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Bovine Ephemeral Fever: Pathological and Immunohistochemical Studies
2010
K. A. El-Nesr | E. A. Mahdy | M. B. El-Begaway
A natural outbreak of Bovine Ephemeral Fever in Egypt during the summer of 2006 had been observed. In Beni Suef province, out of 70 cattle naturally infected with bovine ephemeral fever virus, three fattening calves suffered from subcutaneous emphysema died and were subjected to post-mortem examination. The findings revealed severe subcutaneous emphysema, interstitial and pulmonary emphysema. The serous membranes were thick, opaque and emphysematous. Microscopically, interstitial and pulmonary emphysema was prominent in most lobes of the examined lungs accompanied with pulmonary oedema and focal leucocytic aggregations in some areas. Angiopathy was demonstrated in all cases. The bronchial and mediastinal lymph nodes showed congestion and hemorrhages. Immunohistochemically, specific reaction for Bovine Ephemeral Fever virus was demonstrated in the lung and lymph nodes of the three cases; the pathogenesis of the disease was discussed.
Afficher plus [+] Moins [-]Antimicrobial activity of some cephalosporins with special reference to their effects on body weight and immune response to Newcastle disease vaccine in fayoumy chicks
2010
I. A. Radwan | Abeer M. Radi
The susceptibility of the most common bacterial pathogens, namely E. coli, P. mirabilis and Ps. aeroginosa which were isolated from egg incubators and yolk sacs of randomly selected one day old Fayoumy chicks to three selected cephalosporins (cephradine, ceftiofur and cefquinome) were studied. The minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) of the tested drugs and the effect of these antibiotics on the body weight gain, mortality and immune response against Newcastle disease (ND) vaccine of the same bread of chicks were also estimated. The tested organisms were sensitive to ceftiofur and cefquinome whereas E.coli and ps. aeroginosa were found to be resistant to cephradine. The results showed that mortalities were higher in control and cephradine treated groups, while it was lower in the ceftiofur and cefquinome treated groups. On the other hand, the lowest mean body weight was recorded in control group (155.7±6.55 gm) followed by ceftiofur treated group (162.5±2.06 gm) and the highest mean body weight was recorded in cefquinome treated group (183.5±1.66 gm, p < 0.01) at 30 days of age. The study revealed that the tested antibiotics not exert any immune suppressive effect against (ND) vaccine.
Afficher plus [+] Moins [-]Some studies on Corynebacterium pseudotuberculosis causing Oedematous Skin Disease in Egyptian buffaloes
2010
Magda F. Essa
Out of 63 bacteriologically examined sanguineous fluids samples which were collected from Oedematous Skin Disease (O.S.D.) lesions, 37 isolates of C. pseudotuberculosis (C.p.) were recovered. The sensitivity tests revealed that isolates were highly sensitive to trimethoprim + sulphamethoxazole, amoxycillin, gentamicin and enrofloxacin. Diphtheria toxin (DT) produced by C. pseudotuberculosis of buffalo was determined by using the double immunodiffusion technique, it was applied on concentrated exotoxins which was prepared from C.p. isolates against Diphtheria toxin antiserum, its results were 15 (40.54%) positive and 22 (59.46) %) negative to presence of DT. Virulence of isolates having only phospholipase D ( PLD) or both PLD and DT was assayed by S/C inoculation of exotoxines prepared from isolates in guinea pigs, 15(40.54%) guinea pigs died within 18 hours while 22 (59.46%) guinea pigs died during 48 hours. An important point in this investigation that there have been very rare previous reports describing the production of DT by local isolates of C. pseudotuberculosis of buffalo.
Afficher plus [+] Moins [-]Bacteriological hazards in camel's meat products
2010
F. A. Khalafalla | Zienab M. Niazi | Dalia Y. Mohamed
A total of one hundred meat products samples; 20 each of camel's minced meat, burger, rice kofta, frankfurter and luncheon were collected from different supermarkets at Cairo and Giza Cities. All samples were exposed to bacteriological examination and showed that the mean values of aerobic plate count, psychrophiles, coli forms, fecal coli forms, S. aureus, and B. cereus in examined camel's minced meat, burger and rice kofta were higher than luncheon and frankfurter. E. coli, Salmonellae, S. aureus and B. cereus, L. monocytogenes were isolated from examined camel's meat products by different percent. The public health significance of the isolated microorganisms as well as suggestions for improving the quality of the camel meat products were discussed.
Afficher plus [+] Moins [-]Efficacy of living attenuated Salmonella typhimurium vaccine in poultry
2010
Hanan M. Ibrahim | Zeinab M. Souror | N.A. Sherif | M. M. Lotfy | Elham A. El Ebiary | M. A. Makharita
The main goal of this study was to evaluate the protective efficacy of living attenuated Salmonella Typhimurium (S. Typhimurium) vaccine in poultry and to evaluate its use in control of salmonella infection in chickens. Oral vaccination of chickens within 36 hours after hatching and after 6 weeks from the first dose induced a strong humoral immune response as measured by ELISA. Challenge test was done with virulent strain of S. Typhimurium. Shedding of S. Typhimurium was detected during the first day, but after 14 days, salmonella could not be detected in the internal organs of vaccinated chickens compared with the non-vaccinated challenged chickens.
Afficher plus [+] Moins [-]Quality assurance of yoghurt during processing
2010
Saadia H. H. El- Shinawy | A. M. El Kholy | M. M. A. Zeinhom
he present study was carried out to determine the critical points during processing of yoghurt, through examination of Acidity % and Storch's test to detect the efficiency of heat treated milk samples and Microbiological examination of samples collected weekly over a period of 7 months for TCC, Thermoduric, Total coliform, Faecal coliform, E. coli, Enterococci, S. aureus, Yersinia enterocolitica and Total yeast and mould counts. A total of 100 samples of raw milk, heat treated milk, inoculated milk and yoghurt (25 of each) in addition to 75 samples from worker’s hands, plastic packages and mixing vat (25 of each) were collected under strict hygienic conditions, also twenty five samples of yoghurt at the end of the expire date were collected and examined microbiologically. The obtained results concluded that the major sources of yoghurt contamination were raw milk, improperly cleaned and sanitized worker’s hands as well as the added starter culture. Finally, the public health and economic importance of the isolated organisms were mentioned.
Afficher plus [+] Moins [-]Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes
2010
Parraguez, Victor H. | Atlagich, Miljenko A. | Urguieta, Bessie | Galleguillos, Marco | Reyes, Monica De los | Kooyman, David L. | Araneda, Silvia | Raggi, Luis A.
Fetal weight and the placenta of sheep at high altitude (HA) are affected by hypoxia. Placental changes (an increase in placental size and vascularization) are greater in ewes from populations that have lived for several generations at HA than in those exposed during just 1 gestation. This study investigated placental expression of vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS), 2 molecules involved in placental angiogenesis that could be upregulated by hypoxia. Two groups of ewes were maintained at HA (3589 m) during pregnancy: HA-native ewes (group HH) and ewes native to lowlands but moved to HA immediately after the diagnosis of pregnancy (group LH). A control group (LL) was kept at sea level. Near term, placentomes were removed, weighed, and processed for immunohistochemical detection of VEGF and eNOS, as well as for vascular area measurement. Placental weight was significantly higher in the HH group than in the LH and LL groups; between the latter 2 groups there was no significant difference. The placental area occupied by vasculature was significantly greater in both the HA groups than in the LH group; the number of placentomes was greatest in the LL group. The density of VEGF and eNOS in the placentome tissue was significantly greater in both HA groups than in the LL group. Although the density of VEGF was significantly lower in the HH group than in the LH group, no differences were observed in eNOS density between the HH and LH animals. These results demonstrate that chronic hypoxia upregulates the expression of placental VEGF and eNOS, suggesting an important role of these molecules in the placental response to HA hypoxia. In addition, an attenuated response to hypoxia in VEGF synthesis may be part of the long-term process of adaptation to HA.
Afficher plus [+] Moins [-]Sensory nerve conduction and nociception in the equine lower forelimb during perineural bupivacaine infusion along the palmar nerves
2010
The purpose of this investigation was to study lateral palmar nerve (LPN) and medial palmar nerve (MPN) morphology and determine nociception and sensory nerve conduction velocity (SNCV) following placement of continuous peripheral nerve block (CPNB) catheters along LPN and MPN with subsequent bupivacaine (BUP) infusion. Myelinated nerve fiber distribution in LPN and MPN was examined after harvesting nerve specimens in 3 anesthetized horses and processing them for morphometric analysis. In 5 sedated horses, CPNB catheters were placed along each PN in both forelimbs. Horses then received in one forelimb 3 mL 0.125% BUP containing epinephrine 1:200 000 and 0.04% NaHCO3 per catheter site followed by 2 mL/h infusion over a 6-day period, while in the other forelimb equal amounts of saline (SAL) solution were administered. The hoof withdrawal response (HWR) threshold during pressure loading of the area above the dorsal coronary band was determined daily in both forelimbs. On day 6 SNCV was measured under general anesthesia of horses in each limb’s LPN and MPN to detect nerve injury, followed by CPNB catheter removal. The SNCV was also recorded in 2 anesthetized non-instrumented horses (sham controls). In both LPN and MPN myelinated fiber distributions were bimodal. The fraction of large fibers (>7 μm) was greater in the MPN than LPN (P < 0.05). Presence of CPNB catheters and SAL administration did neither affect measured HWR thresholds nor SNCVs, whereas BUP infusion suppressed HWRs. In conclusion, CPNB with 0.125% BUP provides pronounced analgesia by inhibiting sensory nerve conduction in the distal equine forelimb.
Afficher plus [+] Moins [-]Characteristics of the molecular diversity of the outer membrane protein A gene of Haemophilus parasuis
2010
The molecular diversity of the gene encoding the outer membrane protein A (OmpA) of Haemophilus parasuis has been unclear. In this study, the structural characteristics, sequence types, and genetic diversity of ompA were investigated in 15 H. parasuis reference strains of different serovars and 20 field isolates. Three nucleotide lengths of the complete open reading frame (ORF) of ompA were found: 1098 base pairs (bp), 1104 bp, and 1110 bp. The OmpA contained 4 hypervariable domains, mainly encoding the 4 putative surface-exposed loops, which makes it a potential molecular marker for genotyping. Western blot analysis showed that the recombinant OmpAs of serovars 4 and 5 could cross-react with antiserum to all 15 serovars. Hence, although ompA of H. parasuis exhibited high variation among serovars, this variation did not seem to affect the strong antigenic characteristics of OmpA.
Afficher plus [+] Moins [-]The use of a rat model to evaluate the in vivo toxicity and wound healing activity of selected Combretum and Terminalia (Combretaceae) species extracts
2010
Masoko, Peter(University of Pretoria Department of Paraclinical Sciences Phytomedicine Programme) | Picard, Jackie(University of Pretoria Department of Veterinary Tropical Diseases , Faculty of Veterinary Science) | Eloff, Jacobus N.(University of Pretoria Department of Paraclinical Sciences Phytomedicine Programme)
Wound healing is a fundamental response to tissue injury and several natural products have been shown to accelerate the healing process. The present study was undertaken to determine the safety and efficacy of the topical treatment of acetone leaf extracts of Combretum imberbe, Combretum nelsonii, Combretum albopuntactum and Terminaliasericea based on their in vitro antimicrobial activity. Four circular full-thickness skin wounds were made on the backs of eight anaesthetised Wistar rats using aseptic techniques. The treatments were administrated topically using 10% and 20% concentrations of each extract in aqueous cream in separate treatments. Indications of erythema, exudate, crust formation, swelling and ulceration were used to determine the wound healing process. All of the wounds closed completely within 17 days. Throughout the experiment, a subcutaneous probe was used to determine that the body temperature and body weight of the rats were within the normal range. C. imberbe and C. nelsonii extracts accelerated wound healing, but there was no significant difference in wound contraction using 10% and 20% concentrations of the extracts in cream. The results also showed the potential usefulness of this model to measure accelerating wound healing. The extracts could perhaps overcome defects associated with healing failure in chronic wounds and prevent secondary bacterial and fungal infections.
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