Microbiology and horses explores the interactions between microorganisms and equine hosts, focusing on the role of bacteria, viruses, fungi, and other microbes in horse health and disease. This field examines the microbial flora present in various equine environments, including the gastrointestinal tract, skin, and respiratory system, and investigates how these microorganisms influence equine physiology and pathology. Research in this area includes studies on microbial infections that affect horses, the development of antimicrobial resistance, and the impact of probiotics and prebiotics on equine health. This page compiles peer-reviewed research studies and scholarly articles that investigate the diversity, dynamics, and implications of microbial communities in horses, as well as the strategies for managing microbial-related diseases.
McDaniel TK, Dewalt KC, Salama NR, Falkow S.Because of limited genetic tools for use in Helicobacter pylori, tests routinely applied in other bacteria for demonstrating a gene's role in viability and other phenotypes have not been applied to this organism. In a mutational study of putative response regulator genes, we aimed to develop such tools for H. pylori. Methods: We attempted to mutate five response regulator genes by allelic exchange insertional mutagenesis. For genes that yielded no viable mutants, a second copy of the gene was inserted into the chromosome via a suicide vector, and it was seen if providing the second copy would ...
Bonenberger TE, Ihrke PJ, Naydan DK, Affolter VK.Immunostaining with polyclonal anti-Mycobacterium bovis (BCG) was evaluated as a single screening method for the histological identification of micro-organisms in skin biopsy specimens from various veterinary species. Confirmed archival cases infected with Mycobacteria, Nocardia, Actinobacillus, Actinomyces, Streptococcus/Staphylococcus, Dermatophilus, spirochetes, Blastomyces, Coccidioides, Cryptococcus, Histoplasma, dermatophytes, Malassezia, Sporothrix, Leishmania, Pythium, phaeohyphomycetes and Prototheca organisms were selected. A total of 70 skin biopsy specimens from the dog, cat, horse...
Sellon DC, Besser TE, Vivrette SL, McConnico RS.Recently, a technique was described for amplification of Rhodococcus equi-specific chromosomal and vapA DNA from blood and tracheal wash fluids. It was hypothesized that this technique would be more sensitive than standard culture techniques or serology for diagnosis of R. equi pneumonia in foals. Tracheal wash fluid, nasal swabs, whole blood samples, and serum samples from 56 foals with pneumonia were analyzed. Final clinical diagnosis was determined by the attending clinician on the basis of final interpretation of all available information about each foal, including clinical presentation, d...
Takai S, Ogawa K, Fukunaga N, Sasaki Y, Kakuda T, Tsubaki S, Anzai T.R. equi was isolated from soil samples obtained from the environment of seven native Japanese horse breeds (Hokkaido, Kiso, Noma, Misaki, Tokara, Miyako and Yonaguni) and from fecal samples collected from three native horse breeds (Hokkaido, Kiso and Misaki). Virulent R. equi at various levels (ranging from 0.5 to 12.9%) was isolated from the feces or soil environment of Hokkaido, Kiso and Misaki horses. Isolates were investigated both for the presence of 15- to 17-kDa antigens (virulence-associated protein antigens; VapA) by colony blotting, using the monoclonal antibody 10G5, and the gene of...
Marsh AE, Mullins AL, Lakritz J.Parasite-specific incorporation of (3)H-uracil was used to assess the replication of Sarcocystis neurona, a protozoal parasite associated with equine protozoal myeloencephalitis (EPM). Anti-protozoal drugs, pyrimethamine (0.01, 0.1 and 1.0microg/ml PYR), sulfadiazine (5microg/ml; SDZ), sulfamethoxazole (5microg/ml; SMZ), diclazuril (100ng/ml; DCZ), atovaquone (0.04ng/ml; ATQ), tetracycline (5microg/ml; TET) and the herbicide glyphosate (1.5 and 4.5mM; GLY) were studied with varying S. neurona parasite densities (2x10(1)-1.2x10(6)merozoites/well). A microtiter plate format was used to test thes...
Dabareiner RM, White NA, Donaldson LL.To determine whether intraluminal distention and subsequent decompression of the equine jejunum affects intestinal blood flow, hemodynamics, and microvascular permeability. Methods: 5 healthy adu t horses. Methods: Horses were anesthestized and underwent exploratory laparotomy. Two jejunal segments were identified as sham-operated or instrumented segments. After baseline values were obtained, intraluminal distention was created in the experimental segment to induce an ntraluminal pressure of 18 cm H2O. After 120 minutes of distention, the intestine was decompressed for 120 minutes. Mesenteric ...
Ryan MP, McAuliffe O, Ross RP, Hill C.Lacticin 3147 is a broad-spectrum, two-component, lanthionine-containing bacteriocin produced by Lactococcus lactis DPC3147 which has widespread food and biomedical applications as a natural antimicrobial. Other two-component lantibiotics described to date include cytolysin and staphylococcin C55. Interestingly, cytolysin, produced by Enterococcus faecalis, has an associated haemolytic activity. The objective of this study was to compare the biological activity of lacticin 3147 with cytolysin. The lacticin 3147-encoding determinants were heterologously expressed in Ent. faecalis FA2-2, a plasm...
Keller M, Krehon S, Stanek C, Rosengarten R.Specimens of hoof horn from 187 horses were examined for a possible relationship between clinically affected hooves and the occurrence of pathogenic fungi. Specimens were taken from the coronary band and from the stratum externum and medium of the coronary horn and transferred on to Sabouraud dextrose agar, with and without cycloheximide, and incubated at 28 degrees C. Dermatophytes and mould fungi were identified by their macroscopic and microscopic characteristics. The 732 isolates could be assigned to 26 species of moulds, two different species of the dermatophyte Microsporum and three diff...
Sutcliffe IC, Trigg J, Harrington D.Using preparative electrophoresis, a low molecular weight protein has been partially purified from a cell extract of the equine pathogen Streptococcus equi susp. equi. N-terminal sequence analysis and Western blotting revealed the protein to be HPr, a central component of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). Interestingly, the only form of the HPr protein detected in S. equi was one with the amino-terminal methionine removed, a modification that has previously been associated with surface localization of streptococcal HPr proteins.
Yasuda R, Kawano J, Onda H, Takagi M, Shimizu A, Anzai T.To determine patterns of methicillin-resistant staphylococci isolated from apparently healthy horses. Methods: 44 horses from 8 riding clubs in Japan. Methods: Methicill in-resistant staphylococci were isolated from the skin or nares, using a selective medium containing a beta-(symboric) lactam antibiotic, ceftizoxime. Clonality of isolates was determined by use of pulsed-field gel electrophoresis. Detection of mecA, mecl, and mecR1 genes was accomplished by use of polymerase chain reactions. Results: Of the 44 horses, 13 (29.5%) yielded 15 isolates of methicillin-resistant staphylococci. The ...
Hamilton A, Harrington D, Sutcliffe IC.Acid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resis...
Yuki N, Shimazaki T, Kushiro A, Watanabe K, Uchida K, Yuyama T, Morotomi M.Selective adhesion to only certain epithelia is particularly common among the bacterial members of the indigenous microflora of mammals. We have found that the stratified squamous epithelium of the nonsecreting area of horse stomach is colonized by gram-positive rods. The microscopic features of a dense layer of these bacteria on the epithelium were found to be similar to those reported in mice, rats, and swine. Adhering microorganisms were isolated and identified as Lactobacillus salivarius, L. crispatus, L. reuteri, and L. agilis by DNA-DNA hybridization and 16S rRNA gene sequencing techniqu...
Mills ML, Rush BR, St Jean G, Gaughan EM, Mosier D, Gibson E, Freeman L.To determine the serum and synovial fluid concentrations of ceftiofur sodium after intraarticular (IA) and intravenous (IV) administration and to evaluate the morphologic changes after intraarticular ceftiofur sodium administration. Methods: Strip plot design for the ceftiofur sodium serum and synovial fluid concentrations and a split plot design for the cytologic and histopathologic evaluation. Methods: Six healthy adult horses without lameness. Methods: Stage 1: Ceftiofur sodium (2.2 mg/kg) was administered IV. Stage 2: 150 mg (3 mL) of ceftiofur sodium (pHavg 6.57) was administered IA into ...
Lakritz J, Wilson WD, Marsh AE, Mihalyi JE.To determine effects of prior feeding on pharmacokinetics and estimated bioavailability of orally administered microencapsulated erythromycin base (MEB) in healthy foals. Methods: 6 healthy foals, 3 to 5 months old. Methods: Foals were given 2 doses of MEB (25 mg/kg of body weight, PO). One dose was administered after food was withheld overnight, and the other was administered after foals had consumed hay. The study used a crossover design with a 2-week period between doses. Blood was collected via a jugular vein prior to and at specific times after drug administration. Concentrations of eryth...
Sarma PN, Tang YJ, Prindiville TP, Osborne PD, Jang S, Silva J, Cohen SH.In order to determine genetic relatedness of Bacteroides fragilis isolates from different clinical sources, arbitrarily primed polymerase chain reaction (PCR) (AP-PCR) was used to compare 17 strains isolated from patients with inflammatory bowel disease (IBD) and 20 strains isolated from foals with diarrhea. Three reference ATCC strains were also analyzed. Eighteen unique types were identified with a 22-mer arbitrary primer (ERIC-2) among the 20 patient isolates. Types 1 (enterotoxigenic) and 9 (nonenterotoxigenic), were each found in the stools of two patients. All other isolates showed a dis...
Collinder E, Berge GN, Grønvold B, Lindholm A, Midtved T, Norin E.This study investigated the influence of zinc bacitracin on the intestinal flora of horses. The functionally active intestinal flora was examined in 6 horses during treatment with zinc bacitracin. Utilising gas chromatography, spectrophotometry, gel electrophoresis and paper chromatography, samples were analysed on biochemical markers reflecting the action of parts of the intestinal flora. The following 5 flora-related functions were studied in faecal samples and intestinal samples from different sections of the hindgut: conversion of cholesterol to coprostanol and of bilirubin to urobilinogen...
Yu H, Raymonda JW, McMahon TM, Campagnari AA.This article reviews the recent development of two solid-phase chemiluminescence-based techniques, fluorogenic-chemiluminescence (FCL) and electro-chemiluminescence (ECL) for detection of biological threat agents. Both techniques entail a labeled sandwich immunoassay. The objectives of this work are to develop advanced techniques for sensitive and effective detection of a target analyte, particularly in cases where the analysis includes complex samples containing multiple contaminating factors. Other important considerations in developing such detection techniques include the ease of use, the ...
Thornton J.To determine if the microclimate is detrimental to horses during international air transportation in an enclosed container. Methods: On each of two 12 h and two 24 h flights three horses were transported in an enclosed container designed to prevent exposure to insect vectors. Heart rates were monitored throughout and blood samples were collected periodically. Air in the container was sampled for bacteria and fungal spores and the temperature and relative humidity were recorded inside and outside the container periodically during the flight. On the two 12 h flights similar observations were mad...
Martens RJ, Takai S, Cohen ND, Chaffin MK, Liu H, Sakurai K, Sugimoto H, Lingsweiler SW.To determine whether isolation and virulence of Rhodococcus equi from soil and infected foals are associated with clinical disease. Methods: Cross-sectional and case-control study. Methods: R equi isolates from 50 foals with pneumonia and soil samples from 33 farms with and 33 farms without a history of R equi infection (affected and control, respectively). Methods: R equi was selectively isolated from soil samples. Soil and clinical isolates were evaluated for virulence-associated protein antigen plasmids (VapA-P) and resistance to the beta-lactam antibiotics penicillin G and cephalothin. Mic...
Al-Ghamdi GM, Kapur V, Ames TR, Timoney JF, Love DN, Mellencamp MA.To determine whether repetitive sequence-based polymerase chain reaction (rep-PCR) could be used to differentiate Streptococcus equi isolates, to examine S equi isolates from throughout the world, and to determine whether a horse had > 1 subtype of S equi during an outbreak of disease. Methods: An initial group of 32 S equi isolates, 63 S equi isolates from various geographic areas, and 17 S equi isolates obtained during outbreaks of disease. Methods: An aliquot of S equi genomic DNA was amplified, using enterobacterial repetitive intergenic consensus primers. Gel electrophoresis was perfor...
Chanter N, Talbot NC, Newton JR, Hewson D, Verheyen K.The M-protein genes of Streptococcus equi isolated from 17 outwardly healthy horses after 4 strangles outbreaks had ended, including a quarantined animal, were compared with those of S. equi isolates from 167 active cases of strangles across 4 countries. The healthy horses included 16 persistent S. equi carriers, at least one from each of the four outbreaks. These carriers, despite being outwardly healthy, had empyema of the guttural pouch(es), an enlargement of the equine Eustachian tube. A persistent carrier from two of these outbreaks, the quarantined animal and a healthy animal with normal...
Collinder E, Lindholm A, Midtvedt T, Norin E.The aim of this study was to investigate 6 microflora-associated characteristics (MACs) in faecal samples from horses and to compare the results with baselines previously established in other mammals. A MAC is defined as any anatomical structure, physiological, biochemical or immunological characteristic in a host, which has been acted on by microorganisms. When the active microbes are absent, as in germ-free animals and healthy newborn organisms, the corresponding characteristic is defined as germ-free animal characteristic (GAC). The MACs studied were degradation of mucin, conversion of chol...
Pusterla N, Leutenegger CM, Sigrist B, Chae JS, Lutz H, Madigan JE.A real-time quantitative PCR using the TaqMan fluorogenic detection system (TaqMan PCR) was established for identification of Ehrlichia risticii, the agent of Potomac horse fever (PHF). The TaqMan PCR identified an 85 base pair section of the 16S rRNA gene by use of a specific fluorogenic probe and two primers. This technique was specific for eight tested E. risticii strains. The TaqMan system identified 10 copies of a cloned section of the 16S rRNA gene of E. risticii. The sensitivity and specificity of the TaqMan PCR were similar to those of conventional nested PCR. The TaqMan PCR was evalua...
Rashmir-Raven AM, Black SS, Rickard LG, Akin M.Papillomatous digital dermatitis is a common disease in cattle. The pastern dermatitis observed in a horse shared many of the gross characteristics of papillomatous digital dermatitis in cattle. Lesions included a mixture of proliferative and erosive changes, with a verrucose appearance in some areas. Microscopic similarities included pseudoepitheliomatous and papillomatous epidermal hyperplasia with hyperkeratosis, spongiosis of the epidermis, and intraepidermal spirochetes. The horse was also concurrently infected with Pelodera strongyloides. Papillomatous digital dermatitis in cattle is ass...
Renshaw RW, Glaser AL, Van Campen H, Weiland F, Dubovi EJ.A virus that could not be identified as a previously known equine virus was isolated from the mononuclear cells of a horse. Electron microscopy revealed enveloped virions with nucleocapsid structures characteristic of viruses in the Paramyxoviridae family. The virus failed to hemabsorb chicken or guinea pig red blood cells and lacked neuraminidase activity. Two viral genes were isolated from a cDNA expression library. Multiple sequence alignments of one gene indicated an average identity of 45% as compared to Morbillivirus N protein sequences. A weaker relationship was found with Tupaia paramy...
Lindeberg H, Karjalainen H, Koskinen E, Katila T.A study was performed to test a new semen collection device (Equidame phantom) that fractionates the ejaculate by comparing the quality of semen obtained by the Equidame phantom with that obtained by a Missouri artificial vagina. Semen from 4 Finnhorse stallions was collected 4 times per stallion by both methods. Half of the ejaculate was frozen and the other half extended and loaded into 2 Equitainer transport containers (24- and 48-h samples). Motility parameters were determined by a Hamilton-Thorn motility analyzer after cooled storage for 24 and 48 h and again after freezing/thawing. Raw a...
Pusterla N, Madigan JE, Chae JS, DeRock E, Johnson E, Pusterla JB.We report successful helminthic transmission of Ehrlichia risticii, the causative agent of Potomac horse fever, using trematode stages collected from Juga yrekaensis snails. The ehrlichial agent was isolated from the blood of experimentally infected horses by culture in murine monocytic cells and identified as E. risticii ultrastructurally and by characterization of three different genes.
Abdulmawjood A, Lämmler CH.The 16S rRNA gene of 39 S. equi subsp. zooepidemicus strains and two S. equi subsp. equi strains was amplified by polymerase chain reaction and subsequently digested with the restriction enzyme Hinc II. A restriction profile with two fragments with sizes of 1250 bp and 200 bp could be observed for both S. equi subsp. equi strains and for 30 of the 39 S. equi subsp. zooepidemicus strains indicating a sequence variation within the V2 region of the 16S rRNA gene of the remaining nine S. equi subsp. zooepidemicus isolates. A segment of the 16S rRNA gene including the hypervariable V2 region of 11 ...
Anzai T, Walker JA, Blair MB, Chambers TM, Timoney JF.To determine whether streptococcal pneumonia is caused by strains of Streptococcus zooepidemicus similar to those obtained from the tonsils of healthy horses. Methods: 5 tonsils from healthy horses, 8 tracheal washes and 6 lung specimens from foals with pneumonia, and 5 nasopharyngeal swab specimens from donkeys with acute bronchopneumonia. Methods: Variable M-like protectively immunogenic SzP proteins of 5 isolates of S. zooepidemicus from each tonsil and clinical specimen were compared, using immunoblots. The SzP gene of 13 isolates representative of various SzP immunoblot phenotypes from 1 ...
Gianini M, Sutter O, Burger D, Bracher V.Gastrointestinal function was assessed in normal foals before, during and after the onset of 'foal heat diarrhoea' by haematological, biochemical, microbiological and parasitological methods, and by a combined lactose tolerance-breath hydrogen excretion test. Warmblood mares (n=11) and their foals were used. The foals were assessed according to a standard protocol after birth and at regular intervals thereafter. All except one of the foals suffered from diarrhoea that started between day 8 and day 12 after birth, which lasted for 1-4 days. Rotavirus was detected in the faeces of five foals, bu...
Kawamura Y, Fujimoto Y, Kutsuna R, Tomida J, Yamamoto KI, Miyoshi-Akiyama T, Okuno M, Ogura Y, Matsuoka M, Kawaguchi T, Tsutsuki H, Sawa T.A Gram-stain-negative, spiral bacterium (PAGU 1991T) was isolated from the blood of a patient with diffuse large B-cell lymphoma. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate was very closely related to Helicobacter equorum LMG 23362T (99.1 % similarity), originally isolated from a faecal sample from a healthy horse. PAGU 1991T was also very closely related to PAGU 1750 in our strain library (=CCUG 41437) with 99.7 % similarity. Additional phylogenetic analyses based on the 23S rRNA gene sequence and GyrA amino acid sequence further supported the close rel...
Stros K, Krivanec K, Komárek J, Malinský B.There is a description of equine dermatophytosis enzootic, caused by the microscopic fungus Trichophyton equinum. The disease affected 32 horses, mostly young, all in the same herd (74.4%). The diseased horses were successfully treated with the preparation Fenoform forte, applied superficially at the concentration of 0.5% of the active substance. The authors made an attempt to determine the criteria for clinical differentiation of fully developed trichophytosis and microsporosis of horses. Trichophytosis (T. equinum) is characterized as typical numerous small and round patches, covered by smal...
Wilson WD, Baggot JD, Adamson PJ, Hirsh DC, Hietala SK.Sodium cefadroxil was administered as a single intravenous dose (25 mg/kg) to six healthy adult mares. Plasma samples were collected over a 24-h period and cefadroxil concentrations were measured by microbiological assay. The pharmacokinetic behavior of the drug was appropriately described in terms of a one-compartment open model. Values for the major pharmacokinetic terms were: extrapolated initial plasma concentration = 59.2 +/- 15.0 micrograms/ml; half-life = 46 +/- 20 min; apparent volume of distribution = 462 +/- 191 ml/kg; and body clearance = 7.0 +/- 0.6 ml/min.kg. In a subsequent study...
Heilkenbrinker T, Schubert TS, Oetjen J, Pózvári M, Frerking H.In this thesis the influence of pneumo-vagina on the microbiological colonization of the genital tract and their manifestation in cytological smears was examined. For mares with poor vulval conformation a comparison of the bacterial growth before and after plastic surgery of the vulva and vestibulum was carried out, as well as the registration of conception rates after operation and insemination. The biggest reduction of the bacterial content in the reproductive tract was found between vestibulum and cranial section of the vagina. The increased number of contaminant bacteria in the cranial sec...
Gharaibeh MH, Abutarbush SM, Mustafa FG, Lafi SQ, Halaiqa MS.Antimicrobial resistance is a growing global problem that will need a multinational collaborative effort to overcome this serious challenge. The aim of the study is to investigate the potential risk factors associated with the prevalence and distribution of antimicrobial-resistance genes (ARGs) of Escherichia coli isolates obtained from equine fecal samples. One hundred and eighteen horses from different geographical locations and management systems were enrolled in the study and a questionnaire containing information about each individual horse was designed and filled. The enrolled horses bel...
Bonhomme-Florentin A.Cecum microfauna association with different plant tissues was examined by scanning and transmission electron microscopy. The ciliates were attached to the damaged areas of the leaves and their highest concentrations were found on the epidermis and mesophyll tissues. The degradation of plant tissue was due to protozoal ingestion of the plant fragments. The morphology of ingested envacuolized chloroplasts changed rapidly, showing different stages of digestion inside the ciliate endoplasm. Intact chloroplasts were rarely observed but the grana of fragmented thylakoid membranes was often seen. The...
Costa D, Leiva M, Naranjo C, Ríos J, Peña MT.To evaluate microbiological, histological, and ultrastructural characteristics of short-term cryopreserved (STC) equine corneoscleral tissue (7 years). Methods: Thirty-four healthy equine globes. Methods: After a decontamination protocol, globes were enucleated and stored at -20°C in broad-spectrum antibiotics. Corneoscleral tissue was evaluated at different storage periods: 1 month-1 year (20 eyes) and 7-9 years (12 eyes). Two eyes were used as controls. Microbiologic study included direct (blood, McConkey, and Sabouraud agars) and enrichment (brain-heart infusion broth) cultures. Cryopr...
Crabill MR, Cohen ND, Martin LJ, Simpson RB, Burney N.Equine synovial fluid aliquots were inoculated with Salmonella enteritidis, Escherichia coli, Actinobacillus equuli, Staphylococcus aureus, and Streptococcus zooepidemicus to obtain approximate concentrations of 1000, 100, 10, and 1 colony forming U/mL. Synovial fluid aliquots were also inoculated with an unquantitated inoculum of Bacteroides fragilis and Clostridium perfringens. Inoculated synovial fluid was incubated in trypticase-soy broth or Columbia broth for approximately 12 hours. Then aliquots were removed for DNA extraction and polymerase chain reaction (PCR) analysis for detection of...
Rawlinson RJ, Jones RT.The history and clinical findings of 1 horses with guttural pouch mycosis referred to us are described. The salient features of the history and clinical signs common to both cases were profuse spontaneous nasal haemorrhage, partial pharyngeal paralysis; subsequently bilateral nasal discharge containing food material, inability to drink and parotid pain became evident. One case made a gradual recovery with conservative medical treatment while the second case was destroyed and submitted for post-mortem, histopathological and microbiological examination. This examination failed to establish the i...
Boldbaatar B, Bazartseren T, Koba R, Murakami H, Oguma K, Murakami K, Sentsui H.In the current study, primers described previously and modified versions of these primers were evaluated for amplification of full-length gag genes from different equine infectious anemia virus (EIAV) strains from several countries, including the USA, Germany and Japan. Each strain was inoculated into a primary horse leukocyte culture, and the full-length gag gene was amplified by reverse transcription polymerase chain reaction. Each amplified gag gene was cloned into a plasmid vector for sequencing, and the detectable copy numbers of target DNA were determined. Use of a mixture of two forward...
Cedrola F, Bordim S, D'Agosto M, Dias RJP.The aims of this study were to identify and quantify the gastrointestinal ciliates from Brazilian domestic horses, to compare the data obtained with previous studies and to review data on ciliate communities associated with horses around the world. We used eight domestic horses, kept under extensive management. Fecal samples were obtained immediately after defecation of animals and fixed in 18.5% formaldehyde. We identify 24 species of endosymbiotic ciliates, distributed in two subclasses, two orders, five families and 13 genera. The ciliate composition was similar among the animals analyzed. ...
Mohan K, Muvavarirwa P, Pawandiwa A.Among the Actinobacillus spp. only A. lignieresii represents a homogenous and well studied taxon. However, haemolytic and non-haemolytic strains of A. equuli and A. suis are also isolated from a wide range of diseases in a variety of hosts. These isolates often pose problems in definitive identification. Consequently, several studies have been published, emphasizing the need for detailed studies to reclassify various members of this genus and also to assess their disease significance. We isolated 48 strains of Actinobacillus from clinical cases in horses, cattle, sheep, cat, pigs and ostrich. ...
Blackall PJ, Christensen JP, Bisgaard M.The objective of this work was to examine the diversity within Australian isolates of Actinobacillus equuli and related organisms by the genotypic method of ribotyping. Methods: Ribotyping, performed using the enzyme HaeIII, was used to examine the diversity in 12 field isolates of A equuli (five being capable of fermenting L-arabinose), one field isolate of Pasteurella caballi and two unclassifiable field isolates. Isolates were obtained from Australian horses, except for three isolates of A equuli (one L-arabinose positive and two L-arabinose negative) which were obtained from horses and a p...
Bass LG, Peña-Álvarez P, Hidalgo-Dittel JD, Robles-Herrera FD, Cappella-Flores PM, Zúñiga-Cortés DS, Olivares RWI.Sarcina spp. is a Gram-positive, coccoid microorganism that forms tetrads or octets, and is observed with a characteristic "bundle" arrangement. The most recognized species are Sarcina ventriculi and Sarcina maxima. It has been described as part of the normal microbiota in horses and cats, but it has also been linked to abomasal bloat in goats, lambs, and calves, although its causality has not been proven yet. This work presents the case of a 3-months-old female horse that died of generalized tympanism. Macroscopic findings showed mild cyanosis and abundant gas in the lumen of the stomach, and...
Rey F, Hallebeek JM, Beynen AC.The question addressed was whether apparent crude fibre digestibility in ponies would change after lowering protein intake from adequate to borderline deficient. Four adult ponies were fed a low- and high-protein diet according to a cross-over design. The diets consisted of grass hay and concentrates and provided either 1.5 or 3.6 g digestible crude protein/kg(0.75) per day. The two whole rations provided 2.4 g crude fibre/kg body weight per day. Apparent crude fibre digestibility was not affected by protein intake (low-protein diet: 42.9 +/- 4.03%; high-protein diet: 38.1 +/- 1.14%, means +/-...
Linn-Peirano SC, Hepworth-Warren K, Kinsella H, Diaz-Campos D, Brenseke BM, Cianciolo RE, Schroeder E, Schreeg ME.Equine ingesta-associated choledocholithiasis is a rare cause of morbidity and mortality. We describe here the clinical, gross, histologic, and microbiologic features of this condition in 2 horses and compare the features to 2 previous cases. Case 1 was a 4-y-old Thoroughbred mare with colic. Case 2 was an 18-y-old American Paint Horse mare with colic, chronic weight loss, and inappropriate mentation. Both had elevated biochemical markers of hepatocellular injury and cholestasis and were euthanized given a poor prognosis. Case 1 had a well-formed 5-cm choledocholith surrounding a piece of hay,...
Labeda DP, Price NP, Kroppenstedt RM, Donahue JM, Williams NM, Sells SF.Two actinomycete strains, NRRL B-24165(T) and NRRL B-24166(T), isolated from lesions on equine placentas in Kentucky, USA, were analysed using a polyphasic taxonomic approach. On the basis of phylogenetic analysis of 16S rRNA gene sequences, morphological observations and the presence of ll-diaminopimelic acid as the diagnostic diamino acid in whole-cell hydrolysates, the new isolates clearly belonged to the genus Streptomyces. Analyses of the phylogenetic positions of strains NRRL B-24165(T) and NRRL B-24166(T) based on 16S rRNA gene sequences of all recognized species of the genus Streptomyc...
Hopper N, Singer E, Henson F.The exact aetiology and pathogenesis of microdamage-induced long bone fractures remain unknown. These fractures are likely to be the result of inadequate bone remodelling in response to damage. This study aims to identify an association of osteocyte apoptosis, the presence of osteocytic osteolysis, and any alterations in sclerostin expression with a fracture of the third metacarpal (Mc-III) bone of Thoroughbred racehorses. Methods: A total of 30 Mc-III bones were obtained; ten bones were fractured during racing, ten were from the contralateral limb, and ten were from control horses. Each Mc-II...
Intemann S, Reckels B, Schubert DC, Wolf P, Kamphues J, Visscher C.Evidence has already been provided that feed-borne mold spores and endotoxins can trigger chronic, non-infectious respiratory disease if inhaled. Furthermore, deficiencies in feed microbiology are suspected to trigger gastrointestinal and liver disorders in horses, but the connection needs further clarification. Most of the previous studies regarding horse feed hygiene focused on forage, whereas research regarding hygienic quality of concentrates is scarce. In the present study, results of reports on hygienic quality of compound feed and cereals for horses were evaluated secondarily. Results i...
Balke E, Weiss R, Seipp A.A total of 110 strains of beta-hemolytic streptococci, belonging to serogroup C (Lancefield), isolated from horses (71 S. zooepidemicus, 27 S. equisimilis and 12 S. equi) as well as 5 reference strains were tested for their ability to produce hyaluronidase. The determinations were carried out in a culture test on agarose gel and in a liquid test system (turbidity test according to DiFerrante). The results of both methods used showed that the three Streptococcus species could be differentiated by the relative quantitative determination of hyaluronidase activity. S. equisimilis strains produce 5...
Hasegawa M, Amano A, Muraoka H, Kobayashi I, Kimoto M, Kato M, Fujioka T, Nasu M.We conducted a study for the growth of and selectivity for the desired microorganisms using a newly developed selective culture medium for Helicobacter pylori, Columbia horse blood agar HP (CHBHP), at three different Japanese clinical laboratories, Hokkaido, Kanto and Kyusyu. When standard strains and clinical isolates of H. pylori were examined, the recovery of the organism on the CHBHP media was comparable to that of conventional selective and nonselective media. However, colonies were obviously larger on the CHBHP media. These media yielded the highest H. pylori positive rate for clinical s...
Fodor L, Szenci O, Peters M, Varga J, Szemerédi G, Wyszoczky F.A total of seven Bacteroides ureolyticus strains were isolated from the cervix and the clitoral fossa of mares with vaginal discharge. No other bacteria capable of causing metritis or vaginitis were isolated from the samples. The isolated strains resembled Taylorella equigenitalis. Both species are catalase, oxidase and alkaline phosphatase positive, but, in addition to these characteristics, B. ureolyticus strains produced urease and they could not tolerate 10% O2. They also failed to be agglutinated in a hyperimmune serum raised against T. equigenitalis; however, B. ureolyticus and T. equige...
Lanka S, Borst LB, Patterson SK, Maddox CW.The objective of the present investigation was to differentiate between strains of Streptococcus equi subspecies equi implicated in abscess formation in vaccinated horses. Streptococcus equi isolates recovered from clinical specimens associated with equine strangles cases submitted to the University of Illinois Veterinary Diagnostic Laboratory were compared with S. equi isolates representing at least 12 lots of a commercial modified live vaccine (MLV) to determine whether the isolates obtained from the abscesses were vaccine or wild type. Genotyping techniques evaluated included enterobacteria...
Hill AC, Polak-Vogelzang AA, Angulo AF.Acholeplasma strains were isolated from the nasopharynx of a horse (strain PN525T [T = type strain]) and the feces of a rabbit (strain B1). One clone of strain PN525T and one clone of strain B1 were examined in detail. These clones were indistinguishable from each other and were serologically distinct from the previously described Acholeplasma and Mycoplasma spp. The strains had the following properties: guanine-plus-cytosine content of 31 mol%; sterol was not required for growth, which occurred under both aerobic and anaerobic conditions; glucose was metabolized; and arginine was hydrolyzed. ...
Lauková A, Micenková L, Kubašová I, Bino E, Kandričáková A, Plachá I, Štrkolcová G, Gálik B, Kováčik A, Halo M, Simonová MP.The beneficial influence of bacteriocin-producing, probiotic, mostly non-autochthonous bacteria has already been reported in various animals. However, their use in horses provides limited information, and results with autochthonous bacteria have not been reported. Therefore, the main objective of this model study was to test the effect of autochthonous, bacteriocin-producing faecal strain Enterococcus faecium EF 412 application in horses. One gram of freeze-dried EF 412 strain (10 CFU/mL for 21 days) was applied to horses in a small feed ball. Clinically healthy horses (12), Slovak warm-blood ...
Morris BA, Sadana A.A fractal analysis is presented for the detection of pathogens such as Franscisela tularensis, Yersinia pestis (the bacterium that causes plague), Bacillus anthracis, Venezuelan equine encephalitis (VEE) virus, Vavcinia virus, and Escherichia coli using a cellular analysis and notification of antigens risks and yields (CANARY) biosensor [T.H. Rider, M.S. Petrovic, F.E. Nargi, J.D Harper, E.D. Schwoebel, R.H. Mathews, D.J. Blanchard, L.T Bortolin, A.M. Young, J. Chen, M.A. Hollis, A cell-based sensor for rapid identification of pathogens, Science 301 (2003, 11 July) 213-215, T.H. Rider, M.S. Pe...
HARDY FM, ARBITER D.Hardy, Frank M. (Fort Detrick, Frederick, Md.), and David Arbiter. Lipid inclusions in L cells associated with Venezuelan equine encephalomyelitis virus infection. J. Bacteriol. 89:1101-1103. 1965.-Venezuelan equine encephalomyelitis (VEE) virus has been shown to induce changes of lipid components within the L cell. Lipid inclusions in the form of dark granular bodies were observed in the L cell after aqueous osmium tetroxide fixation and Sudan black staining. Microscopic examination of cells as early as 8 hr after infection with VEE virus showed an increase in the concentration of these inclu...
Das SC, Kapoor KN.The present study was undertaken to evaluate the effect of growth medium on expression of hydrophobicity of Staphylococcus epidermidis. A total of 24 hydrophobic isolates of S. epidermidis, determined by n-hexadecane adherence assay (HAA) earlier were included. Five different growth media: horse blood agar (HBA), brain heart infusion agar (BHIA), brain heart infusion broth (BHIB), tryptic soy broth (TSB) and proteose peptone broth (PPB) were used. All 24 isolates exhibited the reproducible hydrophobicity when grown on HBA; however, 20 (83.33%), 19 (79.16%), 15 (62.50%) and 13 (54.16%) isolates...
Takai S, Sudo M, Sakai M, Suzuki K, Sasaki Y, Kakuda T, Suzuki Y.Rhodococcus equi was isolated from the gastrointestinal contents of earthworms (family Megascolecidae) and their surrounding soil collected from pastures of two horse-breeding farms in Aomori Prefecture, outdoor pig pens, forest in Towada campus, orange groves and forest where wild boars (Sus scrofa) are established in Tanabe, Wakayama Prefecture. The number of R. equi in the lower gastrointestinal contents of 23 earthworms collected from our campus was significantly larger than that of the upper gastrointestinal content. The mean numbers of R. equi from the gastrointestinal contents of earthw...
García EDA, Khusro A, Pacheco EBF, Adegbeye MJ, Barbabosa-Pliego A, Lagunas BC, Salas JMC, Mateos RG, Aarti C, Elghandour MMMY.The present context was designed to investigate the efficacy of devil fish (DF; Plecostomus sp.) silage and Staphylococcus saprophyticus on fermentation characteristics as well as greenhouse gases production mitigation attributes in horses. Four levels of ensiled DF at 0 (control DF0), 6 (DF6), 12 (DF12), and 18 (DF18) % were added into the diet. Moreover, three doses of S. saprophyticus (0, 1, and 3 mL/g dry matter [DM]) were used for in vitro fecal fermentation. The use of ensiled DF resulted in increased (P < .0001) pH during fermentation. The asymptotic gas production was the highest (P...