteen pooled bursal tissue samples were collected from IBD suspected (9 Egyptian balady and 7 broiler) chicken flocks located in different localities at Sharkia governorate, Egypt. These samples were subjected for direct detection of a 620 bp hypervariable region in the VP2 gene using Reverse transcriptase polymerase chain reaction (RT-PCR). The nucleotide and deduced amino acid sequences for VP2 hypervariable region of selected five IBDV field isolates were determined and compared to well characterized reference and vaccine strains worldwide. The IBD virus was detected in 9 out of 16 (56.25 %) investigated chicken flocks. Sequence analysis revealed that the analyzed Egyptian isolates identified as very virulent Infectious bursal disease virus (vvIBDV). The identity between these Egyptian isolates and the vaccine strains is ranged from 89.5%-95.6% and 88.1%-97.8% -at the nucleotide and amino acid sequence levels, respectively. The IBDV-Egy1 isolate is related to the Egyptian vvIBDV strains but with some deviations in the amino acids (259V, 263F, 290I and 302N). There were dramatic differences in the predictive antigenic determinants between these vvIBDV isolates and the classic vaccine strain (Bursin plus). These findings could explain the persistence of vvIBDV circulation in the Egyptian environment in spite of vaccination with classical vaccine strains.
Journal Article
Genetic and Pathogenic Characterization of a Newcastle Disease Virus Isolated from Pigeons in Egypt
by
Farag, Gamelat Kotb
,
Samy, Ahmed
,
Halim, Ahmed Abd El
in
Birds
,
Genotype & phenotype
,
Phylogenetics
2018
GenotypeVI Newcastle disease viruses (NDV), that designated pigeon paramyxovirus 1 (PPMV1) commonly isolated from pigeons (family Columbidae). PPMV1 not only represent a potential threat to pigeon but also it can infect chickens and its virulence enhanced upon passaging in chickens causing clinical signs and deaths. In the present study brain samples were collected from twelve pigeon flocks exhibiting signs of nervousness and diarrhea in a live bird market (LVM) in Egypt. All collected samples were positive for NDV and negative for avian influenza virus and infectious bronchitis virus. Seven positive samples were subjected for genotypic characterization based upon partial F gene sequencing. Partial F gene sequencing revealed that all tested isolates harbor a cleavage site with multi basic amino acid 112KRQKR/F117 characteristic of velogenic strains. However, phylogenetic analysis revealed clustering of all tested strains within sub-genotype VIg. Three isolates were assessed for pathogenicity based upon the mean death time (MDT), the intracerebral pathogenicity index (ICPI) and the intravenous pathogenicity index (IVPI) in chicken. The ICPI and MDT revealed that all tested isolates were of moderate virulence (Mesogenic) in chickens. Mature chickens showed no clinical signs or death as assessed by IVPI. Pigeon in Egypt reared in free rang system and sold in LBM mostly for restocking, that with extensive infection with PPMV represent a potential threat to chickens. Therefore, strict biosecurity measures and control measures at live bird markets, alongside the development of a vaccine may be required to reduce the risk of PPMV1 outbreaks.
Journal Article
Lightweight faster R-CNN for object detection in optical remote sensing images
by
Magdy, Andrew
,
Moustafa, Marwa S.
,
Ebied, Hala M.
in
Compression
,
Computer applications
,
Faster R-CNN
2025
Various applications in remote sensing rely on object detection approaches, such as urban detection, precision farming, and disaster prediction. Faster RCNN has gained popularity for its performance but comes with significant computational and storage demands. Model compression techniques like pruning and quantization are frequently employed to mitigate these challenges. This paper introduces a novel bi-stage compression approach to create a lightweight Faster R-CNN for satellite images with minimal performance degradation. The proposed approach employs two distinct phases: aware training and post-training compression. First, aware training employs mixed-precision FP16 computation, which enhances training speed by a factor of 1.5 to 5.5 while preserving model accuracy and optimizing memory efficiency. Second, post-training compression applies unstructured weight pruning to eliminate redundant parameters, followed by dynamic quantization to reduce precision, thereby minimizing the model size at runtime and computational load. The proposed approach was assessed on the NWPU VHR-10 and Ship datasets. The results demonstrate an average 25.6% reduction in model size and a 56.6% reduction in parameters while maintaining the mean Average Precision (mAP).
Journal Article