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Characterization of Avian Influenza H9N2 and Newcastle Disease Virus Isolated from Vaccinated Chickens in Upper Egypt
2020
Safaa A. A. Abdel-Latif1 | Asmaa Atef2 | Ahmed M. A. Abdel-Aleem3 | AL-Hussien M. Dahshan4 | Ahmed Ali 4
In this study, 50 vaccinated broiler and one layer flock from Beni-Suef, Fayoum and Minia governorates were investigated. Necropsy lesions were suggestive of LPAI-H9N2 or NDV. Samples of tracheal swabs and organs were subjected for viral isolation and molecular characterization. Specific RT-PCR for the NDV F-gene and the HA gene of the LPAI-H9N2 viruses was used. Virus isolation and primary identification using HI test revealed 37.5 and 43.3-46.2% prevalence for LPAI-H9N2 and NDV viruses, respectively. Phylogenetic analysis of partial sequences of the F gene showed that NDV viruses belong to genotype II and VII-1.1. as indicated by the F0 protein proteolytic cleavage site motifs (aa112-117) of the NDV strains F-gene. The vNDV isolates were 98.7-99.3% and 96.6-98.9% identical to each other based on nucleotide and amino acid identities, respectively. Compared to their counterpart isolates; the lentogenic strains shared 98-99.2% and 96.3-98.1% nucleotide and amino acid identities to the LaSota reference strain. The LPAI-H9N2 phylogeny of the HA gene showed that the 2 isolates obtained in this study are related to each other and related to recent 2016-2018 Egyptian H9N2 strains. Notably, the 2 strains showed higher identity (≥99%) to recent Israeli 2018 isolates with several amino acid changes. The current study revealed wide spread of both NDV and LPAI-H9N2 viruses. The vaccine failure and the mismatch between the vaccine and circulating NDV viruses is the most probable cause of current outbreaks. The LPAI-H9N2 viruses are divergent form their ancestral viruses in Egypt indicating continuous circulation and vaccine pressure induced mutations
Afficher plus [+] Moins [-]Phenotypic and Molecular Characterization of Ornithobacterium rhinotracheale Isolates in Broiler Chickens
2020
Ahmed Hassan | Mennat-Allah Medhat | Mostafa Shahata | Aml Bekheet
Ornithobacterium rhinotracheale (ORT), is a bacterium that cause respiratory tract infection, has led to significant problems in the intensive poultry production. The current study aimed to isolate and identify ORT from broiler chickens, to detect antibacterial sensitivity and resistance of ORT isolates, and to test experimental infection of ORT in broiler chickens. One hundred eighty samples including tracheas, lungs and air sacs were subjected to isolation and phenotypic identification. Twelve suspected ORT isolates were used for molecular identification. Agar gel precipitation test was used to determine serotype of ORT isolates. Antibacterial sensitivity and resistance of ORT isolates were tested against 14 antibacterial drugs using standard disk diffusion technique. Pathogenicity of ORT was tested by experimental infection in broiler chickens. Results revealed that the incidence of ORT infection in broiler chickens in Assiut Governorate is 17.77% using isolation and phenotypic methods of identification, while it is 3.33% using molecular identification. Serological identification of ORT isolates indicated that all tested isolates, were belonged to serotype A. All ORT isolates were resistant to gentamycin, amoxycillin and cephradine with 100% incidence, where, 100% isolates were sensitive to colistin and doxycycline, 50% of isolates were sensitive to ampicillin and streptomycin, and 16.67% of isolates were sensitive to neomycin and trimethoprim. Living Newcastle attenuated vaccine, Lasota vaccine, exaggerates the clinical signs and lesions of ORT experimental infection.
Afficher plus [+] Moins [-]Ovsynch Produced Larger Follicles and Corpora Lutea of Lower Blood Flow associated Lower Ovarian and Uterine Blood Flows, Estradiol and Nitric Oxide in Cows
2020
Elshymaa Ahmad Abdelnaby | Amal Mahmoud Abo El-Maaty | Refaat Ragab | Adel Seida
The use of ovsynch and its modifications for synchronizing estrous cycle and ovulation in ruminants is widely used with lowered conceptions rates. This study aimed to investigate the follicular (F1) and the corpus luteum (CL) hemodynamics, ovarian (OvA) and uterine arteries (UtA) blood flow volumes (BFV) and dynamics associated with the circulating estradiol (E2), progesterone (P4), glucose and nitric oxide (NO) in cows treated with the ovsynch protocol. Eight Friesian cows underwent trans-rectal Doppler scanning and blood sampling each other day throughout two successive non-treated (Spontaneous) and two treated successive estrous cycles (ovsynch). The results revealed that the existed dominant follicles (F1) area, antrum area, color area, and the CL area and the color area on the ovaries declined following the first dose of the gonadotropin-releasing hormone (GnRH, Day-11) till Day -5 then another dominant follicle started growth and reached ovulation (Day 0). Ovsynch pre-ovulatory phase (Day-5 to 0) had more (P<0.01) small, medium, and total follicles. The ovsynch F1 (P=0.001) and the CL (P=0.006) had higher areas but lower color areas percent. The ovsynch increased ipsi-lateral OvA pulsatility index (PI) that associated decreased diameter and time average mean velocity (TAMV) and blood flow volume except Day 6 (BFV, P<0.05). The ovsynch improved (P<0.01) the ipsilateral UtA PI but lowered its diameter, peak systolic velocity (PSV), TAMV, and BFV except Day 10. Ovsynch ovulation was characterized by low E2, NO, and high glucose but the late luteal phase had high (P<0.001) P4 and glucose with low E2. In conclusion, the decreased follicle and luteal vascularization with lowered uterine blood flow and estradiol may adversely affect the quality of the oocyte and the decreased progesterone from Day 7 till Day 10 and the ipsilateral uterine artery BFV may not support the implantation and disturb the maintenance of the embryo after timed insemination.
Afficher plus [+] Moins [-]State-of-the-art and Emerging Technologies for In Vitro Embryo Production in Buffaloes
2020
Satish Kumar | Otávio Ohashi | William Vale | Luciana Melo | Vicente Freitas
Buffalo is a multipurpose and economically important animal due to the demand for its products (milk and meat). Thus, the use of reproductive biotechnologies is important to maximize the diffusion of genetically superior dams and sires. After the unsatisfactory results of the Multiple Ovulation and Embryo Transfer, the combined effect of ovum pick-up from live animals and in vitro embryo production (IVEP) has great potential to dissemination of selected genetics in buffalo herds, contributing to an increase in meat and milk production. During the past two decades, considerable advances have been made in IVEP following continuous scientific effort, but at the moment their cost is not satisfactory for commercial purpose. This technique is refined day by day in order to improve the buffalo embryo quality. Thus, the objective of this paper was to review the state-of-art in IVEP, as well as discussed the emerging technologies that can contribute to improving the results of this technology in buffalo species.
Afficher plus [+] Moins [-]Gross, Light and Scanning Electron Microscopic Studies on the Ampulla Ductus Deferentis of Dromedary Camel with Special Reference to its Seasonal Variations
2020
Abdelmohaimen Mostafa Saleh | Ramy K.A. Sayed | Hazem Hamoda
The morphological structure and morphometrical features of the ampulla ductus deferens of the adult camels were studied by light and scanning electron microscopy to get better understand with its seasonal variations. The wall of ampulla was composed of mucosa, submucosa, muscularis and serosa or adventitia. It was lined by pseudostratified columnar epithelium containing intraepithelial glands. The lamina propria and tunica submucosa formed together the thickest part of the ampullary wall. The ampullary glands were branched tubulo-alveolar, with diverticulae-like appearance and occupied mostly the lamina propria- submucosa. Each gland consisted of peripheral wide and central narrow alveoli that were lined by simple low columnar or cuboidal epithelium and mostly contained spermatozoa and secretory materials. The gland opened in the ampullary lumen by short tubule, which was lined by pseudostratified columnar epithelium. Histochemically, the epithelial cells reacted positively to Alcian blue, PAS and sudan black stains and negatively to the Best's carmine stain, indicating the presence of the acid, neutral glycoprotein and fatty droplet, as well as absence of the glycogen. Morphometrically, the height of the luminal and glandular epithelia, thickness of the lamina propria- submucosa and ratio of the glandular to the connective tissue showed seasonal variations. The height of the luminal and glandular epithelia reached their maximum values in winter and decreased gradually throughout spring and recorded the lowest values in summer. Scanning electron microscopy revealed various shaped openings in the luminal surface of the ampulla. The cells apices were studded with short microvilli and many secretory granules or vesicles. The ampullary glands appeared as a network of diverticulae-like structure, which occupied mostly the lamina propria-submuosa. The cells apices of the glandular epithelium were stereo-ciliated, microvilliated cells or showed central bleb-like protrusion surrounded by thin long microvilli. The glandular alveoli contained spermatozoa and secretory materials. In conclusion, the camel ampulla ductus deferentis performs a storage function in addition to its secretory one, where both are subjecting to seasonal variations.
Afficher plus [+] Moins [-]Effect of the Enzymatic Fungal Extract of Pochonia chlamydosporia on the Viability of Fasciola hepatica eggs
2020
Lorena Souza Castro | Isabella Vilhena Freire Martins | Victor Menezes-Tunholi Alves | Fernanda de Paula Roldi Vieira | Gabriella Peterlini Tavares | Jackson Victor Araújo
Hepatic fasciolosis has been implicated as one of the most important parasitic diseases affecting the sanity of cattle and sheep, reflecting in significant economic losses besides being an important anthropozoonotic disease. The eggs of Fasciola hepatica are eliminated with the feces of these hosts, and under the influence of extrinsic and intrinsic factors may remain in the environment for months until they find favorable conditions for embryogenesis. The objective of the present study was to evaluate the viability of Fasciola hepatica eggs exposed for 60 minutes at different concentrations of the enzymatic extract of Pochonia chlamydosporia (Pc-10). Subsequently, they were sedimented and placed on 24-well plates containing the extract of P. chlamydosporia (Pc-10) at concentrations of 500 μL (10%), 400 μL (8%), 300 μL (5%), 200 μL (2%), 100 μL (1%) and distilled water (control group). The experiment was carried out in triplicate, using a total of 900 eggs. After the experimental exposure to the enzyme extract of the fungus (Pc-10), 98% of the eggs exposed to the enzymatic solution demonstrated significant ultrastructural alterations in their respective teguments, when observed in scanning electron microscopy and transmission. The ultrastructure showed a collapse of the internal walls of the egg, interfering in the opening of the operculum. The use of the enzymatic extract of P. chlamydosporia (Pc-10) compromised both the external tegument, breaking it and pasting it, as well as vital structures of the embryonic activity of the F. hepatica eggs.
Afficher plus [+] Moins [-]Morphological and Molecular characterization of Sarcocystis arieticanis from the Heart Muscles of Domestic sheep, Ovis aries, in Qena, Upper Egypt
2020
Nermean Moamen Hussein
This study examined Sarcocystis spp., cyst forming coccidians whose intermediate hosts include sheep, an important source of meat in Egypt. Samples of heart muscles were collected from 110 sheep from different localities in Qena, Upper Egypt, and examined for Sarcocystis spp. by macroscopic evaluation, light microscopy, transmission electron microscopy, and molecular tests. All the sarcocysts found [in 52 of 110 sheep (47.27 %)] were thin-walled (0.32–0.44 µm) and measured 78.56–146 µm in length and 33.12–73 µm in width . The cyst walls possessed irregularly branched protrusions (0.67–1.4 µm × 0.05–0.26 µm) with rounded vesicles at their base that were underlin by a thin layer of ground substance (0.14–0.26 µm). Septa derived from the ground substance divided the cysts into many compartments that contained cystozoites of different developmental stages and fully formed banana-shaped bradyzoites, for which descriptions are provided based on transmission electron microscopy. Comparison of the 18S rRNA sequence of the sarcocysts against those of previously identified species in mammals deposited in GeneBank was performed. The phylogenetic tree clustered the Sarcocystis specimens in this study within the S. arieticanis clade. In addition, the macroscopic Sarcocystis spp. (S. moulei and S. gigantea) aggregated together at some distance from the microscopic Sarcocystis spp. (S.capracanis, S. hiricicanis, S. tenella, and S. arieticanis) regardless of differences in the intermediate host, indicating the importance of Sarcocystis cyst size as a characteristic taxonomic feature.
Afficher plus [+] Moins [-]Gastrointestinal Helminthic Infections in Egyptian Domestic Camels, Camelus dromedarius, with a Special Reference to Trichostrongylids
2020
Khaled Mohamed El-Dakhly | Waleed M. Arafa | Lilian N. Mahrous | Alaa M. Yousef
In Egypt, scare literature explored the coprological examination of domestic camels. Therefore, a total of 626 fecal samples from domestic dromedaries, Camelus dromedaries, permitted to slaughtering in El-Warrak abattoir, Giza were taken. Coproparasitological investigations including sedimentation and floatation techniques, fecal culture and larval identification were done. The overall prevalence of parasitic infections was 41.53%. Fifteen species of helminth eggs/protozoan oocysts were recovered. The prevalence of helminths was 28.11% (176/626) and that of protozoa was 5.59% (35/626). Mixed infections were reported in 7.82% (49/626) of camels. The revealed trematode was Fasciola sp. (1.12%), tapeworms belonged to Anoplocephalids (5.27%), protozoan oocysts were Eimeria cameli, E. dromedarii, E. rajasthani (11.02% for all Eimeria spp.) and Buxtonella sp. (0.32%). The recovered nematodes belonged to Trichuris sp. (1.92%) and trichostrongyles (31.0%). Coproculture of the later revealed the presence of 8 species; Trichostrongylus axei, Tr. colubriformis, Chabertia ovina, Ostertagia ostertagi, Haemonchus sp., Oesophagostomum sp., Bunostomum sp. and Nematodirus sp. Morphometric characteristics of larvae were recorded. Age and seasonal variations revealed significant (P≤0.05) differences among examined camels. Animals aged more than 5 years had the highest infections rate (45.96%; 199/433) and nematodes were the significantly (P≤0.05) predominant. In winter, the highest prevalence (60.67%; 108/178) was recorded. Oppositely, sex had no significant differences. Due to the expected important role played by imported camels in transmitting various parasitic infections, veterinarians and parasitologists are extremely advised to apply further studies on the helminth fauna, particularly gastrointestinal nematodes, of both domestic and imported camels, by the use of traditional and molecular tools.
Afficher plus [+] Moins [-]Serological survey of Ehrlichia canis, Babesia canis and Leishmania infantum in a Brazilian canine population
2020
Tainá Luana Vieira Lopes Zuchi | Luciana Corassa | Gustavo Bonetto | Cláudia Luana Lopatini | Júlia Balena Spricigo | Soraya Regina Sacco Surian | Diogenes Dezen | Joice Lara Maia Faria
Este estudo avaliou as ocorrências de babesiose, erliquiose e leishmaniose e a presença de coinfecção por essas doenças em cães do município de Concórdia, no oeste do estado de Santa Catarina (SC), Brasil. O sangue foi coletado de 424 cães atendidos no Centro de Prática Clínica do Instituto Federal de Santa Catarina, Concórdia, e também em clínicas da cidade e de sua zona rural. A presença de anticorpos contra Leishmania infantum foi investigada pela reação de Imunofluorescência Indireta (IIF) e contra Babesia canis e Ehrlichia canisusando o ensaio imunoabsorvente ligado a enzima (ELISA). O teste do qui-quadrado, ao nível de significância de 5%, foi utilizado para comparar os animais positivos e negativos na população amostrada. Das 424 amostras avaliadas, 170 (40,09%) foram positivas para erliquiose, 178 (41,98%) foram positivas para babesiose e 59 (13,91%) foram positivas para leishmaniose. Houve diferenças estatísticas quanto à erliquiose em relação às variáveis de área, acesso à rua e raça. Além disso, entre as amostras positivas, houve reações de co-infecção. A partir desses resultados, pode-se sugerir que essas três doenças estão presentes no município de Concórdia, SC.
Afficher plus [+] Moins [-]Assessment of the Endocrine Cells and Neural Structures in the Abomasum and Pancreas of Dromedary Camel based on their Synaptophysin Immunoreactivity
2020
Ahmed M. Abdellatif
Endocrine cells of the gastrointestinal tract are located mainly within the pancreatic islets and throughout the wall of the stomach and intestines. These cells regulate several body functions via release of hormones. Synaptophysin is a transmembrane glycoprotein expressed in almost all types of endocrine cells as well as in synaptic vesicles of neurons. Nevertheless, the distribution of synaptophysin-immunoreactive (SYP-IR) cells in abomasum and pancreas of camel has not been described. In the present study, SYP immunoreaction was assessed in different regions of abomasum and pancreas of dromedary camel using SYP immunostained sections. SYP-IR endocrine cells of both closed- and open-types were observed within cardiac, fundic, and pyloric gland regions of the abomasal mucosa. Significantly higher number of SYP-IR cells were evident within the fundic and pyloric gland regions compared to cardiac gland region. Moreover, SYP labelled nerve fibers located within abomasal lamina propria and cells and fibers of the submucosal and myenteric nerve plexuses. In pancreas, SYP intensely labeled almost all cells of pancreatic islets. SYP-IR endocrine cells were also observed within the lining epithelium of pancreatic acini and ducts. In addition, SYP intensely stained cells and fibers of intrapancreatic ganglia. A moderate SYP immunoreaction was seen within the perivascular and periductal nerve fibers as well as those fibers supplying the pancreatic acini and ducts. These findings advance our understanding of the normal distribution of the gastro-pancreatic endocrine cells in camel. Future studies are needed for further characterization of hormones produced by these cells and their clinical relevance in camel.
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