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The presence of Ehrlichia canis in Rhipicephalus bursa ticks collected from ungulates in continental Eastern Europe
2021
Matei, Ioana Adriana | Ionică, Angela Monica | Corduneanu, Alexandra | Domșa, Cristian | Sándor, Attila D.
Rhipicephalus bursa is a common tick parasite of small-to-medium size ungulates, principally in warm, temperate, and subtropical areas. Although common in livestock and showing a wide geographic distribution, its epidemiological role in tick-borne bacterial disease is barely known. This study addressed the knowledge gap and aimed to screen for the presence of Anaplasmataceae and spotted fever group (SFG) Rickettsia species in R. bursa ticks collected from domestic animals in Romania, Eastern Europe. A total of 64 pools of R. bursa ticks collected from small ungulates were tested by PCR for Anaplasmataceae DNA presence using group-specific primers. Specific testing was performed for Anaplasma marginale/A. centrale/A. ovis, A. platys, A. phagocytophilum, Ehrlichia canis, and SFG Rickettsia. The positive samples were purified and sequenced, and sequences analysis was used to identify the species and to confirm the PCR results. The only pathogen identified in this study was E. canis. The obtained sequences confirmed the PCR results. The presence of E. canis in R. bursa in Romania and in ticks from sheep was shown for the first time in this study. Based on these findings, it may be presumed that the E. canis DNA originated from ticks; however, the vectorial role of R. bursa (and other arthropod species) in the transmission of E. canis should be proved experimentally.
اظهر المزيد [+] اقل [-]Cyclooxygenase-2 as a biomarker with diagnostic, therapeutic, prognostic, and predictive relevance in small animal oncology
2020
Szweda, Marta | Rychlik, Andrzej | Babińska, Izabella | Pomianowski, Andrzej
In canine and feline populations, the number of neoplasm cases continues to increase around the world. Attempts are being made in centres of research to identify new biomarkers that speed up and improve the quality of oncological diagnostics and therapy in human and animal tumour patients. Cyclooxygenase-2 (COX-2) is a promising biomarker with increasing relevance to human oncology, but as yet with less application in veterinary oncology. The expression of COX-2 increases significantly during pathological processes involving inflammation, pain or fever. It is also overexpressed in humans presenting various types of tumours and in selected types of tumours in animals, particularly in dogs. This article discusses the expression of COX-2 in canine and feline tumours, the importance of COX-2 as a biomarker with diagnostic, therapeutic, prognostic and predictive relevance in oncology, and the clinical significance of inhibiting COX-2 overexpression in tumours.
اظهر المزيد [+] اقل [-]Roles of African swine fever virus structural proteins in viral infection
2017
Jia, Ning | Ou, Yunwen | Pejsak, Zygmunt | Zhang, Yongguang | Zhang, Jie
African swine fever virus (ASFV) is a large, double-stranded DNA virus and the sole member of the Asfarviridae family. ASFV infects domestic pigs, wild boars, warthogs, and bush pigs, as well as soft ticks (Ornithodoros erraticus), which likely act as a vector. The major target is swine monocyte-macrophage cells. The virus can cause high fever, haemorrhagic lesions, cyanosis, anorexia, and even fatalities in domestic pigs. Currently, there is no vaccine and effective disease control strategies against its spread are culling infected pigs and maintaining high biosecurity standards. African swine fever (ASF) spread to Europe from Africa in the middle of the 20ᵗʰ century, and later also to South America and the Caribbean. Since then, ASF has spread more widely and thus is still a great challenge for swine breeding. The genome of ASFV ranges in length from about 170 to 193 kbp depending on the isolate and contains between 150 and 167 open reading frames (ORFs). The ASFV genome encodes 150 to 200 proteins, around 50 of them structural. The roles of virus structural proteins in viral infection have been described. These proteins, such as pp220, pp62, p72, p54, p30, and CD2v, serve as the major component of virus particles and have roles in attachment, entry, and replication. All studies on ASFV proteins lay a good foundation upon which to clarify the infection mechanism and develop vaccines and diagnosis methods. In this paper, the roles of ASFV structural proteins in viral infection are reviewed.
اظهر المزيد [+] اقل [-]Canine leishmaniasis prevalence in the Slovenian dog population
2021
Kotnik, Tina | Moreno Lázaro, Javier | Šoba, Barbara | Krt, Brane | Skvarč, Miha | Vergles Rataj, Aleksandra | Gorišek Bajc, Maja | Ravnik Verbič, Urša
Leishmaniasis is a life-threatening zoonosis of which dogs are the major reservoir and sandflies are the vectors. Until now, the prevalence of canine leishmaniasis (CanL) in the Slovenian dog population was unknown. Epidemiological data, eye swabs and blood samples were taken from 465 dogs born in Slovenia and older than one year. Commercial ELISA kits and real-time PCR were used. For ELISA-positive samples, an immunofluorescence antibody test (IFAT) was performed. Descriptive statistics were used to characterise the samples. The one-sample nonparametric chi-square test was used to test whether the categories of a variable were equally distributed. A 59.9% proportion of the recruited dogs had travelled to endemic regions and 62.1% of them had not been protected by insect repellents. Skin symptoms that might be CanL-related were described in 109 of the dogs’ histories (23.4%), inappetence and/or weight loss in 25 (5.4%), and anaemia, intermittent fever, and/or lymphadenopathy in 19 (4.1%). At the time of recruitment, all dogs were asymptomatic. All samples were PCR negative, nine (1.9%) were ELISA positive, but none were IFAT positive. Five of the nine ELISA-positive dogs were non-travellers. We conclude that the seroprevalence of canine leishmaniasis of 1.9 % in the autochthonous Slovenian dog population may pose a risk of endemic spread of the disease.
اظهر المزيد [+] اقل [-]Antioxidant status, and blood zinc and copper concentrations in dogs with uncomplicated babesiosis due to Babesia canis infections
2021
Teodorowski, Oliwier | Winiarczyk, Stanisław | Tarhan, Duygu | Dokuzeylül, Banu | Ercan, Alev Meltem | Or, Mehmet Erman | Staniec, Marta | Adaszek, Łukasz
The aim of the study was to demonstrate a link between uncomplicated Babesia canis infection in dogs and blood concentrations of zinc and copper and erythrocytic antioxidant defence – activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The study was based on 15 naturally occurring cases of canine babesiosis with anorexia, pyrexia, depression, pale mucous membrane, splenomegaly and dark red urine. Microscopic examination of Giemsa-stained peripheral blood smears and the results of PCR confirmed B. canis infection. Seven apparently healthy dogs brought in for either a check-up or vaccination were used for comparison. The levels of the erythrocytic antioxidant enzymes - SOD and CAT - were significantly higher in the infected dogs than in cytologically negative dogs. The levels of blood micronutrients were significantly lower in the infected dogs (0.478 μg of zinc per mL vs 1.241 μg/mL and 0.722 μg of copper per mL vs 1.392 μg/mL). Oxidative stress can be posited as one of the mechanisms leading to anaemia in dogs with babesiosis, and therefore antioxidant biomarker and copper and zinc concentrations could be used as indicators of disease severity and prognostic markers.
اظهر المزيد [+] اقل [-]Efficacy of the early administration of valacyclovir hydrochloride for the treatment of neuropathogenic equine herpesvirus type-1 infection in horses
2017
Maxwell, Lara K. | Bentz, Bradford G. | Gilliam, Lyndi L. | Ritchey, Jerry W. | Pusterla, Nicola | Holbrook, Todd C. | McFarlane, Dianne | Rezabek, Grant B. | Meinkoth, James | Whitfield, Chase | Goad, Carla L. | Allen, George P. | Eberle, R.
OBJECTIVE To determine whether prophylactic administration of valacyclovir hydrochloride versus initiation of treatment at the onset of fever would differentially protect horses from viral replication and clinical disease attributable to equine herpesvirus type-1 (EHV-1) infection. ANIMALS 18 aged mares. PROCEDURES Horses were randomly assigned to receive an oral placebo (control), treatment at detection of fever, or prophylactic treatment (initiated 1 day prior to viral challenge) and then inoculated intranasally with a neuropathogenic strain of EHV-1. Placebo or valacyclovir was administered orally for 7 or 14 days after EHV-1 inoculation or detection of fever (3 horses/group). Effects of treatment on viral replication and clinical disease were evaluated. Plasma acyclovir concentrations and viremia were assessed to determine inhibitory concentrations of valacyclovir. RESULTS Valacyclovir administration decreased shedding of virus and viremia, compared with findings for control horses. Rectal temperatures and clinical disease scores in horses that received valacyclovir prophylactically for 2 weeks were lower than those in control horses. The severity of but not the risk for ataxia was decreased by valacyclovir administration. Viremia was decreased when steady-state trough plasma acyclovir concentrations were > 0.8 μg/mL, supporting the time-dependent activity of acyclovir. CONCLUSIONS AND CLINICAL RELEVANCE Valacyclovir treatment significantly decreased viral replication and signs of disease in EHV-1–infected horses; effects were greatest when treatment was initiated before viral inoculation, but treatment was also effective when initiated as late as 2 days after inoculation. During an outbreak of equine herpesvirus myeloencephalopathy, antiviral treatment may be initiated in horses at various stages of infection, including horses that have not yet developed signs of viral disease.
اظهر المزيد [+] اقل [-]Effects of cleavage by a disintegrin and metalloproteinase with thrombospondin motifs-4 on gene expression and protein content of versican and aggrecan in the digital laminae of horses with starch gruel–induced laminitis
2012
Wang, Le | Pawlak, Erica | Johnson, Philip J. | Belknap, James K. | Alfandari, Dominique | Black, Samuel J.
Objective: To determine whether increased gene expression of a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4) in laminae of horses with starch gruel–induced laminitis was accompanied by increased enzyme activity and substrate degradation. Sample: Laminae from the forelimb hooves of 8 healthy horses and 17 horses with starch gruel–induced laminitis (6 at onset of fever, 6 at onset of Obel grade 1 lameness, and 5 at onset of Obel grade 3 lameness). Procedures: Gene expression was determined by use of cDNA and real-time quantitative PCR assay. Protein expression and processing were determined via SDS-PAGE and quantitative western blotting. Protein distribution and abundance were determined via quantitative immunofluorescent staining. Results: ADAMTS-4 gene expression was increased and that of versican decreased in laminitic laminae, compared with expression in healthy laminae. Catalytically active ADAMTS-4 also was increased in the tissue, as were ADAMTS-4–cleavage fragments of versican. Immunofluorescent analyses indicated that versican was depleted from the basal epithelia of laminae of horses at onset of Obel grade 3 lameness, compared with results for healthy laminae, and this was accompanied by regional separation of basal epithelial cells from the basement membrane. Aggrecan gene and protein expression were not significantly affected. Conclusions and Clinical Relevance: Changes in gene and protein expression of ADAMTS-4 and versican in the basal epithelium of laminitic laminae indicated a fundamental change in the physiology of basal epithelial cells. This was accompanied by and may have caused detachment of these cells from the basement membrane.
اظهر المزيد [+] اقل [-]Distribution of viral antigen and development of lesions after experimental infection with highly virulent bovine viral diarrhea virus type 2 in calves
2002
Liebler-Tenorio, Elisabeth M. | Ridpath, Julia F. | Neill, John D.
Objective-To correlate tissue distribution with development of lesions after experimental infection with a virulent strain of noncytopathic bovine viral diarrhea virus (BVDV) type 2 in calves. Animals-Ten 14-day-old and two 2-month-old colostrum-deprived calves. Procedure-Calves were intranasally inoculated with BVDV type-2 strain 1373 from an outbreak of clinically severe bovine viral diarrhea (BVD). Two 14-day-old calves served as noninfected controls. Two calves each were euthanatized on postinoculation days 3, 6, and 12, and 1 each on days 8, 9, 13, and 14. Tissues were collected for immunohistologic and histologic examination. Results-Inoculated calves developed nonspecific clinical signs characterized by high fever and decreased numbers of leukocytes and thrombocytes. Viral antigen was detected focally in lymphoid tissues on day 3. On days 6, 8, 9, 12, and 14, viral antigen became increasingly widespread throughout organs and tissues. Viral antigen in lymphoid tissues was associated with severe depletion of all compartments. Lesions in other tissues were not well correlated with distribution of viral antigen. Depletion of lymphoid tissues was observed in a calf on day 13, but viral antigen had been cleared from most tissues and was detected in vascular walls only. Conclusions and Clinical Relevance-Infection with a virulent BVDV strain resulted in wide dissemination of viral antigen in host tissues. Severe lymphoid depletion developed in lymphoid tissues, whereas viral antigen was generally not associated with lesions in other tissues. Findings suggest that development of lesions in acute BVD is not solely a function of viral replication and is also attributable to host reaction to infection.
اظهر المزيد [+] اقل [-]Modulation of thermal killing of bovine lymphocytes and preimplantation mouse embryos by alanine and taurine
1992
Malayer, J.R. | Pollard, J.W. | Hansen, P.J.
Addition of alanine and taurine blocked killing of lymphocytes caused by culture at 45 C. The optimal concentration for thermoprotection was achieved at 12.5 mM for L-alanine and 5 mM for taurine. Both D and L forms of alanine provided thermoprotection. The effect of these agents was not simply to increase osmolarity of the culture medium, because NaCl did not provide thermoprotection at comparable concentrations. Alanine and taurine were each tested at concentration of 50 mM for ability to block heat shock-induced killing and developmental retardation of 8- to 16-cell mouse embryos. Both agents enhanced embryo development after exposure to high temperature, though development remained less than that for embryos not exposed to high temperature. In one experiment, for example, 81% of embryos cultured at 38 C advanced in development during culture vs 0% at 42 C, 15% at 42 C with alanine, and 32% at 42 C with taurine. The beneficial effect of alanine at high temperature may have been partly attributable to effects independent of thermoprotection, because development of embryos cultured at 38 C was also improved by alanine.
اظهر المزيد [+] اقل [-]Effect of a passive heat and moisture exchanger on esophageal temperature in tumor-bearing dogs during whole-body hyperthermia
1991
Meyer, R.E. | Page, R.L. | Thrall, D.E.
The effect of a passive heat and moisture exchanger on tracheal and large airway temperature, as reflected by esophageal temperature at the thoracic inlet, was determined for 12 anesthetized and ventilated tumor-bearing dogs undergoing whole-body hyperthermia at 42 C. Delivered thermal dose to the esophagus and rectum during 120 minutes of whole-body hyperthermia was quantified as the thermal dose summary measure EQ43. The heat and moisture exchanger significantly increased esophageal EQ43 from 7.3 minutes to 12.1 minutes. Esophageal EQ43, however, remained lower than rectal EQ43. Although use of a heat and moisture exchanger improved esophageal temperature during whole-body hyperthermia, presumably through improved airway temperature, additional methods will be necessary to increase esophageal and airway temperature to the target value of 42 C.
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