Morphology in horses refers to the study of the form and structure of the equine body, including the skeletal, muscular, and integumentary systems. This field encompasses the examination of physical characteristics such as body conformation, limb structure, and cranial features, which can influence a horse's performance, health, and suitability for various activities or disciplines. Morphological assessments are often used in breeding programs to select for desirable traits and in veterinary evaluations to identify potential anatomical issues. This page aggregates peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and implications of morphological studies in equine science.
Giontella A, Sarti FM, Biggio GP, Giovannini S, Cherchi R, Pieramati C, Silvestrelli M.The purpose of this study was to estimate the heritability and genetic correlations of four biometric measurements and an overall score (OS) in the Sardinian Anglo-Arab horse (SAA); moreover, the effect of inbreeding on these traits was investigated. A dataset with 43,624 horses (27,052 females and 16,572 males) was provided by the Agricultural Research Agency of Sardinia (AGRIS). Cannon bone circumference (BC), chest girth (CG), shoulder length (SL), and withers height (WH) were measured on 6033 SAA horses born in Sardinia between 1967 and 2005; beside the measurements, an overall score (OS) ...
Apprich V, Licka T, Freiler S, Gabriel C.Impaired keratinocyte differentiation has recently been suggested as a key event in equine hoof canker development. Koilocytotic appearance of keratinocytes, one of the most characteristic morphological alterations in hoof canker tissue, is also a common marker for papillomavirus (PV) infection, and bovine PV-1 and/or -2 (BPV-1/2) has previously been detected in equine canker patients. Therefore, the present study aimed to correlate the frequency and severity of koilocytotic keratinocytes with BPV detection in hoof canker samples. Hoof tissue of 5/18 canker-affected horses and 2/6 control hors...
Nieth J, Krohn J.Aim of the study was to describe the echotexture and dimensions of the kidneys including the renal pelvis in neonatal foals using transabdominal sonography. Methods: In the course of a preliminary examination, sonographic examinations of the kidneys of 10 dead newborn foals were performed in order to determine their localization, measurement parameters, and echotexture. In subsequent necropsies, the kidneys were measured and the obtained values were compared with the sonographic measurements. A high level of agreement between the both measurement values could be demonstrated. In the main exami...
Salamanca-Carreño A, Jordana J, Crosby-Granados RA, Bentez-Molano J, Parés-Casanova PM.This is the first morphological comparative study between local horses and mules from Arauca, Colombia. It was realized to compare morphological traits between both species by analysing 15 adult mules (7 males and 8 females) and 150 adult horses (137 males and 13 females), with an age interval from 2 to 22 years. Data consisted of 24 different body quantitative traits which can explain the body conformation: thoracic circumference, body length (BL), thoracic depth and width, withers height (WH), sternum height, shoulders width, chest width, forelimb cannon perimeter and length, head length and...
Gee C, Small A, Shorter K, Brown WY.Equine Caudal Cervical Morphologic Variation (ECCMV) is a congenital malformation of the caudal cervical spine distinct from the more commonly recognized Cervical Vertebral Stenotic Myelopathy (CVSM). The most common presentation of ECCMV is recognized on the sixth cervical vertebra (C6). In "normal" presentations, the transverse processes on the left and right sides have a caudal lamina projecting ventrally below the caudal vertebral body in a heel shape. With ECCMV, variations occur to the structure of the caudal ventral lamina on one or both sides of C6 and may include the seventh cervical ...
Graves KT, Eberth JE, Bailey E.Homozygous and compound heterozygous Miniature horses for ACAN alleles D1, D2, D3* and D4 exhibit chondrodysplastic dwarfism (OMIA 001271-9796). In a previous study, the carrier rate for these four alleles, combined, was 26.2%. The purpose of this study was to investigate whether carriers of these dwarfism-causing alleles had a shorter withers height than non-carriers. A total of 245 Miniature horses were tested for these four ACAN alleles and also were measured for withers height. Of these horses, 98 were carriers and 147 were non-carriers. A statistically significant difference of 1.43 inche...
Kavanagh KD, Bailey CS, Sears KE.Previous work comparing the developmental mechanisms involved in digit reduction in horses with other mammals reported that horses have only a 'single digit', with two flanking metapodials identified as remnants of digit II and IV. Here we show that early embryos go through a stage with five digit condensations, and that the flanking splint metapodials result from fusions of the two anterior digits I and II and the two posterior digits IV and V, in a striking parallel between ontogeny and phylogeny. Given that even this most extreme case of digit reduction exhibits primary pentadactyly, we re...
Wuri L, Agca C, Agca Y.This study compared the morphometric, subcellular characteristics, in vitro fertilisation (IVF) and embryonic developmental potential of metaphase II (MII) mouse oocytes obtained from females superovulated with either anti-inhibin serum-human chorionic gonadotrophin (AIS-hCG) or pregnant mare serum gonadotrophin (PMSG)-hCG. The oocyte's quantity, quality, zona pellucida (ZP) thickness, perivitelline space (PVS), diameter, microtubules, F-actin, cortical granules (CGs) and mitochondrial distribution were determined. Superovulation using AIS-hCG resulted in a higher numbers of oocyte/donor compa...
Vershinina AO, Kapp JD, Baryshnikov GF, Shapiro B.Museum collections are essential for reconstructing and understanding past biodiversity. Many museum specimens are, however, challenging to identify. Museum samples may be incomplete, have an unusual morphology, or represent juvenile individuals, all of which complicate accurate identification. In some cases, inaccurate identification can lead to false biogeographic reconstructions with cascading impacts on paleontological and paleoecological research. Here, we analyzed an unusual Equid mandible found in the Far North of the Taymyr peninsula that was identified morphologically as Equus hemionu...
Parés-Casanova PM, Salamanca-Carreño A, Crosby-Granados RA, Bentez-Molano J.Skull size and shape have been widely used to study domestic animal populations and breeds. Although several techniques have been proposed to quantify cranial form, few attempts have been made to compare the results obtained by different techniques. While linear morphometrics has traditionally been used in breed characterization, recent advances in geometric morphometrics have created new techniques for specifically quantifying shape and size. The objective of this study was to compare two morphometric methods for their ability to describe external morphology. For this purpose, 20 skull specim...
Ma CL, Ye YL, Wen T, Huang ZM, Pan J, Hu JJ, Tao JP, Song JL.Three cyst-forming Sarcocystis species have been identified in horsemeat; however, there exists considerable confusion concerning their relationships. Here, 74% (34/46) of the examined tissue samples from horses contained sarcocysts based on examination by light microscopy (LM), and the organism was identified as Sarcocystis bertrami based on cyst structure. The S. bertrami cysts were microscopic (up to 6750 μm in length) and exhibited a striated wall with 2.0-5.1 μm villar protrusions (vps) under LM. Transmission electron microscopy (TEM) observations showed that the vps were tightly pack...
Cunha Dos Santos FC, Morrell JM, Nunes MM, Nogueira CE, Curcio BR, Malschitzky E.Epididymal sperm cryopreservation represents the ultimate option to preserve spermatozoa of valuable stallions. Objective: The study aims to evalute whether single layer centrifugation (SLC) prior to cryopreservation or after post-thawing improves the quality of stallion epididymal sperm. Methods: Epididymal sperms of stallions were harvested (N=20). Sperm samples were subjected to treatments: conventional centrifugation, SLC prior to cryopreservation (SLC-PC) or SLC post-thaw (SLC+). All samples were cryopreserved, thawed and evaluated. SLC+ were thawed, single layer cenrifuged and resuspende...
Jensen RB, Rockhold LL, Tauson AH.The main objectives of this study were to evaluate the accuracy of different body weight formulas for estimating body weight of Icelandic and Warmblood horses, as well as to assess the associations between the variables cresty neck score, body condition score, and plasma concentrations of leptin, insulin and cortisol. A total of 81 adult (≥ 4 years of age) horses (43 Icelandic and 38 Warmblood horses) was included in this study. The following morphological measurements were collected by two examiners simultaneously; body weight; height at withers; neck length; 0.5 neck length; neck circum...
Rossi M, Gonzalez-Castro R, Falomo ME.Different additives have been tested in cooled stallion sperm, in order to maintain sperm quality and to ameliorate the decrease in sperm fertility potential. In several species, caffeine and pentoxifylline promote sperm motility by increasing energy production. We evaluate the effects of caffeine and pentoxifylline when added to stallion sperm before or after cooling. Three ejaculates from five stallions each were processed and resuspended in skim milk extender. Caffeine (5 mM), pentoxifylline (3.5 mM), or both additives combined were included to sperm before or after cooling (4°C for 24 ...
Medeiros BR, Garbade P, Seixas L, Peripolli V, McManus C.The aim of this study was to evaluate genetic parameters for subjective scores given at the Brazilian Sport Horse (BSH) Stallion Approval by estimating heritability (h) for morphological, gait, and jumping traits and genetic correlations (γ) among the functional ones and by verifying selection feasibility. The analysis included 1179 complete evaluations from 294 horses, by 4.26 ± 0.96 judges. Each trait was evaluated using mixed models in SAS® v9.2, considering the individual as a random effect. Variance components and genetic parameters were obtained by single and two-trait animal mode...
Egbe-Nwiyi TN, Paul BT, Cornelius AC.This study aimed to investigate the prevalence and intensity of nematode infection among slaughtered donkeys in Kaltungo, Nigeria. Methods: A total of 72 fecal samples were examined by salt flotation and the modified McMaster fecal egg count technique to morphologically identify nematodes eggs and determine their egg per gram (EPG) outputs. Results: Out of a total of 72 (100%) donkeys sampled, 36 (50%) tested positive, but the prevalence of nematodes was independent of the age, sex, and breed of donkeys (p>0.05). Among the four species of nematodes identified in single and mixed infections,...
Ribitsch I, Gueltekin S, Keith MF, Minichmair K, Peham C, Jenner F, Egerbacher M.Aging is hypothesized to be associated with changes in tendon matrix composition which may lead to alteration of tendon material properties and hence propensity to injury. Altered gene expression may offer insights into disease pathophysiology and thus open new perspectives toward designing pathophysiology-driven therapeutics. Therefore, the current study aimed at identifying naturally occurring differences in tendon micro-morphology and gene expression of newborn, young and old horses. Age-related differences in the distribution pattern of tendon fibril thickness and in the expression of the ...
Domanska-Kruppa N, Venner M, Bienert-Zeit A.Class II malocclusion is the most frequently occurring congenital malocclusion in horses. Radiographic cephalometric procedures adopted from human dentistry were used to study the development of overjet in a population of 650 Warmblood foals. Thirteen foals were diagnosed with measurable overjet at the beginning of the study. The malocclusion in nine foals resolved spontaneously and four foals without overjet at 2 weeks of age developed the condition during the first year of life. A cephalostat used in human orthodontics to immobilize the patient's head while being radiographed was replaced by...
Ducheyne KD, Rizzo M, Cuervo-Arango J, Claes A, Daels PF, Stout TAE, de Ruijter-Villani M.Invitro embryo production is an increasingly popular means of breeding horses. However, success is limited by a high incidence of early embryo loss. Although there are various possible causes of pregnancy failure, chromosomal abnormalities, including aneuploidy, are important potential contributors. This study evaluated the frequency of micronucleus formation as a proxy for aneuploidy in invitro-produced (IVP) and invivo-derived horse blastocysts. Associations between IVP embryo morphology, frequency of nuclear abnormalities and the likelihood of pregnancy were investigated. IVP blastocysts ex...
Brooks KE, Daughtry BL, Metcalf E, Masterson K, Battaglia D, Gao L, Park B, Chavez SL.The timing of early mitotic events during preimplantation embryo development is important for subsequent embryogenesis in many mammalian species, including mouse and human, but, to date, no study has closely examined mitotic timing in equine embryos from oocytes obtained by ovum pick-up. Here, cumulus-oocyte complexes were collected by transvaginal follicular aspiration, matured invitro and fertilised via intracytoplasmic sperm injection. Each fertilised oocyte was cultured up to the blastocyst stage and monitored by time-lapse imaging for the measurement of cell cycle intervals and identifica...
Jinglong X, Xiaobin L, Fang Z, Chenchen W, Kailun Y.The aim of this research was to isolate bacteria capable of biotransforming daidzein from fresh feces from pregnant horses. A Hungate anaerobic roller tube was used for anaerobic culture. Single colonies were picked at random and incubated with daidzein. High performance liquid chromatography was used to detect whether the isolated bacteria were able to biotransform the substrate. A strain capable of reducing daidzein was selected and characterized using sequence analysis of 16S rDNA, and a phylogenetic tree was constructed. The morphological physiological and biochemical characteristics of th...
May-Davis S, Vermeulen Z, Hunter R, Brown W.For over 200 years, equine anatomic literature has chiefly portrayed the attachment points of the nuchal ligament lamellae (NLL) from the second to the seventh cervical vertebrae (C2-C7). However, recent studies have shown that the modern domestic horse, Equus caballus, primarily exhibits the attachments points from C2-C5. Here we present the rare finding of a complete NLL attached from C2-C7 in one Australian Stock Horse (ASH) and discuss the potential implications of these findings. Previously, this trait has only been confirmed among close descendants of Equus ferus ferus; namely the primi...
Carnevale EM, Metcalf ES.Intracytoplasmic sperm injection (ICSI) is used to produce equine embryos invitro. The speed of embryo development invitro is roughly equivalent to what has been described for embryos produced invivo. Morphological evaluations of ICSI-produced embryos are complicated by the presence of debris and the dark nature of equine embryo cytoplasm. Morulas and early blastocysts produced invitro appear similar to those produced invivo. However, with expansion of the blastocyst, distinct differences are observed compared with uterine embryos. In culture, embryos do not undergo full expansion and thinning...
Martino NA, Marzano G, Mastrorocco A, Lacalandra GM, Vincenti L, Hinrichs K, Dell Aquila ME.Time-lapse imaging was used to establish the morphokinetics of equine embryo development to the blastocyst stage after invitro oocyte maturation (IVM), intracytoplasmic sperm injection (ICSI) and embryo culture, in oocytes held overnight at room temperature (22-27°C; standard conditions) before IVM. Embryos that developed to the blastocyst stage underwent precleavage cytoplasmic extrusion and cleavage to the 2-, 3- and 4-cell stages significantly earlier than did embryos that arrested in development. We then determined the rate of blastocyst formation after ICSI in oocytes held for 2 days at ...
Lewis N, Schnauffer K, Hinrichs K, Morganti M, Troup S, Argo C.The use of time-lapse imaging (TLI) in the evaluation of morphokinetics associated with invitro developmental competence is well described for human, cattle and pig embryos. It is generally accepted that embryos that complete early cleavage sooner are more likely to form blastocysts and that timing of later events, such as blastocyst formation and expansion, are predictive of implantation potential and euploid status. In the horse, morphokinetics as a predictor of developmental competence has received little attention. In this study we evaluated the morphokinetics of early equine embryo develo...
Frank BL, Doddman CD, Stokes JE, Carnevale EM.In this retrospective study the morphological characteristics of oocytes and cleavage stage embryos were associated with pregnancy results from clinical intracytoplasmic sperm injection (ICSI) in mares. Oocytes were collected from preovulatory follicles, and images (×200; n=401) were captured for measurements of ooplasm, the perivitelline space and zona pellucida. After ICSI and before transfer into recipients' oviducts, cleavage stage embryos were imaged (n=178). Oocyte donor ages (3-13, 14-19, 20-23, 24-27 years) were compared, as were mares aged 3-13 years without versus with recent histor...
Hybridization has been widely practiced in plant and animal breeding as a means to enhance the quality and fitness of the organisms. In domestic equids, this hybrid vigor takes the form of improved physical and physiological characteristics, notably for strength or endurance. Because the offspring of horse and donkey is generally sterile, this widely recognized vigor is expressed in the first generation (F1). However, in the absence of recombination between the two parental genomes, F1 hybrids can be expected to be phenotypically intermediate between their parents which could potentially restr...
Whitesell K, Stefanovski D, McDonnell S, Turner R.The stallion Breeding Soundness Examination (BSE), as proposed by the Society for Theriogenology, recommends that a stallion produce a minimum of one billion progressively motile, morphologically normal sperm (PMMNS) in the second of two ejaculates collected 1 h apart to be classified as a Satisfactory Prospective Breeder. With this in mind, the first objective of this study was to determine if the classification outcome of the traditional BSE differs depending on the methods used to evaluate sperm motility, morphology and concentration. We hypothesized that application of Computer Assisted ...
Martig S, Hitchens PL, Lee PVS, Whitton RC.Subchondral bone injuries often precede articular cartilage damage in osteoarthritis and are common in thoroughbred racehorses due to the accumulation of fatigue damage from high speed racing and training. Thus, racehorses provide a model to investigate the role of subchondral bone in joint disease. We assessed the association of horse and racing related factors and micro-CT based micromorphology of three separate subchondral bone layers with the initial stiffness and compressive fatigue life of bone plugs. Furthermore, we investigated three different definitions of fatigue failure of subchond...
Tocci R, Sargentini C, Martini A, Andrenelli L, Pezzati A, Benvenuti D, Giorgetti A.Foot quality is essential to the horse's movement. The barefoot approach favours the animal's welfare. Environment and selection determine hoof characteristics. Methods: Hoof characteristics of eight Anglo-Arabian (AA) and nine Haflinger (HA) horses were studied. After a preliminary visual analysis of feet, nail samples were collected after trimming for physico-chemical analysis. The parameters were submitted to analysis of variance. A principal component analysis and a Pearson correlation were used to compare mineral contents. Results: The hooves of both breeds were healthy and solid. The hoo...
Lancaster LS, Bowker RM, Mauer WA.Density and morphologic features of hoof wall tubules in horses' hooves are described. The sample population consisted of hooves (n=12) from both live and deceased adult horses. Full wall thicknesses of the hoof wall were prepared histologically from sites at the toe, medial quarter and lateral quarter. In defined areas, tubules were counted, and density was calculated across the three histologically defined areas of the stratum externum, stratum medium and stratum internum along with the descriptive morphologic features of the tubules. Morphologically, distinct zones were demarcated by varyin...
Li XY, Pape T, Zhang D.Species of Gasterophilus Leach are obligate parasites in domestic and wild equids and responsible for cosmopolitan gasterophilosis. Although with only eight species known so far, they have received considerable attention because of their significant veterinary and economic importance. Surprisingly, we found that G. flavipes (Olivier) is a valid species based on morphological characters from male, female and the egg, after spending half a century as a synonym of G. haemorrhoidalis (Linnaeus). In the present study, G. flavipes, G. haemorrhoidalis and G. inermis (Brauer), which are the three clos...
Nauwelaerts S, Allen WA, Lane JM, Clayton HM.Quantifying the dynamics of limb movements requires knowledge of the mass distribution between and within limb segments. We measured segment masses, positions of segmental center of mass and moments of inertia of the fore and hind limb segments for 38 horses of different breeds and sizes. After disarticulation by dissections, segments were weighed and the position of the center of mass was determined by suspension. Moment of inertia was measured using a trifilar pendulum. We found that mass distribution does not change with size for animals under 600 kg and report ratios of segmental masses to...
Gastal GD, Alves BG, Alves KA, Souza ME, Vieira AD, Varela AS, Figueiredo JR, Feugang JM, Lucia T, Gastal EL.The method of transportation and the conditions imposed on the ovarian tissue are pivotal aspects for the success of ovarian tissue cryopreservation (OTC). The aim of this study was to evaluate the effect of the size of the ovarian tissue (e.g. whole ovary, biopsy size and transplant size) during different times of storage (0, 6, 12 and 24 h) on the structural integrity of equine ovarian tissue transported at 4°C. Eighteen pairs of ovaries from young mares (<10 years old) were harvested in a slaughterhouse and processed to simulate the fragment sizes (biopsy and transplant size groups) o...
Hitchcock PJ, Brown TM, Corwin D, Hayes SF, Olszewski A, Todd WJ.Examination of recently isolated cultures of three strains of Contagious Equine Metritis Organism grown on specially formulated, serum-free, clear typing medium revealed the presence of numerous colonial opacity variants. These colonies were prepared by a number of fixation and staining techniques and examined by scanning and transmission electron microscopy. Opaque and transparent phenotypes produced copious amounts of extracellular material compared with intermediate-opacity phenotypes which produced little or none. Also unique to intermediate colonies were numerous thin intercellular strand...
Demyda-Peyrás S, Bottrel M, Acha D, Ortiz I, Hidalgo M, Carrasco JJ, Gómez-Arrones V, Gósalvez J, Dorado J.The aim of this study was to evaluate the effect of different cooling rates on post-thaw quality of cryopreserved donkey spermatozoa. Eighteen ejaculates from six adult Andalusian donkeys (three ejaculates per donkey) were collected using an artificial vagina. Pooled semen samples (two ejaculates per pool) were divided into three aliquots, and frozen in Gent freezing extender using three different cryopreservation protocols (P): P1 (conventional slow freezing, as control): semen pre-cooled in an Equitainer for 2 h and frozen in liquid nitrogen (LN) vapour; P2 (controlled pre-freeze cooling r...
Bouillant AM, Becker SA.The successive steps of maturation of seven retroviruses from five species of farm animals and one retrovirus from a mouse were compared in cell cultures. The viruses included three type C oncoviruses, one spumavirus, and three lentiviruses. Although members of the 3 subfamilies shared some gross morphologic features such as budding on plasma membranes, core, and surface projections, differences were noted in the ultrastructural detail of these features. Type C oncoviruses did not show any structural differentiation in identifiable form in the cytoplasm as opposed to characteristic features ob...
Henderson SE, Santangelo KS, Bertone AL.To determine effects of various concentrations of retinoic acid (RA) or a synthetic RA receptor antagonist (LE135) on equine chondrocytes or bone marrow-derived equine mesenchymal stem cells (BMDMSCs) in monolayer cultures. Methods: Articular cartilage and BMDMSCs from 5 clinically normal horses. Methods: Monolayers of chondrocytes cultured in standard media and of BMDMSCs cultured in chondrogenic media were treated with RA at concentrations of 0, 0.1, 1, or 10 μM or LE135 at concentrations of 0, 0.1, 1, or 10 μM on day 0. On days 7 and 14, samples were analyzed for DNA concentration, chondr...
Egyptien S, Deleuze S, Ledeck J, Ponthier J.Stallion sperm analysis is indicated for infertility diagnosis, pre-sale expertise, production of fresh or frozen doses, and frozen straw quality control. Various collection methods are described, and numerous assays can be performed on semen. Determining an approach for each of these cases is challenging. This review aims to discuss how to obtain relevant clinical results, answering stallion owners' concerns. Semen can be collected with an artificial vagina on a phantom or a mare, by electro-ejaculation under anesthesia, or after pharmacological induction. The collection method influences the...
Lindholm A, Johansson HE, Kjaersgaard P.LINDHOLM, A., H.-E. JOHANSSON & P. KJÆRSGAARD: Acute rhabdomyolysis (“tying-up”) in standardbred horses. A morphological and biochemical study. Acta vet. scand. 1974, 15, 325–339. — Morphological, biochemical and histochemical changes were studied in muscle needle biopsy specimens (gluteus medius) from 59 standardbred trotters with acute clinical symptoms of the “tying-up” disease. All horses had increased levels of serum enzymes SGOT and SCPK. The biopsy specimens were taken at various intervals after onset of clinical symptoms (1–4 hrs., 18–24 hrs. and 2–20 days). Ry light...
Lane M, O'Donovan MK, Squires EL, Seidel GE, Gardner DK.Nutrient uptakes and metabolite production by equine morula and blastocyst stage embryos were determined by non-invasive microfluorometry. Equine morula took up equal amounts of both pyruvate and glucose. However, at the early blastocyst there was a small increase in glucose uptake and, by the expanded blastocyst stage, glucose was the predominant nutrient. Expanded blastocysts took up five times more glucose than pyruvate. Expanded blastocysts exhibited an exponential increase in glucose uptake and lactate production with respect to both diameter and surface area. As less than 50% of the gluc...
Richardson JD, Cripps PJ, Lane JG.Dental features are commonly expected to provide an accurate estimate of a horse's age. In this study the dentition of 434 thoroughbreds was photographed and the individual dental features documented, the true age of all the horses was known. For each dental feature the correlation with true age was determined. The eruption of the incisor teeth was the most consistent feature but it was not totally reliable. The presence of a hook on the upper corner incisor and Galvayne's groove proved to be of no value when estimating age and, of the attritional features studied, the dental star showed the h...
Shipton WA.The equine phycomycotic agent known commonly as Hyphomyces destruens or occasionally as Pythium gracile, is described as a new species Pythium destruens. Separation is on the basis of morphological features, temperature growth profiles, esterase/lipase activity, and carbohydrate utilization ability. P. diclinum (synonymous with P. gracile sensu Middleton) showed minor differences in vesicle, oospore and oogonium size from P. destruens. P. destruens grew at 40 degrees C on corn meal agar and hydrolysed esters of lauric and oleic acids. These abilities were not displayed by P. diclinum, but this...
Florence L, McDonnell SM.Despite growing interest in application natural models of hoof-maintenance in domestic horses, little data is available to describe natural conformation and proposed mechanisms of self-maintenance. Objective: Quantitatively describe hoof growth and wear during a period of 'self-trimming' within a herd of semi-feral ponies. Methods: Hoof length, growth and wear were measured for a sample of 40 animals during a period of 'self-trimming' from June through September, 2005. Results: For front hooves, mean toe lengths in July, August and September were significantly less than in June. For the hind, ...
Roland E, Stover SM, Hull ML, Dorsch K.To define a 3-dimensional (3-D) coordinate system with clear definitions of origins and axes relative to hoof anatomic features and determine whether solar surfaces of Thoroughbred racehorse hooves have geometric asymmetry in the mediolateral and dorsopalmar directions. Methods: Left forelimb hooves from 20 Thoroughbred racehorse cadavers. Methods: A right-handed 3-D coordinate axes system centered on the collateral sulci was defined for the left front hoof. Orthogonal distances of anatomic features from the dorsopalmar axis and the plane coincident with the ground were measured and compared b...
de Paz Cabello P, Chamorro CA, Sandoval J, Fernandez M.The mechanical papillae of the horse and cow were studied by scanning electron microscopy in order to determine their morphostructural characteristics and the differences between the two species. The horse has only thin, small and interlaced filiform papillae, while the cow shows robust and more ordered filiform papillae. Furthermore, the cow tongue presents conical and lenticular papillae surrounded by a papillary groove. A characteristic distribution of stratified scales and channeled tracts is observed in conical and lenticular papillae but not in the filiform papillae. The morphostructural...
Sells DM, Hildebrandt PK, Lewis GE, Nyindo MB, Ristic M.The ultrastructure of the etiological agent of equine ehrlichiosis, Ehrlichia equi, was studied in equine peripheral leukocytes. The organisms occurred within membrane-lined cytoplasmic vacuoles of neutrophils and eosinophils. Ovoid, round, and rod-shaped profiles were observed. From 1 to 33 organisms were present in a thin-section profile of a cytoplasmic vacuole. Many cells contained multiple organism-containing vacuoles. The organisms had a cell wall and plasma membrane, and internally they consisted of electron-dense and lucid areas. A great variation in size was observed. The morphologica...
Diekmann I, Blazejak K, Krücken J, Strube C, von Samson-Himmelstjerna G.Surveillance of Strongylus vulgaris and other Strongylus spp. in equids is important for targeted intervention in parasite control, requiring reliable routine diagnostic methods. Objective: Comparing morphological examination and PCR analyses of larval cultures to identify Strongylus spp. species based on German diagnostic samples from 2018. Methods: Method comparison. Methods: During the routine diagnostic investigations, in total 712 strongyle-egg positive equine faecal samples were cultured. Third-stage larvae (L3) were morphologically differentiated. For molecular validation, samples were ...
Almahbobi G, Papadopoulos V, Carreau S, Silberzahn P.Two ultrastructurally distinct types of Leydig cells were observed in the equine testis. Whereas the adult testis exhibited both postpubertal and adult Leydig cells, the testis of the pubertal horse contained only the postpubertal type, and that of the aged horse contained only the adult type. However, Percoll-purified testicular preparations from pubertal, adult, and aged horses all exhibited two distinct Leydig cell populations. The quantitative distribution and the functional characteristics of these Leydig cell populations (ability to bind human chorionic gonadotropin [hCG] and increase of...
Cheal EJ, Snyder BD, Nunamaker DM, Hayes WC.The objective of this investigation was to examine the stress-morphology relationships for trabecular bone around implants with different surface characteristics. Stainless steel spheres with either a polished surface or a sintered-bead porous coating were implanted unilaterally into equine patellae and maintained for a 6 month period. Stereological methods were used to quantify the trabecular bone morphology and finite element analyses were performed to predict the trabecular bone stresses. In general, the remodeling response around the smooth implants was greater than that around those porou...
Staszyk C, Gasse H.The distribution and arrangement of oxytalan fibres were examined in periodontal specimens of cheek teeth from seven horses. Oxidation prior to aldehyde fuchsin exposition permitted a selective staining of the oxytalan fibres, which are a distinct component of the elastic fibre system. On three horizontal levels of the periodontium--(a) subgingival, (b) middle third and (c) apical--two oxytalan fibre groups were shown histologically: 'blood vessel-related' and 'independent' oxytalan fibres. In levels a and b, both groups were arranged in a typical occluso-apical alignment along the reserve cro...
Passman SN, Cheetham J, Bonassar LJ, Ducharme NG, Rawlinson JJ.Upper airway obstruction is a common problem in the performance horse as the soft tissues of the larynx collapse into the airway, yet there is a paucity of information on biomechanical properties for the structural cartilage components. Objective: To measure the geometry and compressive mechanical properties of the hyaline cartilage to improve understanding of laryngeal function and morphology. Methods: A total of 11 larynges were harvested from Thoroughbred and Standardbred racehorses. During gross dissection, linear dimensions of the cricoid were obtained. From both the cricoid and arytenoid...
Selim SA, Soliman R, Osman K, Padhye AA, Ajello L.Isolation of Histoplasma farciminosum from five horses, showing typical signs of histoplasmosis farciminosi (epizootic lymphangitis) was successfully attempted. The mycelial form of H. farciminosum was isolated on Sabouraud dextrose agar enriched with 2.5% glycerol, brain heart infusion (BHI) agar enriched with 10% horse blood and PPLO dextrose glycerol agar. The last medium proved to be the most effective, both for primary isolation and subculturing of the fungus. It was found that on primary isolation, the lag phase of the mycelial form of the fungus was relatively long, involving 4-8 weeks ...
Kammergruber E, Rahn C, Nell B, Gabner S, Egerbacher M.The morphology of the corneal epithelium in two age groups of horses is described. Distribution patterns of proliferation-, differentiation-, stem cell-associated markers and cell junction proteins were assessed. Methods: Corneal samples from 12 horses (six foals and six adult horses) were analyzed after H&E staining and immunohistochemistry using the following antibodies: E-cadherin, β-catenin, Connexin 43 (Cx43), tight junction protein 1 (TJP1), cytokeratin (CK) 14, CK 19, CK 3, CK 10, vimentin, Ki67, p63, nerve growth factor (NGF), ABCG2, and epithelial growth factor receptor. Semiquan...
López-Plana C, Sautet JY, Pons J, Navarro G.Quantitative measurements were made on cross-sectional preparations of the distal part of the recurrent laryngeal nerve (RLN) from nine young mixed-breed horses to establish reference values for the total number of myelinated fibres, mean fibre diameter and percentage of thickest fibres (over 9.5 microns) and to delineate diameter distribution curves. The total number of myelinated fibres, mean fibre diameter and percentage of thickest fibres for the left RLN were significantly lower than those of the right RLN (P < 0.005). The distribution of fibres was unimodal. The fibre diameter ranged ...
Dabareiner RM, Snyder JR, White NA, Pascoe JR, Harmon FA, Gardner I, Woliner MJ, Pinney D, Sullins KE.Microvascular permeability of the jejunum of clinically normal equids and microvascular permeability associated with 60 minutes of ischemia (25% baseline blood flow) and subsequent reperfusion were investigated. Eight adult horses were randomly allotted to 2 equal groups: normal and ischemic/reperfusion injury. Lymphatic flow rates, mesenteric blood flow, and lymph and plasma protein concentrations were determined at 15-minute intervals throughout the study. Microvascular permeability was determined by estimates of the osmotic reflection coefficient, which was determined when the ratio of lymp...
Russo D, Bombardi C, Castellani G, Chiocchetti R.Spinal ganglion (SG) neurons have been widely described in rodents, and classified according to various criteria. On the basis of such studies, many features of rodent SG neurons have become benchmarks to classify these cells. However, these traits cannot be confirmed in all other species. In the present study, horse SG neurons were morphometrically and neurochemically characterized by detecting the neuronal markers calcitonin gene-related peptide (CGRP), substance P (SP), neuronal nitric oxide synthase (nNOS) and isolectin B4 (IB4) from Griffonia simplicifolia. Moreover, spinal cord staining ...
Muylle S, Simoens P, Lauwers H, Van Loon G.The accuracy of ageing horses by their dentition was assessed by comparing the dental features with the known dates of birth of 212 trotter horses and 189 Belgian draft horses. The horses ranged in age from two to 25 years. In both breeds it was observed that the shedding of the incisors and the appearance of the dental stars were the most reliable features for age determination. In young animals, the dental configuration was similar in both breeds. With increasing age the incisor teeth of draft horses were more liable to abrasion than those of trotter horses. The sequential changes in appeara...
Paradowska-Dogan A, Fernandez A, Bergmann M, Kretzer K, Mallidis C, Vieweg M, Waliszewski P, Zitzmann M, Weidner W, Steger K, Kliesch S.Highly compacted sperm DNA in protamine toroids and a minor fraction of nucleohistones are prerequisites for the efficient transmission of the paternal genome into the oocyte at fertilization. The objective of this study was to evaluate whether protamines might serve as a prognostic factor for stallion fertility. In situ hybridization detected specific expression of P1 mRNA in the cytoplasm of stage I to VII spermatids, whereas comparable immunohistochemical stainings showed that protein expression was delayed till elongating spermatids in differentiation stages III to VIII. No staining was de...
