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Light and electron microscopy of Paranella diplodae N. SP. (Polyopisthocotylea;Microcotylidae; Monogenea ) from some Red Sea Teleost fishes in Egypt
2007
E. M. Bayoumy | O. K. Abd El-Hady | M. A. Hassanain
The present study deals with a monogenean parasite infecting, some marine fish through light and scan electron microscopy. It revealed that the percentage of infection was 48% (14 out of 50 fish), 28% (14 out of 50 fish), 22% (11 out of 50 fish) and 16% (8 out of 50 fish) in Diplodus noct, Gerres oyena, Lethrinus elongates and Siganus revulatus, respectively. The present work recorded Paranaella diplodae (Polyopisthocotylea; Microcotylidae; Monogenea) as a new species collected from the investigated fish gills. They are lanculate flukes, the haptor is not distinguished from the body proper approximately 1/3 of the whole body length. The surface topography of the parasite bears small pits and conspicuous transverse folds and richly supplied with papillae-like unicellate sensory ending. The opisthohaptor is typical of Microcotylidae. The clamp structure and the haptoral tegument are similar to the rest of the body
Afficher plus [+] Moins [-]Characterization of Variant Strain of Newcastle Disease Virus in Egypt
2007
A. S. Abdel-Moneim | Azza A. El-Sawah | M. A. Kandil
During 2005, velogenic Newcastle disease virus (NDV) caused a major outbreak among commercial broiler chicken in Egypt. The outbreak raised concerns regarding the protective immunity of commercially available vaccines for prevention and control of this virus in poultry. The virus was isolated from broiler farm suffered from more than 95% mortalities. The isolate was confirmed not to be avian influenza virus (AIV) by rapid chromatographic strip test, and characterized as NDV using reverse transcription-polymerase chain reaction (RT-PCR) which amplified a portion of the fusion gene of NDV and haemagglutination inhibition (HI) test. This isolate confirmed to be velogenic viscerotropic NDV by mean death time (MDT) test and pathogenicity to 7-week old chickens. We tried to determine whether the existing commercial live NDV La Sota vaccine could provide protection against the isolated virus or not. Birds received a single dose of live La Sota type vaccine at 3 weeks of age and were challenged 2 weeks postvaccination with a lethal dose of NDV. Results indicated that the live vaccine did not protect against morbidity but reduced mortality in comparison to controls. All unvaccinated control chickens challenged with NDV died within 5 days post-challenge (pc). Protection from disease did not correlate with the presence of antibody titers (determined by HI) at day of challenge. These results underscore the need to develop new NDV vaccines and vaccine strategies for use during outbreak situations to protect birds from both disease and infection and to reduce virus shedding.
Afficher plus [+] Moins [-]Effect of high water temperature on natural resistance of cultured Oreochromis niloticus
2007
M. N. M. Ali
Killing activity of fresh Oreochromis niloticus serum was used as an indicator of the natural immunity. Serum killing activity was tested in temperature stressed fish exposed to 32 ±1°C to different Pseudomonas fluorescens strains. As a clinical estimate of natural immunity and disease resistance, experimental challenge with P. fluorescens strains was conducted. The results cleared that serum killing activity at 32±1°C was almost stopped where fish got infected after bacterial challenge. On the other hand, control fish group kept at 23± 1°C developed serum killing activity and resistance to the acquisition of infection after challenge. A correlation was found between resistance activities of P. fluorescens strains to serum killing and their corresponding courses of infection after bacterial challenge. However, the results of experimental challenge conducted at 32±1°C suggested that the immunocompromising state resulted from the stress of inability to withstand high water temperature is exclusively the critical aspect for the induction of infection.
Afficher plus [+] Moins [-]Influence of dipping practices on the seroprevalence of babesiosis and anaplasmosis in the foot-and-mouth disease buffer zone adjoining the Kruger National Park in South Africa
2007
K.B. Stevens | A.M. Spickett | W. Vosloo | D.U. Pfeiffer | E. Dyason | B. Du Plessis
A serological survey of bovine babesiosis and anaplasmosis was conducted in the foot-and-mouth disease buffer zone surrounding the Kruger National Park in South Africa between 2001 and 2003 to determine whether the withdrawal of government-subsidized dipping in certain regions had affected the seroprevalence of these tick-borne diseases. Seroprevalence of Anaplasma marginale and Babesia bovis increased during the study period. This increase was greater in Limpopo Province where farmers had to supply their own acaricide than in Mpumalanga Province where dipping materials were provided by the local Veterinary Services. The number of animals testing positive for B. bigemina decreased in both provinces during the study period, which was attributed to possible vector displacement rather than more effective tick control measures. Responses to a questionnaire on ticks and tick-borne diseases revealed local knowledge on the subject to be highly variable and sometimes incorrect.
Afficher plus [+] Moins [-]Protein analysis for comparison between Salmonellae isolated from different poultry species
2007
Seham A. El-Zeedy | Hussein K. Eldeen | Jihan M. Badr
A total of 620 egg samples from different species (chickens, ducks and ostriches) and 1615 poultry samples (chickens, ducks, pigeons, quails, turkeys and ostriches) were examined for salmonella infection. 12 salmonella isolates were obtained from the egg samples (1.9%) and 67 isolates from poultry samples (4.1%). Salmonella isolates were serotyped into S. enteritidis (25 isolates), S. typhimurium (17 isolates), S. infantis (12 isolates), S. montivideo (7 isolates), 3 isolates for each of S. rubislaw and S. cerro , 2 isolates for each of S. virginia, S. agona, S. poona, and S. derby and 1 isolate for each of S. sandiago and S. kentucky. The incidence of isolation from different poultry species was discussed in details. Antibiogram of the isolated salmonellae against 10 different antibiotics revealed that norofloxacin, ciprofloxacin, cepheridin and gentamycin gave the highest activity against different salmonella isolates while amoxicillin, tetracycline, and nitrofurantoin showed the highest resistance rate. Pathogenicity of the isolated serovars was tested in chickens. All isolates were found pathogenic with various degree of virulence. SDSPAGE protein analysis for the salmonella isolated form different poultry species revealed 12 protein bands ranged from 22-289 kDa. The differences were insufficient for reliable differentiation between the isolates and accordingly, it could be used beside other molecular techniques in differentiation between the salmonella strains.
Afficher plus [+] Moins [-]Trial to increase the sensitivity of Brucella antigens treated with Binary ethylene imine as inactivated agent
2007
Hussein K. Eldeen | Salwa S. Awad
kills Brucella cells by causing lysis of the membrane, so the phenol-heat killed brucella antigen may lake specificity as a result of destruction the majority of proteins in the cell wall. Accordingly, attention was directed to produce antigen using binary ethylene imine as an inactivator. The produced antigen showed high specificity in detecting Brucella abortus and Brucella melitensis-infected animals, but sensitivity was not affected in comparison with the standard Rose Bengal antigen. In Enzyme immunotransfer blot (EITB), phenol–heat killed brucella cells showed only 3 bands (37.375, 23.47 and 7.83 kDa) that denotes denaturation for at least 6 bands whereas binary inactivated brucella cells showed similarity with non-treated ones
Afficher plus [+] Moins [-]Some studies on enteric parasites of sheep in Beni-Suef Governorate
2007
S. M. Abo El Hadid | H. S. Lotfy
This work was carried out in four selected provinces in Beni-Suef Governorate, Egypt to investigate the possibility of existence of different types of enteric parasites infect 2-5 years old sheep and estimate the rate of improvement in some of its productive parameters post eradication of these parasites in relation to each parasitic infection. The study cleared that gasterointestinal bursated nematodes (Haemonchus spp., Trichostrongylus spp., Ostertagia spp., Nematodirus spp. and Cooperia spp.) and Fasciola are the most common parasites infecting sheep (57.44% & 48.44% respectively), this was followed by Paramphistopmum infection (38.88%), Moniezia spp. (33.11%), different types of Eimeria spp. (29%) and finally Trichuris spp (7%). Fecal culture of positive samples demonstrate presence of five types of nematode larvae include Haemonchus spp. larvae (33.75%), Oestertagia spp. (31.5%), Trichostrongylus (11.75%), Cooperia spp. (14.5%) and Nematodirus spp. (8.5%). Using of ivermectin for treatement of GIN, Nitroxynil for treatment of Fasciola, and oxyclozanide for treatment of Paramphistomum species infection, induce marked decrease in the mean number of different eggs per gram (e.p.g.) of faeces associated with improvement in mean body weight gain (5.71 Kg) and rate of lambing (26.77) after 6 months post treatment. High rate of improvement post treatment was recorded in animals originally free from Fasciolia infection, also and that harboring low e.p.g. than animals of high e.p.g. Finally it was evident that high rate of improvement was cleared in animals less than 4 years old in comparison by that over 4 years old
Afficher plus [+] Moins [-]Treatment trials of Pseudomonas aeruginosa infection in quails
2007
Jihan M. Badr | A. S. E. D. Metwali | Amal I. Yoseif | M. M. Arafa
Two experiments were carried out to evaluate the efficacy of the administration of active dry yeast and/or lactobacillus preparation (AVI-BAC), either before or after the infection with antibiotic resistant field strain of Escherichia coli O127 (E. coli O127) in controlling the severity of infection in quail chicks. The quail chicks of the different experimental groups were infected orally for two successive days with 3x107 CFU of E. coli O-127 as an individual dose. The used field strain proved to be highly pathogenic for quails. Probiotics were supplemented in the drinking water for the different treatment groups at a dose level of 0.5 gm/L. The results revealed that the inclusion of lactobacilli or active dry yeast before E. coli infection has been highly effective in reducing mortality rate, organ invasion and the number of E. coli positive quail chicks. In addition, it decreased the severity of macroscopic and microscopic lesions in different organs in the probiotic treated groups as compared to the infected controls. Lactobacilli preparations were more efficient in controlling the severity of the infection. On the other hand, the administration of yeast and /or lactobacilli after inducing E. coli infection reduced the mortality rate and the severity of lesion score in different organs but probiotics failed to protect quail chicks against the infection. It has been proved that the two probiotics have synergistic effect in controlling collibacillosis in quails.
Afficher plus [+] Moins [-]Ultrasonography of normal , cystic and dysplastic kidney in cattle
2007
M. M. Seif | H. A. Bakr
Thirty four apparently healthy cattle (9 males and 25 females) of mixed breed (Balady X Friesen) were selected for ultrasonographic investigations in this study. Ultrasonographic measurements of vertical and horizontal diameters of kidney, the diameters of the renal parenchyma and the diameter of renal sinus were determined in the middle of right and left kidneys. Twenty nine cattle (9 males and 20 females), had normal ultrasonographic appearance of both right and left kidney while the other five cows had some pathological affections including cystic kidney and renal dysplasia in their left kidneys . The vertical diameter of the right kidney was (4.84±1.18 cm) , the horizontal diameter (9.16 ± 1.35 cm) , and the vertical diameter of the renal sinus was ( 3.54 ± 1.02 cm ) . The thickness of the renal cortex and medulla ( renal parenchyma) was (2.16 ± 0.46 cm ). On the other hand ,the vertical diameter of the left kidney was (5.89 ±1.13 cm), and the vertical diameter of the renal sinus was ( 3.83 ± 1.12 cm ). The thickness of the renal cortex and medulla (renal parenchyma) was (2.46 ± 0.35 cm ). It was concluded that the ultrasonographic values determined in this study can be used as references for the diagnosis of morphologic changes in the kidney of domestic dairy cattle
Afficher plus [+] Moins [-]Comparative pharmacokinetic and renal clearance study of ceftiofur in cross breed Friesian and Buffalo calves
2007
A. A. M. El-Gendy | M. A. Tohamy | M. Ismail
The pharmacokinetic profile of ceftiofur sodium, a third generation cephalosporin, was studied in both Friesian and buffalo calves following a single intravenous and intramuscular administration of 2.2 mg kg-1 b.wt. in a cross over study with 15-day wash out period. After i.v administration the serum concentration-time curve of ceftiofur sodium was best fitted using two-compartments open model, with distribution half-lives (t½(()) of 0.384 and 0.176 h., elimination half-lives (t½(0)) of 5.047 and 1.607 h., mean residence time (MRT) of 6.926 and 2.072 h., volumes of distribution at steady-state (Vdss) of 0.206 and 0.134 L kg-1 and total body clearance (ClB) of 0.029 and 0.065 L kg-1 h-1 in Friesian and buffalo calves, respectively. Following intramuscular administration, the drug absorbed with half-lives of absorption (t½(ab)) of 1.010 and 0.217 h., maximum serum concentrations (Cmax) of 5.539 and 9.663 g ml-1 which attained after (tmax) of 3.147 and 0.825 h. and the drug was eliminated with half-lives (t½(el)) of 5.239 and 1.750 h. in Friesian and buffalo calves, respectively. The systemic intramuscular bioavailabilities were 89.82 and 99.7 %, while the in-vitro serum proteinbinding tendencies were 39.68 and 14.44 % in Friesian and buffalo calves, respectively
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