Pathogens are microorganisms, such as bacteria, viruses, fungi, and parasites, that can cause disease in horses. These microorganisms interact with the equine immune system, often leading to a range of health issues that can affect individual horses or entire populations. Pathogens can be transmitted through various routes, including direct contact, vectors, or environmental exposure. Common equine pathogens include Streptococcus equi, Equine Herpesvirus, and Strongylus vulgaris. Understanding the interactions between equine hosts and pathogens is essential for disease prevention, management, and treatment. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, transmission, and impact of pathogens on equine health.
Parker JT, McCoy MV.1. The serum of horses immunized with increasing doses of certain anaerobically produced autolysates of pneumococci contain potent neutralizing antibodies for the pneumotoxin. 2. The method for the in vitro titration of these horse antipneumotoxic serums is given.
Wadsworth AB, Sickles GM.IT HAS BEEN SHOWN THAT THE PNEUMOCOCCUS MULTIPLYING IN THE TISSUES OF THE IMMUNIZED ANIMAL (HORSE) BECOMES ATTENUATED: loses, in varying degrees, its virulence, capacity of capsule formation, susceptibility to phagocytosis, and type specificity. The antigenic activity as an immunizing agent and the production of "soluble specific substance" are also altered. In some instances, the typical pneumococcus characteristics may be quickly restored by one or two passages through a susceptible animal (mouse). In others, virulence is not recovered and the organism remains atypical. Whether these changes...
Olitsky PK, Kligler IJ.With the methods which have been described we have separated an exotoxin and an endotoxin from cultures of the Shiga dysenteric bacillus. The study of the nature and effect of the poison of this microorganism is thus simplified. The two toxins are physically and biologically distinct. The exotoxin is relatively heat-labile, arises in the early period of growth, and yields an antiexotoxic immune serum. The endotoxin, on the other hand, is heat-stable, is formed in the later period of growth, and is not neutralized by the antiexotoxic serum. The exotoxin exhibits a specific affinity for the cent...
Jones FS.The lower nasal mucosa and the pharynx of thirty eastern and twenty-three western horses have been examined for streptococci. Eight of the eastern horses carried non-hemolytic streptococci on the nasal mucosa. From the pharynx of six, non-hepiolytic streptococci were cultivated. The throats of eighteen contained strains of the hemolytic type. The nasal mucosa of the eastern horses failed to show hemolytic streptococci. Eight western horses carried non-hemolytic streptococci in the nasal passage; eight also harbored the hemolytic type. Twenty-two strains were isolated from the pharynx. Eleven w...
Wollstein M.The parameningococci of Dopter are culturally indistinguishable from true or normal meningococci, but serologically they exhibit differences as regards agglutination, opsonization, and complement deviation. Because of the variations and irregularities of serum reactions existing among otherwise normal strains of meningococci it does not seem either possible or desirable to separate the parameningococci into a strictly definite class. It appears desirable to consider them as constituting a special strain among meningococci not, however, wholly consistent in itself. The distinctions in serum rea...
The primer set for 16S rDNA amplified an amplicon of about 1500 bp in length for three strains of Taylorella equigenitalis (NCTC11184(T), Kentucky188 and EQ59). Sequence differences of the 16S rDNA among the six sequences, including three reference sequences, occurred at only a few nucleotide positions and thus, an extremely high sequence similarity of the 16S rDNA was first demonstrated among the six sequences. In addition, the primer set for 16S-23S rDNA internal spacer region (ISR) amplified two amplicons about 1300 bp and 1200 bp in length for the three strains. The ISRs were estimated to ...
Narouei M, Rahimi H, Kafshdouzan K.Infections caused by and , as zoonotic diseases, pose a serious threat to the health of humans and animals. To date, there is limited information regarding these diseases in horses. This study aimed to evaluate the prevalence of and in the serum of racehorses in Iran (Golestan province). 350 blood samples were collected from racehorses in four regions of Golestan province, and demographic data (sex, age, and sampling location) were recorded. The collected serum samples were examined by PCR to identify the genomes of and . The results showed that 3.4 % (P < 0.05, 95 % CI: 1.97 % - 5.9 %) of...
Harel B, Sévin C, Le Hello S, Moreau P, Giard JC, Petry S, Gravey F.Enterobacteriaceae are opportunistic pathogens responsible for local or systemic infections in both human and veterinary medicine. To monitor circulating strains in stud farms in Normandy (France), we investigated a collection of Enterobacteriaceae isolated from necropsied equids performed in the region between 1997 and 2020. These strains were initially identified using MALDI-TOF; however, as this method failed to identify some isolates, whole genome sequencing followed by rMLST analysis was subsequently performed. Different genera were identified: Enterobacter spp., Huaxiibacter spp., Lellio...
Mota RA, Silito IS, Martins MP, Oliveira PRF, Melo RPB, Vieira da Silva V, Jorge FR, Martins TF, Labruna MB.Tick-borne diseases are among the most widespread vector-borne infections, including zoonoses caused by bacterial and protozoal microorganisms. This study consisted of a serosurvey for Rickettsia spp. in 270 horses from 11 farms in the coastal region of Pernambuco, Brazil. Through the indirect immunofluorescence assay (IFA) based on antigens of five Rickettsia species, 164 (60.7%) horses were seroreactive to Rickettsia spp., with seroreactivity among farms ranging from 10 to 100%. Through molecular analysis, all 270 horse blood DNA samples tested negative by PCR assays targeting Anaplasmatacea...
Werle J, Nunes GT, Machado CS, Silva CBD, Vogel FSF, Vargas APC, Cargnelutti JF.The genus Corynebacterium encompasses versatile bacteria that act as natural microbiota or pathogens, causing infections in humans and animals, including equine reproductive disorders. Corynebacterium uterequi (C. uterequi) is a potential pathogen in mares, associated with reproductive disorders including endometritis, embryonic loss, and infertility, raising concerns for equine reproductive health. This study aimed to characterize C. uterequi isolates from mares in southern Brazil and deepen the understanding of this species. Phenotypic, molecular, and phylogenetic analyses were performed on ...
Snedden K, Frye E, Conklin R, Aprea M, Rishniw M, Lejeune M, Goodrich E.To analyze the results and metadata of canine, feline, and equine respiratory PCR panel assays performed at the New York State Animal Health Diagnostic Center and inform veterinary diagnostic sample submission. Unassigned: This retrospective study reviewed laboratory data from routine sample submissions to the Animal Health Diagnostic Center for canine, feline, and equine respiratory PCR panels from January 1 through December 31, 2023. Associations were compared between variables using χ2 tests of independence or Fisher exact tests. Unassigned: A total of 1,902 canine, feline, and equine resp...
Nakajima K, Kasuya K, Senba H, Tagami K, Kinoshita Y, Niwa H.Strangles is a globally widespread, commonly diagnosed and important infectious disease of equids caused by Streptococcus equi subsp. equi. We performed whole genome sequencing of 19 S. equi isolates collected from imported horses at the Japanese border. Of these isolates, 15 isolates were obtained from clinical cases and 4 were from subclinical cases. The 19 isolates were grouped into 3 Bayesian analysis of population structure (BAPS) groups by the core genome single nucleotide polymorphism analysis corresponding to exporting country, SeM typing, or exporter of the horses. The 19 isolates pos...
Hu B, Gao S, Zhang H, Li Q, Li G, Zhang S, Xing Y, Huang Y, Han S, Tian Y, Zhang W, He H.Rhodococcus equi (R. equi) is a Gram-positive zoonotic pathogen that frequently leads to illness and death in young horses (foals). This study presents the complete genome sequence of R. equi strain BJ13, which was isolated from a thoroughbred racehorse breeding farm in Beijing, China. Results: The BJ13 genome has a length of 5.30 Mb and consists of a complete chromosome and a plasmid measuring 5.22 Mb and 0.08 Mb, respectively. We predicted 4,929 coding gene open reading frames, along with 52 tRNAs and 12 rRNAs. Through analysis of mobile genetic elements, we identified 6 gene islands and ...
Molazadeh S, Tukmechi A, Hadian M, Dalir-Naghadeh B.This study aimed to determine the prevalence and phylogenetic analysis of Ehrlichia spp. in horses and dogs in Iran. Blood samples were collected from 400 animals, including 200 horses and 200 dogs, from five different provinces in Iran. Polymerase chain reaction (PCR) was used to detect Ehrlichia spp. based on amplification of the 16S rRNA gene. The semi-nested PCR method was used to amplify the dsb, TRP36, and gltA genes. The results showed that 4.5 % of the samples (3 % horses and 6 % dogs) were positive for Ehrlichia sp. The highest prevalence was observed in Kerman and Khuzestan, while th...
Silva-Ramos CR, Niño Rodríguez JA, Gil-Mora J, Betancourt-Ruiz P, Martínez-Díaz HC, Forero-Becerra E, Matiz-González JM, Bolaños E, Olaya-M LA....Babesia species are tick-borne protozoan parasites which affect several animal species. Babesia spp. infections are significantly important for veterinary medicine, affecting a wide range of domestic animal species such as dogs, cattle, and horses. In Colombia, studies of Babesia spp. infections in domestic animals are scarce. Thus, the aim of the present study was to explore the circulation of these parasites among domestic canines, bovines and equines from the department of Cauca. Methods: Between August and November, 2017, active domestic animal sampling of cattle was performed in eight rur...
Eissa N, Salman MB, Younes AM, Mohamed ESA, Abu-Seida AM, Abdulkarim A, Zin Eldin AI.Worldwide, zoonotic diseases represent serious risks to public health, underscoring the need for efficient surveillance techniques. The One Health concept has gained popularity as a comprehensive paradigm for tackling zoonotic disease surveillance because it acknowledges the correlation of pathogens, animals, humans, and the surrounding environment. Public health is now concerned about antibiotic-resistant (), which causes severe impurities in animals and humans, leading to morbidity and mortality. Unassigned: This study examined the collaborative efforts between human and animal (cattle and ...
Azócar-Aedo L, Meniconi G, Pino-Olguín C, Gallardo M.At a veterinary hospital in southern Chile, we conducted an epidemiological study involving domestic dogs, cats, and horses to determine the seropositivity for pathogenic spp., identify the infecting serogroups, measure antibody titers, and characterize seropositive animals by sex and age. None of the sampled animals showed clinical signs of leptospirosis. The microscopic agglutination test, using a panel of eight serogroups, was used for diagnosis. The seropositivity was 36.5% (95% confidence interval [CI] = 24.5-48.4) in dogs, 12.9% (95% CI = 2.6-23.1) in cats, and 45.2% (95% CI = 30.1-60.2...
Montini M, Torrents J, Nava S, Sebastian PS. ticks collected on horses from the North-West of Argentina were analyzed for the presence of the Piroplasm agents and . A total of 97 adult ticks from four different provinces (Jujuy, Santiago del Estero, Salta, Tucumán) were included in this study. Genomic DNA was isolated, and conventional PCR assays were applied for the detection of the 18S rDNA gene of and species. One sample corresponding to a male of collected in Tapia, Tucumán Province, resulted positive. Phylogenetic analyses carried out with the obtained 18S rDNA partial gene sequences resulted in the identification of . Althou...
Cain JL, Norris JK, Swan MP, Nielsen MK.The microbiome plays an important role in health, where changes in microbiota composition can have significant downstream effects within the host, and host-microbiota relationships can be exploited to affect health outcomes. Parasitic helminths affect animals globally, but an exploration of their microbiota has been limited, despite the development of anti-Wolbachia drugs to help control infections with some filarial nematodes. The equine ascarids, Parascaris spp., are considered the most pathogenic nematodes affecting juvenile horses and are also the only ascarid parasite to have developed wi...
Sousa JA, Miranda LM, Coutinho DJB, Costa TF, Costa SP, Freitas ÚS, Costa FB, Machado RZ, Nogueira RMS, Costa APD.The hemoprotozoan Trypanosoma evansi is a parasite that infects mammals, causing an infection known as trypanosomiasis. There is no report of T. evansi in horses in the State of Maranhão, highlighting the need to assess exposure and infection by the parasite and generate data for its monitoring. The objectives of this study were to identify T. evansi in blood samples from horses, investigate its occurrence in horses in this region, and analyze the associated risk factors. Three hundred blood samples were collected for parasitological (blood smear), serological (indirect enzyme-linked immunoso...
de Albuquerque CV, da Silva Andrade M, de Freitas MS, Paulino PG, Santos HA, de Tarso Landgraf Botteon P.Equine Piroplasmosis (EP) and Equine Granulocytic Anaplasmosis (EGA) are diseases that affect horses, transmitted by ixodid ticks, causing a nonspecific febrile syndrome. Equine Piroplasmosis is endemic in Brazil, and most horses are in enzootic stability. Serological and molecular studies carried out on horses in Brazil have shown the presence of Anaplasma phagocytophilum, however, the clinical relevance of this infection has not yet been established. The present study aims to evaluate the importance of Babesia caballi, Theileria equi, and A. phagocytophilum as etiological agents in horses wi...
