Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Species Comparison
Species comparison in horses involves examining the physiological, anatomical, and behavioral differences and similarities between horses and other animal species. This area of study can provide insights into the evolutionary adaptations and ecological roles of horses. Researchers often focus on aspects such as digestive systems, locomotion, sensory capabilities, and social structures to understand how horses have evolved to meet their environmental and survival needs. Comparative studies may also explore genetic differences and similarities, contributing to a broader understanding of species evolution and adaptation. This page aggregates peer-reviewed research and scholarly articles that analyze various aspects of species comparison involving horses, highlighting significant findings and methodologies used in the field.
Endocrine and uterine hemodynamic differences between intra- and interspecific equine pregnancies during early gestation. Interspecific equine pregnancies (mare x donkey) are associated with altered endocrine patterns and increased pregnancy loss; however, the relationship between hormonal dynamics, luteal activity, and uterine hemodynamics in relation to conceptus origin remains incompletely understood. This study aimed to evaluate the influence of conceptus origin on endocrine profiles, supplementary corpora lutea (SCL) formation, and uterine hemodynamics, and to investigate the relationships among these variables. Twenty mares were initially included; however, six were excluded due to pregnancy loss or incompl...
Comparative analysis of the karyotypes of Equus caballus and Equus asinus in the context of contemporary genomic data. Karyotypes of species within the genus Equus display considerable variation in chromosome number and are characterised by numerous structural rearrangements that have played a pivotal role in their evolutionary divergence and speciation. Equus caballus (horse), 2n = 64 and Equus asinus (donkey), 2n = 62, constitute particularly interesting models for comparative studies due to the diversified morphology of their chromosomes, including acrocentric and submetacentric pairs, documented Robertsonian translocations, and centric fusions. In recent decades, widely applied molecular cytogenetic techni...
Species-specific effects of spinal stiffness on gait and actuation-cost proxy in simulated cheetah and horse galloping. Cursorial quadrupeds employ distinct mechanical strategies for high-speed locomotion, with felids relying more strongly on axial motion than equids. The biomechanical role of spinal stiffness, however, is difficult to isolate experimentally because it is coupled to limb mechanics, morphology, and coordination. Here, we used comparative three-dimensional trajectory optimization to test how spinal stiffness influences gait mechanics and actuation-demand proxies in simulated cheetah-like and horse-like galloping. Homologous cheetah and horse models were evaluated across spinal-stiffness values, p...
Assessment of Thyroid Hormones Using the Immulite 2000xpi Analyzer in Healthy Donkeys. The Immulite 2000xpi, a chemiluminescent immunoassay (CLIA)-based analyzer, is currently recommended for measuring thyroid hormones (TH) concentrations in equids. However, scarce data are available on TH measurements in donkeys using this technique. Similarly, the effects of factors such as age and gender on TH concentrations have not been assessed with this analyzer. Serum free and total T4 and T3 concentrations were measured in 40 healthy donkeys (6.1 ± 0.8 years old; 8 intact jacks and 32 jennies) and 41 horses (10.7 ± 0.5 years old; 15 stallions and 26 geldings) using the Immulite 2000xp...
Reference interval for serum amyloid a in apparently healthy donkeys measured with a donkey-specific ELISA. Serum amyloid A (SAA) is a major acute phase protein used as an inflammatory biomarker in equine medicine. However, no universally accepted assay-specific reference interval (RI) exists for donkeys, and available literature remains limited, with only few studies using different donkey breeds and immunoassay platforms. This study aimed to establish an assay- and population-specific RI for serum SAA in apparently healthy donkeys using a species-specific double sandwich ELISA. Unassigned: Serum SAA concentrations were measured in 176 apparently healthy donkeys. RI estimation followed ASVCP/CLSI r...
Hair steroid hormones concentrations in jennies and their donkey foals from parturition to 6 months postpartum. The period after parturition/birth represents a delicate time for the dam and the offspring, during which several physiologic changes occur under finely tuned hormonal control, with the hypothalamic-pituitary- adrenal (HPA) axis playing a key role. This period, well studied in horses, received little attention in donkeys, despite the importance of species-specific knowledge for population preservation programs in many endangered donkey breeds. The present study aimed to investigate cortisol (C), DHEA(S), 17-β-estradiol (E2), progesterone (P4), testosterone (T), and allopregnanolone (AlloP) ha...
Morphological study of nasal diverticulum in Grant’s zebra (Equus quagga boehmi Matschie, 1892). The nasal diverticulum (ND), a blind cutaneous pouch extending from the nasal vestibule (NV), is unique to Equidae. Although anatomical and histological descriptions of the ND are available for horses and donkeys, detailed studies in zebras remain limited. Objective: To investigate and characterize the anatomical and histological features of the ND in zebras and compare these findings with those observed in other species. Methods: Silicone casts of the NDs were prepared from two of three female Grant's zebra carcasses for anatomical measurements, followed by dissection for gross morphological ...
Fecal microbiota of weaned equine and mule foals grazing bermudagrass pastures. Weaning is a critical period in the lives of foals. After weaning, forage consumption represents a major challenge for both equine or mule foals. Objective: This study evaluated the fecal bacterial concentration, composition, diversity and differential abundance in weaned equine and mule foals under rotational grazing on Bermudagrass (Cynodon spp.) pasture. Methods: A randomized design was used with equine and mule foals grazing two rotations on three Bermudagrass cultivars (Coastcross, Florakirk, and Tifton-85). Pasture rotation occurred every 20 days. The first rotation was evaluated at 20, ...
Ultrasonographic fetal sex determination in large domestic animals: a comparative, mechanistic, and field-oriented synthesis. Ultrasonographic fetal sex determination is commonly used in livestock production to aid genetic selection, reproductive planning, and economic optimization. Despite consistently high diagnostic accuracies under controlled conditions, its use in field settings is variable and frequently unpredictable. This disparity is due to the combined effects of embryological development, species-specific anatomy, fetal positioning, operator expertise, and technical limitations. Unassigned: This review aims to provide a comparative and integrative synthesis of ultrasonographic fetal sex determination acros...
Neuroimmune Mechanisms in Equine Asthma: Primary Inflammatory Triggers, Neuroimmune Modulation and Chronic Airway Remodelling. Equine asthma is a chronic inflammatory disease of the lower respiratory tract, primarily associated with inhalation of organic dust, microbial particles and environmental aeroantigens. Although the inflammatory and immunological mechanisms underlying equine asthma have been extensively investigated, the potential contribution of neuroimmune pathways remains poorly understood. In humans and rodent models, asthma is increasingly recognised as a disorder involving complex bidirectional interactions between the nervous and immune systems. Sensory nerve activation, neuropeptide release, autonomic ...
The “gait keeper” mutation does not influence gait scores in Pêga donkeys: a preliminary result. The DMRT3 "gait keeper" mutation is a major determinant of locomotor patterns in horses, but its role in donkeys remains unclear. This study evaluated the association between this polymorphism and gait performance in Pêga donkeys, a breed selected for gaited locomotion. A total of 260 animals were phenotyped for gait scores and genotyped by PCR-sequencing targeting exon 2 of DMRT3. All individuals were homozygous for the wild-type allele (CC), and the mutant A allele was not detected. The monomorphism precludes any association with gait scores, possibly indicating that this DMRT3 mutation has...
Extinct Dalian horse as a genetic bridge between Late Pleistocene North American and Eurasian equids. Pleistocene caballine horses exhibited considerable genetic diversity and maintained broad population connectivity across their range. The extinct Dalian horse (Equus dalianensis) from northeastern China likely contributed to this network. Here, we sequenced 20 complete mitochondrial and two nuclear genomes, establishing the Dalian horse as a distinct genetic clade within Northeast Eurasian caballines and extending its known geographic distribution. Ancestry component analyses revealed a distinctive component of Eastern Beringian (E-EBer), i.e. American ancestry in Dalian horses, absent from o...
Characterization of Capillary Zone Electrophoresis in Horses and Donkeys. There are no capillary zone electrophoresis (CZE) comparative studies between horses and donkeys. Our objectives were to compare CZE results between both species, establish reference intervals (Ris), study age- and sex-related changes, determine the prevalence of bisalbuminemia, and correlate spectrophotometric albumin results with those calculated based on two different CZE methods. We performed CZE in 50 healthy horses and 49 healthy donkeys. There were significant differences ( < 0.03) in every protein fraction percentage and concentration (except for the β-globulins percentage) between...
Open habitats and species differences shape space use in semi-feral cattle and horses across Danish rewilding sites. Large herbivores can strongly influence ecosystem structure and biodiversity, making knowledge of their space use important for trophic rewilding. We used GPS-tracking data collected over two years from 10 semi-feral cattle and 17 horses across ten Danish rewilding sites to analyse habitat use in a use-availability framework using resource selection functions (RSFs), complemented by direct behavioural observations. Both species showed large individual variability but overall used habitats disproportionately to availability, with higher relative use of open habitats; including dry grassland and...
Long-Read Sequencing for Species-Level Resolution of the Equine Gut Microbiota Reveals the Need for Improved Databases. Differences in gut microbiota composition related to diet have been reported in horses, but characterization of specific microbial taxa remains limited, particularly at the species level. The objective of this study was to use long-read sequencing of the 16S rRNA gene to provide additional taxonomic insight into the intestinal microbiota in horses. Fecal samples were collected from 12 horses on pasture and from 6 of them after switching to a hay diet. Sequencing yielded low read counts per sample, and the analysis failed to detect statistical differences in alpha- and beta-diversity among diet...
Telomere-to-telomere Genome Assembly of Equus kiang (Tibetan wild donkey). The Tibetan wild donkey (Equus kiang) is an endemic equid species inhabiting the Qinghai-Tibet Plateau, exhibiting remarkable chromosomal diversity within the Equus genus. Here we present a chromosome-level, telomere-to-telomere genome assembly for E. kiang generated using Illumina short reads, PacBio HiFi long reads, and Hi-C sequencing data. The final assembly spans 4.02 Gb and comprises 27 pseudochromosomes. Specifically, 8 chromosomes are gapless, 8 chromosomes have one gap, 7 chromosomes have 2-4 gaps, and the remaining 4 chromosomes have five or more gaps. Benchmarking Universal Single...
Is managing horses ‘as wild’ beneficial for dung beetle assemblages and their associated ecological functions? In Europe, where livestock has largely replaced wild ungulates over the centuries, dung beetle assemblages have become largely dependent on livestock farming. The radical changes in livestock farming practices during the 20th century have therefore had a profound impact on these assemblages. Trophic rewilding with large herbivores is an important focus in European rewilding projects, and dung beetle assemblages appear to be good indicators of the success of rewilding. By comparing the composition of dung beetle assemblages and the rate of dung disappearance in three neighboring grassland habit...
Prevotella mikamonis sp. nov., isolated from equine clinical specimens. In this study, five strains of anaerobic, Gram-negative, rod-shaped bacteria were characterized phenotypically, biochemically and genotypically. These strains were clinically isolated from horse specimens in Japan. Phylogenetic trees constructed based on 16S rRNA gene sequence comparisons showed distinct clustering of the five strains with the type strains of closely related species. The genomic DNA G+C content was 46.7 mol%. The major cellular fatty acids identified were C, 3-OH-C and 3-OH-iso-C. Whole-genome comparisons based on average nucleotide identity using blast (ANIb) and digital DNA...
Adrenocorticotropic Hormone and Thyroxine Concentrations in Young Healthy Equids: Species Differences and Seasonal Variations. Due to growing interest in endocrine diseases, more studies aim to interpret the baseline concentrations and reference intervals of hormone values like adrenocorticotropic hormone (ACTH) and thyroxine (T4) in horses. Most studies available in the literature focus on evaluating ACTH and thyroid hormone values in adult and geriatric horses, with only a few considering younger donkeys and ponies. This study aimed to measure ACTH and T4 in autumn and spring in younger equids. The study included 42 young equids, which were divided into three groups: horses, ponies, and donkeys. The concentration of...
Comparative analysis of uterine inflammation in jennies and mares after insemination with cryopreserved donkey semen. The limited fertility of jennies inseminated with frozen donkey semen remains a major challenge for donkey reproduction and conservation, contrasting with the more favorable outcomes observed in mares. Species-specific differences in post-breeding uterine inflammation have been proposed as a key factor underlying this disparity. This study compared the uterine inflammatory response and pregnancy outcomes of jennies and mares inseminated with frozen donkey semen. Twelve jennies and eleven mares were monitored over 48 and 44 estrous cycles, respectively. Artificial insemination (AI) was performe...
Monitoring trace minerals and heavy metals in liver of free-living large herbivores in the Netherlands. Trace minerals are essential for animal health but can also, together with heavy metals, have a negative impact, making their monitoring crucial to assess animal health. These elements were examined through a long-term post-mortem monitoring system based on routine liver sampling for Heck cattle, Konik horses and red deer in place at the Oostvaardersplassen nature reserve in the Netherlands, using data from this system to determine reference intervals and investigate trends in liver trace element concentrations. Throughout the monitoring programme, inductively coupled plasma mass spectrometry ...
Transthoracic impedance in adult Thoroughbred horses is similar to other species. To determine transthoracic impedance (TTI) in adult horses using an exponential biphasic defibrillator and investigate patient and technique factors influencing TTI. Unassigned: A randomized crossover design with 2 phases was used. Phase 1: TTI was measured in dorsal and lateral recumbency, with and without manual pressure on the electrodes in deceased horses immediately following euthanasia. Phase 2: TTI was measured in dorsal recumbency during inspiration and expiration using anesthetized live horses sourced from 2 terminal studies. Mixed-effects linear regression modeling was performed to a...
Space-use by feral cattle and horses shapes vegetation structure in a trophic rewilding area. Feral cattle (Bos taurus) and horses (Equus ferus caballus) are commonly introduced to European rewilding areas to halt vegetation succession and to conserve light-demanding species. Yet, we still do not understand how the habitat preference of animals shapes vegetation structure at the landscape scale. Here, we used spatial preference modeling to understand drivers of space-use based on GPS-collared horses and cattle in a 120-ha rewilding area in Denmark. Using a time series of a satellite-based vegetation productivity index, we tested the ability of animal space-use to explain changes in veg...
Translational human and equine regenerative medicine in musculoskeletal conditions. Translational regenerative medicine, integrating human and veterinary approaches within the "One Health" framework, increasingly uses horses as models for human musculoskeletal conditions due to shared anatomical and functional features. Osteoarthritis and tendon disorders affect both species, often resulting from high-impact or repetitive strain activities. Regenerative medicine offers therapeutic opportunities by promoting tissue repair and modulating inflammation. Cellular orthobiologics such as mesenchymal stromal/stem cells (MSCs) show promise for treating osteoarthritis and tendon injuri...
Evaluation of corneal sensitivity in 40 Pantaneiro horses using the Cochet-Bonnet esthesiometer. Corneal sensitivity is a crucial ophthalmic parameter for the protection and maintenance of ocular health in horses. Unassigned: This study aimed to evaluate the corneal sensitivity of 40 Pantaneiro horses using the Cochet-Bonnet esthesiometer, in order to establish reference values for this population. Unassigned: The animals were considered clinically healthy after a complete ophthalmic examination. Measurements were taken in both eyes, and the data were analyzed for mean, standard deviation, and potential differences between eyes, sex, and age groups. Unassigned: The average corneal sensiti...
Cross-Species Analysis of Transcriptomic Response to Alpha-Herpesvirus Infection in Human, Bovine and Equine Cells. Comparative transcriptomics offers a powerful approach to elucidate host-virus interactions across related pathogens, yet systematic evaluations across species-matched cellular systems remain limited. We performed a cross-species RNA sequencing analysis of respective species' cells infected with three alphaherpesviruses-herpes simplex virus 1 (HSV-1), bovine alphaherpesvirus 1 (BHV-1), and equid alphaherpesvirus 1 (EHV-1)-to dissect conserved and virus-specific transcriptional responses. We show that certain orthologous genes and orthologous pathways are differentially regulated upon infection...
Absence of Host-Specific Hemotropic Mycoplasmas in Horses and Donkeys from Croatia: First Systematic Survey in Southeastern Europe. Hemotropic mycoplasmas (hemoplasmas) are uncultivable, cell wall-less bacteria that parasitizeon the surface of red blood cells of mammals, potentially causing anemia and other systemic signs. While widely distributed among domestic and wild animals, their occurrence in equids remains poorly understood, and no species has been identified as host-specific to horses or donkeys. This study presents the first systematic survey of hemoplasmas in equids from southeastern Europe and only the second molecularly confirmed case in horses in Europe. A total of 843 equids (817 horses and 26 donkeys) from ...
The petrosal and bony labyrinth of extinct horses (Perissodactyla, Equidae) and their implications for perissodactyl evolution. Perissodactyla, or odd-toed ungulates, are represented today by 16 species of rhinoceroses, tapirs, and horses. Perissodactyls were much more diverse in the past, having a rich fossil record spanning from the earliest Eocene (~56 Ma) to recent, including a myriad of extinct lineages. Despite over a century of study, the inter-relationships of some extinct perissodactyl families remain poorly resolved. New morphological characters are needed to help solve this issue. Recent studies suggest that the ear region, ., the petrosal and the bony labyrinth of the inner ear, is a valuable source of morp...
Histomorphometric Analysis of the Endometrium of Jennies (Equus asinus) and Mares (Equus caballus) in Estrus: Anatomical Differences and Possible Reproductive Implications. Assisted reproductive techniques are often extrapolated from horses to donkeys, despite poorer fertility outcomes in jennies. This issue has been attributed to unknown uterine species-specific differences. This study compared, through histomorphometry, the endometrium of jennies and mares. Endometrial biopsies (N = 12) were taken from reproductively sound jennies (n = 6) and mares (n = 6) in estrus. Histomorphometric analysis evaluated luminal (LE, µm) and glandular epithelium height (GE, µm), glandular lumen diameter (LD, µm), glandular area (GA, µm), the number of glands (#G), and glandu...
Exosome and miRNA Content Engagement in the Physical Exercise Response: What Is Known to Date in Atheltic Horses? To date, there is extensive scientific evidence affirming that physical exercise plays a fundamental role in both the prevention and treatment of various pathological conditions in humans as well as in animals. It is understood that the advantages of movement and exercise have a multifactorial origin and they depend on a category of bioactive molecules vehicolated by extracellular microvesicles known as exosomes. The exosomes act as potential delivery systems for messages within the organism. These findings have drawn significant attention, leading researchers to further investigate the role o...
