Topic:Equids
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.
Osteochondritis Dissecans (OCD)-Derived Chondrocytes Display Increased Senescence, Oxidative Stress, Chaperone-Mediated Autophagy and, in Co-Culture with Adipose-Derived Stem Cells (ASCs), Enhanced Expression of MMP-13. Osteochondritis dissecans (OCD) in equids, especially in sport horses, has become a growing issue as it contributes to the occurrence of lameness. Thus the aim of this study was to investigate the cytophysiological properties of OCD chondrocytes including expression of chondrogenic genes, apoptosis, mitochondria dynamics and autophagy. Horse chondrocytes were isolated from healthy (HE) and OCD cartilages. Properties of cells were evaluated using multiple assays e.g., polymerase chain reaction (PCR), immunofluorescence, Western blot. OCD chondrocytes were characterized by increased apoptosis an...
First Report of Acute Bilateral Hyphema in a Theileria equi-Infected Kathiawari Horse. Theileria equi is a tickborne hemoparasite that can cause severe illness in equids. In this report, we are describing a condition of acute bilateral hyphema in a 4-month-old Kathiawari filly infected with T. equi. The horse showed clinical signs such as fever, lethargy, icterus, tachycardia, tachypnea, and bilateral hyphema. Laboratory diagnosis revealed anemia and thrombocytopenia. Atypical clinical manifestation of bilateral hyphema, to our knowledge, has never been reported so far in equids infected with T. equi. The diagnosis was confirmed by microscopic examination of Geimsa-stained blo...
Utility of examining fallen stock data to monitor health-related events in equids: Application to an outbreak of West Nile Virus in France in 2015. Few studies about the use of quantitative equine mortality data for monitoring purposes are available. Our study evaluated the utility of monitoring emerging equine diseases using mortality data collected by rendering plants. We used approaches involving modelling of historical mortality fluctuations and detection algorithm methods to analyse changes in equine mortality in connection with the West Nile Virus (WNV) outbreak that occurred between July and September 2015 along the Mediterranean coast of France. Two weeks after the first equine WNV case was detected by clinical surveillance, detec...
High-resolution population structure and runs of homozygosity reveal the genetic architecture of complex traits in the Lipizzan horse. The sample ascertainment bias due to complex population structures remains a major challenge in genome-wide investigations of complex traits. In this study we derived the high-resolution population structure and levels of autozygosity of 377 Lipizzan horses originating from five different European stud farms utilizing the SNP genotype information of the high density 700 k Affymetrix Axiom™ Equine genotyping array. Scanning the genome for overlapping runs of homozygosity (ROH) shared by more than 50% of horses, we identified homozygous regions (ROH islands) in order to investigate the gene ...
Different effects of alpine woody plant expansion on domestic and wild ungulates. Changes in land-use and climate affect the distribution and diversity of plant and animal species at different spatiotemporal scales. The extent to which species-specific phenotypic plasticity and biotic interactions mediate organismal adaptation to changing environments, however, remains poorly understood. Woody plant expansion is threatening the extent of alpine grasslands worldwide, and evaluating and predicting its effects on herbivores is of crucial importance. Here, we explore the impact of shrubification on the feeding efficiency of Pyrenean chamois (Rupicapra p. pyrenaica), as well as ...
Frequency and factors associated with Theileria equi, Babesia caballi and Trypanosoma evansi in equids from Bahia (Northeast Brazil). The aim of this study was to determine the frequency and factors associated to Babesia caballi, Theileria equi and Trypanosoma evansi in naturally infected equids from the northeast Brazil. Blood samples from 569 equids (528 horses, 8 mules, and 33 donkeys) were collected and tested for the presence of DNA of each of these protozoan parasites by PCR. Generalized linear models were used to evaluate risk factors associated with the infection. The frequency of T. equi infection was 83.5% (475/569) - 84.3% in horses, and 73.2% in donkeys and mules. The results of the final model indicated that age...
Test of four hypotheses to explain the function of overmarking in foals of four equid species. Overmarking occurs when one individual places its scent mark directly on top of the scent mark of another individual. Although it is almost ubiquitous among terrestrial mammals, we know little about the function of overmarking. In addition, almost all studies on mammalian overmarking behaviour dealt with adult individuals. Reports on this behaviour in juveniles are extremely rare, yet may elucidate the function of this behaviour. We tested four mutually non-exclusive hypotheses which might explain this behaviour in juveniles: (1) conceal the individual's scent identity, (2) announcement of ass...
Left paralumbar fossa approach combined with mesocolon fenestration for bilateral equine ovariectomy. To describe a standing left paralumbar fossa approach combined with mesocolon fenestration for bilateral equine ovariectomy. Methods: Prospective experimental clinical study. Methods: Four healthy client-owned mares and 1 client-owned Molly mule. Methods: Mares were restrained in standing stocks and sedated with an α -agonist continuous infusion to effect. The abdominal cavity was approached via a left paralumbar fossa approach, and the contralateral right ovary was accessed through an incision in the mesocolon. The location of the window was adjusted to allow triangulation, adequate visualiz...
Retrospective evaluation of clinical outcome after chemotherapy for lymphoma in 15 equids (1991-2017). Prognosis associated with lymphoma in horses is poorly characterized, and treatment is often palliative. Long-term outcome after chemotherapy for horses with lymphoma is not well documented. Objective: To report long-term outcome of horses with lymphoma treated with chemotherapy. Methods: Fifteen equids. Methods: Retrospective case series. Medical record search and call for cases on the ACVIM listserv for horses treated with chemotherapy for lymphoma. Results: Fifteen cases with adequate data were identified. Complete remission was achieved in 5 horses (33.3%), partial response was achieved in...
Outcome following computed tomographic imaging and subsequent surgical removal of keratomas in equids: 32 cases (2005-2016). OBJECTIVE To describe the use of CT in the diagnosis of and presurgical planning for equids with keratomas treated by hoof wall resection and determine postoperative complications and outcome. DESIGN Retrospective case series. ANIMALS 29 horses and 3 mules with keratomas treated by partial or complete hoof wall resection following CT imaging of the distal portion of the affected extremity from 2005 through 2016. PROCEDURES For each equid, physical examination and lameness evaluation were performed, followed by imaging of the distal portion of the affected extremity. A tentative diagnosis of ke...
Genetic Diversity of Persian Arabian Horses and Their Relationship to Other Native Iranian Horse Breeds. The principal aims of this study were to explore genetic diversity and genome-wide selection signatures in Persian Arabian horses and to determine genetic relationship of Persian Arabians with other Iranian horse breeds. We evaluated 71 horses from 8 matrilineal strains tracing to 47 mares from the mid to late 19th century, using the equine 670k single nucleotide polymorphism (SNP) BeadChip. Mean observed and expected heterozygosity were (0.43) and (0.45), respectively, average inbreeding measures (inbreeding estimates based on runs of homozygosity and pedigree information) were low, indicatin...
Evolution and diversity of the EMA families of the divergent equid parasites, Theileria equi and T. haneyi. The equine parasite Theilera equi continues to curtail global equine commerce due primarily to its ability to persist indefinitely in the immunocompetent horse. Details regarding the parasite life cycle, pathogenesis and mechanism of persistence remain unclear. The recently discovered T. haneyi is also capable of persistence in the horse, creating a potential reservoir for additional infections. These two divergent parasites share a unique gene family that expresses surface merozoite antigens, or equi merozoite antigens (EMAs). The EMA family was maintained in number and size in both parasites...
Growth factor modulation of equine trophoblast mitosis and prostaglandin gene expression. To provide insight into maternal recognition of pregnancy control in equids, the mitogenic and developmental effects of endometrium-expressed growth factors (epidermal growth factor (EGF), fibroblast growth factor 2 (FGF2), hepatocyte growth factor (HGF), and insulin-like growth factor-1 (IGF-1)) were examined in equine iTr cells, an equine trophectoderm cell line. Initial western blots revealed that HGF and IGF-1 stimulate phosphorylation of AKT serine/threonine kinase 1 (AKT1) and EGF, FGF2, or HGF resulted in phosphorylation of both extracellular signal-regulated kinase 1 (ERK1) and ERK2...
Influence of dietary restriction and low-intensity exercise on weight loss and insulin sensitivity in obese equids. The importance of including exercise with dietary modification for the management of obese equids is not clearly understood. Objective: To evaluate the effect of a practical low-intensity exercise regimen, in addition to dietary restriction, on indices of insulin sensitivity (SI) and plasma adipokine concentrations in obese equids. Methods: Twenty-four obese (body condition score [BCS] ≥ 7/9) horses and ponies. Methods: Over a 12-week period, animals received either dietary restriction only (DIET) or dietary restriction plus low-intensity exercise (DIET+EX). All animals were provided wit...
Sequence and functional variability of Toll-like receptor 9 gene in equines. Significant structural differences in the extracellular domain of toll-like receptor 9 (TLR9) account for species-specific recognition of its ligand CpG-ODN sequences. TLR9 is extensively studied in human, mice and some domestic animals. The recognition ability appears to be utilized differently by various species and breeds, but so far no comprehensive study exists about the equine TLR9 gene. We characterized TLR9 sequences of Marwari and Zanskari breeds of horses and Poitu donkey. We sequenced and identified the protein coding regions of equine TLR9 and compared with other animals and human ...
Distribution, Diversity, and Evolution of Endogenous Retroviruses in Perissodactyl Genomes. The evolution of mammalian genomes has been shaped by interactions with endogenous retroviruses (ERVs). In this study, we investigated the distribution and diversity of ERVs in the mammalian order , with a view to understanding their impact on the evolution of modern equids (family ). We characterize the major ERV lineages in the horse genome in terms of their genomic distribution, ancestral genome organization, and time of activity. Our results show that subsequent to their ancestral divergence from rhinoceroses and tapirs, equids acquired four novel ERV lineages. We show that two of these ER...
West Nile virus associated with equid encephalitis in Brazil, 2018. Mosquito-borne arboviruses are a major public health concern worldwide and are responsible for emerging and re-emerging diseases. Taken together, the arboviruses have a strong impact on public health and are the most common causes of equine encephalitis. In-depth diagnostic investigation of equine viral encephalitis is of utmost importance for the epidemiological surveillance and control of this disease. Regarding neurological disorders in equids, in April-May 2018, at least 12 cases of equid mortality with acute neurological signs were reported in six farms from Espirito Santo state, Brazil. ...
Complications associated with closed castration using the Henderson equine castration instrument in 300 standing equids. To describe a closed castration technique in standing equids, report associated complications, and identify potential risk factors. Methods: Prospective cohort study of 300 standing equids that were castrated with the Henderson Equine Castrating Instrument. Methods: Thirteen participating veterinarians recorded intraoperative difficulties and postoperative complications. Descriptive statistics, univariate analyses with Fisher's exact tests, and logistic regressions were used to evaluate intraoperative difficulties and postoperative complications and to assess risk factors for postoperative com...
Cross-sectional study on gastro-intestinal parasites of equids in South-western Ethiopia. A cross sectional study was conducted in Jimma town from October 2010 to March 2011 with the objective of determining the status of intestinal nematode parasites of equids, and the association of different variables with infection rate. To address this, a total of 400 equids; donkeys (n = 29), horses (n = 317) and mules (n = 54) were used in this study and based on the coprological examination to identify parasite eggs, three species of nematodes were identified with an overall prevalence of 72.25%. A prevalence of 63.25%, 16.50%, 4.25%, and 10.75% were identified for Strongyles, ,...
Generation of an equine biobank to be used for Functional Annotation of Animal Genomes project. The Functional Annotation of Animal Genomes (FAANG) project aims to identify genomic regulatory elements in both sexes across multiple stages of development in domesticated animals. This study represents the first stage of the FAANG project for the horse, Equus caballus. A biobank of 80 tissue samples, two cell lines and six body fluids was created from two adult Thoroughbred mares. Ante-mortem assessments included full physical examinations, lameness, ophthalmologic and neurologic evaluations. Complete blood counts and serum biochemistries were also performed. At necropsy, in addition to tiss...
Prevalence of antibodies against Toxoplasma gondii and Neospora spp. in equids of Western Pará, Brazil. The present study aimed to determine the prevalence of antibodies against Toxoplasma gondii and Neospora spp. in equids raised for distinct purposes in the western state of Pará, Brazil, and to identify potential risk factors associated with parasite infection. A cross-sectional study was conducted with cluster sampling in 101 farms from 18 municipalities (farm horses). In visited municipalities, samples from sport and cart horses were included. Serum was obtained for detecting antibodies against T. gondii and Neospora spp. using indirect fluorescent antibody test, with a cut-off point of 1:6...
Molecular and morphological characterization of third instar Palaearctic horse stomach bot fly larvae (Oestridae: Gasterophilinae, Gasterophilus). Species of Gasterophilus are obligate parasites of equids and may induce severe, even lethal myiasis. However, identification of the third instar Gasterophilus larva at the species level is still problematic predominantly due to a shortage of diagnostic morphological features and incomplete molecular libraries. Testing the suitability of three different molecular markers showed that the traditional 650 bp barcode region near the 5' terminus of the cytochrome c oxidase subunit I (COI) served as a better tool for species-level identification than a 663 bp region near the 3' terminus of COI and a...
Survey for Equine Herpesviruses in Polar Bears (Ursus maritimus) and Exotic Equids Housed in US AZA Institutions. Infection by equine herpesvirus (EHV) strains (EHV-1, EHV-9) in ursid species, including polar bears ( Ursus maritimus), has been associated with neurological disease and death. A serosurvey of captive exotic equid and polar bear populations in US Association of Zoos and Aquaria institutions was performed to determine the prevalence of EHV strains using quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) tests. Equid species surveyed included zebra ( Equus spp.), Przewalski's wild horse ( Equus ferus przewalskii), Persian onager ( Equus hemionus), and So...
Minimally invasive, compartmentalized, modified open castration technique with primary closure in equids. OBJECTIVE To describe use of a modified open castration technique with a scrotal approach and primary closure in equids. DESIGN Prospective case series. ANIMALS 38 client-owned, sexually intact male equids. PROCEDURES With owner consent, elective castration was performed with a modified open technique on patients (1 pony, 1 miniature horse, and 36 horses of other breeds) under general anesthesia. The procedure included minimal dissection into the scrotal region for removal of testes, with cremaster muscles left intact and the parietal vaginal tunic closed in place. Primary closure of surgical ...
Genetic diversity and prevalence of piroplasm species in equids from Turkey. Equine piroplasmosis (EP) is a protozoon disease caused by Babesia caballi and Theileria equi transmitted by ticks from the Ixodidae family. This study investigated the genetic heterogeneity and diversity of piroplasm genotypes using the Reverse Line Blotting (RLB) technique for piroplasm species in equids in Turkey. A total of 233 blood samples from 142 horses and 91 donkeys were collected in Şanlıurfa, Tunceli, and Iğdır. The RLB assay was performed for simultaneous detection of piroplasm species. The prevalence of piroplasm infection was 33.5% (95% CI; 27.4-39.9). T. equi was the most c...
Social Learning in Horses-Fact or Fiction? Prima facie, the acquisition of novel behaviors in animals through observation of conspecifics seems straightforward. There are, however, various mechanisms through which the behavior of animals can be altered from observing others. These mechanisms range from simple hard-wired contagious processes to genuine learning by observation, which differ fundamentally in cognitive complexity. They range from social facilitation and local enhancement to true social learning. The different learning mechanisms are the subject of this review, largely because research on learning by observation can be conf...
Comparative seroprevalence and risk factor analysis of Trypanosoma evansi infection in equines from different agro-climatic zones of Punjab (India). As parasitaemia is low and fluctuating during the chronic stage of infection, accurate detection of Trypanosoma evansi in blood is difficult. The primary aims of this investigation were to assess for the first time the seroprevalence of T. evansi in all agro-climatic zones of Punjab, by indirect enzyme-linked immunosorbent assay (iELISA) and card agglutination test (CATT/T. evansi), and to evaluate the risk factors associated with latent trypanosomosis. A total of 319 equine serum samples collected from 12 districts of Punjab (India) belonging to different agro-climatic zones revealed 39 (12.2...
Molecular survey and genetic diversity of piroplasmids in equids from Midwestern Brazil. We evaluated the distribution of piroplasmids in equids from the Mato Grosso state in Midwestern Brazil using molecular methods and the interspecific genetic diversity. For this, 1,624 blood samples of equids from 973 farms were examined by PCR, using primer pairs that amplify a fragment of the genes rap-1 and ema-1 of Babesia caballi and Theileria equi, respectively. For molecular characterization and phylogenetic studies, 13 and 60 sequences of the rap-1 and ema-1 genes, respectively, were used to build a dendogram using maximum parsimony. B. caballi and T. equi were detected in 4.11% and 28...
Environmental stressors may cause equine herpesvirus reactivation in captive Grévy’s zebras (Equus grevyi). 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 ...