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EVALUATION OF THE IMMUNE RESPONSES INDUCED BY EXPERIMENTAL INFECTION OF (BALB/c) MICE WITH SALMONELLA HADAR Полный текст
2010
Afaf Abdul Rahman Yousif | Maan M. Neima AL-Naqeeb
The present study bases on evaluate the immune responses due to experimental infection of (BALB/c) mice by Salmonella hadar . The experiment was carried out on eighty mice of both genders with age range (6 – 8) weeks old, the mice were divided randomly into three groups (group A:- contain 20 mice were administrated orally with infectious dose (1.5×107C.F.Uml) ,group B:- contain 40 mice were administrated orally with LD50dose (1.5×109 C.F.Uml) and groupC:- contain 20 mice which inoculated orally with 1 ml of PBS (pH=7.2) and consider as control group). The study has noticed that the experimentally infected mice are able to induce humoral immune response which represented by producing antibody against Salmonella hadar and this production was elevated after two weeks of administration and reach the peak after four weeks post infection then decline sharply after passage of six weeks post infection in both groups (A and B) but the titration of the antibodies in group B was higher on that recorded in group A. It is obvious that S. hadar is able to induce cellular immune response during experimental infection with infectious dose and LD50 dose and the results of delayed type hypersensitivity have showed increases in the thickness of the right footpads of the mice of both groups (A and B) and the highest mean of the thickness was after 24 hours post immunization. Finally, we concluded that Salmonella hadar in infected the host was able to induce both humoral and cellular immune responses and these responses are dose dependent.
Показать больше [+] Меньше [-]Seroprevalence survey of <i>Chlamydophila abortus</i> infection in breeding goats on commercial farms in the Otavi Veterinary District, northern Namibia Полный текст
2010
Alaster Samkange | Tendai C. Katsande | Georgina Tjipura-Zaire | Jan E. Crafford
A total of 1 076 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 twentyfour 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.
Показать больше [+] Меньше [-]Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke Полный текст
2010
Etheresia Pretorius | Ursula B. Windberger | Hester M. Oberholzer | Roland E. Auer
Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke Полный текст
2010
Etheresia Pretorius | Ursula B. Windberger | Hester M. Oberholzer | Roland E. Auer
A cerebrovascular accident or stroke is a rare condition in dogs, but previous studies suggest that it is now increasingly being recognised. Platelets and fibrin networks are involved in haemostasis,which is disrupted during a thrombotic event. In this study we investigate the ultrastructure of the fibrin networks of a dog that had suffered ischaemic stroke, following suspected thromboembolism from clots that became dislodged during catheter maintenance (flushing with heparinised saline) 2 days after carotid artery catheter insertion. Fibrin networks of blood samples that were collected immediately after the stroke, 15 min after treatment with streptokinase and 24 h after treatment, were studied. The results were compared to those of two control dogs. During a stroke, fibrin morphology changes to form a thick, matted layer.Post-treatment ultrastructure shows that the fibrin morphology returns to that comparable to controls. Our results show that during thrombotic risk, fibrin network morphology changes visibly and reduces the fibrinolytic activity of the coagulation system.
Показать больше [+] Меньше [-]Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke Полный текст
2010
Pretorius, Etheresia(University of Pretoria Department of Anatomy Faculty of Health Sciences) | Windberger, Ursula B.(Medical University Vienna Center for Biomedical Research) | Oberholzer, Hester M.(University of Pretoria Department of Anatomy Faculty of Health Sciences) | Auer, Roland E. J.(University of Pretoria University of Pretoria Biomedical Research Centre)
A cerebrovascular accident or stroke is a rare condition in dogs, but previous studies suggest that it is now increasingly being recognised. Platelets and fibrin networks are involved in haemostasis, which is disrupted during a thrombotic event. In this study we investigate the ultrastructure of the fibrin networks of a dog that had suffered ischaemic stroke, following suspected thrombo-embolism from clots that became dislodged during catheter maintenance (flushing with heparinised saline) 2 days after carotid artery catheter insertion. Fibrin networks of blood samples that were collected immediately after the stroke, 15 min after treatment with streptokinase and 24 h after treatment, were studied. The results were compared to those of two control dogs. During a stroke, fibrin morphology changes to form a thick, matted layer. Post-treatment ultrastructure shows that the fibrin morphology returns to that comparable to controls. Our results show that during thrombotic risk, fibrin network morphology changes visibly and reduces the fibrinolytic activity of the coagulation system.
Показать больше [+] Меньше [-]Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes Полный текст
2010
Parraguez, Victor H. | Atlagich, Miljenko A. | Urguieta, Bessie | Galleguillos, Marco | Reyes, Monica De los | Kooyman, David L. | Araneda, Silvia | Raggi, Luis A.
Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes Полный текст
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.
Показать больше [+] Меньше [-]Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes Полный текст
2010
Parraguez Gamboa, Víctor | Miljenko, Atlagich | Urquieta, Bessie | Galleguillos, Marco | Reyes Solovera, Mónica de los | Kooyman, David L. | Araneda, Silvia | Raggi Saini, Luis
Artículo de Publicación ISI | 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. | The authors thank Gabino Llusco and Enrique Perez for assistance with animal management and care. This study was funded by grants ENL 06/2 (from Direction of Research and Development, DID, University of Chile) and FONDECYT 1070405 (from National Agency for Scientific Research, CONICYT).
Показать больше [+] Меньше [-]Effect of Plocamium cartilagineum aegypticus on Boophilus annulatus Полный текст
2010
Rania A. Abd El-Wahab
Halogenated monoterpenes isolated from the red alga Plocamium cartilagineum aegypticus , proved their efficacy as acaricide. Both of Violacene and Mertensene, were adulticides with LC50's, 340.56 ppm and 759.23ppm, respectively, against the cattle tick; Boophilus annulatus adult females. Moreover, they can be used as ovicides. Violacene and Mertensene caused reduction in the hatchability by 96.77% and 95% respectively. Clinico-pathological studies were carried out and showed that Plocamium extract is safe to the host and none-target animals.
Показать больше [+] Меньше [-]A clinical field trial to evaluate the efficacy of vaccination in controlling Salmonella infection and the association of Salmonella-shedding and weight gain in pigs Полный текст
2010
A clinical field trial was performed to determine the effectiveness of an autogenous Salmonella Typhimurium bacterin compared with a commercial live S. Choleraesuis vaccine in pigs. The association between Salmonella shedding and weight gain was also investigated. Nine cohorts of weaned pigs, (330 to 350 pigs per cohort), were randomly assigned to 1 of 3 treatment groups (injection with S. Typhimurium bacterin, vaccination via water with S. Choleraesuis vaccine, or a control group receiving no vaccine). In each cohort, the average daily gain was calculated for a selected pen throughout the production stage. Pen (pooled) fecal samples were collected bi-weekly and cultured. The odds of Salmonella shedding in both vaccinated groups was higher than in the control group (P < 0.05). The prevalence of Salmonella shedding declined overall as pigs aged (P = 0.04). However, the control pigs showed the smallest decrease in Salmonella shedding over the entire production stage, while prevalence of Salmonella shedding in the vaccinated groups decreased twice as much as the control group over the entire production stage. Salmonella Typhimurium var. Copenhagen DT104, S. Cerro, and S. Agona, which had been isolated on the study farm previously, were recovered from pigs in this study. Shedding of S. Typhimurium var. Copenhagen decreased over time in both vaccine treatment groups. On the other hand, S. Cerro shedding rate was lower in the control pigs compared with vaccinated pigs and S. Agona could be recovered only from the samples collected from S. Choleraesuis vaccinated pigs. The pigs from pens with a higher Salmonella recovery rate experienced slower growth compared with pigs from pens where Salmonella was not isolated. This latter finding indicates that there might be an economic incentive for producers to try to control endemic salmonellosis if effective programs could be developed.
Показать больше [+] Меньше [-]Prediction of serum ionized calcium concentration by serum total calcium measurement in cats Полный текст
2010
Schenck, Patricia A. | Chew, Dennis J.
Feline serum samples (n = 434) were classified as hypercalcemic, normocalcemic, or hypocalcemic based on both total calcium (tCa) and ionized calcium (iCa) concentrations. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive diagnostic likelihood ratio (PDLR), and negative diagnostic likelihood ratio (NDLR) were calculated for prediction of hypercalcemia and hypocalcemia in all samples, in hypoalbuminemic cats, and in those with chronic renal failure (CRF) as compared with cats that had other conditions. Diagnostic discordance in prediction of iCa using tCa was 40%. Sensitivity of tCa in prediction of ionized hypercalcemia was low and specificity was high. The PDLR for prediction of ionized hypercalcemia or hypocalcemia was low in all cats, especially in those with CRF. Due to the high level of diagnostic discordance, tCa should not be used to predict iCa concentration. Concentration of iCa should be measured directly when accurate assessment of calcium status is needed.
Показать больше [+] Меньше [-]Non-O157 verotoxigenic Escherichia coli and beef: A Canadian perspective Полный текст
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.
Показать больше [+] Меньше [-]Prion genotypes of scrapie-infected Canadian sheep 1998–2008 Полный текст
2010
Harrington, Noel P. | O'Rourke, Katherine I. | Feng, Yuqin | Rendulich, Jasmine | DiFruscio, Cathleen | Balachandran, Aru
This report describes the genetics of the prion protein gene (PRNP) at codons 136, 154, and 171 for sheep diagnosed with naturally acquired classical scrapie in Canada between 1998 and 2008. Genotyping analysis was performed on 249 sheep with confirmed classical scrapie infection representing 98 flocks from 6 provinces. A further case-control analysis of 3 of these flocks compared the genotypes between infected sheep (n = 72) and those of their healthy flockmates (n = 1990). The incidence of classical scrapie in the Canadian sheep population was highly associated with the ARQ haplotype (91.8%) and the ARQ/ARQ genotype (91.6%). In addition, the ARQ haplotype was found at significantly higher frequency in scrapie-infected sheep when compared with their healthy flockmates. Comparison with other published data suggests that the scrapie risk of PRNP genotypes differs between Canada and countries where the VRQ allele is associated with the highest susceptibility to infection.
Показать больше [+] Меньше [-]Anti-obesity effects of onion juice in high fat diet-induced obese rats
2010
Kang, W.Y., Jeju National University, Jeju, Republic of Korea | Kim, M.Y., Jeju National University, Jeju, Republic of Korea | Jin, J.Y., Jeju National University, Jeju, Republic of Korea | Yang, H.K., Jeju National University, Jeju, Republic of Korea | Hong, H.J., Jeju National University, Jeju, Republic of Korea | Kim, D.G., Jeju National University, Jeju, Republic of Korea | Han, C.H., Jeju National University, Jeju, Republic of Korea | Lee, Y.J., Jeju National University, Jeju, Republic of Korea
This study investigated the effects of onion juice on the serum lipid components and blood pressure in obese rats fed high fat diets. Thirty-nine of Sprague-Dawley rats were divided into six groups, and were treated for 8 weeks: (1) normal diet (ND); (2) high fat diet (HFD); (3) HFD for first 4 weeks and high fat diet with 40% onion juice for the last 4weeks (H-H+O); (4) HFD with 40% onion juice for 8 weeks (H+O); (5) HFD for first 4 weeks and ND for the last 4 weeks (H-N); (6) HFD for first 4 weeks and ND with 40% onion juice for the last 4 weeks (H-N+O). The rates of increasing body weight were reduced in H+O and H-H+O groups compared with HFD group. The levels of triglyceride, low density lipoprotein-cholesterol and total cholesterol in blood serum were significantly decreased in the H+O and H-H+O groups compared with the HFD group. Administration of onion reduced the size of adipocyte, steatosis, and serum hyperlipidemia in obese rats fed HFD. Moreover, the antihypertensive effects of onion were observed in obesity rat fed HFD. Overall results suggest that onion reduces the serum lipid components and improves hypertension in obese rat fed HFD.
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