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Molecular identification of <i>Cordylobia anthropophaga</i > Blanchard (Diptera: Calliphoridae) larvae collected from dogs (<i>Canis familiaris</i>) in Jos South, Plateau State, Nigeria
2012
Ndudim I. Ogo | Emmanuel Onovoh | Oluyinka O. Okubanjo | Ruth C. Galindo | Jose-Manuel P. de la Lastra | Jose de la Fuente
Myiasis-causing larvae were extracted from dogs attending veterinary clinics in Plateau State, Nigeria and subjected to molecular analysis involving polymerase chain reaction amplification of the 28S rRNA gene of blowflies, cloning and sequencing techniques. All larvae were confirmed as Cordylobia anthropophaga Blanchard (Diptera: Calliphoridae) after the initial morphological identification. This is the first molecular identification of any myiasis-causing fly species in Nigeria and may serve as a reliable alternative to morphological identification where samples are not well preserved or difficult to identify to species level.
Mostrar más [+] Menos [-]<i>Bartonella</i> spp. in human and animal populations in Gauteng, South Africa, from 2007 to 2009
2012
Anastasia N. Trataris | Jennifer Rossouw | Lorraine Arntzen | Allan Karstaedt | John Frean
Bartonellae are highly adaptive organisms that have the ability to evade the host immune system and cause persistent bacteraemia by occupying the host’s erythrocytes. Bartonella spp. is under-studied and health care professionals often misdiagnose Bartonella-related infections. The aim of this study was to investigate the carriage of Bartonella spp. circulating in human and animal populations in Gauteng using culturing and polymerase chain reaction (PCR) detection. A total of 424 human, 98 cat, 179 dog, and 124 wild rodent blood samples were plated onto specialised media and incubated for 7–21 days at 37 ºC in CO2. Culture isolates morphologically similar to Bartonella control strains were confirmed by PCR and sequenced to determine species. Deoxyribonucleic acid (DNA) was extracted from all blood samples and tested by nested PCR. Bartonella could only be cultured from the cat and rodent specimens. Cat isolates were > 99% similar to Bartonella henselae URBHLIE 9, previously isolated from an endocarditis patient, and rat isolates were > 98% similar to either RN24BJ (candidus ‘Bartonella thailandensis’) or RN28BJ, previously isolated from rodents in China. The PCR prevalences were 22.5% in HIV-positive patients, 9.5% in clinically healthy volunteers, 23.5% in cats, 9% in dogs and 25% in rodents. Findings of this study have important implications for HIV-positive patients.
Mostrar más [+] Menos [-]Rift Valley fever: Real or perceived threat for Zambia?
2012
George Dautu | Calvin Sindato | Aaron S. Mweene | Kenny L. Samui | Polly Roy | Robert Noad | Janusz Paweska | Phelix A.O. Majiwa | Antony Musoke
Rift Valley fever (RVF) in Zambia was first reported in 1974 during an epizootic of cattle and sheep that occurred in parts of Central, Southern and Copperbelt Provinces. In 1990, the disease was documented in nine districts of the provinces of Zambia. In the last two decades, there have been no reports of RVF. This long period without reported clinical disease raises questions as to whether RVF is a current or just a perceived threat. To address this question, World Organisation for Animal Health (OIE) disease occurrence data on RVF for the period 2005−2010 in the Southern Africa Development Community (SADC) was analysed. From the analysis, it was evident that most countries that share a common border with Zambia had reported at least one occurrence of the disease during the period under review. Due to the absence of natural physical barriers between Zambia and most of her neighbours, informal livestock trade and movements is a ubiquitous reality. Analysis of the rainfall patterns also showed that Zambia received rains sufficient to support a mosquito population large enough for high risk of RVF transmission. The evidence of disease occurrence in nearby countries coupled with animal movement, and environmental risk suggests that RVF is a serious threat to Zambia. In conclusion, the current occurrence of RVF in Zambia is unclear, but there are sufficient indications that the magnitude of the circulating infection is such that capacity building in disease surveillance and courses on recognition of the disease for field staff is recommended. Given the zoonotic potential of RVF, these measures are also a prerequisite for accurate assessment of the disease burden in humans.
Mostrar más [+] Menos [-]Ticks (Acari: Ixodidae) infesting cattle and African buffaloes in the Tsavo conservation area, Kenya
2012
Edward K. Kariuki | Barend L. Penzhorn | Ivan G. Horak
Several ixodid tick species are shared between domestic cattle and African buffaloes (<em>Syncerus caffer</em>). So too, are a number of tick-borne diseases. The aim of the study was to compare the species composition of ticks that infest cattle and buffaloes utilising the same habitat within the Tsavo Conservation Area, Kenya. To this end, 25 cattle and 62 buffaloes were each opportunistically sampled for ticks on a single occasion in February 2010. Eight species, namely <em>Amblyomma gemma</em>, <em>Amblyomma lepidum</em>, <em>Hyalomma albiparmatum</em>, <em>Hyalomma rufipes</em>, <em>Hyalomma truncatum</em>, <em>Rhipicephalus evertsi evertsi</em>, <em>Rhipicephalus pravus</em> and <em>Rhipicephalus pulchellus</em> infested both cattle and buffaloes. Three species, <em>Rhipicephalus</em> (<em>Boophilus</em>) sp., <em>Rhipicephalus kochi</em>, and <em>Rhipicephalus muehlensi</em> were collected only from cattle, and three species,<em> Hyalomma impeltatum</em>, <em>Rhipicephalus humeralis</em> and<em> Rhipicephalus praetextatus</em> were present only on buffaloes. The attachment sites of the various tick species were also recorded. New locality records for <em>H. impeltatum</em> and <em>H. truncatum</em> and the first confirmed locality record for <em>Rhipicephalus praetextatus sensu stricto</em> in Kenya were documented.
Mostrar más [+] Menos [-]Isolation and characterization of neural progenitor cells from adult canine brains
2012
Lim, Ji-Hey | Koh, Sehwon | Olby, Natasha J. | Piedrahita, Jorge | Mariani, Christopher L.
Objective: To isolate and characterize neural stem and progenitor cell populations in the brain of adult dogs. Animals: 7 healthy adult dogs. Procedures: Dogs (age, 10 to 60 months) were euthanized for reasons unrelated to the study. The subventricular zone (SVZ) adjacent to the lateral ventricles and subgranular zone (SGZ) of the hippocampus were isolated and used to generate single cell suspensions for nonadherent culture. The resulting primary neurospheres were serially passaged to assess self-renewal capacity. Neurospheres were differentiated by the withdrawal of growth factors and the addition of serum. Differentiated and undifferentiated neurospheres were analyzed via reverse transcriptase PCR assay or immunocytochemical staining for markers of pluripotency and neural lineage. Results: Neurospheres were generated from the SVZ and SGZ in all dogs. The SVZ generated more primary neurospheres than did the SGZ. Serial passage was successful, although few neurospheres could be generated after the fifth passage. Undifferentiated neurospheres were positive for SOX2, nestin, and glial fibrillary acidic protein (GFAP) and negative for OCT4 and NANOG. After differentiation, GFAP, neuronal class III β-tubulin, and 2′, 3′-cyclic nucleotide 3′-phosphodiesterase–positive progeny were noted migrating out of the neurospheres. Conclusions and Clinical Relevance: Results suggested the persistence of SOX2-positive, nestin-positive, GFAP-positive, OCT4-negative, and NANOG-negative neural progenitor cells in the SVZ and SGZ regions of mature canine brains, which are capable of producing multiple cell lineages. This study may serve as a basis for future studies investigating the role of these cells in various disease processes, such as neoplasia, or for regenerative purposes.
Mostrar más [+] Menos [-]Antimicrobial susceptibility and molecular subtypes of Staphylococcus aureus isolated from pig tonsils and cow’s milk in China
2012
Zhang, Chunping | Song, Li | Chen, Huijuan | Liu, Yang | Ning, Yibao | Qin, Yuling
This study investigated and compared the antimicrobial resistance patterns and ribotypes of Staphylococcus aureus isolated from pig tonsils and cow’s milk in China. A total of 90 isolates of S. aureus was included: 42 strains were isolated from tonsils of pigs and 48 from half-udder milk. The broth microdilution method and the double-disc diffusion test (D test) were used for antimicrobial susceptibility testing. The mecA gene for methicillin-resistant S. aureus (MRSA) and the ermA, ermB, ermC, and msrA genes for erythromycin-resistant strains were detected by polymerase chain reaction (PCR). The isolates were ribotyped with the Riboprinter system. The highest frequency of resistance was observed with clindamycin (91.1%), followed by penicillin (90.0%), and erythromycin (85.6%). All strains were susceptible to vancomycin and trimethoprim-sulfamethoxazole. The D test showed that 54.5% (42/77) of erythromycin-resistant isolates had the constitutive resistance phenotype and 45.5% (35/77) had the inducible resistance phenotype to clindamycin. A higher proportion of resistance to cephalosporins, macrolides, fluoroquinolones, and pleuromutilins was observed in pig isolates than in milk isolates (P < 0.05). The mecA gene was detected in all MRSA isolates; 89.6% of erythromycin-resistant strains harbored the ermC gene and 16.9% harbored the ermB gene. A total of 35 different ribogroups was found among the isolates investigated; 83.3% of pig strains belonged to 1 cluster with a similarity coefficient of 0.84. In contrast, 3 main clusters were observed among 68.8% of milk strains, which indicates a high degree of host specificity.
Mostrar más [+] Menos [-]Evaluation of the onset of protection induced by a modified-live virus vaccine in calves challenge inoculated with type 1b bovine viral diarrhea virus
2012
Palomares, Roberto A. | Givens, M Daniel | Wright, James C. | Walz, Paul H. | Brock, Kenny V.
Objective: To evaluate onset of protection induced by modified-live virus (MLV) bovine viral diarrhea virus (BVDV) vaccine administered 7, 5, or 3 days before inoculation with type 1b BVDV (strain NY-1). Animals: 40 calves. Procedures: Calves were assigned to 4 groups: an unvaccinated control group or groups vaccinated with MLV vaccine containing BVDV types 1a and 2 at 7, 5, or 3 days, before inoculation with NY-1 BVDV. Blood samples were collected for leukocyte counts, serum virus neutralization, and virus isolation (VI); nasal swab specimens (NSSs) were obtained for VI, and rectal temperatures were monitored for 14 days after inoculation. Results: No significant differences in leukocyte counts or rectal temperatures were detected after BVDV inoculation in vaccinated calves. Vaccinated calves had reduced viremia and viral shedding after inoculation, compared with results for unvaccinated calves. On day 5 after inoculation, a higher proportion of calves vaccinated 3 days before inoculation had positive VI from NSSs, compared with NSS VI results for calves vaccinated 5 and 7 days before inoculation. Unvaccinated calves had leukopenia on days 3, 5, and 6 and had higher rectal temperatures on days 7 and 8 after inoculation, compared with temperatures before inoculation. All unvaccinated calves had ≥ 1 positive VI result from NSSs 3 to 11 days after inoculation, and 4 became viremic. Conclusions and Clinical Relevance: MLV BVDV vaccine prevented fever, viremia, and leukopenia in calves challenge inoculated with NY-1 BVDV. A high proportion of calves vaccinated 3 days before inoculation shed BVDV after inoculation.
Mostrar más [+] Menos [-]Effects of in vitro exposure to autologous blood and serum on expression of interleukin-8, interleukin-1β, and chemokine (C-X-C motif) ligand 2 in equine primary bronchial epithelial cell cultures
2012
Ainsworth, Dorothy M. | Reyner, Claudia L.
Objective: To examine the effects of in vitro exposure to solutions of autologous horse blood (AHB) and autologous horse serum (AHS) on expressions of selected cytokine genes in equine primary bronchial epithelial cell (BEC) cultures and to contrast these responses to those induced in BEC cultures by endotoxin and hay dust. Sample: BEC cultures established from bronchi of 6 healthy horses. Procedures: 5-day-old BEC cultures were treated with PBS solution, AHB (2 concentrations), AHS, hay dust solution, and lipopolysaccharide solution for 24 hours. Gene expressions of interleukin (IL)-8, IL-1β, chemokine (C-X-C motif) ligand 2 (CXCL2), and glyceralde-hyde-3-phosphate dehydrogenase were subsequently measured with a kinetic PCR assay. Results: With the exception of AHS, all treatments of the BECs resulted in upregulation of each target gene expression relative to its expression in cultures exposed to PBS solution. Treatment with AHB induced a dose-dependent increase of each target gene, with IL-1β expression increasing the most (> 1,200-fold increase). Lipopolysaccharide and hay dust solution treatments each resulted in 20-fold increases in IL-8 and IL-1β gene expressions. Lipopolysaccharide and hay dust solution treatments also resulted in a 7- and 8-fold increase in CXCL2 gene expression, respectively. The increases in IL-8 and CXCL2 gene expressions following treatment with the higher concentration of blood were equivalent to those associated with hay dust solution or lipopolysaccharide. Conclusions and Clinical Relevance: Results suggested that chemokine expression by cultured equine BECs following exposure to pulmonary hemorrhage conditions may contribute to the development of inflammatory airway disease in horses.
Mostrar más [+] Menos [-]Evaluation of a novel suture material for closure of intestinal anastomoses in canine cadavers
2012
Hansen, Lane A. | Monnet, Eric L.
Objective: To compare leakage and maximum intraluminal pressures for a novel suture material with pressures for comparable suture material when used in closure of intestinal anastomoses in canine cadavers. Sample: Healthy intestines from cadavers of dogs euthanized for reasons unrelated to the study. Procedures: 18 anastomoses were performed on intestinal sections within 72 hours after dogs were euthanized and intestinal samples collected. Anastomoses were performed with a simple continuous suture pattern. Leakage and maximum intraluminal pressures were measured and recorded for 6 control segments and 18 anastomosed sections. A barbed glycomer 631 suture (size 4–0 United States Pharmacopeia [USP]) was compared with glycomer 631 sutures (sizes 3–0 and 4–0 USP). Results for leakage and maximum intraluminal pressures were compared via an ANOVA. Results: The barbed glycomer 631 suture material leaked at a significantly higher pressure than did the comparable glycomer 631 suture materials. Maximum intraluminal pressures were not significantly different among the suture materials. Conclusions and Clinical Relevance: Barbed glycomer 631 4–0 USP suture material was as effective as glycomer 631 suture materials and may be a safe alternative for use in closure of enterectomies in dogs.
Mostrar más [+] Menos [-]Inactivation of the gene encoding zinc-binding lipoprotein 103 impairs the infectivity of Streptococcus suis
2012
Aranda, Jesus | Teixido, Laura | Fittipaldi, Nahuel | Cortés, Pilar | Llagostera, Montserrat | Gottschalk, Marcelo | Barbe, Jordi
The Streptococcus suis 103 gene product is an immunogenic and protective lipoprotein that is a component of an ATP-binding cassette transporter implicated in zinc uptake. Belonging to the same transcriptional unit and downstream of the 103 gene is a gene that encodes a homologue of the pneumococcal histidine triad (Pht) protein Pht309. In an intraperitoneal mouse model the virulence of a mutant lacking the 103 gene was more than 50 times lower than that of the wild-type (WT) parent strain, S. suis serotype 2 strain P1/7. In addition, the immunogenicity of this mutant was dramatically decreased. In striking contrast, the virulence and immunogenicity of a P1/7 mutant lacking the Pht309 gene were similar to those of the parent strain. These results demonstrate that the 103 lipoprotein is strongly involved in S. suis virulence and support the hypothesis that this lipoprotein might be an excellent candidate for vaccines aiming to achieve broad protection against streptococci.
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