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Occurrence of multiple drug resistance in <i>Trypanosoma brucei rhodesiense</i> isolated from sleeping sickness patients
2007
N. Maina | J.M. Kagira
The occurrence of cross-resistance among melarsoprol-resistant Trypanosoma brucei rhodesiense isolates was investigated in this study. The isolates, T. b. rhodesiense KETRI 237, 2538, 1992, 2709, 2694 and 3530, had been obtained from sleeping sickness patients in Kenya and Uganda between 1960 and 1985. Five groups consisting of six mice each were inoculated intraperitoneally with 105 parasites of each isolate, and 24 h later treated with either melarsoprol, homidium chloride, diminazene aceturate or isometamidium chloride. The control group comprised infected but untreated mice. The mice were monitored for cure for a period of 60 days post-treatment. The mean prepatent period in the control mice was 5 days while the mean survival period was 22 days. Five of the stabilates, KETRI 237, 2538, 2709, 2694, and 3530, were confirmed to be melarsoprol resistant. Cross-resistance was observed, with the majority of the isolates being resistant to homidium chloride (5/6) and diminazene aceturate (5/6), but all were sensitive to isometamidium chloride (6/6). However T. b. rhodesiense KETRI 1992, which was previously considered as melarsoprol resistant, was sensitive to all the drugs tested. In conclusion, our study has revealed the existence of cross-resistance among the melarsoprol resistant isolates which could only be cured by isometamidium.
显示更多 [+] 显示较少 [-]Evaluation of Lactobacilli and active dry yeast in the prevention and control of quail colibacillosis
2007
A. S. E. D. Metwali | Jihan M. Badr | Amal I. Yoseif
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.
显示更多 [+] 显示较少 [-]Preparation and evaluation of kits for detection of antibodies of Pasteurella multocida
2007
Zeinab M. Souror | A. A. Badawi | Hanan M. Ibarahim
Polyclonal hyperimmune serum against Pasteurella multocida type A:5, A:8 and A:9 was prepared in boskat rabbits. The indirect haemagglutination test (IHT) showed that such serum had an antibody titer of 1114. The immunoglobulins in the prepared antiserum were precipitated using saturated ammonium sulphate solution. Its concentration was adjusted to be 18mg/ml in normal saline then it was conjugated with horse radish peroxidase and evaluated through the application of double sandwich ELISA. It was successful to detect Pasteurella multocida antibodies in positive serum samples with strong positive reactions up to a dilution of 1:100 of the prepared conjugate.In the present study, polymerase chain reaction (PCR) using random primer (E-20) was used to characterize and identify strains included in this study. Strains included 4 vaccinal reference strains of Pasteurella multocida, CU strain and 4 field isolates of Pasteurella multocida isolated from diseased turkeys which were identified biochemically and serologically as A:1, A:3, A3x4 and D:11. The obtained results revealed that all strains were reacted positively and in different manner with the E20 primer except the 2 field isolates. The results of these reactions demonstrated in terms of bands of different molecular weight specific to each strain. This can be used as a base for characterization and differentiation of strains involved in the present study as the 2 field strains A:1 and A:3 react with primer. Mouse protection test was performed by vaccination of mice with local fowl cholera oil adjuvant vaccine then challenge with virulent field strains A:1, A:3, D:12 and untypable isolates. Results revealed that the local fowl cholera adjuvant vaccine could protect mice against virulent challenge with A:1, A:3 and D:12 field strains but it could not be protect mice against untypable isolates
显示更多 [+] 显示较少 [-]Some helminthes of the Great Egret (Egretta alba) in Saudi Arabia
2007
A. N. Al Khalaf
A. N. Al Khalaf helminthes , Egret , Egretta alba , Saudi ArabiaExamination of the alimentary tracts of 9 Great Egret (Egretta alba) found freshly died in their inland places around Al-Qassim area during migration season in September and October revealed infection by 6 species of helminths. The extracted parasites were include two cestode worms, three nematodes and one acanthocephala. They were identified as Uniciuna species, Choano-taenia, Subulura species, Contrac-aecum species, Syphacia species and Polymorphus species. None of any examined carcass appears free from infection. The rate of distribution of the parasite in the examined birds was varied between 66.6%, 11.1%, 44.4%, 44.4%, 66.6% and 2.2 % for the previous parasites respectively. The rate of Parasite burden for each species was moderate to low, as it was 3.4, 2.0, 2.65, 3.25, 5.16 and 4.5 from the previous parasites respectively. None of these parasites was published previously in Saudi Arabia as infect this type of Egret. Their morphological characters and their distribution were described in detail
显示更多 [+] 显示较少 [-]Bacteriological Quality of Mozzarella Cheese Sold in Tripoli Governorate
2007
A. M. Garbaj | H. T. Naas | F.T. Gammoudi | A. A. Moawad
Thirty samples of Mozzarella cheese (15 made traditionally from raw milk in Tripoli city (Libya) and other 15 imported samples sold in markets related to different brand names) were examined bacteriologically for their total bacterial count, psychrophilic count, coliform count (MPN/g), presumptive Staphylococcus aureus count, as well as enterococci count. Higher counts were found in locally manufactured Mozzarella cheese. Salmonellae were absent in all examined samples for both types, while Escherichia coli were isolated from 3 samples (20%) of locally made samples. According to the suggested Libyan Standards of such samples, most of examined locally manufactured Mozzarella cheese samples were found unacceptable.
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]Biochemical changes in lipid peroxidation and anti oxidative defense following lipoic acid administration in alloxan-induced diabetes in rats
2007
S. A. Abd El-Salam | M. R. Ragab | M. A. Kandeil | Eman T. Mohamed
The present study aimed to assess some biochemical changes of oxidative stress in alloxaninduced diabetic rats with administration of lipoic acid. The experiment was carried out on 96 male rats. The group I (32 rats) was left as control (normal non-diabetic). Sixty-four rats were injected subcutaneously with alloxan (120 mg / kg.b.wt.) for induction of diabetes. Then it was divided into two equal groups, group II (diabetic without administration of lipoic acid) and group III (diabetic with administration of lipoic acid). Blood samples were collected from 8 rats of each group for separation of clear serum at 1st, 2nd, 3rd and the 4th week after administration for determination of glucose. Fresh liver and brain tissue samples (0.2 g) were collected from sacrificed rats and homogenized in ten volumes of (ice-cold phosphate saline pH: 7), then kept at –20 ?C for assay of malondialdehyde, reduced glutathione and liver glycogen. The obtained data revealed that serum glucose level was significantly decreased in the 3rd group as compared with the diabetic one. Also there was a significant decrease of liver glycogen in the diabetic group as compared with the non-diabetic control group. Moreover, significant decrease of reduced glutathione in both liver and brain tissues in diabetic group as compared with control. Lipoic acid caused a significant elevation in liver reduced glutathione as compared with the diabetic group, but without effect on brain. There was a significant rise in malondialdehyde in liver and brain tissues of diabetic group as compared with control. On the other hand there was a significant decrease of malondialdehyde in liver and brain tissues of diabetic rats with lipoic acid as compared with diabetic rats throughout the experiment period. It could be concluded that significant increase of malondialdehyde together with the decrease of reduced glutathione in the diabetic group: indicated the oxidative stress of induced diabetes. Also the study revealed that lipoic acid exerted a powerful antioxidant effect and therefore the diabetics should be supplemented regularly with this vitamin.
显示更多 [+] 显示较少 [-]Intramammary antibiotics in dairy goats : withdrawal periods of three intramammary antibiotics compared to recommended withdrawal periods for cows
2007
J. Karzis | E.F. Donkin | I.M. Petzer
Intramammary antibiotics are registered and tested for use in dairy cattle. This study investigated withdrawal periods of three intramammary antibiotics (Curaclox LC [Norbrook Pharmacia AH]), Spectrazol Milking Cow (Schering-Plough Animal Health) and Rilexine 200 LC (Logos Agvet [Virbac]) in dairy goats and compared them to withdrawal periods recommended for use in cattle. Three trials were carried out in two different herds. The withdrawal periods for Curaclox LC in eight relatively low producing Saanen goats were 74.3 h (+ 19.21) measured by Thermo-Resistant Inhibitory Substances (TRIS), 90.0 h (+ 16.97) measured by colour dye, 99.4 h (+ 9.07) for cloxacillin measured by Parallux Beta Lactam Assay test (IDEXX distributors), and 92.6 h (+ 11.41) for ampicillin measured by Parallux. The withdrawal period for Curaclox LC recommended for use in cattle (72 h) was significantly shorter than the withdrawal periods as measured by colour dye (P < 0.001), Parallux testing for cloxacillin (P < 0.001) and ampicillin (P = 0.003). There was a significant difference in withdrawal periods as measured by TRIS (P = 0.009) and colour dye (P = 0.036). The mean withdrawal periods measured on 12 relatively high producing Saanen and Saanen-Toggenburg crossbreed dairy goats measured by TRIS, colour dye and Parallux for ampicillin and cloxacillin were, however, shorter at 42.0 h (+ 7.077), 64.5 h (+ 60.26), 77.3 h (+ 13.56) and 70.7 h (+ 12.65), respectively. These withdrawal periods for Curaclox LC were significantly longer than the withdrawal periods recommended for cattle as measured by TRIS (P < 0.001) and colour dye (P < 0.001). The combined withdrawal periods for Curaclox LC in the two trials as measured by TRIS, colour dye, Parallux testing for Cloxacillin and Ampicillin were 58.64h (+ 24.31), 75.8 h (+ 17.70), 87.0 h (+ 16.10) and 80.3 h (+ 16.23), respectively. The withdrawal period, when data of the two trials were combined, measured by TRIS (P < 0.001) was significantly longer than the withdrawal period recommended for use in cattle. The mean withdrawal period as measured by TRIS for Spectrazol Milking Cow for seven relatively low producing Saanen dairy goats was 95.3 h (+ 17.23). This was significantly (P < 0.001) longer than the withdrawal period recommended for use in cattle (60 h) for Spectrazol Milking Cow. The mean withdrawal period as measured by TRIS for Rilexine 200 LC for 20 relatively high producing Saanen and Saanen-Toggenburg crossbreed dairy goats was 36.9 h (+ 9.943) and was significantly (P < 0.001) shorter than the withdrawal period as recommended for use in cattle (96 h). There were also significant differences in all the one-sample t-tests between withdrawal periods for goats and recommended withdrawal periods for cattle without the 24 h safety margin.
显示更多 [+] 显示较少 [-]Red blood cell volume as a predictor of fatal reactions in cattle infected with <i>Theileria parva</i> Katete
2007
P. Fandamu | T. Marcotty | J.R.A. Brandt | L. Duchateau | N. Speybroeck | T.T. Dolan | D. Berkvens
A comparison of mean corpuscular volume (MCV) and packed cell volume (PCV) was made between cattle undergoing lethal and non-lethal reactions following experimental infections with the apicomplexan protozoa, Theileria parva Katete. This work confirmed that anaemia occurs in infected animals. However, the fall in PCV was steeper in lethal reactions compared to non-lethal reactions. Our results show that animals with initially lower MCV values are more prone to fatal reaction, despite having normal PCV profiles. The study also found that small red blood cells are more likely to be infected with T. parva. These findings suggest that animals with a higher proportion of small red blood cells in circulation will be more likely to succumb to T. parva infections. The potential for using MCV as a predictor of the outcome of infection challenge is discussed.
显示更多 [+] 显示较少 [-]Anti-inflammatory, antipyretic and analgesic effect of Achillea millefolium and Salix plants
2007
S. E. El-Sadek | A. A. M. El-Gendy | M.A. Tohamy | M. A. Abd El-Aa
The Anti-inflammatory, antipyretic and analgesic effect of Achillea millefolium and Salix were investigated in rats and mice. The extracts of Achillea millefolium exerted significant antiinflammatory, antipyretic and analgesic effects. Also potentiated the sleeping time of thiopental sodium in mice. The doses used were 10.375 and 20.75 (watery extract) and 9.5 and 19 mg/100 gm b.wt. (ethanolic extract). Salix produced the same effects at doses of 0.0825 and 0.165 (watery extract) and 0.0850 and 0.170 mg/100 gm b.wt. (ethanolic extract). The extracts of both plants have an anti-inflammatory, antipyretic and analgesic effect
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