Laboratory methods in equine research encompass a variety of techniques and procedures used to analyze biological samples from horses to study health, disease, genetics, and physiology. These methods include hematological analyses, biochemical assays, molecular biology techniques, and microbiological cultures. Commonly utilized laboratory techniques involve blood tests for complete blood count (CBC) and serum chemistry, polymerase chain reaction (PCR) for genetic and infectious disease studies, and enzyme-linked immunosorbent assays (ELISA) for detecting specific proteins or antibodies. These methods provide valuable data that contribute to understanding equine health and disease mechanisms. This page compiles peer-reviewed research studies and scholarly articles that explore the application, development, and outcomes of laboratory methods in the context of equine research.
Mackowski M, Kajdasz A, Laskowska K, Cieslak J.Although serological and genetic studies of equine blood group systems have been conducted for many years, the molecular basis of erythrocyte antigens' variability has remained largely unexplored. In this study, we aimed to elucidate the genetic basis of serological variation within equine blood group K. Using mRNA extracted from peripheral blood samples (n = 100) collected from horses with known serological blood types (Ka or K-), we performed a transcriptome-wide association study (TWAS), which revealed a significantly associated region on equine chromosome 2 (ECA2). A detailed analysis ...
Latorre N, Gómez-Cuétara C, Cañizares E, Crespo F, Pérez-Aguilera V, Cuerda MI, Laborda-Gomariz JA, Soler AJ, Roldan ERS, Sanchez-Rodriguez A.Evaluating semen quality in Purebred Spanish Horses is essential to determine reproductive potential and optimize assisted reproductive techniques. Objective: This study compared several sperm analysis methods in Purebred Spanish Horses to standardize protocols suitable for both laboratory and field conditions. Methods: Fifteen stallions were evaluated through three ejaculates, analyzing sperm parameters using different techniques. Sperm kinematics was assessed by Sperm Computer Analyzer (SCA-CASA) or iSperm mCASA. Viability was analyzed by eosin-nigrosin-Giemsa (ENG) staining or Hoechst 33258...
Wickizer LF, Burk SV, Lehman JS.Red maple toxicosis arises when horses consume wilted maple leaves, resulting in methemoglobinemia and hemolytic anemia due to oxidative damage to erythrocytes. Objective: The objective of this study was to determine how maple species (red versus Freeman maple) and horse characteristics, management, and barn site contributed to in vitro methemoglobin production and hemolysis. Methods: Horse information was obtained through an owner questionnaire. Extracts from red and Freeman maple leaves were separately incubated with washed erythrocytes from each horse (n=120). The in vitro percentage methem...
So YM, Kwok WH, Yuen SMS, Wong COL, Ho ENM.Despite the recent success in introducing supramolecular solvents (SUPRAS)-based extraction to drug analysis, its application and robustness in day-to-day regular urine testing have yet to be demonstrated. Moreover, the applicability of SUPRAS in equine doping control testing remains unexplored. In this work, we have successfully developed for the first time a simple, rapid, inexpensive, and environmentally friendly SUPRAS extraction method for analyzing 76 prohibited substances of different classes (selective androgen receptor modulators, hypoxia-inducible factor prolyl hydroxylase inhibitors...
Normélia P Morais A, Gastal GDA, Aguiar FLN, Hyde KA, Gastal MO, Lima LF, Ñaupas LVS, Flávia B Silva A, Becerra VAB, Gheno L, Curcio BR....Understanding how to effectively isolate a large number of healthy follicles is essential for increasing success rates in ARTs, such as in vitro culture and cryopreservation. Late secondary (preantral) and early tertiary (antral) follicles isolated from the intermediary portion of equine ovarian tissue sliced at two different thicknesses (0.25 mm vs. 0.50 mm) were characterized according to regional distribution (dorsal, medial, and ventral), morphofunctional features, and epigenetic profiles. After isolation via microdissection, follicles were evaluated for membrane integrity (trypan blue), v...
Fernández-Villa C, Miranda M, Rigueira L, Martinez L, Villanueva B, Freire S, López-Alonso M.Serum mineral concentrations are key indicators of nutritional status, metabolic function and health in horses; however, contemporary reference intervals (RI) derived from large, well-characterised populations remain scarce. Objective: To establish serum RI for macro- and microminerals in clinically healthy horses in Northwestern Spain and to evaluate the influence of sex, age, breed and diet on mineral status. Methods: Blood samples were collected from clinically healthy horses (n = 211), and serum concentrations of essential macrominerals (calcium [Ca]; phosphorous [P]; magnesium [Mg]; sodiu...
Enkhtuul B, Khurtsbaatar O, Lkham B, Agiimaa T, Unenbat J, Buyanbadrakh B, Ninjbulgan S, Liushiqi B, Suzuki Y, Kimura T, Batbaatar V.Glanders, a zoonotic disease caused by , has re-emerged in Mongolia after decades of control. We conducted nationwide serosurveillance from 2021 to 2024 to assess the prevalence and geographic distribution of glanders. Using random 3-stage cluster sampling, we collected 3,001 horse serum samples from 332 herds. Those herds were in 46 soums (administrative districts equivalent to counties) in 13 provinces and in 3 districts in Ulaanbaatar. Sera were tested using the complement fixation test, and positive results were confirmed by immunoblotting and ELISA. Overall seroprevalence was 1.03% (95% C...
Bindi F, de Marchi L, Elias-Cortajarena A, Sala G, Vitale V, Spadari A, Rinnovati R, Bonelli F, Sgorbini M.Colic is a major cause of morbidity and mortality in horses, with oxidative stress implicated in its pathophysiology. Objective: Evaluate biomarkers (BIOs) of oxidative stress and antioxidant defense in healthy horses and those with non-strangulating colic (NSC) and strangulating colic (SC) and assess correlations with survival. Methods: Seventy-one adult horses: 10 healthy and 61 colic-affected (42 NSC, 19 SC) admitted to 3 veterinary teaching hospitals. Methods: Prospective, multicenter cohort study. Blood samples were collected at admission (T0) and up to 96 h post-admission. Biomarkers me...
The ability of spermatozoa to withstand cryopreservation differs between stallions. While the underlying mechanisms of these differences are not fully understood, seminal plasma (SP) may play a crucial role in modulating sperm cryotolerance. Seminal plasma contains a heterogeneous population of extracellular vesicles (sEVs), nanometer-sized membrane particles that can transfer biomolecules to sperm modulating their function. This study aimed to isolate and characterize two sized-sEV subsets-small (S-) and large (L-)-from stallion SP, and to evaluate their involvement in sperm freezability. Sem...
Granello ME, Young JM, Cleff DB, Banks EBM, Trumble TN.To describe characteristics of postoperative peritoneal fluid following exploratory laparotomy for naturally-occurring gastrointestinal lesions in horses. Methods: Prospective, observational cohort study. Methods: A total of 26 client-owned horses that underwent exploratory laparotomy for naturally-occurring gastrointestinal lesions. Methods: Abdominocentesis was performed pre- or intraoperatively, and at three time points postoperatively (24, 72, and 168 h). Peritoneal lactate, total protein (TP), total nucleated cell count (TNCC), cytology, and systemic lactate were performed at each time ...
Tsopp E, Kilk K, Gambini A, Tvrdà E, Viljaste-Seera A, Tuppits U, Jaakma Ü.Equine in vitro embryo production (IVP) via ovum pick-up (OPU) and intracytoplasmic sperm injection (ICSI) has gained prominence in sport-horse breeding due to high success rates, efficient semen utilization, and year-round embryo production, including from mares with fertility challenges or postmortem. However, assessing viability of early-stage ICSI-produced equine embryos remains challenging due to subjective morphological evaluations and limited visibility of developmental features. Non-invasive metabolomic analysis of culture media offers a promising alternative to enhance embryo selectio...
Aliani C, Lorenzetto Bologna C, Francia P, Bocchi L.Standing equine computed tomography (CT) acquisitions are susceptible to residual postural sway, which can introduce view-inconsistent motion and degrade image quality. External optical tracking based on ChArUco fiducials is a promising, low-cost strategy to enable projection-wise motion compensation, yet quantitative guidance on how camera-marker geometry affects pose-estimation performance remains limited. This CT-motivated benchtop study characterizes how the relative camera-ChArUco configuration influences both the accuracy (bias with respect to ground truth) and the precision (repeatabili...
Díaz-Alvarado T, Alcala-Canto Y, Elghandour MMMY, Salem MZM, Mariezcurrena-Berasain MD, Salem AZM.Gastrointestinal endoparasitic diseases, particularly those caused by some strongyles, represent one of the main health challenges in equine production. The prolonged use of synthetic anthelmintics has led to the development of resistance, which has prompted the search for more sustainable therapeutic alternatives. However, plant extracts rich in secondary metabolites are emerging as a promising option. Objective: The objective of this study was to evaluate the in vitro anthelmintic activity of aqueous extracts and bioactive compounds (total phenols and saponins) from Azadirachta indica and Cn...
Gentilini F, Ogundipe TG, Turba ME, Romagnoli N, Lambertini C, Pollera C, Cremonesi P, Stancampiano L.Gastrointestinal nematode infections significantly impact equine health and welfare, with rising anthelmintic resistance demanding alternative control strategies. Emerging evidence suggests that parasitic nematodes harbour distinct microbiomes, potentially influencing host-parasite dynamics and parasite survival. This study aimed to characterize and compare the microbiomes of equine gastrointestinal nematodes and their hosts, focusing on differences in composition, diversity, and core microbiota structure across different intestinal sites, nematode subfamilies, and sexes. Faecal and nematode s...
Penzhorn L, Crafford JE, Guthrie AJ.African horse sickness (AHS) is the only equine disease for which the World Organisation for Animal Health (WOAH) gives official disease-free status, given that it poses a major threat to the equine industry. The disease is caused by AHS virus (AHSV; family , taxon species ), which is endemic in sub-Saharan Africa. Reverse-transcription quantitative real-time PCR (RT-qPCR) is a rapid, sensitive detection method used in the diagnosis of AHS and the certification of animals as negative for AHSV for the purpose of movement. Genetic variability of AHSV may influence the accuracy of RT-qPCR detecti...
Cortez JV, Cervi D, Ruiz AJ, Grupen CG.Nicotinic acid (NA) treatment during in vitro maturation (IVM) has been shown to elevate nicotinamide adenine dinucleotide (NAD) levels and improve oocyte developmental competence. Suboptimal equine oocyte IVM systems currently limit the efficiency of viable embryo in vitro production. This study evaluated NA supplementation during IVM for cloned equine embryo production, using oocytes from abattoir-sourced ovaries and live mares via ovum pick-up (OPU). Abattoir-derived oocytes (n = 694) were treated without or with 50 or 200 μM NA during the 18 h holding period (Pre-IVM). Next, OPU-deriv...
Meistro F, Rinnovati R, Blanc E, Berni P, Napoli S, Marcucci E, D'Angelo P, Ruggeri M, Spadari A, Gialletti R.Accurate early prognostic assessment is a central aspect of clinical decision-making in horses presenting with colic. Despite the availability of multiple clinical and laboratory parameters, reliable biomarkers that provide useful information at the time of admission remain limited. The erythrocyte sedimentation rate is a non-specific indicator of systemic inflammation that has recently been validated for automated point-of-care use in horses. Its behaviour in equine colic has not been previously characterised. This study included 85 horses admitted for colic at two university referral hospita...
Palomino Lago E, Roberts SJ, Orriss IR, Lumsden ES, Guest DJ.Bone is a dynamic tissue that is maintained through the co-ordination of bone resorption and bone formation. An imbalance of these processes can lead to bone disease. In vitro studies of osteoblasts can help to understand bone formation, but primary cells have a limited lifespan in culture. Herein, we report the successful generation of equine immortalized osteoblasts through the stable overexpression of human telomerase reverse transcriptase (hTERT) and Simian virus 40 (SV40) large T-antigen in osteoblasts isolated from trabecular bone taken from the third metacarpal of a two-year-old Thoroug...
Carotenuto SE, Broussard G, Fox GA, Hayes WK.To assess the efficacy of a new equine F[ab'] antivenom (US Department of Agriculture code 6101.05) in removing serum venom and lowering the snakebite severity score (SSS) in animals suffering from naturally occurring viperid envenomation. Methods: Retrospective study, April 2020 to October 2021. Methods: Veterinary hospitals across four North American regions. Methods: Twenty-two dogs, one cat, and one horse. Methods: All patients received the new antivenom intravenously and were assessed for clinical response. Most dogs required one vial for clinical control of signs. Results: Among the dogs...
Bindi F, Cingottini D, Sorvillo B, Sala G, De Marchi L, Monni G, Celardo S, Bonelli F, Sgorbini M.During the perinatal period, neonates experience a sudden increase in oxygen exposure, predisposing them to oxidative stress. Objective: This prospective, in vivo study aimed to evaluate biomarkers of oxidative stress and antioxidant defence in healthy neonatal foals during the first 48 hours of life. Methods: Ten Standardbred foals were enrolled. Blood samples were collected at birth, 24 hours, and 48 hours after birth and analyzed for biomarkers using spectrophotometry assays. Statistical analysis was performed using non-parametric tests and linear regression. Results: The results revealed s...
Milczek-Haduch D, Żmigrodzka M, Kiełbik P, Świderska B, Olędzki J, Witkowska-Piłaszewicz O.Extracellular vesicles (EVs) are promising biomarkers and mediators of intercellular communication, but their isolation from equine biofluids remains challenging. This study compared two isolation workflows-size-exclusion chromatography (SEC) and differential ultracentrifugation followed by SEC (UC + SEC)-to evaluate their efficiency, reproducibility, and the proteomic composition of EVs derived from equine serum and plasma. Blood from six healthy horses was processed to obtain platelet-free plasma and serum. EVs were isolated using SEC or UC + SEC and characterized by transmission ele...
So YM, Kwok WH, Yap C, Wong COL, Smalley SGR, Forbes BS, Chow DWY, Ho ENM.This paper describes the detection and longitudinal monitoring of cyclosporine in plasma and urine after subconjunctival implant administration in a horse. Sensitive liquid chromatography tandem mass spectroscopy (LC-MS/MS) methods for detecting cyclosporine in horse plasma and urine have been developed and validated, with estimated limits of detection down to 1 pg/mL in both matrices. The developed methods enabled longitudinal monitoring of cyclosporine levels in blood and urine samples collected over 6 months from a horse that had received an ocular cyclosporine implant.
Pasicka E, Baca M, Popović D, Makowiecki D, Janeczek M.This study presents the sequencing and analysis of mitochondrial DNA (mtDNA) genomes from nine early medieval horse remains excavated across archaeological sites in Silesia region in present day Poland. Methods: Using aDNA extraction protocols optimized for short fragments, combined with target enrichment and high-throughput sequencing, we reconstructed partial mtDNA sequences for seven of the specimens. Results: The authenticity of the aDNA was confirmed through damage pattern analysis. Phylogenetic reconstruction revealed that the specimens belonged to six distinct mtDNA lineages (B, D, E, G...
Friend MM, McGaffigan EM, Hall SM, Staniar WB, Smarsh DN.Equine blood samples are often collected in uncontrolled, distant environments and stored for later analysis. Objective: This study aimed to determine how sample storage methods influence complete blood count (CBC) parameters, hypothesizing that temperature and time elapsed from collection to analysis would affect CBC parameters. Methods: Blood samples were collected from 10 healthy Quarter Horse mares (age: 13 ± 4.5 years old) and stored in EDTA tubes at room temperature (22°C), above ice (8°C), refrigerated (4°C), or in contact with ice (2°C). The IDEXX ProcyteDx was used to obtain CBCs...
Richardson LM, Gordon J, Davila C, Chamoun-Emanuelli AM, Zdyrski C, Whitfield-Cargile CM.Gastrointestinal (GI) disease is a major cause of morbidity and mortality in horses, with disruption of the intestinal epithelial barrier playing a central role in disease pathogenesis. A deeper understanding of the molecular and functional properties of the equine intestinal barrier is essential to improve diagnostics and therapeutics. While intestinal organoids have emerged as a promising tool for modeling GI physiology and disease, equine-specific data remain limited. Existing studies vary in methodology and often lack functional characterization, particularly across different intestinal re...
Thieulent CJ, Sarkar S, Carossino M, Bhowmik M, Zhu H, Balasuriya UBR.Our laboratory identified the susceptible allelic variant of equine CXCL16 protein (EqCXCL16S) as an entry receptor for equine arteritis virus (EAV). However, EAV has a broad host cell tropism and infects cells that lack EqCXCL16S. Thus, we hypothesized that EAV interacts with other host cell protein(s) that facilitate EAV infection. A virus overlay protein-binding assay in combination with a Far-Western blot from EAV-susceptible equine pulmonary artery endothelial cells (EECs) and equine dermal fibroblasts (E. Derm) identified a 57 kDa protein, present in the membrane fraction of the protein ...
Beniwal N, Lal B, Mithina S, Verma CK, Kumar S, Phagna V, Jakhar K, Sonar S, Gupta V, Singh R, Kumar N, Tan CW, Thachamvally R, Singha H, Murzello K....Rabies is a neglected tropical zoonotic disease caused by rabies-virus (RV) infection and is responsible for almost 60,000 annual deaths globally, largely affecting the socio-economically disadvantaged population. Although fatality is preventable by immunization either before or after exposure with therapeutic antibodies, the high cost of prophylaxis or treatment limits their accessibility for the affected population. However, due to the almost 100% fatality rate in symptomatic individuals, almost 29 million annual vaccinations are performed, imposing high financial burden. Human transmission ...
Ventura Lopes Carvalho B, Neves de Souza MC, Souza Moreira N, Parisi Marliere J, Mesquita Mota JV, Drumond Bento L, de Castro Benitez A, Avanza MFB....Two routes of administration for electrolyte solutions are commonly used in horses with fluid, electrolyte, and acid-base imbalances: intravenous and nasogastric. Despite the frequent use of these routes, there are situations in which they cannot be applied. In such cases, intracecal fluid therapy represents a viable alternative, as this route enables the administration of enteral electrolyte solutions even in animals lacking normal anterior gastrointestinal function. This study aimed to evaluate the effects of a neutral hypotonic enteral electrolyte solution administered intracecally at two d...
Varela V, Costa M, Maciel C, Barbeito J, Barrera EE, Gutierre E, Correa A, Elgue M, Carrasco S, Larrosa MD, Pereira M, Correa J, Crosignani N....Anti-NGF monoclonal antibodies have recently been approved for treating degenerative joint disease, including osteoarthritis pain, in dogs and cats. However, their widespread use is limited by high cost and the requirement for repeated injections. Nerve Growth Factor and Substance P play central roles in the initiation and maintenance of inflammation and chronic pain in OA. There is a pressing need for new, safe, cost-effective therapies that target the underlying mechanisms of OA chronic pain. Here, we designed and produced a novel recombinant fusion protein, termed rNGFSP, which functions as...
Kirmse L, Thieme K, Doherr MG, Eule JC.To evaluate different laboratory procedures for determining the etiologic diagnosis of equine recurrent uveitis regarding intraocular infection with Leptospira spp. and to establish a diagnostic guideline. Methods: Eighty horses with a history of ERU were ophthalmologically examined. Serum and aqueous humor were collected. Total protein, albumin level, and MAT against Leptospira spp. were evaluated on serum and aqueous humor. PCR for Leptospira spp., EHV-1 and -4 was performed on aqueous humor. Goldmann-Witmer coefficient (GWC) and C-value (CC) were calculated based on MAT. In 42 cases, an add...
Coles GC, Bauer C, Borgsteede FH, Geerts S, Klei TR, Taylor MA, Waller PJ.Methods have been described to assist in the detection of anthelmintic resistance in strongylid nematodes of ruminants, horses and pigs. Two tests are recommended, an in vivo test, the faecal egg count reduction test for use in infected animals, and an in vitro test, the egg hatch test for detection of benzimidazole resistance in nematodes that hatch shortly after embryonation. Anaerobic storage for submission of faecal samples from the field for use in the in vitro test is of value and the procedure is described. The tests should enable comparable data to be obtained in surveys in all parts o...
Coles GC, Jackson F, Pomroy WE, Prichard RK, von Samson-Himmelstjerna G, Silvestre A, Taylor MA, Vercruysse J.Before revised World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines on the detection of anthelmintic resistance can be produced, validation of modified and new methods is required in laboratories in different parts of the world. There is a great need for improved methods of detection of anthelmintic resistance particularly for the detection of macrocyclic lactone resistance and for the detection of resistant nematodes in cattle. Therefore, revised and new methods are provided here for the detection of anthelmintic resistance in nematodes of ruminants, horses and ...
Gelderblom WC, Jaskiewicz K, Marasas WF, Thiel PG, Horak RM, Vleggaar R, Kriek NP.Cultures on corn of Fusarium moniliforme MRC 826 are known to cause leukoencephalomalacia in horses and to be toxic and hepatocarcinogenic in rats. Culture material of this F. moniliforme isolate has also been shown to exhibit cancer-promoting activity in a short-term cancer initiation-promotion bioassay with diethylnitrosamine-initiated rats and the induction of gamma-glutamyl-transpeptidase-positive (GGT+) foci as an endpoint after 4 weeks of promotion. This bioassay was used as a monitoring system to isolate cancer-promoting compounds from cultures of F. moniliforme MRC 826. Culture materia...
den Boon JA, Snijder EJ, Chirnside ED, de Vries AA, Horzinek MC, Spaan WJ.The nucleotide sequence of the genome of equine arteritis virus (EAV) was determined from a set of overlapping cDNA clones and was found to contain eight open reading frames (ORFs). ORFs 2 through 7 are expressed from six 3'-coterminal subgenomic mRNAs, which are transcribed from the 3'-terminal quarter of the viral genome. A number of these ORFs are predicted to encode structural EAV proteins. The organization and expression of the 3' part of the EAV genome are remarkably similar to those of coronaviruses and toroviruses. The 5'-terminal three-quarters of the genome contain the putative EAV p...
Bujacz A.Serum albumin first appeared in early vertebrates and is present in the plasma of all mammals. Its canonical structure supported by a conserved set of disulfide bridges is maintained in all mammalian serum albumins and any changes in sequence are highly correlated with evolution of the species. Previous structural investigations of mammalian serum albumins have only concentrated on human serum albumin (HSA), most likely as a consequence of crystallization and diffraction difficulties. Here, the crystal structures of serum albumins isolated from bovine, equine and leporine blood plasma are repo...
Quinlivan M, Zamarin D, García-Sastre A, Cullinane A, Chambers T, Palese P.Equine influenza is a common disease of the horse, causing significant morbidity worldwide. Here we describe the establishment of a plasmid-based reverse genetics system for equine influenza virus. Utilizing this system, we generated three mutant viruses encoding carboxy-terminally truncated NS1 proteins. We have previously shown that a recombinant human influenza virus lacking the NS1 gene (delNS1) could only replicate in interferon (IFN)-incompetent systems, suggesting that the NS1 protein is responsible for IFN antagonist activity. Contrary to previous findings with human influenza virus, w...
Puffer BA, Parent LJ, Wills JW, Montelaro RC.We have previously demonstrated that the Gag p9 protein of equine infectious anemia virus (EIAV) is functionally homologous with Rous sarcoma virus (RSV) p2b and human immunodeficiency virus type 1 (HIV-1) p6 in providing a critical late assembly function in RSV Gag-mediated budding from transfected COS-1 cells (L. J. Parent et al., J. Virol. 69:5455-5460, 1995). In light of the absence of amino acid sequence homology between EIAV p9 and the functional homologs of RSV and HIV-1, we have now designed an EIAV Gag-mediated budding assay to define the late assembly (L) domain peptide sequences con...
Science (New York, N.Y.)December 11, 1992
Volume 258, Issue 5089 1748-1755 doi: 10.1126/science.1334573
Pelletier H, Kraut J.The crystal structure of a 1:1 complex between yeast cytochrome c peroxidase and yeast iso-1-cytochrome c was determined at 2.3 A resolution. This structure reveals a possible electron transfer pathway unlike any previously proposed for this extensively studied redox pair. The shortest straight line between the two hemes closely follows the peroxidase backbone chain of residues Ala194, Ala193, Gly192, and finally Trp191, the indole ring of which is perpendicular to, and in van der Waals contact with, the peroxidase heme. The crystal structure at 2.8 A of a complex between yeast cytochrome c pe...
Ito S, Wakamatsu K.The color of hair, skin, and eyes in animals mainly depends on the quantity, quality, and distribution of the pigment melanin, which occurs in two types: black to brown eumelanin and yellow to reddish pheomelanin. Microanalytical methods to quantify the amounts of eumelanin and pheomelanin in biological materials were developed in 1985. The methods are based on the chemical degradation of eumelanin to pyrrole-2,3,5-tricarboxylic acid and of pheomelanin to aminohydroxyphenylalanine isomers, which can be analyzed and quantitated by high performance liquid chromatography. This review summarizes a...
Burbelo PD, Dubovi EJ, Simmonds P, Medina JL, Henriquez JA, Mishra N, Wagner J, Tokarz R, Cullen JM, Iadarola MJ, Rice CM, Lipkin WI, Kapoor A.Genetic and biological characterization of new hepaciviruses infecting animals contributes to our understanding of the ultimate origins of hepatitis C virus (HCV) infection in humans and dramatically enhances our ability to study its pathogenesis using tractable animal models. Animal homologs of HCV include a recently discovered canine hepacivirus (CHV) and GB virus B (GBV-B), both viruses with largely undetermined natural host ranges. Here we used a versatile serology-based approach to determine the natural host of the only known nonprimate hepacivirus (NPHV), CHV, which is also the closest p...
Calisher CH.Of more than 500 arboviruses recognized worldwide, 5 were first isolated in Canada and 58 were first isolated in the United States. Six of these viruses are human pathogens: western equine encephalitis (WEE) and eastern equine encephalitis (EEE) viruses (family Togaviridae, genus Alphavirus), St. Louis encephalitis (SLE) and Powassan (POW) viruses (Flaviviridae, Flavivirus), LaCrosse (LAC) virus (Bunyaviridae, Bunyavirus), and Colorado tick fever (CTF) virus (Reoviridae, Coltivirus). Their scientific histories, geographic distributions, virology, epidemiology, vectors, vertebrate hosts, transm...
Higuchi R, Bowman B, Freiberger M, Ryder OA, Wilson AC.To determine whether DNA survives and can be recovered from the remains of extinct creatures, we have examined dried muscle from a museum specimen of the quagga, a zebra-like species (Equus quagga) that became extinct in 1883 (ref. 1). We report that DNA was extracted from this tissue in amounts approaching 1% of that expected from fresh muscle, and that the DNA was of relatively low molecular weight. Among the many clones obtained from the quagga DNA, two containing pieces of mitochondrial DNA (mtDNA) were sequenced. These sequences, comprising 229 nucleotide pairs, differ by 12 base substitu...
Kalbfleisch TS, Rice ES, DePriest MS, Walenz BP, Hestand MS, Vermeesch JR, O Connell BL, Fiddes IT, Vershinina AO, Saremi NF, Petersen JL, Finno CJ....Recent advances in genomic sequencing technology and computational assembly methods have allowed scientists to improve reference genome assemblies in terms of contiguity and composition. EquCab2, a reference genome for the domestic horse, was released in 2007. Although of equal or better quality compared to other first-generation Sanger assemblies, it had many of the shortcomings common to them. In 2014, the equine genomics research community began a project to improve the reference sequence for the horse, building upon the solid foundation of EquCab2 and incorporating new short-read data, lon...
MacDonald GH, Johnston RE.The initial steps of Venezuelan equine encephalitis virus (VEE) spread from inoculation in the skin to the draining lymph node have been characterized. By using green fluorescent protein and immunocytochemistry, dendritic cells in the draining lymph node were determined to be the primary target of VEE infection in the first 48 h following inoculation. VEE viral replicon particles, which can undergo only one round of infection, identified Langerhans cells to be the initial set of cells infected by VEE directly following inoculation. These cells are resident dendritic cells in the skin, which mi...
Schwartz S, Elnitski L, Li M, Weirauch M, Riemer C, Smit A, Green ED, Hardison RC, Miller W.Analysis of multiple sequence alignments can generate important, testable hypotheses about the phylogenetic history and cellular function of genomic sequences. We describe the MultiPipMaker server, which aligns multiple, long genomic DNA sequences quickly and with good sensitivity (available at http://bio.cse.psu.edu/ since May 2001). Alignments are computed between a contiguous reference sequence and one or more secondary sequences, which can be finished or draft sequence. The outputs include a stacked set of percent identity plots, called a MultiPip, comparing the reference sequence with sub...
Schnabel LV, Mohammed HO, Miller BJ, McDermott WG, Jacobson MS, Santangelo KS, Fortier LA.Platelet rich plasma (PRP) has recently been investigated for use in tissue regeneration studies that seek to utilize the numerous growth factors released from platelet alpha-granules. This study examined gene expression patterns, DNA, and collagen content of equine flexor digitorum superficialis tendon (SDFT) explants cultured in media consisting of PRP and other blood products. Blood and bone marrow aspirate (BMA) were collected from horses and processed to obtain plasma, PRP, and platelet poor plasma (PPP). IGF-I, TGF-beta1, and PDGF-BB were quantified in all blood products using ELISA. Ten...
van Dinten LC, den Boon JA, Wassenaar AL, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV) is a positive-strand RNA virus that uses a discontinuous transcription mechanism to generate a nested set of six subgenomic mRNAs from which its structural genes are expressed. A stable bacterial plasmid (pEAV030) containing a full-length cDNA copy of the 12.7-kb EAV genome was constructed. After removal of a single point mutation in the replicase gene, RNA transcripts generated in vitro from pEAV030 were shown to be infectious upon electroporation into BHK-21 cells. A genetic marker mutation was introduced at the cDNA level and recovered from the genome of the pro...
Durham AE, Frank N, McGowan CM, Menzies-Gow NJ, Roelfsema E, Vervuert I, Feige K, Fey K.Equine metabolic syndrome (EMS) is a widely recognized collection of risk factors for endocrinopathic laminitis. The most important of these risk factors is insulin dysregulation (ID). Clinicians and horse owners must recognize the presence of these risk factors so that they can be targeted and controlled to reduce the risk of laminitis attacks. Diagnosis of EMS is based partly on the horse's history and clinical examination findings, and partly on laboratory testing. Several choices of test exist which examine different facets of ID and other related metabolic disturbances. EMS is controlled ...
de Vries AA, Chirnside ED, Horzinek MC, Rottier PJ.We have recently shown that the genome of equine arteritis virus (EAV) contains seven open reading frames (ORFs). We now present data on the structural proteins of EAV and the assignment of their respective genes. Virions are composed of a 14-kDa nucleocapsid protein (N) and three membrane proteins designated M, GS, and GL. M is an unglycosylated protein of 16 kDa, and GS and GL are N-glycosylated proteins of 25 and 30 to 42 kDa, respectively. The broad size distribution of GL results from heterogeneous N-acetyllactosamine addition since it is susceptible to digestion by endo-beta-galactosidas...
Nagase N, Sasaki A, Yamashita K, Shimizu A, Wakita Y, Kitai S, Kawano J.From April 1999 to December 2000, a survey was made on the distribution of Staphylococcus species on the skin of 7 kinds of animals and humans. Staphylococci were isolated from 12 (100%) of 12 pigs, 17 (89.5%) of 19 horses, 30 (100%) of 30 cows, 73 (90.1%) of 81 chickens, 10 (40%) of 25 dogs, 23 (76.7%) of 30 laboratory mice, 20 (52.6%) of 38 pigeons, and 80 (88.9%) of 90 human beings. The predominant staphylococci isolated from a variety of animal species were novobiocin-resistant species, S. xylosus and S. sciuri regardless of the animal host species. The novobiocin-resistant species includi...
Barlough JE, Madigan JE, DeRock E, Bigornia L.A nested polymerase chain reaction for detecting Ehrlichia equi in horses and ticks (Ixodes pacificus) was developed. A major second-round PCR product of 928 bp could be readily visualized in ethidium bromide-stained agarose minigels. An internal probe was used to verify the identity of the amplified product by non-radioactive (digoxigenin-based) Southern blotting; additional confirmation was provided by DNA sequence analysis. A dilution study testing the sensitivity of the PCR indicated that DNA derived from 3 infected neutrophils was sufficient to generate a PCR signal. The specificity of t...
Snijder EJ, Wassenaar AL, Spaan WJ.To study the proteolytic processing of the equine arteritis virus (EAV) replicase open reading frame 1a (ORF1a) protein, specific antisera were raised in rabbits, with six synthetic peptides and a bacterial fusion protein as antigens. The processing of the EAV ORF1a product in infected cells was analyzed with Western blot (immunoblot) and immunoprecipitation techniques. Additional information was obtained from transient expression of ORF1a cDNA constructs. The 187-kDa ORF1a protein was found to be subject to at least five proteolytic cleavages. The processing scheme, which covers the entire OR...
Chindera K, Mahato M, Sharma AK, Horsley H, Kloc-Muniak K, Kamaruzzaman NF, Kumar S, McFarlane A, Stach J, Bentin T, Good L.To combat infection and antimicrobial resistance, it is helpful to elucidate drug mechanism(s) of action. Here we examined how the widely used antimicrobial polyhexamethylene biguanide (PHMB) kills bacteria selectively over host cells. Contrary to the accepted model of microbial membrane disruption by PHMB, we observed cell entry into a range of bacterial species, and treated bacteria displayed cell division arrest and chromosome condensation, suggesting DNA binding as an alternative antimicrobial mechanism. A DNA-level mechanism was confirmed by observations that PHMB formed nanoparticles whe...
Xu X, Arnason U.The sequence of the mitochondrial (mt) DNA of the horse (Equus caballus) was determined. The length of the sequence presented is 16,660 bp. This figure, however, is not absolute due to pronounced heteroplasmy caused by variable numbers of the motif GTGCACCT in the control region of different molecules. Boundaries of the 13 peptide-coding genes were determined by the presence of start and stop codons, and by analogy with other eutherian mtDNAs. Three genes (COIII, NADH3 and NADH4) were not terminated by a stop codon. Comparison among the peptide-coding genes of the horse and eight other mammals...