Affiner votre recherche
Résultats 271-280 de 463
Effects of syringe type and storage conditions on results of equine blood gas and acid-base analysis
2012
Kennedy, Sarah A. | Constable, Peter D. | Şen, İsmail | Couetil, Laurent
Objective: To determine effects of syringe type and storage conditions on blood gas and acid-base values for equine blood samples. Sample: Blood samples obtained from 8 healthy horses. Procedures: Heparinized jugular venous blood was equilibrated via a tonometer at 37°C with 12% O2 and 5% CO2. Aliquots (3 mL) of tonometer-equilibrated blood were collected in random order by use of a glass syringe (GS), general-purpose polypropylene syringe (GPPS), or polypropylene syringe designed for blood gas analysis (PSBGA) and stored in ice water (0°C) or at room temperature (22°C) for 0, 5, 15, 30, 60, or 120 minutes. Blood pH was measured, and blood gas analysis was performed; data were analyzed by use of multivariable regression analysis. Results: Blood Po2 remained constant for the reference method (GS stored at 0°C) but decreased linearly at a rate of 7.3 mm Hg/h when stored in a GS at 22°C. In contrast, Po2 increased when blood was stored at 0°C in a GPPS and PSBGA or at 22°C in a GPPS; however, Po2 did not change when blood was stored at 22°C in a PSBGA. Calculated values for plasma concentration of HCO3 and total CO2 concentration remained constant in the 3 syringe types when blood was stored at 22°C for 2 hours but increased when blood was stored in a GS or GPPS at 0°C. Conclusions and Clinical Relevance: Blood samples for blood gas and acid-base analysis should be collected into a GS and stored at 0°C or collected into a PSBGA and stored at room temperature.
Afficher plus [+] Moins [-]Effects of dopamine and dobutamine on isoflurane-induced hypotension in Hispaniolan Amazon parrots (Amazona ventralis)
2012
Schnellbacher, Rodney W. | Da Cunha, Anderson F. | Beaufrere, Hugues | Queiroz, Patricia | Nevarez, Javier G. | Tully, Thomas N. Jr
Objective: To assess the effects of dopamine and dobutamine on the blood pressure of isoflurane-anesthetized Hispaniolan Amazon parrots (Amazona ventralis). Animals: 8 Hispaniolan Amazon parrots. Procedures: A randomized crossover study was conducted. Each bird was anesthetized (anesthesia maintained by administration of 2.5% isoflurane in oxygen) and received 3 doses of each drug during a treatment period of 20 min/dose. Treatments were constant rate infusions (CRIs) of dobutamine (5, 10, and 15 μg/kg/min) and dopamine (5, 7, and 10 μg/kg/min). Direct systolic, diastolic, and mean arterial pressure measurements, heart rate, esophageal temperature, and end-tidal partial pressure of CO2 were recorded throughout the treatment periods. Results: Mean ± SD of the systolic, mean, and diastolic arterial blood pressures at time 0 (initiation of a CRI) were 132.9 ± 22.1 mm Hg, 116.9 ± 20.5 mm Hg, and 101.9 ± 22.0 mm Hg, respectively. Dopamine resulted in significantly higher values than did dobutamine for the measured variables, except for end-tidal partial pressure of CO2. Post hoc multiple comparisons revealed that the changes in arterial blood pressure were significantly different 4 to 7 minutes after initiation of a CRI. Overall, dopamine at rates of 7 and 10 μg/kg/min and dobutamine at a rate of 15 μg/kg/min caused the greatest increases in arterial blood pressure. Conclusions and Clinical Relevance: Dobutamine CRI at 5, 10, and 15 μg/kg/min and dopamine CRI at 5, 7, and 10 μg/kg/min may be useful in correcting severe hypotension in Hispaniolan Amazon parrots caused by anesthesia maintained with 2.5% isoflurane.
Afficher plus [+] Moins [-]Lesion severity at processing as a predictor of Salmonella contamination of swine carcasses
2012
Hurd, H Scott | Yaeger, Michael J. | Brudvig, Jean M. | Taylor, Daniel D. | Wang, Bing
Objective-To measure the relationship between gross lesions in swine carcasses observed at a processing plant and Salmonella contamination and to determine whether nonexpert assessments of lesion status would correspond with swine pathologists' judgments. Animals-Carcasses of 202 conventionally raised and 156 antimicrobial-free pigs in a Midwestern US processing plant examined from December 2005 to January 2006. Procedures-4 replicates were conducted. For each, freshly eviscerated carcasses were identified as having or lacking visceral adhesions by a nonexpert evaluator and digital carcass photographs were obtained. Swab specimens were obtained from carcasses before the final rinse stage of processing, and bacterial culture for Salmonella spp and Enterococcus spp was performed. Subsequently, carcass photographs were numerically scored for lesion severity by 3 veterinary pathologists. Results were used to test the ability of lesion detection to predict bacterial contamination of carcasses and the agreement between judgments of the inexperienced and experienced assessors. Results-The probability of Salmonella contamination in carcasses with lesions identified at the abattoir was 90% higher than that in carcasses lacking lesions, after controlling for replicate identity and antimicrobial use. The receiver operating characteristic curve and Cohen κ indicated close agreement between lesion detection at the abattoir and by the 3 pathologists. Conclusions and Clinical Relevance-Findings indicated the presence of lesions could be used to predict Salmonella contamination of swine carcasses and that a nonexpert processing-line assessment of lesions could be used to discriminate between healthy and chronically ill swine before their entry into the human food supply.
Afficher plus [+] Moins [-]Expression of interleukin-8 and intercellular cell adhesion molecule-1 in the synovial membrane and cranial cruciate ligament of dogs after rupture of the ligament
2012
El-Hadi, Mustafa | Charavaryamath, Chandarshekhar | Aebischer, Andrea | Smith, C Wayne | Shmon, Cindy | Balajīta Siṅgha.
This cross-sectional clinical study compared inflammation, including expression of the chemokine interleukin (IL)-8 and intercellular cell adhesion molecule-1 (ICAM-1), in the stifle joints of 4 control dogs and 23 dogs with cranial cruciate ligament rupture (CCLR). The CCL, synovial membrane, meniscus, cartilage, and synovial fluid from the affected stifle joints of all the dogs were examined. Inflammatory cell counts were performed on the synovial fluid, and the tissues were processed for histologic study and immunohistochemical detection of IL-8 and ICAM-1. The synovial fluid from the stifle joints of the dogs with CCLR had an increased percentage of neutrophils (P = 0.054) and a decreased percentage of lymphocytes (P = 0.004) but not macrophages compared with the fluid from the control dogs. There was accumulation of inflammatory cells and increased expression of IL-8 and ICAM-1 in the vascular endothelium of the synovial membrane and the CCL of the dogs with CCLR. The increase in inflammatory cells in the stifle joints of dogs with CCLR may therefore be due to increased expression of IL-8 and ICAM-1 in the synovial membrane and the CCL after the injury. These data may help in understanding the mechanisms of inflammation associated with CCLR.
Afficher plus [+] Moins [-]Vector competence of Glossina austeni and Glossina brevipalpis for Trypanosoma congolense in KwaZulu-Natal, South Africa
2012
Motloang, Makhosazana(ARC-Onderstepoort Veterinary Institute) | Masumu, Justin(Universite Pedagogique Nationale) | Mans, Barend(ARC-Onderstepoort Veterinary Institute) | van den Bossche, Peter(Institute of Tropical Medicine) | Latif, Abdalla(ARC-Onderstepoort Veterinary Institute)
Tsetse-transmitted trypanosomosis (nagana) has been the cause of stock losses in the recent past and still presents a major problem to livestock owners in certain areas of KwaZulu-Natal, South Africa. Over 10 000 cattle mortalities were reported in the 1990 nagana outbreak. Although information on the distribution and abundance of the tsetse flies Glossina brevipalpis and Glossina austeni in KwaZulu-Natal exists, data on their vector competence are lacking. This study aimed to determine the rate of natural Trypanosoma congolense infection by field-collected as well as colony-reared flies of these species. A total of 442 field-collected G. brevipalpis and 40 G. austeni flies were dissected immediately after collection to determine their infection rates, whilst 699 G. brevipalpis and 49 G. austeni flies were fed on susceptible animals in 10 and four batches, respectively, for use in xenodiagnosis experiments. Teneral colony flies were fed on infected animals and dissected 21 days post infection to confirm their infectivity testing. Glossina austeni harboured 8% immature and mature infections. In G. brevipalpis, the infection with the immature stages was lower (1%) and no mature infections were observed. Although all four batches of G. austeni transmitted T. congolense to four susceptible animals, no transmission resulted from 10 batches of G. brevipalpis fed on susceptible cattle. Colonyderived G. austeni (534) and G. brevipalpis (882) were fed on four bovines infected with different T. congolense isolates. Both G. austeni and G. brevipalpis acquired trypanosome infection from the bovines, with immature infection ranges of 20% - 33% and 1% - 4%, respectively. Parasites, however, only matured in G. austeni (average = 4%). Glossina austeni plays a larger role in the epidemiology of animal trypanosomosis in KwaZulu-Natal than G. brevipalpis and therefore more focus should be aimed at the former when control measures are implemented.
Afficher plus [+] Moins [-]In vitro anti-tick properties of the essential oil of Tagetes minuta L. (Asteraceae) on Hyalomma rufipes (Acari: Ixodidae)
2012
Nchu, Felix(Cape Peninsula University of Technology Department of Horticultural Science) | Magano, Solomon R.(University of South Africa Department of Life and Consumer Sciences) | Eloff, Jacobus N.(University of Pretoria Department of Paraclinical Sciences)
In this study we examined the anti-tick properties of the essential oil of Tagetes minuta L. (Asteraceae: Asterales) against Hyalomma rufipes ticks. We obtained the essential oil of T. minuta by hydro-distillation of a combination of fresh flowers, leaves and soft stems, and analysed these by using gas chromatography (GC) and gas chromatography-linked mass spectrometry (GC-MS). The oil had a high percentage of monoterpenes and the major compounds identified were cis-ocimene (28.5%), beta-ocimene (16.83%) and 3-methyl-2-(2-methyl-2-butenyl)-furan (11.94%). Hyalomma rufipes adults displayed a significant (P < 0.05) dose repellent response to the essential oil of T. minuta. Probit analysis indicated a repellent EC50 of T. minuta essential oil for male ticks to be 0.072 mL/mL (CI 0.053 mL/mL to 0.086 mL/mL) and 0.070 mL/mL (CI 0.052 mL/mL to 0.084 mL/mL) for female ticks. There were no significant differences in repellent responses between male and female ticks. The oil also significantly (P < 0.05) delayed moulting of 60% of H. rufipes engorged nymphs. These results suggest that T. minuta may be a potential source of anti-tick agents.
Afficher plus [+] Moins [-]Detection of Haemophilus parasuis isolates from South China by loop-mediated isothermal amplification and isolate characterisation
2012
Zhang, Jian-min(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Shen, Hai-yan(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Liao, Ming(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Ren, Tao(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Guo, Li-li(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Xu, Cheng-gang(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Feng, Sai-xiang(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Fan, Hui-ying(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Li, Jing-yi(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Chen, Ji-dang(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture) | Zhang, Bin(South China Agricultural University The Key Laboratory of Animal Disease Control and Prevention of the Ministry of Agriculture)
Haemophilus parasuis is the etiological agent of Glässer's disease, which is characterised by fibrinous polyserositis, meningitis and polyarthritis, causing severe economic losses to the swine industry. In this study, a loop-mediated isothermal amplification (LAMP) test was developed to improve the specificity, facility and speed of diagnosis of H. parasuis isolates. The LAMP assay rapidly amplified the target gene within 50 min incubation at 63 °C in a laboratory water bath. The LAMP amplicon could be visualised directly in the reaction tubes following the addition of SYBR Green I dye. The detection limit of this LAMP method was 10 CFU/mL, which was 10 times more sensitive than the earlier 16S rRNA polymerase chain reaction (PCR) test conducted by Oliveira, Galina and Pijoan (2001), and no cross-reactivity was observed from other non-H. parasuis strains. This LAMP test was evaluated further on 187 clinical specimens from pigs suspected of being infected with H. parasuis. Forty-three were found positive by bacterial isolation of H. parasuis, as well as by the 16S rRNA PCR and LAMP tests. The 43 H. parasuis isolates were classified into 9 serovars and had 37 genetic patterns when analysed by pulsed-field gel electrophoresis (PFGE). This displayed that various H. parasuis serovars and genotypes were widely distributed in South China. Therefore, the speed, specificity and sensitivity of the LAMP test, the lack of a need for expensive equipment, and the visual readout showed great potential for a correct clinical diagnosis of H. parasuis in favour of controlling Glässer's disease
Afficher plus [+] Moins [-]Natural hosts of the larvae of Nuttalliella sp. (N. namaqua?) (Acari: Nuttalliellidae)
2012
Horak, Ivan G.(University of Pretoria Department of Veterinary Tropical Diseases) | Lutermann, Heike(University of Pretoria Department of Zoology and Entomology) | Medger, Katarina(University of Pretoria Department of Zoology and Entomology) | Apanaskevich, Dmitry A.(United States National Tick Collection) | Matthee, Conrad A.(Stellenbosch University Department of Botany and Zoology)
The first collection of unengorged and fully engorged larvae of Nuttalliella sp. (N. namaqua?) from the murid rodents Micaelamys namaquensis, Aethomys chrysophilus and Acomys spinosissimus in Limpopo Province and from M. namaquensis in the Northern Cape Province, South Africa, is documented. A total of nine larvae were collected from two M. namaquensis in the Soutpansberg mountain range in the Limpopo Province during April 2009. During the last week of September 2011, 221 larvae were collected from rodents at the same locality and 10 of 48 M. namaquensis, 6 of 12 Ae. chrysophilus and 3 of 14 Ac. spinosissimus were infested. One of the M. namaquensis harboured 53 larvae. Five larvae were collected from two M. namaquensis in the Northern Cape Province. Total genomic DNA was extracted from two larvae and a region of the 18S rRNA gene was sequenced for these. BLASTn searches revealed similarity between these specimens and the Nuttalliella sequences published on GenBank.
Afficher plus [+] Moins [-]Comparing effects of freezing at -196 ºC and -20 ºC on the viability of mastitis pathogens
2012
Petzer, Inge-Marie(University of Pretoria Department of Production Animal Studies) | Karzis, Joanne(University of Pretoria Department of Production Animal Studies) | van der Schans, Theodorus J.(University of Pretoria Department of Production Animal Studies) | Watermeyer, Johanna C.(University of Pretoria Department of Production Animal Studies) | Mitchell-Innes, Norman(Herd Husbandry Help CC) | Eloff, Stephanie(University of Pretoria Department of Production Animal Studies) | Fosgate, Geoffrey T.(University of Pretoria Department of Production Animal Studies)
The aim of this study was to compare the effects of cryopreservation at approximately -196 ºC in liquid nitrogen (N) and freezing at approximately -20 ºC in a freezer, on the viability and survival of eight different mastitogenic bacteria inoculated in milk. Bacteria were frozen at approximately -20 ºC in a freezer and cryopreserved at approximately -196 ºC in liquid nitrogen. An effective preservation method was needed for follow-up samples from cows identified in the South African National Milk Recording Scheme (NMRS) with somatic cell counts above 250 000 cells/mL milk. The organisation responsible for sample collection of the NMRS milk samples also provides producers with liquid nitrogen for their semen flasks at the collection sites. This existing mode of storage and transport could therefore be utilised. Ten samples of each organism were thawed and cultured bi-weekly until week 18 for both temperature treatments. An additional sampling was performed at week 30 for samples frozen at approximately -20 ºC. Freezing and cryopreservation did not impair subsequent isolation of Streptococcus dysgalactiae, Streptococcus uberis, Enterococcus faecalis, Staphylococcus aureus (STH) (phage type lytic group III) or Sta. aureus (STA) (phage typed, other than lytic group III). Survival was indicated by the isolation of bacteria from samples, and viability by the strength of growth of the bacteria isolated. The survival of Streptococcus agalactiae decreased after week 12 and Escherichia coli after week 16 of freezing, but both organisms survived under cryogenic preservation until week 18. Coagulase-negative staphylococci survived until week 18 for both freezing and cryogenic preservation. Both storage methods could thus contribute to the improvement of a pro-active approach towards udder health management in South African dairy herds.
Afficher plus [+] Moins [-]Towards One Health disease surveillance: The Southern African Centre for Infectious Disease Surveillance approach
2012
Karimuribo, Esron D.(Southern African Centre for Infectious Disease Surveillance) | Sayalel, Kuya(Ngorongoro Conservation Area Authority) | Beda, Eric(Southern African Centre for Infectious Disease Surveillance) | Short, Nick(Royal Veterinary College) | Wambura, Philemon(Southern African Centre for Infectious Disease Surveillance) | Mboera, Leonard G.(National Institute for Medical Research) | Kusiluka, Lughano J.M.(The Open University of Tanzania) | Rweyemamu, Mark M.(Southern African Centre for Infectious Disease Surveillance)
Africa has the highest burden of infectious diseases in the world and yet the least capacity for its risk management. It has therefore become increasingly important to search for 'fit-for-purpose' approaches to infectious disease surveillance and thereby targeted disease control. The fact that the majority of human infectious diseases are originally of animal origin means we have to consider One Health (OH) approaches which require inter-sectoral collaboration for custom-made infectious disease surveillance in the endemic settings of Africa. A baseline survey was conducted to assess the current status and performance of human and animal health surveillance systems and subsequently a strategy towards OH surveillance system was developed. The strategy focused on assessing the combination of participatory epidemiological approaches and the deployment of mobile technologies to enhance the effectiveness of disease alerts and surveillance at the point of occurrence, which often lies in remote areas. We selected three study sites, namely the Ngorongoro, Kagera River basin and Zambezi River basin ecosystems. We have piloted and introduced the next-generation Android mobile phones running the EpiCollect application developed by Imperial College to aid geo-spatial and clinical data capture and transmission of this data from the field to the remote Information Technology (IT) servers at the research hubs for storage, analysis, feedback and reporting. We expect that the combination of participatory epidemiology and technology will significantly improve OH disease surveillance in southern Africa.
Afficher plus [+] Moins [-]