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Evaluation of horizontal transmission of bovine viral diarrhea virus type 1a from experimentally infected white-tailed deer fawns (Odocoileus virginianus) to colostrum-deprived calves
2012
Negron, Maria E. | Pogranichniy, Roman M. | Van Alstine, William | Hilton, W Mark | Lévy, Michel Louis | Raizman, Eran A.
Objective: To assess the transmission of bovine viral diarrhea virus (BVDV) from experimentally infected white-tailed deer fawns to colostrum-deprived calves by use of a BVDV strain isolated from hunter-harvested white-tailed deer. Animals: 5 white-tailed deer (Odocoileus virginianus) fawns and 6 colostrum-deprived calves. Procedures: Fawns were inoculated intranasally with a noncytopathic BVDV-1a isolate (2 mL containing 10(6.7) TCID(50)/mL), and 2 days after inoculation, animals were commingled until the end of the study. Blood and serum samples were obtained on days −6, 0, 7, 14, and 21 after inoculation for reverse transcriptase PCR assay, virus neutralization, and BVDV-specific antibody ELISA. Nasal, oral, and rectal swab specimens were collected on days 0, 3, 7, 14, 17, and 21 for reverse transcriptase PCR testing. By 21 days after inoculation, all animals were euthanized and necropsied and tissues were collected for histologic evaluation, immunohistochemical analysis, and virus isolation. Results: All fawns became infected and shed the virus for up to 18 days as determined on the basis of reverse transcriptase PCR testing and virus isolation results. Evidence of BVDV infection as a result of cohabitation with acutely infected fawns was detected in 4 of the 6 calves by means of reverse transcriptase PCR testing and virus isolation. Conclusions and Clinical Relevance: On the basis of these findings, BVDV transmission from acutely infected fawns to colostrum-deprived calves appeared possible.
Mostrar más [+] Menos [-]In vitro effect of hydroxyethyl starch 130/0.42 on canine platelet function
2012
Classen, Janine | Adamik, Katja N. | Weber, Karin | Rubenbauer, Stephanie | Hartmann, Katrin
Objective: To evaluate the effect of 6% hydroxyethyl starch (HES) solution, with a molecular weight of 130 kDa and a degree of substitution of 0.42, on canine platelet function in vitro. Samples: Blood samples from 31 healthy adult dogs. Procedures: Citrated blood was diluted with saline (0.9% NaCl) solution or HES 130/0.42 in ratios of 1:9 (ie, 1 part saline solution or HES 130/0.42 and 9 parts blood) and 1:3. Platelet plug formation time (closure time [Ct]) was measured with a platelet function analyzer and cartridges coated with collagen and ADP. Results: Median baseline Ct with citrated blood was 84.0 seconds (interquartile range, 74.5 to 99.5 seconds). Results obtained with 1:9 dilutions with saline solution and HES 130/0.42 were not significantly different from baseline results. The 1:3 dilutions with saline solution and HES 130/0.42 resulted in median Cts of 96.0 seconds (interquartile range, 85.5 to 110.8 seconds) and 112.0 seconds (92.0 to 126.0 seconds), respectively. Results obtained with both 1:3 dilutions were significantly different from baseline results. The Ct obtained with the HES dilution was also significantly different from that of the 1:3 dilution with saline solution. Conclusions and Clinical Relevance: Saline solution and HES 130/0.42 in a 1:3 dilution affected canine platelet function by prolonging Cts. The HES 130/0.42 had a significantly greater effect on canine platelets than did saline solution.
Mostrar más [+] Menos [-]Epidural anesthesia and postoperatory analgesia with alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy in bitches
2012
Pohl, Virginia H. | Carregaro, Adriano B. | Lopes, Carlize | Gehrcke, Martielo I. | Muller, Daniel C.M. | Garlet, Clarissa D.
The aim of this study was to determine the viability and cardiorespiratory effects of the association of epidural alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy (OH) in bitches. Forty-two bitches were spayed under epidural anesthesia with 2.5 mg/kg body weight (BW) of 1% lidocaine with adrenaline (CON) or in association with 0.25 mg/kg BW of xylazine (XYL), 10 μg/kg BW of romifidine (ROM), 30 μg/kg BW of detomidine (DET), 2 μg/kg BW of dexmedetomidine (DEX), or 5 μg/kg BW of clonidine (CLO). Heart rate (HR), respiratory rate (fR) and arterial pressures were monitored immediately before and every 10 min after the epidural procedure. Blood gas and pH analysis were done before, and at 30 and 60 min after the epidural procedure. Animals were submitted to isoflurane anesthesia if they presented a slightest sign of discomfort during the procedure. Time of sensory epidural block and postoperative analgesia were evaluated. All animals in CON and DEX, 5 animals in ROM and CLO, 4 animals in XYL, and 3 in DET required supplementary isoflurane. All groups, except CLO, showed a decrease in HR. There was an increase in arterial pressures in all groups. Postoperative analgesia lasted the longest in XYL. None of the protocols were totally efficient to perform the complete procedure of OH; however, xylazine provided longer postoperative analgesia than the others.
Mostrar más [+] Menos [-]Tuberculosis cross-species transmission in Tanzania: Towards a One-Health concept
2012
Erasto V. Mbugi | Bugwesa Z. Katale | Sharon Kendall | Liam Good | Gibson S. Kibiki | Julius D. Keyyu | Peter Godfrey-Faussett | Paul van Helden | Mecky I. Matee
For centuries, tuberculosis, which is a chronic infection caused by the bacillus <em>Mycobacterium tuberculosis</em> has remained a global health problem. The global burden of tuberculosis has increased, particularly in the Southern African region, mainly due to HIV, and inadequate health systems which has in turn given rise to emergent drug resistant tuberculosis (TB) strains. Bovine tuberculosis (BTB) has also emerged as a significant disease with the tendency for inter-species spread. The extent of interspecies BTB transmission both in urban and rural communities has not been adequately assessed. The phenomenon is of particular importance in rural communities where people share habitats with livestock and wildlife (particularly in areas near national parks and game reserves). Aerosol and oral intake are the major routes of transmission from diseased to healthy individuals, with health care workers often contracting infection nosocomially. Although TB control has increasingly been achieved in high-income countries, the disease, like other poverty-related infections, has continued to be a disaster in countries with low income economies. Transmission of infections occurs not only amongst humans but also between animals and humans (and occasionally vice versa) necessitating assessment of the extent of transmission at their interface. This review explores tuberculosis as a disease of humans which can cross-transmit between humans, livestock and wildlife. The review also addresses issues underlying the use of molecular biology, genetic sequencing and bioinformatics as t tools to understand the extent of inter-species cross-transmission of TB in a ‘One Health’ context.
Mostrar más [+] Menos [-]New technologies to diagnose and monitor infectious diseases of livestock: Challenges for sub-Saharan Africa
2012
Donald P. King | Miki Madi | Valerie Mioulet | Jemma Wadsworth | Caroline F. Wright | Begoña Valdazo-González | Nigel P. Ferris | Nick J. Knowles | Jef Hammond
Using foot-and-mouth disease (FMD) as an example, this review describes new tools that can be used to detect and characterise livestock diseases. In recent years, molecular tests that can detect and characterise pathogens in a diverse range of sample types have revolutionised laboratory diagnostics. In addition to use in centralised laboratories, there are opportunities to locate diagnostic technologies close to the animals with suspected clinical signs. Work in this area has developed simple-to-use lateral-flow devices for the detection of FMD virus (FMDV), as well as new hardware platforms to allow molecular testing to be deployed into the field for use by non-specialists. Once FMDV has been detected, nucleotide sequencing is used to compare field strains with reference viruses. Transboundary movements of FMDV are routinely monitored using VP1 sequence data, while higher resolution transmission trees (at the farm-to-farm level) can be reconstructed using full-genome sequencing approaches. New technologies such as next-generation sequencing technologies are now being applied to dissect the viral sequence populations that exist within single samples. The driving force for the use of these technologies has largely been influenced by the priorities of developed countries with FMD-free (without vaccination) status. However, it is important to recognise that these approaches also show considerable promise for use in countries where FMD is endemic, although further modifications (such as sample archiving and strain and serotype characterisation) may be required to tailor these tests for use in these regions. Access to these new diagnostic and sequencing technologies in sub-Saharan Africa have the potential to provide novel insights into FMD epidemiology and will impact upon improved strategies for disease control. Effective control of infectious diseases is reliant upon accurate diagnosis of clinical cases using laboratory tests, together with an understanding of factors that impact upon the epidemiology of the infectious agent. A wide range of new diagnostic tools and nucleotide sequencing methods are used by international reference laboratories to detect and characterise the agents causing outbreaks of infectious diseases. In the past, high costs (initial capital expenses, as well as day-to-day maintenance and running costs) and complexity of the protocols used to perform some of these tests have limited the use of these methods in smaller laboratories. However, simpler and more cost-effective formats are now being developed that offer the prospect that these technologies will be even more widely deployed into laboratories particularly those in developing regions of the world such as sub-Saharan Africa.
Mostrar más [+] Menos [-]Epidemiological perspectives of ticks and tick-borne diseases in South Sudan: Cross-sectional survey results
2012
Fredrick M. Kivaria | Angolwisye M. Kapaga | Gabriel K. Mbassa | Paul F. Mtui | Rhombe J. Wani
A cross-sectional study was conducted between September and October 2010 in five states of South Sudan that were selected on the basis of the perceived risk of tick-borne diseases. The purpose was to investigate epidemiological parameters of tick-borne diseases in South Sudan and their uses in future control strategies. A total of 805 calves were assessed by clinical, microscopic and serological examination and tick counts. The indirect Enzyme-Linked Immuno-Sorbent Assay (ELISA) was used to detect antibodies to<em> Theileria parva</em>, <em>Theileria mutans</em>, <em>Anaplasma marginale</em> and <em>Babesian bigemina</em>. Sero-conversion risks for <em>T. parva</em> and <em>T. mutans</em> were 27.3% and 31.3% respectively, whilst the risk was 57.6% and 52.8% for <em>A. marginale</em> and <em>B. bigemina</em>, respectively. Major tick species identified include <em>Rhipicephalus appendiculatus</em>, <em>Rhipicephalus decoloratus</em>, <em>Rhipicephalus microplus</em>, <em>Amblyomma variegatum</em>, and <em>Rhipicephalus evertsi</em>. There was great variation (<em>P</em> ≤ 0.001) in the number of all these ticks, both between herds in a state and between calves in an individual herd. The low and intermediate sero-conversion risks observed in the study states suggest that immunisation against East Coast fever (ECF) is justified. Fortunately, three major genotypes that were identified by applying Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCRRFLP) analysis on the p104 to the blood samples and T. parva Muguga, matched very well with <em>T. parva</em> Kiambu 5 and <em>T. parva</em> Muguga; therefore the Muguga cocktail can be used for the immunisation of cattle in South Sudan. However, prospective studies are required to develop optimal control measures for tick-borne diseases under different ecological and husbandry practices in South Sudan.
Mostrar más [+] Menos [-]Effect of packing on changes in erythrocyte osmotic fragility and malondialdehyde concentration in donkeys administered with ascorbic acid
2012
Folashade Olaifa | Joseph O. Ayo | Suleiman F. Ambali | Peter I. Rekwot
Experiments were performed with the aim of investigating the effect of packing on erythrocyte osmotic fragility (EOF) and malondialdehyde (MDA) concentration in donkeys, and the effect of ascorbic acid (AA). Twelve apparently healthy donkeys raised under the traditional extensive system served as experimental subjects. Six donkeys administered orally with AA (200 mg/kg) and subjected to packing were used as experimental animals, whilst six others not administered with AA served as controls. Blood samples were collected pre- and post-packing from all the donkeys for the determination of MDA and EOF. At 0.3% Sodium Chloride (NaCl) concentration, the percentage haemolysis was 93.69% ± 2.21% in the control donkeys and the value was significantly (<em>P</em> < 0.05) higher than the value of 71.31% ± 8.33%, recorded in the experimental donkeys. The post-packing MDA concentration obtained in the control donkeys was 39.62 µmol ± 4.16 µmol, and was not significantly different (<em>P</em> > 0.05) from the value of 35.97 µmol ± 2.88 µmol recorded in the experimental donkeys. In conclusion, the increase in haemolysis obtained in the donkeys suggested that packing induced oxidative stress, which was ameliorated by AA administration.
Mostrar más [+] Menos [-]Molecular characterisation of Newcastle disease virus isolates from different geographical regions in Mozambique in 2005
2012
Raul Fringe | Anna-Mari Bosman | Karen Ebersohn | Shahn Bisschop | Celia Abolnik | Estelle Venter
Newcastle disease (ND) is regarded as a highly contagious and economically important disease in poultry and has a worldwide distribution. Viral determinants for Newcastle disease virus (NDV) virulence are not completely understood and viruses of different pathotypes can be found at live-bird markets in different geographical areas. The prevalence of Newcastle disease in village poultry in Mozambique is not well documented and strains of NDV involved in yearly outbreaks are unknown. The fusion (F) protein is an important determinant of pathogenicity of the virus and is used commonly for phylogenetic analysis. Newcastle disease viruses from various geographical regions of Mozambique were sequenced and compared genetically to published sequences obtained from GenBank. Samples were collected in three different areas of Mozambique and NDV was isolated by infection of embryonated chicken eggs. Sequence analysis of the F-protein encoding gene was used to classify 28 isolates from Mozambique into genotypes and compare these genotypes phylogenetically with existing genotypes found in GenBank. The isolates obtained from Mozambique grouped mainly into two clades. In the first clade, 12 isolates grouped together with sequences of isolates representing genotypes from Mozambique that were previously described. In the second clade, 16 isolates group together with sequences obtained from GenBank originating from Australia, China, South Africa and the USA. Eleven of these isolates showed a high similarity with sequences from South Africa. The number of samples sequenced (<em>n</em> = 28), as well as the relatively small geographical collection area used in this study, are too small to be a representation of the circulating viruses in Mozambique in 2005. Viruses characterised in this study belonged to lineage 5b, a similar finding of a previous study 10 years ago. From this data, it merely can be concluded that no new introduction of the virus occurred from 1995 to 2005 in Mozambique.
Mostrar más [+] Menos [-]Towards one Africa, one health: The Southern African Centre for Infectious Disease Surveillance One Health focus on infectious diseases
2012
Mark M. Rweyemamu | Janusz Paweska | Dominic Kambarage | Filomena Namuba
Towards One Health Knowledge Networks: A Southern African Centre of Infectious Disease Surveillance case study
2012
Eric Beda
The dynamic nature of new information and/or knowledge is a big challenge for information systems. Early knowledge management systems focused entirely on technologies for storing, searching and retrieving data; these systems have proved a failure. Juirsica and Mylopoulos1 suggested that in order to build effective technologies for knowledge management, we need to further our understanding of how individuals, groups and organisations use knowledge. As the focus on knowledge management for organisations and consortia alike is moving towards a keen appreciation of how deeply knowledge is embedded in people’s experiences, there is a general realisation that knowledge cannot be stored or captured digitally. This puts more emphasis in creating enabling environments for interactions that stimulate knowledge sharing. Our work aims at developing an un-obtrusive intelligent system that glues together effective contemporary and traditional technologies to aid these interactions and manage the information captured. In addition this system will include tools to aid propagating a repository of scientific information relevant to surveillance of infectious diseases to complement knowledge shared and/or acts as a point of reference. This work is ongoing and based on experiences in developing a knowledge network management system for the Southern African Centre of Infectious Disease Surveillance (SACIDS), A One Health consortium of southern African academic and research institutions involved with infectious diseases of humans and animals in partnership with world-renowned centres of research in industrialised countries.
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