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Effects of ketamine-xylazine intravenous bolus injection on cardiovascular function in rabbits
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.
Afficher plus [+] Moins [-]Assessment of 2 Salmonella enterica serovar Typhimurium-based vaccines against necrotic enteritis in reducing colonization of chickens by Salmonella serovars of different serogroups
2010
Jiang, Yanfen | Kulkarni, Raveendra R. | Parreira, Valeria R. | Poppe, Cornelius | Roland, Kenneth L. | Prescott, John F.
This study assessed the protective efficacy of oral vaccination with 2 experimental attenuated Salmonella Typhimurium-vectored vaccines for necrotic enteritis in protecting chickens against intestinal colonization by common serovars of Salmonella belonging to the 4 major serogroups affecting chickens. Birds were vaccinated orally with 1 × 108 colony-forming units (CFU) of 1 of the vaccine strains χ9241 and χ9352, which express a plasmid-encoded partial recombinant hypothetical protein gene (tHP) of Clostridium perfringens, at days 1 and 7 of age, and then were challenged at 14 d of age with 106 CFU of Salmonella serovars Anatum, Enteritidis, Heidelberg, Kentucky, or Typhimurium (representative serovars of serogroups B, C, D, and E). Birds were necropsied at 4 wk of age, and samples were collected to determine reduction in tissue and intestinal colonization. The chickens vaccinated with χ9241-tHP showed reduced colonization by Salmonella Enteritidis (serogroup D) and by Salmonella Heidelberg and Salmonella Typhimurium (serogroup B) compared with the control birds. No reduction in colonization was observed in the chickens vaccinated with χ9352-tHP. There was an association between the efficacy of these vaccine strains in protecting against necrotic enteritis, assessed on an earlier occasion, and their efficacy in protecting against Salmonella colonization. Thus, the choice of an attenuated Salmonella Typhimurium vaccine vector for delivery of heterologous antigens to chickens should be based partly on the vaccine’s value in protecting against colonization by serovars within serogroups B and D. Such vectors would have the additional benefit of reducing colonization of important Salmonella serovars.
Afficher plus [+] Moins [-]Prediction of serum ionized calcium concentration by serum total calcium measurement in cats
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.
Afficher plus [+] Moins [-]Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke
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.
Afficher plus [+] Moins [-]Influence of water quality on fish productivity
2010
M. A. El Bably | H. H. Emeash | Asmaa N. Mohamed | Nahla R.
The physical, chemical and bacteriological parameters of water in fish ponds were investigated with a view to optimize the conditions for fish productivity by using three private fish farms with different water supplies. Water and fish samples were collected equally from each pond over a period of 17 months. Water temp., Dissolved oxygen (DO), pH, Ammonia, Nitrite, Nitrate, and bacterial count were determined. The average values of bacterial, parasitic, survival and growth rates of fish were also assessed. Results revealed that pond water in farm (III) had the highest averages of temperature nitrite, nitrate 31.8±1.5, 8.18± 0.9, 0.41 ± 0.06 , 3.79 ± 0.6 resp., with the least content of DO 3.6 ± 0.7 followed by farm (II),which had also the highest mean values of NH3 - N, total coliform and fecal coliforms were 3.15±0.65, 59.0 & 18.5 followed by ponds of farm (III), while, the lowest averages of estimated parameters were recorded in farm (I).Correspondingly, fish samples of farm (III) showed the highest level of total bacterial, coliform, fecal coliform count and parasitic infestation; were 42.5±5.4, 29.6±3.6 , 11.3±3.1 and 31.15% respectively, followed by fish of farm(II) 29.75±3.5, 11.5±3.3, 7.4±1.1 and 10.8 % respectively, Meanwhile, fish in farm (I) showed the lowest value of both bacterial contents with no parasitic infestation which explain the highest percentages of daily weight gain & survival rates 35.2±4.4 gm. & 97.0 ±1.6 % respectively. Throughout study period compared with those in farms (III & II) respectively, resulting from poor water quality & parasitic infestation which acts as stressors affecting fish health and productivity. Therefore, fish productivity can be enhanced if the water quality in the ponds were maintained at optimum levels.
Afficher plus [+] Moins [-]Comparison between molecular and classical techniques for identification of Mycoplasma species isolated from mastitic ruminants
2010
W. H. Hassan | Mona A. El-Shabrawy | E. G. Sadek
A total of 165 cows, 19 buffaloes, 192 sheep and 118 goats were examined for detection of Mycoplasma mastitis. The results revealed that 114 (69.59%) and 6 (31.57%) were clinically mastitic cows and buffaloes respectively while 51 (30.9%) and 13 (68.42%) were apparently healthy cows and buffaloes respectively. On examining the apparently healthy cows and buffaloes, 67 (32.84%) and 18 (34.61%) were subclinically mastitic cows and buffaloes respectively. Mycoplasmas were isolated in percentages of 8.9%, 5.5% from subclinically mastitic cows and buffaloes respectively and in percentages of 12.97%, 12.5% from clinically mastitic cows and buffaloes respectively. M. bovis was isolated from 8 (32%) and M. bovigenitalium from 7 (28%) and 10 (40%) unidentified Mycoplasma. Isolation of Mycoplasma from udder tissue in cows and buffaloes were in a percentage of 28.5% in cows while no Mycoplasma isolates were obtained from buffaloes' udder tissues. Application of PCR technique on these isolates and some of the negative samples was positive 100%. On the other hand, the results revealed that 82 of 192 (42.7%) and 43 of 118 (36.44) of the examined sheep and goats respectively were clinically mastitic. Isolation of Mycoplasma was from 11 (13.41%) and 17 (39.53%) of the examined sheep and goat respectively. Identification of these isolates revealed 8 (29%) M. agalactiae isolates and 20 (71%) unidentified Mycoplasma spp. Application of PCR technique on traditionally identified M. agalactiae isolates revealed negative results on using M. agalactiae specific primer while positive results were obtained for the same 8 isolates (100%) on using M. bovis specific primer.
Afficher plus [+] Moins [-]Epidemiological studies on Listeriosis in sheep
2010
E. E. Younis | A. A El-Sawalhy | Soumaya E. A. | M. A. A. El-Beskawy
This study was carried out in El-Dakahilia governorate on six flocks at different areas 2448 sheep located with varied ages and with history of nervous manifestation. The Prevalence of nervous manifestations was 4.9% (105 /2448). The case fatality rate and mortality rate were 77.14 % and 3.3 % respectively. The percent of Listeria monocytogenes was 26.66% (8/30). Examination of CSF of diseased and control healthy sheep revealed significance elevation of total cell count, total protein and creatinine cytokinase of diseased than control sheep.
Afficher plus [+] Moins [-]Impairment of female Oreochromis niloticus fecundity exposed to Butachlor herbicide
2010
Manal A. A. Essa | M. S. Marzouk | Nashwa S. Elias | Maysa H. Shaker | Ghada M. A. Mohamed
Female Oreochromis niloticus were exposed to 1/10 LC50 (0.21ppm) of butachlor herbicide for 6 weeks. Weekly specimens were taken for fecundity estimation. Also hormonal and enzymatic levels were determined in addition histopathological alterations in ovaries and liver were detected. Butachlor exerted drastic effects on absolute and relative fecundity. Sex hormones (testosterone "T" and estradiol "E2") dropped significantly. The high significantly decline in Total Ripen Egg Number was assisted by the coagulative necrosis and oocytic atrasia in ovaries. In addition, thrombus formation and hepatoadenocarcinoma were pronounced in the liver and resulted in the significant drop in ALT and total protein levels. So, it is recommended to apply the biological control of pests in substitution to herbicids in rice fields.
Afficher plus [+] Moins [-]The situation of poultry industry and related veterinary service in republic of Yemen, 2007
2010
G. A. Zohair
The purpose of the assignment is to provide technical assistance to support the preparation /strengthening of the currently drafted Integrated National Planning for disease prevention, require-ment from poultry products and required improvements for future. The obtained data here were col-lected from site visits and interviews with project owner as well as official documents and reports.
Afficher plus [+] Moins [-]Potentials of human exposure to Listeria spp. from dairy cattle
2010
A. E. Abdel-Ghany | M. A. Ibrahim
This study was performed in the period February 2009 through January 2010 to determine the role of dairy cattle in transmitting listeriosis to man in Beni-Suef Governorate, Egypt. Individual milk samples and rectal swabs were gathered from 175 dairy cows (125 clinically diseased and 50 apparently healthy). A total of 75 kariesh cheese and 150 dairy shop milk samples were randomly collected from the same localities where the examined cattle were reared. Stool and blood samples were taken from 125 humans comprising 75 individuals residing in close contact with the examined cows and 50 feverish inpatients. The occurrence of Listeria spp. in the examined dairy cattle revealed that 1.14 % of individual milk samples harboured Listeria spp.; L. innocua (0.57 %) and L. seeligeri (0.57 %). None of rectal swabs revealed a positive result. L. monocytogenes could not be recovered from any of the examined cattle samples. Examination of kariesh cheese demonstrated a positive result to L. innocua (1.33 %). Concerning dairy shop milk examined, 5.33 % was Listeria spp.-positive; they were identified as L.monocytogenes (2.67 %), L. innocua (1.33 %) and L.seeligeri (1.33 %). Examination of humans revealed a positive result for L. welshimeri in a stool sample (0.8 %) taken from an apparently healthy woman while all the examined blood sampleswere Listeria-negative. It was concluded that listeriosis in Beni-Suef Governorate appears to be ofsporadic nature and that the potential of human exposure to Listeria spp. and L. monocytogenes from dairy cattle is more likely to exist in dairy shop milk rather than being related to the animal itself.
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