Equids are members of the family Equidae, which includes modern horses, donkeys, and zebras, as well as extinct species. Equids are characterized by their long limbs, single-toed hooves, and herbivorous diet, which is primarily composed of grasses. Horses, specifically, have been domesticated for thousands of years and have played significant roles in agriculture, transportation, and sport. This page compiles peer-reviewed research studies and scholarly articles that explore various aspects of equids and horses, including their evolution, physiology, behavior, and interactions with humans. The collected works provide insights into the genetic diversity, adaptive traits, and conservation efforts related to equid species.
Klass LG, Diekmann I, Andreotti S, Mbedi S, Sparmann S, Schenk T, Anderson HP, Bellaw J, Nielsen MK, Krücken J, von Samson-Himmelstjerna G.Strongyles, especially non-migratory Strongylidae, are the most common equine gut parasites, and typically occur in mixed infections with 10 - 20 species per host. Current knowledge on strongyle species prevalence and within-host tropism is sparse. Herein species composition of mixed strongyle infections of 12 naturally infected untreated young horses, based on strongyle eggs extracted from faeces, cultured third stage larva and luminal worms collected from ventral and dorsal colon was examined. Species were identified using a cytochrome c oxidase I (COI) metabarcoding approach allowing differ...
Klopfenstein Bregger MD, de Preux M, Brünisholz HP, Van der Vekens E, Schweizer D, Koch C.This retrospective case series reports on the use of computer-assisted surgery (CAS) to perform cheek tooth repulsion in 16 equids. Thirteen of the 16 subjects in this case series had a mandibular cheek tooth repulsed, and 3 had a maxillary cheek tooth removed. Surgery was performed on all subjects under general anesthesia, and all but one were placed in lateral recumbency. All cheek teeth were successfully removed by navigated repulsion, except in one case where additional intraoral sectioning was performed. In one horse, a surgical approach through the contralateral nasal conchae was made to...
Frippiat T, Bonhomme M, Dyson S, Votion DM.Equine gastric ulcer syndrome (EGUS) adversely affects the health, welfare, and performance of sports horses, requiring gastroscopy for definitive diagnosis. Owners frequently consider girth aversion as highly suggestive of EGUS. Objective: To evaluate whether owner-reported clinical signs or fecal occult blood tests (FOBTs) can help identify horses needing gastroscopy for EGUS diagnosis or monitoring treatment, thereby reducing unnecessary procedures in unaffected horses. Methods: Eighty competition dressage horses referred by veterinarians for EGUS evaluation. Methods: Case-control study in...
Kambayashi Y, Bannai H, Nemoto M, Kawanishi N, Niwa H, Tsujimura K.With the revision of the World Organisation for Animal Health (WOAH) Terrestrial Manual on equine rhinopneumonitis in 2024, 3 recommended qPCR primer-probe sets were added for the detection of equid alphaherpesvirus 1 (EqAHV1; formerly equine herpesvirus 1 [EHV1]; family , taxon species ), also known as equine abortion virus. We compared the sensitivity and specificity of the 3 qPCR primer-probe sets to determine the most reliable set. Sets gB1H and gB1P, which target the glycoprotein B () gene of EqAHV1, detected all 10 copies and even lower copy numbers. In contrast, set gC1 (ISO 17025-accre...
Barbosa B, Santi TF, Rodak AC, Nogara MF, Leite LMB, Weber SH, Niels C, Daros RR, Michelotto PV.The analysis of equine exhaled breath condensate (EBC) lacks standardized methodology, and current collection devices are often adapted for research. This study evaluates a novel horse-specific EBC collector and assesses the variability of EBC pH and hydrogen peroxide (HO) levels, exploring potential correlations with bronchoalveolar lavage (BAL) and tracheal wash (TW) cytology. Eleven healthy mixed-breed mares from a teaching herd, with no evidence of airway abnormalities, were included in this randomized observational study. The collection efficiency of the proposed device was assessed, and ...
Parmantier S, Kyriazopoulou P, McClendon M, Adams A, Murphy BA.Fifty-two horses aged >15 years, diagnosed with pituitary pars intermedia dysfunction (PPID), and displaying hypertrichosis were recruited via an online survey of PPID horse owners. From mid-December, group T ( = 29) wore Equilume light masks extending photoperiod to 15 h daily, while group C1 ( = 23) remained under natural photoperiod. As 85% (44/52) of recruited study horses received pergolide medication, a second unmedicated PPID research herd (C2; = 17) was recruited and remained under natural photoperiod. Hair coat samples, shedding and body condition scores were collected monthly by own...
Krücken J, Diekmann I, Andreotti S, Bredtmann CM, Mbedi S, Sparmann S, Schmidt JS, de Almeida Borges F, de Freitas MG, Sallé G, Hofer H....Equines are parasitized by complex communities of Strongylidae (Nematoda) comprising multi-species infections. Currently, Cyathostominae are most prevalent, while Strongylus species are only rarely detected. Since eggs and, in most cases, infective larvae cannot be differentiated to species level, except for Strongylus spp., species-specific knowledge of the pathology, epidemiology and ecology of these parasitic nematodes is limited. Reference sequence data for several cyathostomin species are limited or missing. Deep amplicon sequencing of internal transcribed spacer 2 (ITS-2) regions of nema...
Yamashita N, Hatazoe T, Misumi K, Hobo S.The Tokara horse is a breed of native Japanese horse, for which hematological and biochemical data are lacking. The aim of this study was to obtain current hematological and biochemical data on Tokara horses. We enrolled 90 Tokara horses kept at the Kaimon Foothills Nature Park (Kagoshima) that underwent physical examinations and blood sampling between 2022 and 2024. All horses in this study were regarded as clinically healthy, based on physical examinations. Hematological and biochemical parameters also showed no abnormal values. Based on the above results, we consider that the data from this...
Ren W, Zhou J, Zhu J, Zhang J, Zhao X, Yao X.The ovary is among the earliest organs to undergo age-related degeneration, limiting the reproductive potential of elite horses and constraining the growth of the equine industry. Follicular development during estrus is a key determinant of fertility, yet the molecular mechanisms underlying its decline, particularly at the level of specific ovarian cell types, remain poorly understood in equids. Here, we constructed a single-cell transcriptomic atlas to investigate ovarian changes in Kazakh horses. Using single-cell RNA sequencing (scRNA-seq), we profiled 112,861 cells from follicle-containing...
Rodero E, González-Martínez A, Diz A, Rodero J.One of a veterinarian's routine tasks is animal identification, with age being a crucial factor in the identification and evaluation of individuals. Knowledge of the morphological changes in animal dentition used to determine their age is essential in veterinary education. Today's students increasingly prefer innovative learning tools that incorporate 3D anatomical models over traditional 2D resources. As part of a teaching innovation project at the University of Córdoba, Spain, new educational materials were developed to aid students in identifying the age of animals using 3D images of equin...
McLinden LA, Kemp-Symonds JG, Daly JM, Blanchard AM, Waller AS, Freeman SL.Infection with Streptococcus equi subspecies equi (S. equi) is characterised by acute disease, with about 10% of infected animals remaining persistently infected. Clinically, infection with S. equi cannot readily be distinguished from infection caused by other respiratory pathogens, including Streptococcus equi subspecies zooepidemicus (S. zooepidemicus), equine influenza virus, and equine herpes virus. Screening protocols, with appropriate quarantining facilities, are important to detect horses infected with S. equi and avoid strangles outbreaks. Virulent strains of S. zooepidemicus can also ...
Kamiya U, Kakiuchi K, Kawamura K, Ueda K, Kawai M, Matsui A, Negishi N.Accurate monitoring of grazing behavior in horses is essential for pasture management and welfare evaluation; however, conventional observation methods are labor-intensive and lack temporal resolution. Objective: This pilot study aimed to develop and validate a deep learning model using jaw-mounted accelerometer data to classify grazing and non-grazing behaviors in yearling horses under various pasture conditions. Methods: Four yearling Thoroughbred horses were equipped with triaxle accelerometers mounted under their jaws. Data were recorded at 10 Hz (100 ms) during a 19 h free-grazing period ...
Woodman MJ, Thomas MA, Colville MJ, Durgam S, McDonough SP, Reesink HL.To describe proteoglycan 4 (PRG4) expression, lubricin tissue distribution, and lubricin synovial fluid concentrations in healthy and injured equine flexor tendons and tenosynovial structures. Unassigned: Synovial fluid and tissues were collected over the span of 1 year. Proteoglycan 4 expression was quantified using quantitative real-time PCR, lubricin synovial fluid concentrations were measured using ELISAs, and lubricin tissue distribution was evaluated with immunohistochemistry. Histology and quantitative real-time PCR data for healthy samples were analyzed using paired t tests, repeated-m...
Weingarten A, Häusler M, Serangeli J, Verheijen I, Reiter E, Radzevičiūtė R, Stoessel A, Krause J, Spyrou MA, Conard NJ, Nieselt K, Posth C.Deep-time palaeogenomics offers rare insights into macroevolutionary events for both extant and extinct species. Aside from a Middle Pleistocene genome from North American permafrost (780-560 ka) and a number of Late Pleistocene specimens, most ancient horse DNA studies have focused on tracing the origins of domestication and subsequent periods. Here we present mitochondrial genomes from two Equus mosbachensis specimens from Schöningen, Germany, a Middle Pleistocene archaeological site complex with direct and repeated evidence of hominin-horse interactions on the shore of a palaeolake. Usin...
Koshy SA, Ajeebsanu MM, Karakka Kal AK, Subhahar MB, Karatt TK, Philip M.Effective pain management remains a persistent challenge, with opioids limited by tolerance, dependence, respiratory depression, and misuse. This has created demand for safer, nonaddictive alternatives. Suzetrigine (VX-548, Journavx) is a novel analgesic with promising efficacy, but its potential misuse in competitive racing requires investigation. Limited information is available on its metabolism and detection, emphasizing the need for metabolic characterization to aid antidoping strategies. Methods: In vitro metabolism of suzetrigine was evaluated using equine liver microsomes and homogeniz...
Šarkūnas M, Schwahn A, Suleimanova K.The aim of present study was to examine the potency of moxidectin solution (Cydectin 1 %; Zoetis) and commercially available oral moxidectin gel (Equest®; Zoetis) to suppress the excretion of strongyle eggs in horses over a 6-week period. The horses naturally infected with strongyle nematodes (>500 eggs/g of feces) were divided into two comparable groups according age, sex and weight. On day 0 of the study, horses in Group OT (oral treatment; N=5) were dewormed with moxidectin gel (Equest®; Zoetis; 0.4 mg/kg of b.w.) according to the manufacturer's instructions, and horses in Group IT (intra...
Vasconcelos AB, França DA, Prado ACD, Yamauchi DH, Silva ACAD, Barros IO, Valença SRFA, Lucheis SB, Bosco SMG.Pythiosis is an underestimated and neglected disease in Brazil, both in horse breeders and in horses. The molecular detection of in horses in the Brazilian Northeast represents a milestone in the epidemiology of equine pythiosis in the country. This study reports novel cases of equine pythiosis, diagnosed by molecular methods, in five states of Northeastern Brazil. Clinical samples were submitted to microbiological culture, DNA extraction, and nested-PCR for molecular detection of . The nested-PCR successfully detected in four out of five equine lesion samples, demonstrating higher sensitivi...
Ralletti MV, Meistro F, Tarasconi MA, Mandrioli L, Renzi A, Rinnovati R, Spadari A.Extraskeletal chondromas (ESCs) are rare benign tumours composed of mature cartilage that typically develop in soft tissues. Their occurrence in horses is extremely uncommon and, to the authors' knowledge, no previous cases of lingual ESCs in equines have been reported. This report describes a two-year-old Quarter Horse colt presented with progressive dysphagia. Clinical examination revealed a solitary, multilobulated, firm-elastic mass located at the dorsal aboral portion (base) of the tongue. Diagnostic imaging ruled out bone involvement. The mass was surgically excised under general anaesth...
Dumičić I, Ostojić L.Like other domesticated species, most notably dogs, horses have been reported to follow human gestures and successfully use them to gain rewards in an object choice task. Empirical support for the hypothesis that a domain-general mechanism may underlie this ability comes from studies in which horses have successfully solved the task by using not just a human pointing gesture but also an arbitrary physical cue, namely a wooden marker. Here, we replicated the two conditions in which these two cues were used by Proops et al. (2010) with two critical changes: first, we positioned the marker out of...
Scala E, Durie I, Gommeren K, Saegerman C, van Galen G.(1) Background: Ultrasonography of major vessels helps evaluate fluid status and responsiveness in critical human and canine patients. Aims: transrectal and inguinal ultrasonography of caudal vena cava (CVC), aorta (Ao), and femoral artery (FA) and vein (FV) in horses; calculate CVC collapsibility index (CI CVC) and vein-to-artery ratios; compare B- and M-mode; and evaluate repeatability and reproducibility. (2) Methods: B-mode and M-mode video loops were recorded twice by transrectal (Ao, CVC) and inguinal ultrasonography (FV, FA) by two operators on 17 healthy, sedated adult horses. Diameter...
Mège M, Bonsergent C, Viry L, Dhune M, Lecollinet S, Malandrin L.Equine piroplasmosis is a major tick-borne horse disease, caused by the intracellular development of piroplasms (Theileria equi sensu lato and Babesia caballi), with significant economic and sanitary consequences. In 2024, 203 blood samples were collected in Guadeloupe (Caribbean) from asymptomatic horses. Using an 18S rRNA nested PCR (nPCR) specific for each equine genus parasite, 79 samples tested positive for Theileria equi and 9 for Babesia caballi, resulting in respective prevalence of 38.9% and 4.4%. Three horses were co-infected. For B. caballi, 18S rRNA sequence analysis revealed the p...
Studzińska M, Klockiewicz M, Szczepaniak K, Demkowska-Kutrzepa M, Roczeń-Karczmarz M, Tomczuk K.The resistance of strongyles to pyrantel pamoate has been reported in publications worldwide. There is no data on its efficacy in horses in Poland. Therefore, the aim of this study was to evaluate the effectiveness of pyrantel pamoate to control strongyle invasions in young horses. The study involved horses of both sexes, aged 1 to 2 years, and was conducted in two seasons (spring and the end of summer). Feces were collected 24 hours before and 14 days after deworming, and they were then examined using McMaster's and combined sedimentation-flotation methods. Results revealed that in spring, th...
Djellouli M, Eddaikra N, Beneldjouzi A, Benikhlef R, Ghimire R, Wilkins M, Lafri I.Cutaneous leishmaniosis remains a major public health concern in Algeria, predominantly affecting humans and dogs. However, the role of other animal hosts, particularly equids, in the transmission cycle remains underexplored. This cross-sectional study presents the first systematic investigation of Leishmania spp. exposure and infection in equids, along with associated environmental and host factors, from southeastern Algeria, El Oued Wilaya, the third most affected region for human cutaneous leishmaniasis in the country. A total of 122 equids from eight communes were clinically examined and t...
Wilson KE, Davis JL.Adverse drug events (ADEs) are any harms caused by medical interventions used for treatment, prevention, or diagnosis. These events can happen due to human error or as unintended, harmful reactions to drugs when given at normal therapeutic doses. This review focuses on common ADEs associated with drugs frequently used in equine practice. Recognizing and understanding the manifestations of ADEs can help with early detection and more effective management, ultimately leading to better outcomes for equine patients. Additionally, knowledge of the potential harmful effects of drugs also aids in appr...
Countrymann K, Ruby R, Miller AD.Equine meningoencephalomyelitis is an important cause of morbidity and mortality and is associated with a wide variety of infectious etiologies. Because of the lack of large retrospective studies, the prevalence and incidence of these diseases are unknown. Here we describe 171 cases of meningoencephalomyelitis in horses submitted to the Section of Anatomic Pathology at the New York State Animal Health Diagnostic Center (Cornell University, Ithaca, NY, USA) from 1996-2023. Neuroinflammatory disease was identified in 5.4% of submitted horses with a wide breed, age, and sex distribution. A parasi...
Luštrek B, Šimon M, Turk K, Bogičević S, Potočnik K.In small, closed populations such as the Lipizzan horse, maintaining genetic diversity while limiting inbreeding is a key challenge in conservation breeding. The Lipizzan is an indigenous Slovenian breed with a small population and restricted gene flow from other subpopulations. Inbreeding is traditionally monitored with pedigree-based coefficients, but these often underestimate realised autozygosity, particularly when pedigree depth is limited. This study compared pedigree-based inbreeding (F_PED) with four genomic estimators (F_HOM, F_ROH, F_HBD, F_GRM) in 329 Slovenian Lipizzan horses genot...
Wang J, Li Z, Li L, Wang R, Ma S, Su Y, Shan D, Huang Q.Kazakh horses are renowned for their endurance and adaptability, with distinct muscle groups such as the longissimus dorsi (LD) and biceps femoris (BF) muscles serving specialized functions. However, the molecular mechanisms underlying the functional specialization of these muscles in Kazakh horses remain poorly understood. This study aims to address this gap by utilizing single-cell RNA sequencing (scRNA-seq) to investigate the transcriptomic differences between these muscle groups, with a focus on understanding their molecular adaptations. Our analysis revealed that the BF muscle, specialize...
Brauns M, Ali A, Berger J, McLean A.Small stalls and regulated feedings restrict horses' natural foraging and locomotion, increasing risks to welfare. Environmental enrichment may promote more naturalistic behavioral time budgets, yet little is known about how enrichment type or timing affects physiology and behavior. This study examined nine stabled Quarter Horses provided with hay feeders, activity balls, or mirrors across randomized trials. Each trial included 30 min observations, four times per day, with enrichment removed between sessions and 5-day washouts between trials. Nightwatch Smart Halters™ recorded heart and resp...
Wang T, Yang X, Wang C, Wang J, Meng J, Yao X, Zeng Y, Ren W.Studying the genetic characteristics and molecular mechanisms of immune regulation in horses is of great significance for protecting their genetic resources, improving breeding strategies, and enhancing their disease resistance, thereby ensuring their healthy performance in both sports and production. Objective: This study investigates the genetic characteristics and molecular mechanisms underlying immune regulation in Yili horses, comparing them with Thoroughbreds and Kazakh horses. Methods: Blood samples from each breed were analyzed for physiological, biochemical, and immune indices alongsi...
Dugdale AH, Curtis GC, Milne E, Harris PA, Argo CM.Excessive accumulations or depletions of body fat have been associated with increased morbidity and mortality in horses and ponies. An objective, minimally-invasive method to accurately quantify body fat in living animals is required to aid nutritional management and define welfare/performance limits. Objective: To compare deuterium oxide (D(2) O) dilution-derived estimates of total body water (TBW) and body fat with values obtained by 'gold standard' proximate analysis and cadaver dissection. Objective: D(2) O dilution offers a valid method for the determination of TBW and body fat in equids....
Magnarelli LA, Anderson JF, Shaw E, Post JE, Palka FC.During 1982 and 1985, blood samples from 705 equids were examined for antibodies to Borrelia burgdorferi. By indirect immunofluorescence staining, IgM and total immunoglobulin (IgM and IgG) antibodies were detected in 37 (5.3%) and 90 (12.8%) serum specimens, respectively. The geometric mean titer for IgM antibody (140.4) was highest during July, whereas total immunoglobulin ranged from 94.1 in October to 338 in May. Eighty-six equids with total immunoglobulin to B burgdorferi lived in areas of Connecticut where the primary tick vector, Ixodes dammini, was present. Of the 86 equids, 9 from Lym...
Hussain MH, Saqib M, Raza F, Muhammad G, Asi MN, Mansoor MK, Saleem M, Jabbar A.Equine piroplasmosis (EP) caused by intraerythrocytic parasites (Theileria equi and Babesia caballi) is an emerging equine disease of world-wide distribution. In Pakistan, the prevalence and incidence of EP are unknown. In order to obtain the first insights into the prevalence of the disease, a total of 430 equids, including 33 mules, 65 horses and 332 donkeys, aging from ≤ 5 to ≥ 10 years of either sex, from five metropolises of Punjab, Pakistan, were serologically tested for the presence of antibodies directed against B. caballi and T. equi, using a competitive enzyme-linked immunosorben...
Tozon N, Kramaric P, Kos Kadunc V, Sersa G, Cemazar M.The aim of our study was to evaluate the efficacy of electrochemotherapy (ECT) with cisplatin as a single or adjuvant treatment for sarcoids in equids. Different treatment options with different success rates were proposed. Thirty-one horses and one donkey with different clinical type, size and location of tumours were treated with ECT as a single treatment (18 animals with 52 tumour nodules) or as adjuvant treatment with marginal surgical excision (14 animals with 18 tumour nodules). In animals treated only with ECT with cisplatin, complete response was obtained in 48/52 (92.3 per cent) nodul...
Dubey JP, Bauer C.There is considerable confusion concerning validity of Eimeria species in equids, and endogenous developmental stages and pathogenicity of equid Eimeria. This paper summarizes worldwide information on history, structure, life cycle, pathogenicity, prevalence, epidemiology, and diagnosis of Eimeria infections in equids. The following conclusions were drawn. Although three species of Eimeria; E. solipedum, E. uninugulata, and E. leuckarti were named from horses, only E. leuckarti is a valid species infecting equids, including horses, donkeys and zebra. We consider E. solipedum, E. uninugulata an...
Wutke S, Benecke N, Sandoval-Castellanos E, Döhle HJ, Friederich S, Gonzalez J, Hallsson JH, Hofreiter M, Lõugas L, Magnell O, Morales-Muniz A....Horses have been valued for their diversity of coat colour since prehistoric times; this is especially the case since their domestication in the Caspian steppe in ~3,500 BC. Although we can assume that human preferences were not constant, we have only anecdotal information about how domestic horses were influenced by humans. Our results from genotype analyses show a significant increase in spotted coats in early domestic horses (Copper Age to Iron Age). In contrast, medieval horses carried significantly fewer alleles for these phenotypes, whereas solid phenotypes (i.e., chestnut) became domina...
Bell SA, Pusterla N, Balasuriya UB, Mapes SM, Nyberg NL, MacLachlan NJ.Equids are commonly infected by herpesviruses, but isolation of herpesviruses from mules has apparently not been previously reported. Furthermore, the genomic relationships among the various equid herpesviruses are poorly characterized. We describe the isolation and preliminary characterization of a mule gammaherpesvirus tentatively identified as asinine herpesvirus-2 (AHV-2; also designated equid herpesvirus-7 (EHV-7)) from the nasal secretions (NS) of a healthy mule in northern California. The virus was initially identified by transmission electron microscopic examination of lysates of cell ...
Raudsepp T, Christensen K, Chowdhar BP.With the expansion of comparative genome analysis across different mammals, there is an increasing need to have well-defined banded karyotypes for the species chosen for investigation. In this context, the steadily growing gene mapping data in the donkey urgently require a framework whereby alignment/comparison of genetic information can be readily made with equids and other mammalian species. Hence a GTG-banded karyotype of the donkey (Equus asinus; EAS) is presented, along with schematic drawings and nomenclature of the banded chromosomes. In addition, the most characteristic features of ind...
Issel CJ, Foil LD.There is no credible evidence that the lentivirus that causes equine infectious anaemia (EIA) replicates in invertebrates. The virus persistently infects its equid hosts and is often present in blood in significant quantities. Blood-feeding arthropods thus have the potential to transfer the virus between hosts, especially if their feeding on the first host is interrupted and immediately continued on a second host. The general details and dynamics of mechanical transmission are included in this paper, as this agent presents an excellent model. Mechanical transmission can be effectively controll...
Myka JL, Lear TL, Houck ML, Ryder OA, Bailey E.Przewalski's wild horse (E. przewalskii, EPR) has a diploid chromosome number of 2n = 66 while the domestic horse (E. caballus, ECA) has a diploid chromosome number of 2n = 64. Discussions about their phylogenetic relationship and taxonomic classification have hinged on comparisons of their skeletal morphology, protein and mitochondrial DNA similarities, their ability to produce fertile hybrid offspring, and on comparison of their chromosome morphology and banding patterns. Previous studies of GTG-banded karyotypes suggested that the chromosomes of both equids were homologous and the differenc...
Nergadze SG, Belloni E, Piras FM, Khoriauli L, Mazzagatti A, Vella F, Bensi M, Vitelli V, Giulotto E, Raimondi E.Centromeres are the sites of kinetochore assembly and spindle fiber attachment and consist of protein-DNA complexes in which the DNA component is typically characterized by the presence of extended arrays of tandem repeats called satellite DNA. Here, we describe the isolation and characterization of a 137-bp-long new satellite DNA sequence from the horse genome (EC137), which is also present, even if less abundant, in the domestic donkey, the Grevy's zebra and the Burchelli's zebra. We investigated the chromosomal distribution of the EC137 sequence in these 4 species. Moreover, we analyzed its...
Futas J, Horin P.Natural killer (NK) cells have important functions in immunity. NK recognition in mammals can be mediated through killer cell immunoglobulin-like receptors (KIR) and/or killer cell lectin-like Ly49 receptors. Genes encoding highly variable NK cell receptors (NKR) represent rapidly evolving genomic regions. No single conservative model of NKR genes was observed in mammals. Single-copy low polymorphic NKR genes present in one mammalian species may expand into highly polymorphic multigene families in other species. In contrast to other non-rodent mammals, multiple Ly49-like genes appear to exist ...
Scorpio DG, Leutenegger C, Berger J, Barat N, Madigan JE, Dumler JS.Anaplasma phagocytophilum causes human granulocytic anaplasmosis by inducing immunopathologic responses. Its immunodominant Msp2 protein is encoded by a family of >100 paralogs. Msp2 (msp2) expression modulates in the absence of immune pressure, and prolonged in vitro passage modulates in vivo virulence. Because programmed MSP2 expression occurs in Anaplasma marginale, we hypothesized a similar event in A. phagocytophilum in vivo, with specific Msp2 expression triggering immunopathologic injury or clinical manifestations of disease. We examined msp2 transcripts in 11 B6 mice and 6 horses inocu...
McHorse BK, Biewener AA, Pierce SE.Digit reduction is a major trend that characterizes horse evolution, but its causes and consequences have rarely been quantitatively tested. Using beam analysis on fossilized centre metapodials, we tested how locomotor bone stresses changed with digit reduction and increasing body size across the horse lineage. Internal bone geometry was captured from 13 fossil horse genera that covered the breadth of the equid phylogeny and the spectrum of digit reduction and body sizes, from to To account for the load-bearing role of side digits, a novel, continuous measure of digit reduction was also esta...
Timoney JF.The etiology, epizootiology, pathogenesis, and clinical presentation of strangles are described. Streptococcus equi, the causative organism, is highly host-adapted to Equidae and shows no antigenic variation. Protective immunity apparently is mediated by a combination of serum opsonic and nasopharyngeal mucosal humoral responses. Vaccines based on M protein or inactivated bacterial suspensions may reduce the clinical attack rate by 50%, a level of protection much lower than that produced during recovery from strangles.
Norris SL, Kubasiewicz LM, Watson TL, Little HA, Yadav AK, Thapa S, Raw Z, Burden FA.Equids fulfil many different roles within communities. In low- to middle-income countries (LMICs), in addition to providing a source of income, equids also provide essential transport of food, water, and goods to resource-limited and/or isolated communities that might otherwise lack access. The aim of this investigation was to understand the welfare conditions that donkeys, mules, and horses are exposed to whilst working in Nepalese brick kilns. To understand the welfare conditions of equids in Nepalese brick kilns, the Welfare Aggregation and Guidance (WAG) tool in conjunction with the Equid ...
Marx JO, Olsson MC, Larsson L.To fully understand the effect of scaling on skeletal muscle shortening velocity (V (0)), it is important to know which phenotypic characteristics drive the changes between species. The purpose of the current investigation was to compare the effects of body mass and femur length, as an estimate of total limb length, on V (0) in species that cover a 100,000-fold range of body masses. Using the slack test procedure, V (0) was determined for fibers expressing types I and IIa myosin heavy chain (MyHC) isoforms in the mouse, rat, dog, human, horse, and rhinoceros under identical experimental condit...
Hanot P, Herrel A, Guintard C, Cornette R.Organisms are organized into suites of anatomical structures that typically covary when developmentally or functionally related, and this morphological integration plays a determinant role in evolutionary processes. Artificial selection on domestic species causes strong morphological changes over short time spans, frequently resulting in a wide and exaggerated phenotypic diversity. This raises the question of whether integration constrains the morphological diversification of domestic species and how natural and artificial selection may impact integration patterns. Here, we study the morpholog...
Timoney PJ.In an era of increasing globalization, the risk of spread of infectious diseases in humans and animals, including equids, has never been greater. International movement of equids and trade in semen are the most important factors responsible for the dissemination of various equine pathogens. Other factors that can or do have the potential to influence the global distribution of equine infectious diseases include: multinational trade agreements, emergent diseases, mutation of pathogens, climate related phenomena, migration of amplifying/reservoir hosts or vectors, availability of new vectors, va...
Schmitt D, Cartmill M, Griffin TM, Hanna JB, Lemelin P.At speeds between the walk and the gallop, most mammals trot. Primates almost never trot, and it has been claimed that they transition directly from a walk to a gallop without any distinctive mid-speed running gait. If true, this would be another characteristic difference between the locomotion of primates and that of most other quadrupedal mammals. Presently, however, few data exist concerning the actual presence or absence of intermediate-speed gaits (i.e. gaits that are used between a walk and a gallop) in primates. Video records of running in twelve primate species reveal that, unlike most...
Alves Ada S, Melo AL, Amorim MV, Borges AM, Gaíva E Silva L, Martins TF, Labruna MB, Aguiar DM, Pacheco RC.The aim of the study was to evaluate exposure of equids to rickettsial agents (Rickettsia rickettsii, Rickettsia parkeri, 'Candidatus Rickettsia amblyommii', Rickettsia rhipicephali, and Rickettsia bellii) and rickettsial infection in ticks of a Pantanal region of Brazil. Sera of 547 equids (500 horses and 47 donkeys) were evaluated by indirect immunofluorescence assay. In total, 665 adults and 106 nymphal pools of Amblyomma cajennense F. sensu lato, 10 Dermacentor nitens Neumann ticks, and 88 larval pools of Amblyomma sp. were tested by polymerase chain reaction (PCR). Overall, 337 (61.6%) eq...
Elschner MC, Melzer F, Singha H, Muhammad S, Gardner I, Neubauer H.Glanders, caused by Burkholderia (B.) mallei is a notifiable zoonotic disease in equidae. For international trade and movement of equids, certificates of negative serological test results for antibodies against B. mallei are required. To date, the complement fixation test (CFT) is the mandatory test to issue these health certificates. The CFT is difficult to standardize and, due to its poor specificity, often leads to false-positive reactions resulting in trade restrictions with considerable financial consequences. In the present study, the new ID Screen Glanders Double Antigen Multispecies EL...
Seeber PA, Quintard B, Sicks F, Dehnhard M, Greenwood AD, Franz M.Equine Herpesviruses (EHV) are common and often latent pathogens of equids which can cause fatalities when transmitted to non-equids. Stress and elevated glucocorticoids have been associated with EHV reactivation in domestic horses, but little is known about the correlation between stress and viral reactivation in wild equids. We investigated the effect of an environmental stressor (social group restructuring following a translocation event) on EHV reactivation in captive Grévy's zebras (). A mare was translocated by road transport from Zoo Mulhouse, France, to join a resident group of three ...
Galindo F, de Aluja A, Cagigas R, Huerta LA, Tadich TA.Equids are still used for diverse chores in Mexico and are essential for the livelihoods of numerous families. Appropriate health and behavior are prerequisites for performing work without affecting welfare. This study aimed to assess the welfare of working equids in Tuliman, applying the hands-on donkey tool. This tool evaluates five dimensions (behavior, body condition score [BCS], wounds, lameness, and other health issues) and was applied to 438 working equids (horses, mules, and donkeys). The Kruskall-Wallis test was applied to investigate differences between species and sex. Donkeys were ...
Hussain A, Jamil T, Tareen AM, Melzer F, Hussain MH, Khan I, Saqib M, Zohaib A, Hussain R, Ahmad W, Iqbal M, Neubauer H.Brucellosis is an important zoonosis worldwide. Equines are susceptible to the infection when in close contact with infected animals. The objective of our study was to update the existing knowledge and detect and differentiate the causative agent of brucellosis in breeding equines in Punjab, Pakistan. A cross-sectional study was designed to evaluate the occurrence and etiology of the infection in the equine population in three districts. A total of 448 equine sera were collected from three prefectures viz. Sahiwal, Khanewal, and Okara of the Punjab Province of Pakistan. Ninety-six (21.4%) samp...
Adelson DL, Raison JM, Garber M, Edgar RC.The interspersed repeat content of mammalian genomes has been best characterized in human, mouse and cow. In this study, we carried out de novo identification of repeated elements in the equine genome and identified previously unknown elements present at low copy number. The equine genome contains typical eutherian mammal repeats, but also has a significant number of hybrid repeats in addition to clade-specific Long Interspersed Nuclear Elements (LINE). Equus caballus clade specific LINE 1 (L1) repeats can be classified into approximately five subfamilies, three of which have undergone signifi...
Brinkmeyer-Langford C, Raudsepp T, Lee EJ, Goh G, Schäffer AA, Agarwala R, Wagner ML, Tozaki T, Skow LC, Womack JE, Mickelson JR, Chowdhary BP.A high-resolution (1 marker/700 kb) physically ordered radiation hybrid (RH) and comparative map of 122 loci on equine homologs of human Chromosome 19 (HSA19) shows a variant evolution of these segments in equids/Perissodactyls compared with other mammals. The segments include parts of both the long and the short arm of horse Chromosome 7 (ECA7), the proximal part of ECA21, and the entire short arm of ECA10. The map includes 93 new markers, of which 89 (64 gene-specific and 25 microsatellite) were genotyped on a 5000-rad horse x hamster RH panel, and 4 were mapped exclusively by FISH. The orie...
Suchan T, Kusliy MA, Khan N, Chauvey L, Tonasso-Calvière L, Schiavinato S, Southon J, Keller M, Kitagawa K, Krause J, Bessudnov AN, Bessudnov AA....DNA hybridization-capture techniques allow researchers to focus their sequencing efforts on preselected genomic regions. This feature is especially useful when analysing ancient DNA (aDNA) extracts, which are often dominated by exogenous environmental sources. Here, we assessed, for the first time, the performance of hyRAD as an inexpensive and design-free alternative to commercial capture protocols to obtain authentic aDNA data from osseous remains. HyRAD relies on double enzymatic restriction of fresh DNA extracts to produce RNA probes that cover only a fraction of the genome and can serve a...
Baker T, Carpenter S, Gubbins S, Newton R, Lo Iacono G, Wood J, Harrup LE.Biting midges of the genus Culicoides Latreille, 1809 (Diptera: Ceratopogonidae) cause a significant biting nuisance to equines and are responsible for the biological transmission of African horse sickness virus (AHSV). While currently restricted in distribution to sub-Saharan Africa, AHSV has a history of emergence into southern Europe and causes one of the most lethal diseases of horses and other species of Equidae. In the event of an outbreak of AHSV, the use of insecticide treated nets (ITNs) to screen equine accomodation is recommended by competent authorities including the Office Interna...
Grewar JD, Kotze JL, Parker BJ, van Helden LS, Weyer CT.South Africa is endemic for African horse sickness (AHS), an important health and trade-sensitive disease of equids. The country is zoned with movement control measures facilitating an AHS-free controlled area in the south-west. Our objective was to quantitatively establish the risk of entry of AHS virus into the AHS controlled area through the legal movement of horses. Outcomes were subcategorised to evaluate movement pathway, temporal, and spatial differences in risk. A 'no-control' scenario allowed for evaluation of the impact of control measures. Using 2019 movement and AHS case data, and ...