Refinar búsqueda
Resultados 51-60 de 424
Seroprevalence survey of Chlamydophila abortus infection in breeding goats on commercial farms in the Otavi Veterinary District, northern Namibia Texto completo
2010
Samkange, Alaster(Ministry of Agriculture Directorate of Veterinary Services) | Katsande, Tendai C.(ARC Onderstepoort Veterinary Institute) | Tjipura-Zaire, Georgina(Central Veterinary Laboratory) | Crafford, Jan E.(University of Pretoria Department of Veterinary Tropical Diseases Faculty of Veterinary Science)
A total of 1076 sera from breeding goats were randomly collected from 24 different farms and tested with CHEKIT®-ELISA (IDEXX Laboratories B.V., 1 119 NE Schiphol-Rijk, Nederland) for antibodies against Chlamydophila abortus. The farms were divided into two categories of twelve farms each, based on their previous history of observed abortions over the previous 12 months: those with low (< 5%) levels of abortion and those with high (> 5%) levels of abortion. The farmers were also interviewed on their level of awareness about chlamydophilosis, its zoonotic importance and vaccination measures against the disease. The study detected overall seroprevalence levels of 25% for the farms and 8% for the individual animals (at 95% confidence). A total of six out of twenty-four farms (25%) had at least one positive breeding animal. Only five out of the twenty-four (20.8%) farmers interviewed were aware of chlamydophilosis and its zoonotic dangers. None of the 24 farmers interviewed practised any vaccination against chlamydophilosis. There was a significantly higher number of seropositive animals from farms with high levels of abortion, compared to those animals from farms with low levels of abortion (p = 0.0001). This study underscores the need for a higher level of farmer awareness and training on chlamydophilosis and its zoonotic dangers.
Mostrar más [+] Menos [-]The use of a rat model to evaluate the in vivo toxicity and wound healing activity of selected Combretum and Terminalia (Combretaceae) species extracts Texto completo
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.
Mostrar más [+] Menos [-]Distribution of capsular serotypes and virulence markers of Streptococcus suis isolated from pigs with polyserositis in Korea Texto completo
2010
Kim, Duyeol | Han, Kiwon | Oh, Yeonsu | Kim, Chung Hyun | Kang, Ikjae | Lee, Jeehoon | Gottschalk, Marcelo | Chae, Chanhee
The objective of this study was to determine the capsular serotypes and potential virulence factors of Streptococcus suis isolated from pigs with polyserositis. Among the 24 isolates evaluated, serotype 3 [7 (29%) of the isolates] and serotype 4 [5 (21%)] were the most common. The isolates were also studied for the presence of the genes mrp, epf, and sly, which encode muramidase-released protein (MRP), extracellular factor (EF), and suilysin (SLY), respectively. Of the 24 isolates, 8 carried mrp: 4 of serotype 3, 2 of serotype 2, and 2 of serotype 4. One mrp+ isolate (serotype 2) also carried the epf gene. All 24 isolates carried the sly gene. The serotype and genotype distribution greatly differed from that reported for isolates from pigs with other clinical manifestations of S. suis infection in other countries.
Mostrar más [+] Menos [-]Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes Texto completo
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.
Mostrar más [+] Menos [-]Non-O157 verotoxigenic Escherichia coli and beef: A Canadian perspective Texto completo
2010
Gill, Alexander | Gill, Colin O.
Verotoxigenic Escherichia coli (VTEC) are important foodborne pathogens in Canada. VTEC of the O157:H7 serogroup have been the focus of regulatory action and surveillance in both Canada and the USA, due to their role in a number of high profile outbreaks. However, there is increasing evidence that other VTEC serogroups cause a substantial proportion of human illness. This issue is of particular importance to the cattle industry due to the role of beef as a vehicle for VTEC transmission. In this review, the evidence for non-O157 VTEC as cause of human illness in Canada and the potential for Canadian beef and cattle to serve as a source of VTEC are presented. In addition, the available strategies for the control of VTEC in cattle and beef are discussed.
Mostrar más [+] Menos [-]A transducer for measuring force on surgical sutures Texto completo
2010
The objective of this study was to validate, both in vitro and in an ex vivo model, a technique for the measurement of forces exerted on surgical sutures. For this purpose, a stainless steel E-type buckle force transducer was designed and constructed. A strain gauge was mounted on the central beam of the transducer to measure transducer deformation. The transducer was tested and calibrated on a single strand of surgical suture during cyclic loading. Further validation was performed using a previously published cadaveric model of laryngoplasty in the horse. Linear regression of transducer output with actual force during calibration tests resulted in mean R2 values of 1.00, 0.99, and 0.99 for rising slope, falling slope, and overall slope, respectively. The R2 was not less than 0.96 across an average of 75 cycles per test. The difference between rising slope and falling slope was 4%. Over 45 846 samples, the predicted force from transducer output showed a mean error of 4%. In vitro validation produced an adjusted R2 of 0.99 when the force on the suture was regressed against translaryngeal pressure in a mixed-effects model. E-type buckle force transducers showed a highly linear output over a physiological force range when applied to surgical suture in vitro and in an ex vivo model of laryngoplasty. With appropriate calibration and short-term in vivo implantation, these transducers may advance our knowledge of the mechanisms of success and failure of techniques, such as laryngoplasty, that use structural suture implants.
Mostrar más [+] Menos [-]Effects of ketamine-xylazine intravenous bolus injection on cardiovascular function in rabbits Texto completo
2010
Baumgärtner, Christine | Bollerhey, Melanie | Ebner, Johanna | Laacke-Singer, Lien | Schuster, Tibor | Erhardt, Wolf
The direct effects of ketamine-xylazine (KET-XYL) on vascular function have not been investigated in rabbits. The short-term cardiovascular effects of intravenous (IV) KET-XYL bolus injection, therefore, should be investigated using vascular ultrasonography.In this prospective experimental study, KET-XYL anesthesia was induced IV in 9 female New Zealand White rabbits before 3 defined test bolus injections of KET-XYL were given IV. Before and for 10 min after each KET-XYL injection vascular and hemodynamic variables were recorded at the left common carotid artery (ACC) after the 1st injection, and at the abdominal aorta (AA) after the 2nd injection. Echocardiography was performed after the 3rd injection to investigate changes in cardiac parameters.Ketamine-xylazine IV caused a significant increase in vessel diameter at the ACC and AA. Average volumetric flow significantly decreased at the ACC and pulsatility index significantly decreased at the AA. Fractional shortening (FS) and heart rate significantly decreased, while mean arterial blood pressure initially increased.Bolus injections of KET-XYL IV produced a transient vasodilatation at the ACC and AA. Despite central vasodilatation, bradycardia, and decrease of FS and average volumetric flow (VFave), mean arterial blood pressure did not significantly decrease indicating well-preserved cardiovascular compensatory mechanism after the ratio and doses of KET-XYL IV bolus injections used in this study.
Mostrar más [+] Menos [-]Detection of residues of some heavy metals in fish fillets in Egyptian markets Texto completo
2010
R. H. Abdel-Dayem | H. M. Soltan | N. M. Marzouk
Fifteen samples of fish fillets were collected from different Egyptian markets to detect the residues of some heavy metals in them. The average weights of fish fillets samples were 250g. The samples were separately packed in polyethylene bag and sent to the laboratory for preparation and analysis. All equipment surfaces and utensils which used in this study were thoroughly cleaned with detergent, rinsed with water, dried and then rinsed with 2-propanol solution. The samples were stored at –2C prior to analysis. The mean levels of lead and cadmium in fish fillets collected from the Egyptian markets were 1.51 0.34 and 0.60 0.0.25 mg/kg; respectively. The concentration of lead in fish muscle were less than the permissible heavy metal limit in fish meat (2.0 mg kg) as stated by the World Health Organization, also these results were in line with the corresponding EU regulations. However the level of cadmium concentration was over than the heavy metal limits in fish meat (0.5 mg/kg) for the World Health Organization.
Mostrar más [+] Menos [-]Comparative studies on anti-avian sera conjugated with fluorescin isothiocyanate Texto completo
2010
M. H. Khodeir | Ghada M. El-Sadek | Elham A. El-Ibiary
Rabbit antisera were successfully prepared against chickens; turkey; ducks; geese; pigeons and quails as antispecies and conjugated with fluorescein isothiocyanate (FITC). The ability to use these antisera as homologous and heterologous antispecies was studied through the application of indirect fluorescent antibody technique (FAT) using specific antigens and antibodies of Newcastle; infectious bursal disease virus; duck plague virus; duck hepatitis virus; fowl cholera and pigeon paramyxo virus. The results showed that Titration of the prepared anti avian sera conjugated with FITC induced strong positive FAT reactions up to dilutions of 1:10000; 1:1000; 1: 100000; 1: 1000; 1: 100000 and 1:1000 for anti- chicken; anti-Turkey; ant-duck; ant-goose; anti-pigeon and antiquill sera respectively. It was found that homolgous species anti-sera showed strong positive FAT reaction (green apple fluorescing) scored as 4+ while hetrologous species anti-sera showed less degree of positive reactions ranged from 3+ to ± reaction showing that the usefulness of anti-sera as reagents in serological techniques is limited by the homogeneity and heterogeneity of such antisera. So, the present preparations could be used to low extent as heterologous anti-avian sera.
Mostrar más [+] Menos [-]Studies on Corynebacterium pseudotuberculosis, Staphylococcus aureus and Staphylococcus aureus subsp. anaerobius isolated from sheep skin abscesses in Beni Suef Governorate. Texto completo
2010
Samia I. Afifi
Clinical examination of 380 rearing sheep revealed that 30 animal were suffering from skin abscesses with an incidence of (7.89%). Bacteriological examination of 30 swabs from affected sheep revealed isolation of 30 isolates of C. pseudotuberculosis (48.39%) , 18 isolates of S. aureus (29.03%) and 14 isolates of S. aureus subsp. anaerobius (22.58).The isolated bacteria were identified morphologically and biochemically.The results of animal pathogenicity test showed that C. pseudotuberculosis isolates were 100% pathogenic to guinea pigs and 80% of S.aureus isolates were pathogenic to mice, while all isolates of S. aureus subsp. anaerobius were pathogenic to mice. The dead animals showed haemorrhage and symptoms of septicaemia, C. pseudotuberculosis, S.aureus and S. aureus subsp. anaerobius were reisolated from the dead animals. Antimicrobial sensitivity of C. pseudotuberculosis , S. aureus and S. aureus subsp. anaerobius isolates to some antimicrobial agents which usually used in farms showed that from 90% to 100% of C. pseudotuberculosis isolates were sensitive to erythromycin, amoxicillin, tetracycline ,streptomycin, ampicillin and rifampicin while S. aureus isolates (from 55% to 66%) were sensitive to rifampicin,tetracycline ,erythromycin and streptomycin, while S. aureus subsp. anaerobius isolates were moderately resistant to all used antimicrobial agents.
Mostrar más [+] Menos [-]