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Seroprevalence of Babesia ovis in small ruminants in Siwa Oasis, Egypt
2007
H. I. Hosein | Samia A. Ahmed | F. A. Ibrahim | T. R. Abou-Elnaga | M. A. Gebely | Mona A. Mahmoud
Seroprevalence of Babesia ovis in sheep and goats was studied in Siwa Oasis between January 2002 and January 2003. A total of 240 blood samples were collected from 108 sheep and 132 goats for preparation of blood smears and for separation of serum samples and tested against B. ovis by using IFAT. B. ovis was detected in 55 (50.92%) and 59 (44.69%) blood smears examined in sheep and goats, respectively. The overall prevalence of B. ovis infection was 71.3% in sheep and 68.2% in goat using IFAT. The seasonal prevalence of B.ovis peaked in both spring and summer as revealed by blood smear examination and IFAT. A total of 143 ticks were collected from 62 sheep and 81 goats during the study. The ticks examined were Rhipicephalus turanicus (75.52%) and Hyalomma anatolicum (24.48%).
Mostrar más [+] Menos [-]The role of corynebacterial phospholipase D vaccine in activation of macrophages
2007
A.K. Ibrahim | F.R. El-Seedy | W.H. Hassan
The role of phospholipase D toxoid (PLD) vaccine in enhancing killing activity of macrophages was demonstrated in this study. Four groups of Balb/c mice were vaccinated with different forms of current vaccines against Corynebacterium pseudotuberculosis (C. pseudotuberculosis). The first group was vaccinated with purified recombinant mutated PLD protein adjuvated vaccine; the second with formalin inactivated whole cells of C. pseudotuberculosis adjuvated vaccine, the third group with combined bacterin-toxoid adjuvated vaccine and the fourth was given viable C. pseudotuberculosis cells. Mononuclear peritoneal cells from each vaccinated groups were collected and inoculated intraperitoneally into naïve recipient Balb/c mice that were subsequently challenged by equal number of live C. pseudotuberculosis cells. Killing activity of peritoneal macrophages collected from each recipient group of mice was assayed by cultivation of lysed macrophages on plates of count brain heart agar. It was reported that the highest killing activity of macrophages were those collected from mice vaccinated with recombinant PLD adjuvated vaccine that reaches 95% of phagocytosed C. pseudotuberculosis living bacteria; where those given viable C. pseudotuberculosis bacteria (80%); then combined vaccine (69.5%) and the least killing activity was performed by macrophages obtained from bacterin vaccinated animals
Mostrar más [+] Menos [-]Toxo-pathological effects induced by urea in broiler chicks
2007
K. A. Abdou | M. Mubarak | A. A. Sharkawy
Sixty, day-old, chicks were reared up to 3 weeks of age and then randomly divided into 4 equal groups (3 treated and one control group). Urea (46 % nitrogen) was added to the grower-finisher ration of the treated birds at levels of 1% , 3% and 5% (groups I, II & III respectively). Feed and water were available ad libitum for all birds over the time of experiment. At days 7, 20 and 30 post exposure, 5 birds from each group were weighed, bled and sacrificed. All birds spontaneously died during the experiment were also necropsied. Haematological parameters (RBCs, WBCs counts, PCV and Hb), biochemical variables [urea, glucose, uric acid, alkaline phosphatase; (ALP) and lactate dehydrogenase; (LDH)] and body weight gain were assessed. The encountered pathological changes were described. The obtained results indicated that: (1) decrease in RBCs, WBCs counts, PCV and Hb, (2) increase in ALP, LDH, urea and uric acid, while glucose level was decreased. (3) decrease in body weight gain in all treated birds. There were significant pathological changes in kidneys, heart, liver and lungs of the treated birds. It was concluded that addition of urea to poultry feeds to replace the more expensive protein-nitrogen has serious consequences which affect the health condition and weight gain of birds.
Mostrar más [+] Menos [-]Effect of sulphadoxine-trimethoprim combination on some pharmacokinetic aspects of sulphadoxine in goats
2007
H.A.H. Zaghloul | A.A.M. El-Gendy | M.A. Tohamy | Abeer M. Radi
Some pharmacokinetic aspects of sulphadoxine alone and sulphadoxine-trimethoprim (TMP) combination were studied in goats following single intravenous (i.v) and intramuscular (i.m) administration of 15 mg kg–1 b.wt. After i.v injection the serum sulphadoxine concentration time course was best described by two compartment-open model with distribution half-lives (t0.5(.)) 2.48 and 2.31 h., elimination (t0.5(3)) half-lives 23.10 and 24.75 h., total body clearance (ClB) 0.076 and 0.073 L kg-1 h.-1 and steady state volume of distribution (Vdss) 368.54 and 411.73 ml kg-1 for sulphadoxine alone and sulphadoxine-trimethoprim combination, respectively. After i.m administration the mean peak serum concentrations (Cmax) 25.69 and 33.31 ug ml–1 were achieved after maximum time (tmax) of 3.09 and 2.79 h. for sulphadoxine alone and sulphadoxinetrimethoprim combination, respectively. The absorption half-lives (t0.5(ab)) were 0.58 and 0.42 h., respectively. It is concluded that a combination of sulphadoxine and TMP can provide a synergistic level for both antimicrobials and thus be a useful combination in the treatment of various goat diseases.
Mostrar más [+] Menos [-]Prevalence and determinants of <i>Cryptosporidium</i> spp. infection in smallholder dairy cattle in Iringa and Tanga Regions of Tanzania
2007
E.S. Swai | N.P. French | E.D. Karimuribo | J.L. Fitzpatrick | M.J. Bryant | D.M. Kambarage | N.H. Ogden
The prevalence of Cryptosporidium spp. infection in a cross-sectional study of dairy cattle, from two contrasting dairying regions in Tanzania, were determined by staining smears of faecal samples with the modified Ziehl-Neelsen technique. Of the 1 126 faecal samples screened, 19.7% were positive for Cryptosporidium spp. The prevalence was lower in Tanga Region than in Iringa Region. The prevalence of affected farms was 20% in Tanga and 21% in Iringa. In both regions, the probability of detecting Cryptosporidium oocysts in faeces varied with animal class, but these were not consistent in both regions. In Tanga Region, Cryptosporidium oocysts were significantly more likely to be found in the faeces of milking cows. In Iringa Region, the likelihood that cattle had Cryptosporidium-positive faeces declined with age, and milking cattle were significantly less likely to have Cryptosporidium positive faeces. In this region, 7% of cattle were housed within the family house at night, and this was marginally associated with a higher likelihood that animals had Cryptosporidium-positive faeces. Our study suggests that even though herd sizes are small, Cryptosporidium spp. are endemic on many Tanzanian smallholder dairy farms. These protozoa may impact on animal health and production, but also on human health, given the close associations between the cattle and their keepers. Further studies are required to assess these risks in more detail, and understand the epidemiology of Cryptosporidium spp. in this management system.
Mostrar más [+] Menos [-]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
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
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