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Studies on the toxicity of an aqueous extract of the leaves of Abrus precatorius in rats
2007
A.A. Adedapo | O.A. Omoloye | O.G. Ohore
The toxic effects of an aqueous extract of Abrus precatorius were studied in 20 male white rats over a period of 18 days. The rats were divided into four groups of five rats per group. Those in Group A served as controls while the rats in Groups B, C and D were dosed per os with 400 mg/kg, 800 mg/kg and 1 600 mg/kg of the extract, respectively. Blood samples were collected for haematological and biochemical analysis and specimens of the liver, kidney and testes were taken for histopathological studies. The study showed that the extract of A. precatorius caused decreased levels of packed cell volume, haemoglobin concentration, red blood cell count, white blood cell count, mean corpuscular volume and mean corpuscular haemoglobin. The extract also resulted in increased levels of total serum protein, albumin, alanine amino transaminase, aspartate amino transferase, alkaline phosphatase and total bilirubin. Histologically, testicular degeneration characterized by decreased numbers of lining cells of the epithelium as well as reduction in sperm cells with presence of scattered Sertoli cells were noted. The study thus showed that aqueous extract of Abrus precatorius is toxic and caution should be exercised in its use for medicinal purpose.
Afficher plus [+] Moins [-]Some macromorphological studies on the ventricular musculature of the heart of the donkey
2007
S. A. Ragab | Y. R. Wally | F. M. Farag | M. A. N. M. Nazif
The present work was conducted on 25 hearts of healthy donkeys of both sexes. Three methods were adopted to clarify the musculature of the ventricles; nitric acid method, acetic acid method and flour paste method. The ventricular myocardium was arranged into three layers: superficial, middle and deep. The superficial layer consists of eleven bundles arranged longitudinally from the base to the apex of the heart. Moreover, a thin subepicardial layer separated it from the epicardium. The middle layer on the right ventricle was horizontally oriented, while on the left ventricle it was represented by three bands; (A), (B) and (C). The deep layer on the right ventricle was formed of two bands (A) and (B) while on the left ventricle consisted of a single band (C), in addition to some fibers derived from the superficial layer. Theintervrentricular septum was formed from fibers extended from the middle and deep layers. The papillary muscles were four in the right ventricle and two in the left one.
Afficher plus [+] Moins [-]Molecular characterization of Corynebacterium pseudotuberculosis isolated from sheep by random amplified polymorphic DNApolymerase chain reaction (RAPD-PCR)
2007
Azza S.A. Goda | Mona A. Mahmoud | Wafaa A. Osman | N.A. Ziada | I. M. Moussa
The phenogenetic and phylogenetic relationships among 7 identified strains of C.pseudotuberculosis isolated from sheep were checked by PCR specific primers demonstrated with random amplified polymorphic DNA – polymerase chain reaction (RAPD – PCR) by using five arbitrarily primers. C pseudotuberculosis isolates were distinguished according to the banding patterns of their amplified DNA on agarose gel. The variation can be used for diagnostic differentiation among C. pseudotuberculosis strains. Differences were observed in RAPD patterns between the 7 isolates and this may be due to the presence of novel serovars of this microorganism.
Afficher plus [+] Moins [-]Comparison between tuberculin test results and ELISA for diagnosis of bovine tuberculosis
2007
F. R. El-Seedy | Sohair S. Elyas | W.H. Hassan | E. A. Nasr
A total of 300 cross-bred dairy cattle in Beni-Suef and El-Fayoum Governorates were screened for bovine tuberculosis using single intradermal (SID) cervical tuberculin test. 18 out of 300 (6%) tested cattle were found tuberculin positive. Blood samples from the positive reactors were tested by ELISA. ELISA plates were coated by either bovine purified protein derivative (PPD) or short term culture filtrate (ST-CF) antigens. The test sensitivity was compared at different serum dilutions. At serum dilution of 1/40, all of the 18 tuberculin positive samples, (100%), were ELISA positive using both ST-CF and PPD antigens, but at 1/80 dilution, 13 (72.22%) and 12 (66.66%) samples; at 1/160, 11 (61.11%) and 11 (61.11%) and finally at 1/320, 10 (55.55%) and 9 (50%) were ELISA positive on using ST-CF and PPD as a coating antigens respectively
Afficher plus [+] Moins [-]A potential krimpsiekte vaccine
2007
C.J. Botha | J.E. Crafford | V.P. Butler Jr. | M.N. Stojanovic | L. Labuschagne
Krimpsiekte, a chronic form of cardiac glycoside poisoning, is an important plant-induced intoxication of small stock in South Africa. It is caused by cumulative, neurotoxic bufadienolides, such as cotyledoside. A cotyledoside-bovine serum albumin conjugate was synthesized to immunize animals. The efficacy of the cotyledoside-conjugate in inducing an immunological response was ascertained in rabbits (n = 4) and sheep (n = 4) by determining cotyledoside antibody titres with an ELISA using cotyledoside-hen ovalbumin as antigen. The formation of anticotyledoside antibodies was induced in both rabbits and sheep following immunization with the cotyledoside-protein conjugate. Protection provided by the vaccine was demonstrated by challenging sheep (n = 4) with repeated, daily doses of cotyledoside (0.015 mg / kg) administered intravenously, commencing 45 days after the initial vaccination. One control animal died on Day 3 of the challenge period and the other was severely affected after administration of the third cotyledoside dose. The immunized ewes (n = 2) remained clinically unaffected and the challenge was suspended following six daily injections. Vaccination as a means of preventing krimpsiekte seems to be quite feasible and deserves further investigation.
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 [-]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.
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 [-]Detection of Chlamydophila psittaci in chickens by complement fixation test and polymerase chain reaction
2007
Wafaa A. Osman | A. L. El-Naggar | Azza S. A. Gooda | Mona A. Mahmoud
This study was carried out on 68 randomly collected chickens located at Ras Sedr Research Station, Desert Research Center, 68 serum samples were examined serologically by complement fixation test (CFT). Twenty out of 68 (29.91%) had antibodies against Chlamydophila psittaci . Ten blood samples of the serologically positive cases were subjected to polymerase chain reaction (PCR) and showed positive results for Chlamydophila psittaci at 119 bp. Therefore PCR was found to be reliable, rapid, sensitive and specific technique for the detection Chlamydophila psittaci in birds. Serologically positive birds did not show any clinical symptoms of disease, but they were in contact with sheep and goat that showed previous abortion and were positive for C. abortus. It is recommended to avoid breeding of chickens with other animal species in the same yard because chickens become asymptomatic carrier with shedding of Chlamydophila psittaci in their feaces and respiratory discharges.
Afficher plus [+] Moins [-]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
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