Infectious diseases in horses encompass a range of illnesses caused by bacteria, viruses, fungi, or parasites. These diseases can affect various systems within the equine body, leading to symptoms that range from mild discomfort to severe systemic illness. Common infectious diseases in horses include equine influenza, strangles, equine herpesvirus, and West Nile virus. These diseases can be transmitted through direct contact with infected animals, contaminated surfaces, or vectors such as insects. Understanding the mechanisms of transmission, pathogenesis, and immune response is essential for effective prevention and control. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, diagnosis, treatment, and management of infectious diseases in horses.
Ousey JC, Palmer L, Cash RS, Grimes KJ, Fletcher AP, Barrelet A, Foote AK, Manning FM, Ricketts SW.Standard bacteriological methods for identifying Taylorella equigenitalis in cervical smears are time consuming. Therefore, a more rapid real-time PCR assay was evaluated for its suitability in screening swabs. Objective: To compare the results of a commercially available real-time PCR assay with routine microbiological culture for the identification of T. equigenitalis, the causative organism of contagious equine metritis, in equine genital swab samples, under 'field trial' conditions. Methods: Routine prebreeding genital swabs (n=2072) collected from Thoroughbred mares and stallions during 2...
Hajialilo E, Ziaali N, Harandi MF, Saraei M, Hajialilo M.In the present study, the prevalence of antibodies to Toxoplasma gondii in sport horses of Qazvin was examined using modified agglutination test (MAT). On 52 horse sera totally examined for anti-Toxoplasma antibodies, 37 horses (71.2%) were seropositive by MAT. Results of the present study showed a high rate of Toxoplasma infection in horses in Qazvin area. More comprehensive study on equine toxoplasmosis is recommended.
Rogers CW, Cogger N.To examine the on-farm biosecurity practices of a group of commercial Thoroughbred stud farms in the North Island of New Zealand, in the absence of an exotic disease outbreak. Methods: A cross-sectional survey of biosecurity practices was conducted during the 2006/2007 Thoroughbred breeding season, and consisted of data from commercial Thoroughbred farms in the North Island of New Zealand standing a stallion. Data were collected on-farm by a single interviewer, using 17 open, closed and multiple-choice questions examining general farm/operation size and features, general animal health and bios...
Abbott Y, Leggett B, Rossney AS, Leonard FC, Markey BK.A retrospective analysis and prospective surveillance study were conducted to determine isolation rates of meticillin-resistant Staphylococcus aureus (MRSA) in dogs, cats and horses in Ireland. Clinical samples that had been submitted to University College Dublin (UCD) for routine microbiological examination over a four-year period (2003 to 2006) were analysed in the retrospective analysis, which included clinical samples from 3866 animals. In the prospective surveillance study, samples from healthy animals presenting for elective surgery as well as from animals with a clinical presentation su...
Pronost S, Léon A, Legrand L, Fortier C, Miszczak F, Freymuth F, Fortier G.Equine herpesvirus 1 (EHV-1) is a common pathogen of the horse which may induce mild respiratory distress, abortion, neonatal death and neurological disease. A single nucleotide polymorphism in the EHV-1 DNA polymerase (ORF30 A(2254) to G(2254)) has been associated with clinical signs of Equine herpes myeloencephalopathy (EHM). The aim of this work was to analyze the ORF30 genomic region among a panel of EHV-1 DNA extract in order to estimate the prevalence of the EHV-1 neuropathogenic genotype in France. Samples coming from cases associated with EHM, horses with respiratory symptoms and abort...
Groppelli E, Tuthill TJ, Rowlands DJ.Equine rhinitis A virus (ERAV) is genetically closely related to foot-and-mouth disease virus (FMDV), and both are now classified within the genus Aphthovirus of the family Picornaviridae. For disease security reasons, FMDV can be handled only in high-containment facilities, but these constraints do not apply to ERAV, making it an attractive alternative for the study of aphthovirus biology. Here, we show, using immunofluorescence, pharmacological agents, and dominant negative inhibitors, that ERAV entry occurs (as for FMDV) via clathrin-mediated endocytosis and acidification of early endosomes...
Araujo JM, Araújo JV, Braga FR, Carvalho RO.Three isolates of predator fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34), and Arthrobotrys robusta (I-31) were assessed in in vitro test regarding the capacity of prey infective larvae (L(3)) Strongyloides westeri. Compared to control, without fungus, there was a significant decrease (P 0.01) in vitro test. Linear regression coefficients of treated and control groups were -0.21 for control, -0.32 for D. flagrans, -0.34 for M. thaumasium, and -0.22 for A. robusta. In the following, isolates AC001 and NF34 were assessed in vivo regarding the capacity of supporting the pa...
Medina-Torres CE, Weese JS, Staempfli HR.Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Objective: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Methods: Samples were obtained from 72 horses p...
Panchaud Y, Gerber V, Rossano A, Perreten V.Bacterial infections present a major challenge in equine medicine. Therapy should be based on bacteriological diagnosis to successfully minimize the increasing number of infections caused by multidrug-resistant bacteria. The present study is a retrospective analysis of bacteriological results from purulent infections in horses admitted at the University Equine Clinic of Bern from 2004 to 2008. From 378 samples analyzed, 557 isolates were identified, of which Staphylococcus aureus, Streptococcus equi subsp. zooepidemicus and coliforms were the most common. Special attention was paid to infectio...
Brooks BW, Lutze-Wallace CL, Maclean LL, Vinogradov E, Perry MB.Lipopolysaccharides (LPSs) from Taylorella equigenitalis, the causative agent of contagious equine metritis, and T. asinigenitalis were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Lipopolysaccharide profiles of 11 T. equigenitalis strains were similar, but different from the profiles of 3 T. asinigenitalis strains, and the profiles of 2 T. asinigenitalis strains were similar to each other. The serological specificities of the LPSs from these 14 strains were examined by immunoblotting and enzyme-linked immunosorbent assay with monoclonal antibodies (MAbs) ...
Hagos A, Goddeeris BM, Yilkal K, Alemu T, Fikru R, Yacob HT, Feseha G, Claes F.Trypanocidal sensitivity studies were conducted to assess the efficacy of Diminazene diaceturate (Diminasan) and Bis (aminoethylthio) 4-melaminophenylarsine dihydrochloride (Cymelarsan) against Trypanosoma equiperdum (isolated from two mares with chronic cases of dourine) 713/943 and 834/940 Dodola strains in experimentally infected mice and horses. Diminasan at doses from 3.5 mg/kg to 28 mg/kg and Cymelarsan at doses of 0.25 mg/kg and 0.5 mg/kg body weight failed to cure any of the mice, indicating a clear dose dependent relationship in the mean time of relapse observed in mice. Indeed, mice ...
Kirkland PD, Finlaison DS, Crispe E, Hurt AC.During the 2007 equine influenza outbreak in Australia, respiratory disease in dogs in close contact with infected horses was noted; influenza (H3N8) virus infection was confirmed. Nucleotide sequence of the virus from dogs was identical to that from horses. No evidence of dog-to-dog transmission or virus persistence in dogs was found.
Alvarez I, Gutierrez G, Barrandeguy M, Trono K.The purpose of this study was to develop and evaluate a simple immunochromatographic lateral flow (ICLF) test for specific detection of Equine infectious anemia virus (EIAV) antibodies in equine sera. Viral recombinant p26 capsid protein (rp26) was used as the capture protein in the test line and as the detector reagent conjugated to colloidal gold. The performance of rp26-ICLF was evaluated, and the results obtained were compared with a commercially available agar gel immunodiffusion (AGID) test used as a standard of comparison according to international guidelines. The values obtained for co...
Ackerson LK, Viswanath K.Previous research has found that members of the public have a skewed sense of health risk. The purpose of this research was to investigate how mass media use influences perceptions of threat from cancer and eastern equine encephalitis (EEE). Investigators performed a media content analysis of 253 health-related articles from 11 Massachusetts newspapers, then used logistic regression to analyze responses to a health communication survey of 613 Massachusetts adults. A greater proportion of cancer articles compared to those about EEE mentioned progress in combating the disease (61.0% vs. 16.2%, P...
Turowska A, Pajak B, Godlewski MM, Dzieciatkowski T, Chmielewska A, Tucholska A, Banbura M.Viruses can reorganize the cytoskeleton and restructure the host cell transport machinery. During infection viruses use different cellular cues and signals to enlist the cytoskeleton for their mission. However, each virus specifically affects the cytoskeleton structure. Thus, the aim of our study was to investigate the cytoskeletal changes in homologous equine dermal (ED) and heterologous Vero cell lines infected with either equine herpesvirus 1 (EHV-1) strain Rac-H or Jan-E. We found that Rac-H strain disrupted actin fibers and reduced F-actin level in ED cells, whereas the virus did not infl...
Paillot R, Prowse L, Donald C, Medcalf E, Montesso F, Bryant N, Watson J, Jeggo M, Elton D, Newton R, Trail P, Barnes H.An outbreak of H3N8 Equine Influenza virus (EIV) that occurred in vaccinated horses in Japan was caused by a genetically divergent EIV isolate of the Florida clade 1 sub-lineage. This virus subsequently entered Australia where it infected thousands of immunologically naïve horses. The objective of this study was to evaluate the ability of a non-updated whole inactivated equine influenza (EI) vaccine to protect if used in the face of an outbreak induced by a virus similar to the ones circulating in Japan and Australia in 2007. Seven naïve Welsh mountain ponies were immunised twice with the co...
Quan M, Lourens CW, MacLachlan NJ, Gardner IA, Guthrie AJ.Nucleotide sequences of 52 South African isolates of African horse sickness virus (AHSV) collected during 2004-2005 and including viruses of all nine AHSV serotypes, were used to design and develop a duplex real-time reverse transcription quantitative PCR (RT-PCR) assay targeting the VP7 (S8) and NS2 (S9) genes of AHSV. The assay was optimized for detection of AHSV in fresh and frozen blood of naturally infected horses. Assay performance was enhanced using random hexamers rather than gene-specific primers for RT, and with denaturation of double-stranded RNA in the presence of random hexamers. ...
Harris SP, Fujiwara N, Mealey RH, Alperin DC, Naka T, Goda R, Hines SA.Immune adult horses have CD8(+) cytotoxic T lymphocytes (CTLs) that recognize and lyse Rhodococcus equi-infected cells in an equine lymphocyte alloantigen (ELA)-A [classical major histocompatibility complex (MHC) class I]-unrestricted fashion. As protein antigens are MHC class I-restricted, the lack of restriction suggests that the bacterial antigens being recognized by the host are not proteins. The goals of this study were to test the hypothesis that these CTLs recognize unique R. equi cell-wall lipids related to mycobacterial lipids. Initial experiments showed that treatment of soluble R. e...
Kitai Y, Kondo T, Konishi E.A complement-dependent cytotoxicity (CDC) assay was established to measure antibodies to the West Nile virus (WNV) nonstructural protein 1 (NS1) in horses. Sera collected from a WNV-infected horse mediated lysis of WNV NS1-expressing cells in a dose-dependent manner at higher percentages than sera from a Japanese encephalitis virus (JEV)-infected horse. The percentages of specific lysis for sera diluted 1:10 to 1:80 were <19.8% (assay cutoff) for almost all of the 100 JEV-infected or uninfected horses tested, in contrast to 55 to 76% in WNV-infected horses. Experimental infection revealed t...
Garner MG, Cowled B, East IJ, Moloney BJ, Kung NY.In August 2007, Australia which had previously been free of equine influenza, experienced a large outbreak that lasted approximately 4 months before it was eradicated. The outbreak required a significant national response by government and the horse industries. The main components of the response were movement controls, biosecurity measures, risk-based zoning and, subsequently, vaccination to contain the outbreak. Although not initially used, vaccination became a key element in the eradication program, with approximately 140000 horses vaccinated. Vaccination is recognised as a valuable tool fo...
Malik P, Khurana SK, Dwivedi SK.Glanders, a notifiable highly contagious disease primarily of equids, is a disease of high zoonotic importance. Caused by gram-negative bacillus, Burkholderia mallei, the disease was restricted to certain pockets of India with sporadic cases. Recently, a major outbreak of glanders occurred in India starting from Maharashtra. Following clinical signs and symptoms and laboratory investigations on serum, nasal swab and pus swab samples, it was confirmed as glanders among equines in Pune and Panchgani areas of Maharashtra. One pus sample and three nasal swabs yielded B. mallei isolates while 23 se...
Nishiura H, Satou K.An outbreak of equine influenza (H3N8) occurred among fully vaccinated racehorses in Japan from August to September, 2007. To assess the potential effectiveness of public health interventions other than vaccination (i.e. movement restriction, isolation and quarantine), which started immediately on the date of detection of the first febrile case, a simple epidemiological model was developed and applied to the observed data. The epidemic curves in five racehorse facilities revealed consistent temporal patterns: (i) a sharp increase in symptom onset of cases during the first 3 days, which is thou...
Johnson AL, McAdams SC, Whitlock RH.The objective of the current retrospective study was to describe naturally occurring type A botulism in horses in the United States. In the past 10 years, the Botulism Laboratory at the University of Pennsylvania's School of Veterinary Medicine has identified 3 isolated cases and 8 outbreaks of type A botulism in horses via samples positive for Clostridium botulinum type A toxin or spores using the mouse bioassay test. Additional information was obtained by review of submission forms and by telephone or email interviews. Almost all type A cases and outbreaks occurred in the western United Stat...
Meehan M, Burke FM, Macken S, Owen P.Streptococcus equi possesses a haem-uptake system homologous to that of Streptococcus pyogenes and Streptococcus zooepidemicus. The system consists of two ligand-binding proteins (Shr and Shp) and proteins (HtsA-C) with homology to an ABC transporter. The haem-uptake system of S. equi differs from that of S. pyogenes and S. zooepidemicus in that Shr is truncated by two-thirds. This study focused on the SeShr, SeShp and SeHtsA proteins of S. equi. Analysis of shr, shp and shphtsA knockout mutants showed that all three proteins were expressed in vitro and that expression was upregulated under co...
Pusterla N, Wattanaphansak S, Mapes S, Collier J, Hill J, Difrancesco M, Gebhart C.Equine proliferative enteropathy (EPE) is an emerging disease of weanling foals. Objective: Describe clinical, hematologic, biochemical, serologic, molecular, and ultrasonographic findings in foals experimentally infected with Lawsonia intracellularis. Methods: Eight foals. Methods: Recently weaned foals were assigned to either the challenge (n = 3), the sentinel (n = 3), or the control (n = 2) group. Foals were experimentally challenged via intragastric inoculation of 3 x 10(10)L. intracellularis organisms grown in culture. Each experimentally infected foal was housed with a sentinel foal in ...
Go YY, Zhang J, Timoney PJ, Cook RF, Horohov DW, Balasuriya UB.Extensive cell culture passage of the virulent Bucyrus (VB) strain of equine arteritis virus (EAV) to produce the modified live virus (MLV) vaccine strain has altered its tropism for equine CD3(+) T lymphocytes and CD14(+) monocytes. The VB strain primarily infects CD14(+) monocytes and a small subpopulation of CD3(+) T lymphocytes (predominantly CD4(+) T lymphocytes), as determined by dual-color flow cytometry. In contrast, the MLV vaccine strain has a significantly reduced ability to infect CD14(+) monocytes and has lost its capability to infect CD3(+) T lymphocytes. Using a panel of five re...
Fritz D.Positive PCR results for piroplasms were obtained on EDTA blood samples from 166 dogs and 111 horses between March 2006 and March 2008. The organisms were initially identified using common primers, followed by restriction enzyme profiles to determine the species and types of Babesia/Theileria. In 27 dogs and eight horses with positive results, the size of the specimen was insufficient to separate species/types. We identified Babesia canis canis in 105 of the 166 dogs (63%) and Theileria equi in 89 of the 111 horses (80%). Babesia caballi was also present, but rare, in only two Babesia/Theileri...
Tallmadge RL, Žygelytė E, Van de Walle GR, Kristie TM, Felippe MJB.Equine herpesvirus type 1 (EHV-1) is a ubiquitous and highly contagious pathogen that causes a range of disease severities with outbreaks of notable economic impact. Given the limitations in immune protection of current vaccines and the limited effectiveness of antiviral drugs on EHV-1 infections , improved treatment measures are needed to control disease. The use of drugs that alter the epigenetic state of herpes simplex virus genome has been shown to limit viral primary infection and reactivation both and . Therefore, we tested the hypothesis that maintaining a repressive epigenetic state o...
Gard GP, Marshall ID, Walker KH, Acland HM, Saren WG.An outbreak of Murray Valley encephalitis (MVE) occurred in New South Wales during the first five months of 1974. Specimens from 52 horses with nervous disease collected January to May 1974 were examined histopathological or virologically. Although MVE virus was not isolated, 13 horses had serological evidence of recent infection with MVE virus. Another 4 horses had evidence of recent infection with Ross River virus. Two animals had histological evidence of viral infection of the central nervous system. Attempts to experimentally infect 2 horses with a low dose of MVE virus were not successful...
Ladds PW, Thomas AD, Pott B.A case of acute meningoencephalomyelitis caused by infection with Pseudomonas pseudomallei is described. Clinically there was inability to stand, opisthotonus, facial paralysis and nystagmus, rapidly progressing to violent struggling. Gross examination revealed malacia and haemorrhage in the medulla oblongata and adjacent spinal cord. Microscopically there were disseminated focal neutrophilic accumulations in affected areas, perivascular cuffing with mononuclear cells and lymphocytes and marked oedema. Intracellular bacteria were identified in sections stained by the Giemsa method.
Jindra C, Hainisch EK, Brandt S.Horses and other equid species are frequently affected by bovine papillomavirus type 1 and/or 2 (BPV1, BPV2)-induced skin tumors termed sarcoids. Although sarcoids do not metastasize, they constitute a serious health problem due to their BPV1/2-mediated resistance to treatment and propensity to recrudesce in a more severe, multiple form following accidental or iatrogenic trauma. This review provides an overview on BPV1/2 infection and associated immune escape in the equid host and presents early and recent immunotherapeutic approaches in sarcoid management.
Miller MM, Sweeney CR, Russell GE, Sheetz RM, Morrow JK.To determine effects of blood contamination on western blot (WB) analysis of CSF samples for detection of anti-Sarcocystis neurona antibodies, and on CSF albumin and IgG concentrations, albumin quotient (AQ), and IgG index in horses. Methods: Prospective in vitro study. Methods: Blood with various degrees of immunoreactivity against S neurona was collected from 12 healthy horses. Cerebrospinal fluid without immunoreactivity against S neurona was harvested from 4 recently euthanatized horses. Methods: Blood was serially diluted with pooled nonimmunoreactive CSF so that final dilutions correspon...
House JA.AHS is a noncontagious vector-borne disease of Equidae caused by Orbiviruses. Species susceptibility in decreasing order is horses, mules, donkeys, and zebras. The main vectors of AHS are culicoides. The disease is endemic in sub-Saharan Africa, but epizootics have occurred outside of this area on several occasions. The most recent outbreaks outside of the endemic area were in Spain, Morocco, and Portugal between 1987 and 1990. AHS causes mortality up to 95% and is classically divided into four clinical forms: the pulmonary, cardiac, mixed, and horse fever forms. Pathologic changes are subcuta...
Teifke JP, Weiss E.Unfixed and formalin-fixed frozen sections and paraffin-sections of histopathologically confirmed sarcoids of 20 horses were studied in the PCR. The used set of primers was located in the E5 open reading frame fitting both to bovine papillomavirus 1 (BPV-1) and BPV-2. Independent of the quality of the used tissues BPV-DNA was detected in all 20 sarcoids. By cleaving with restriction endonuclease Bst XI it was shown that the DNA-sequences amplified by PCR were identical with that of BPV-1. The results support the general view that BPV play an important role in equine sarcoids.
Zintl A, Westbrook C, Mulcahy G, Skerrett HE, Gray JS.In order to explore the feasibility of producing a Babesia divergens live vaccine free of bovine material contaminants the parasite's ability to grow in human, sheep and horse erythrocytes and serum and serum-free medium was investigated. B. divergens was successfully maintained in bovine erythrocytes overlaid with serum-free HL-1 medium. Supplementation of the culture medium with bovine or sheep serum improved parasite growth (monitored by measuring parasitaemia and uptake of tritiated hypoxanthine) whereas horse and human sera reduced parasite growth. As assessed by Giemsa's stained and FITC...
Erdemsurakh O, Ochirbat K, Gombosuren U, Tserendorj B, Purevdorj B, Vanaabaatar B, Aoshima K, Kobayashi A, Kimura T.Glanders is a contagious and fatal equine disease caused by the gram-negative bacterium Burkholderia mallei. B. mallei is prevalent among horse populations in Asia, the Middle East, and South America. More than four million horses have been registered in Mongolia in 2020. However, the recent prevalence of glanders has not been well investigated. In this study, we aimed to investigate the seropositivity of B. mallei in horse populations in Mongolia using the complement fixation test (CFT) and Rose Bengal plate agglutination test (RBT). We randomly collected blood samples from horses in central ...
Falcão MVD, Silveira PPM, Santana VLA, da Rocha LO, Chaves KP, Mota RA.Burkholderia (B.) mallei is the causative agent of glanders in Equidae. This study describes the first record of the Turkey 10 strain of B. mallei in glanderous horses in Northeastern of Brazil. This description should contribute to the future actions of diagnosis, control, and eradication of this disease in Brazil.
Bedenice D, Johnson AL.EPM, CVSM, and EDM are currently recognized as the 3 most common neurologic diseases in US horses, with the latter 2 conditions being most prevalent in young animals. Moreover, horses competing at shows and performance events are at greater risk for exposure to highly contagious, neurologic EHV-1 outbreaks. A clinical diagnosis of any neurologic disease should be based on a careful history, complete neurologic examination, and appropriate diagnostic testing and interpretation. However, mild or early neurologic signs can often mimic or be mistaken for an orthopedic condition when horses present...
Rushton JO, Kolodziejek J, Nell B, Nowotny N.The aim of this study was to assess the extent of asinine herpesvirus (AsHV) type 5 infection in 'closed' populations of clinically normal Lipizzaner horses. Peripheral blood mononuclear cells plus nasal and conjunctival swabs were obtained on four occasions over an 18 month period from 266 animals as part of a health surveillance programme. Sequence analysis of samples that were positive by nested consensus herpesvirus PCR but negative using quantified equid herpesvirus (EHV) type 2 and 5 PCR, revealed a total of 51 samples from 39 horses positive for AsHV-5. No statistically significant asso...
Wong KS, Cheung HW, Szeto CWL, Tsang CYN, Wan TSM, Ho ENM.Illicit administration of transgene into horses is a form of gene doping that has been a key concern in equine sports. The large number of potential performance-enhancing transgenes has demanded a cost-effective and reliable detection method. Multiplex qPCR is a relevant technique, but the cross-talking between fluorophores and high background noise limits the method sensitivity and specificity. This study reports a simpler multiplexing approach by using the same fluorophore for four hydrolysis probes each targeting one of the four transgenes: human growth hormone, insulin-like growth factor 1...
Clode AB.The following article briefly discusses the pathogenesis of infectious keratitis in the horse, followed by discussion of management and pharmacological aspects to be considered when devising a therapeutic protocol for affected patients.
Xiao L, Herd RP.Diarrhoea is one of the most important diseases of foals and
7040% are affected within the first 6 months of life (Palmer
1985). Although the cause is multifactorial and changes in the
physiology and nutrition of foals are sometimes responsible,
diarrhoea is frequently the result of infection by enteropathogens
such as bacteria, viruses and nematodes (Palmer 1985; Tzipori
1985). There is increasing evidence that Cryptosporidium
infection can also cause diarrhoea in foals (Austin et a/. 1990;
Kim 1990).
Cryptosporidiosis in horses is caused by Cryptosporidium
parvum, a coccidial paras...
Selim SA, Soliman R, Osman K, Padhye AA, Ajello L.Isolation of Histoplasma farciminosum from five horses, showing typical signs of histoplasmosis farciminosi (epizootic lymphangitis) was successfully attempted. The mycelial form of H. farciminosum was isolated on Sabouraud dextrose agar enriched with 2.5% glycerol, brain heart infusion (BHI) agar enriched with 10% horse blood and PPLO dextrose glycerol agar. The last medium proved to be the most effective, both for primary isolation and subculturing of the fungus. It was found that on primary isolation, the lag phase of the mycelial form of the fungus was relatively long, involving 4-8 weeks ...