Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Todhunter RJ, Wootton JA, Altman N, Lust G, Minor RR.Collagen type I and type II were purified from equine flexor tendon and articular cartilage, respectively. Equal amounts of these collagens were cleaved with cyanogen bromide, and 11 mixtures containing increasing proportions of type II collagen were separated in seven identical sodium dodecyl sulfate-polyacrylamide gels. The density of bands was measured in wet gels and the peak areas were used to form six ratios of peptide bands that had polynomial relationships with the known proportions of type I and type II collagen in the mixtures. Calibration curves for determining the proportion of typ...
Dalefield RR, Palmer DN.Thyroid tumours have been described as "moderately common" in horses, but diseases associated with them are rare and the actual incidence has not been reported. A survey of thyroids from 29 horses aged 12 to 32 years revealed gross lesions in 11 animals, all older than 17. Most lesions were microfollicular adenomas. There was no evidence that the horses suffered from long-standing iodine deficiency or diffuse hyperplasia. Adenomas were more common than hyperplastic nodules and it is unlikely that the former arose from the latter. One thyroid adenocarcinoma was discovered. Progression from thyr...
Mumford EL, Squires EL, Jasko DJ, Nett TM.A lack of pituitary LH stores has been implicated as the cause of seasonal anestrus and failure to ovulate during the spring transition period in mares. In this experiment, 40 mares were used to study the effects of GnRH, estrogen, and an estrogen-GnRH combination on increasing releasable pituitary LH. Mares were stratified based on their ability to secrete LH in response to a 950-micrograms challenge of GnRH (n = 10 per group) and then assigned to one of four treatment groups: 1) controls, given no treatment; 2) 1 mg of estradiol-17 beta in oil i.m. daily for 8 d; 3) 200 micrograms of GnRH an...
Nixon AJ, Cummings JF.Serial sections of bone and soft tissue from the metacarpophalangeal joints of 2 mature and 2 immature horses were evaluated for substance P immunoreactive sensory nerve fibers. Formalin-fixed specimens were sectioned, either nondemineralized or demineralized with formic acid or EDTA. Rabbit antiserum to substance P (SP) was used in the streptavidin-biotin-peroxidase complex method for immunolocalization of SP antigen, and staining with 3,3'-diaminobenzidine was used for permanent identification of SP fibers. Abundant sensory nerve fibers were identified in the joint capsule, synovial membrane...
Vittur F, Grandolfo M, Fragonas E, Godeas C, Paoletti S, Pollesello P, Kvam BJ, Ruzzier F, Starc T, Mozrzymas JW.Some aspects of the physiology of chondrocytes from horse articular cartilage were studied, since this animal model can be helpful in understanding arthritic processes. The replicative ability of articular chondrocytes, measured by the incorporation of [3H]thymidine, and their capacity of proteoglycan production, evaluated from the incorporation of [35S] sulfate, are very low. In addition, these cells do not differentiate in vitro as shown by the constant specific activity of alkaline phosphatase measured at different times in culture. Two types of potassium channels were identified by patch c...
Art T, Votion D, McEntee K, Amory H, Linden A, Close R, Lekeux P.Two randomly distributed groups of thoroughbred horses were compared during a 12-week period for their cardio-respiratory and metabolic adjustment to strenuous exercise, training and detraining. The horses were trained following the same standardized schedule and were regularly investigated using standardized treadmill exercise tests (SET) of increasing speed. After the first SET and during the whole experimental period, a group of 6 horses received a probiotic (Bioracing) once a day while a group of 5 horses received a placebo. All other conditions were similar for both groups. During each SE...
Murray A, Cottrell DF, Woodman MP.Equine grass sickness (EGS) is a pan-dysautonomia of horses that involves central and peripheral neuronal degeneration and ultimately depletion. This is the first reported functional study on the motility of equine intestine taken immediately post mortem from horses with EGS. Strips of smooth muscle from the small intestine of healthy and EGS-affected horses were suspended in an organ bath and their motility was measured isometrically. The activity of the cholinergic system was studied. Physostigmine enhanced the motility of all muscle strips. Tissues taken from horses suffering from acute gra...
Jaussaud P, Audran M, Gareau RL, Souillard A, Chavanet I.A plasma kinetic study of erythropoietin (EPO) was carried out in 4 horses after subcutaneous administration (30 IU/kg bwt) of recombinant human erythropoietin (rhEPO). At standardized intervals for 48 h before injection and for 60 h post-administration, the EPO plasma levels were determined with an immunoradiometric assay based on a sandwich technique. The peak plasma concentration (30-113 mIU/ml) was observed after a delay ranging from 6 to 9 h post-administration and the drug levels reached a physiological value around 60 h following rhEPO injection. Moreover, reference values for plasma EP...
Hochi S, Fujimoto T, Choi YH, Braun J, Oguri N.Immature equine oocytes were frozen-thawed with ethylene glycol (EG), 1,2-propanediol (PD) or glycerol (GL) in PBS and cultured to assess the rate of in vitro maturation (Experiment 1). Compact-cumulus oocyte complexes were collected from slaughterhouse ovaries and equilibrated for 10 min in the freezing medium containing 10% (V/V) cryoprotectant and 0.1 M sucrose. The 0.25-ml straws, loaded with 10 to 30 oocytes, were seeded at -6 degrees C and cooled to -35 degrees C at 0.3 degrees C/min before being plunged into liquid nitrogen. The straws were thawed rapidly in a 37 degrees C waterbath for...
Leder L, Bosshard HR.It has long been known that antibodies to cytochrome c can distinguish between closely sequence-related cytochromes c. Because the 3-D-structure of the polypeptide chain is virtually identical among eukaryotic cytochromes c, antibody specificity is directed against amino acid substitutions within a common polypeptide folding pattern. The question arises if the specificity is observed at the level of the 3-D-structure (conformational epitopes) and/or at the level of the primary structure (sequential epitopes). Using rabbit sera to horse cytochrome c, we show that discrimination against the host...
Calisher CH.Of more than 500 arboviruses recognized worldwide, 5 were first isolated in Canada and 58 were first isolated in the United States. Six of these viruses are human pathogens: western equine encephalitis (WEE) and eastern equine encephalitis (EEE) viruses (family Togaviridae, genus Alphavirus), St. Louis encephalitis (SLE) and Powassan (POW) viruses (Flaviviridae, Flavivirus), LaCrosse (LAC) virus (Bunyaviridae, Bunyavirus), and Colorado tick fever (CTF) virus (Reoviridae, Coltivirus). Their scientific histories, geographic distributions, virology, epidemiology, vectors, vertebrate hosts, transm...
Heiskanen ML, Hilden L, Hyyppä S, Kangasniemi A, Pirhonen A, Mäenpää PH.The first (1 to 3) sperm-rich fractions of the ejaculate were collected from 4 stallions using an open-ended vagina. The volume of the collected fractions was 12 +/- 8 ml with a density of 475 +/- 200 million spermatozoa/ml. Before freezing, the semen was diluted with a skim-milk based extender 1:1 to 1:8 (volume of semen: volume of extender), depending on the initial sperm concentration to achieve a final concentration of 100 million/ml. The total number of spermatozoa in an insemination dose ranged from 0.7 to 1 billion spermatozoa. Within 12 h after ovulation, 48 mares were inseminated in 7...
Delbeke FT, Debackere M.A high performance liquid chromatographic method to measure plasma and urine fenoprofen levels in equine biofluids is described. Liquid-liquid extraction with diethylether was used to isolate the drug from plasma and urine. The accuracy and reproducibility of the method were within acceptable limits over the concentration range 0-10 micrograms/mL and 0-20 micrograms/mL respectively from plasma and urine. Detection limits were 0.05 microgram/mL (2 mL plasma) and 0.2 microgram/mL (0.5 mL urine). This procedure was applied to ascertain the pharmacokinetics of a 3 g dose of fenoprofen calcium in a...
Ghram A, Chabchoub A, Turki I, Boussetta M, Ibn Amor H, Ghorbel A.A seroepidemiological survey was realized in the Nord-Est Tunisia to study the prevalence of complement fixing and neutralizing antibodies to equine rhinopneumonitis and viral arteritis of horse, respectively. Four hundred sera were tested, using complement fixation reaction and seroneutralization test. The results show that 8.75% of sera have antibodies to viral arteritis and only 1.25% are positive for equine rhinopneumonitis.
Ogawa Y, Kanno M, Shimizu Y, Suzuki M, Yoshimoto T.A 56-year-old man presented with an unusual cranial penetration injury due to a horse's hoof. The CT number of the hoof was 269, and thus clearly not that of a wooden fragment or bone. An emergency operation was performed to remove the foreign body. The operation went well, and no infection developed. Eight months later he could walk unaided and had only mild disorientation.
Häni H, Lang J, Ueltschi G.During archaeological excavations of the former knackers yard in Emmen (Canton Lucerne) skeletons and individual bones of more than 700 animals were recovered. 110 bone samples had lesions and were examined macroscopically and radiologically, 100 were from horses, 9 from dogs and only one from cattle. According to morphological and etiopathogenetical criteria, lesions are presented in the following groups: tooth irregularities (10), degenerative changes in bones and joints due to overload and aging (80), trauma and infection (10), other lesions (10). Over 80% of pathological bone samples prese...
López-Plana C, Sautet JY, Ruberte J, Sabaté D.Histochemical and morphometric parameters of the cricoarytenoideus lateralis muscle of the horse are presented. Using myosin ATPase staining after acid preincubation, 3 fibre types (I, IIA and IIC) were identified. Using NADH-TR staining, type I fibres showed high oxidative capacity, whereas type II fibres had high or low oxidative capacity. The type I to type II ratio was of 35:65. This ratio remained constant in the age range examined. Statistically significant (p < 0.01) differences were found in values for fibre size between groups of horses weighing more than 500 kg and less than 400 k...
Dippert KD, Jasko DJ, Seidel GE, Squires EL.Embryo recovery per ovulation has been shown to be lower in superovulated mares than in untreated controls. The objectives of this study were to 1) determine whether follicles stimulated with superovulatory treatment ovulate or luteinize without ovulation, 2) determine fertilization rates of oocytes in oviducts of superovulated and control mares, and 3) evaluate viability of early stage embryos from superovulated and control mares when cultured in equine oviductal cell-conditioned medium. Cyclic mares were randomly assigned to 1 of 2 groups (n=14 per group) on the day of ovulation (Day 0): Gro...
Cahill CM, Van der Kolk H, Goode JA, Hayden TJ.Highly purified and well-characterised preparations of equine prolactin and growth hormone from equine pituitary glands were employed to set up highly sensitive and specific homologous radioimmunoassays (RIA) for the measurement of hormone in horse plasma. The limit of sensitivity of the GH RIA was 1.2 ng/ml with mean intra- and inter-assay coefficients of variation (CV) of 6.6 and 10%, respectively. The sensitivity of the equine prolactin (ePRL) RIA was 0.5 ng/ml with mean intra and inter-assay CV of 9.1 and 15.6%, respectively. Dose-response curves of a crude pituitary gland extract and plas...
McDonnell SM, Odian MJ.This study is a part of our ongoing work toward developing pharmacological methods for enhancing and inducing ejaculation in stallions with ejaculatory dysfunction. We evaluated a combination treatment of imipramine hydrochloride followed 10 minutes later by xylazine hydrochloride for the induction of ex copula ejaculation. Eight pony stallions each underwent 6 treatment trials conducted at 4-day intervals. The trials were conducted in the animals' stalls, where they were observed for 90 minutes following treatment. To evaluate the effect of pretreatment sexual stimulation on the rate of ejacu...
Agius CT, Studdert MJ.This chapter describes the molecular and biological properties of equine herpesviruses (EHV)2 and EHV5. It highlights advances in the study of EHV2 and EHV5. The reclassification of EHV2 and EHV5 as gammaherpesviruses rather than betaherpesviruses has profound implications for future approaches to the study of the two equine herpesviruses. The chapter places emphasis on a comparison between the properties of EHV2 and EHV5 and those of other gammaherpesviruses, especially Epstein-Barr virus (EBV), which is the causative agent of infectious mononucleosis/glandular fever in humans. Studies of the...
Lin HC, Wallace SS, Robbins RL, Harrison IW, Thurmon JC.In 4 mares suffering from dystocia, general anesthesia was induced with xylazine (1.1 mg/kg, IV) and ketamine (2.2 mg/kg, IV) and maintained with continuous intravenous infusion of ketamine (2 mg/ml), xylazine (0.5 mg/ml) and guaifenesin (50 mg/ml) in 1 L of 5% dextrose. The duration of the procedure of these mares were 40, 45, 180, and 35 minutes, respectively. For procedures required more than 1 hour (Mare 3), the dose of ketamine and xylazine in the mixture was reduced to 1 mg/ml and 0.25 mg/ml, respectively. Average infusion rate of the mixture used to maintain anesthesia for each mare was...
Scott VH, Williams JM, Mudge MC, Hurcombe SD.To assess effects of body position on direct measurements of intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) in horses anesthetized with total intravenous anesthesia (TIVA). Methods: 9 healthy adult horses. Methods: Instrumentation in unsedated standing horses involved insertion of an arterial catheter for blood pressure measurements and 3 intraperitoneal cannulas (left flank, right flank, and ventral abdomen) for IAP measurements. Baseline values were measured for heart rate, respiratory rate, systolic arterial blood pressure, mean arterial blood pressure (MAP), diastoli...
Stack JD, Cousty M, Sanders R, David F.To describe our experience using intraoperative ultrasound for various conditions in horses. Methods: Retrospective case series. Methods: Horses (n=113). Methods: Medical records including surgical reports at 2 equine hospitals (2007-2013) were reviewed to identify ultrasound-assisted surgeries. The diagnosis, reasons for using intraoperative ultrasound, the technique employed, and the surgical procedure performed (e.g., synovial endoscopy, cut-down, resection, dissection, curettage, and implant placement/removal) were recorded for each surgery. Intraoperative ultrasound was used to mark the o...
Abdel-Gaber R, Al Quraishy S, Dkhil MA, Alghamdi J, Al-Shaebi E.Sarcocystosis is a parasitic disease caused by an intracellular protozoan parasite Sarcocystis belonging to the phylum Apicomplexa. These parasites have a requisite two-host life cycle. Recently, there are many Sarcocystis species that identified morphologically. In the present study, diaphragmatic muscle samples from the domestic horse (Equus caballus) were examined for Sarcocystis infection. The natural infection with sarcocysts was recorded to be 62·5% for only microcysts in the infected muscles. Molecular analysis using the 18S rRNA gene was conducted to swiftly and accurately identify th...
Dickie CW, Regnier JO.Myositis and septicemia caused by Acinetobacter calcoaceticus were diagnosed in a mare. The infection was characterized clinically by ventral swelling and edema, diarrhea, listlessness, and rectal temperature of 39.4 C. The mare was treated symptomatically for 2 days but died on the 3rd day. Conditions seen at necropsy were myositis, enteritis, typhlitis, colitis, and hepatitis. Lymph nodes were moderately enlarged throughout the body. Gross lesions in musculature were edema, scarring, petechiae, and an occasional exxhymosis. The enteritis was catarrhal, with excessive mucus and moderate hyper...
Müller Z.Semen of 16 stallions collected by the fractionated method and frozen in liquid nitrogen was used to inseminate 175 mares of different ages and in various reproductive conditions. Pregnancy was recorded in 91 mares of which 72 delivered a foal. Pregnancy followed by resorption occurred in another 10 mares and 9 aborted. The best results were obtained in the young primiparous and in older mares inseminated in the oestrous cycle that followed the post-partum oestrus. Overall, 64% of mares became pregnant and 56% gave birth to a living foal. The highest occurrence of fetal death and resorption we...
Freeman DE, Ross MW, Donawick WJ, Hamir AN.Balloon-tipped catheters were used to occlude the external carotid artery and its branches in nine horses with hemorrhage caused by guttural pouch mycosis. The internal carotid artery on the affected side was occluded simultaneously in four horses and had been occluded previously in two others. In three horses, a single balloon-tipped catheter was inserted in the external carotid artery beneath the floor of the guttural pouch and its tip was advanced blindly into distal branches. In one horse, the superficial temporal artery was occluded briefly during surgery by a balloon-tipped catheter so a...
Comino F, Giusto G, Caramello V, Pagliara E, Bellino C, Gandini M.In equine castration, application of a ligature on the spermatic cord to prevent complications such as haemorrhage and evisceration has been reported with controversial results. Characteristics of commonly used knots have not been studied. Objective: To compare the modified transfixing and giant knots and the emasculator in open and closed equine castration techniques. Methods: Ex vivo experiment. Methods: A total of 144 testicles were randomly assigned to 2 groups for open or closed castration. Both groups were divided into 3 subgroups of 18 specimens each: emasculator only, emasculator plus ...
Cuervo-Arango J, Newcombe JR.The objective of this study was to establish and characterize the relationship between the dose of cloprostenol (37.5, 250, 500 and 750 μg) and the age of the early corpus luteum (CL) (80, 88, 96, 104 and 112 h) on the luteolytic response of mares. Behavioural oestrus and ultrasonographic signs of return to oestrus were considered as the occurrence of full luteolysis. A total of 298 mares were divided into groups according to dose of cloprostenol and CL age. There was an effect of dose of cloprostenol (p < 0.001) and age of the CL at the time of treatment (p 0.05); and that of 500 similar...
Katila T.Altogether 156 equine endometrial biopsies were carried out during the post partum (p.p.) period: immediately after parturition until 15 days after foaling. The histological changes are described. The rapid restoration of the equine endometrium is remarkable. The destruction of the luminal epithelium is minor and regeneration takes place rapidly. Remnants of the placenta, the microcotyledons and desquamated cells, have disappeared by 5 p.p. The transformation of glands from a pronounced secretory pattern to normal appearance also takes only 5 days. The occurrence of neutrophils and lymphocytes...
Palme R, Entenfellner U, Hoi H, Möstl E.Non-invasive pregnancy diagnosis in mares by measuring faecal oestrogens has been performed over years with great accuracy. However, results have indicated breed-related differences in the amount of excreted steroids during late pregnancy. Therefore faecal samples were collected during the last 4 months of pregnancy of Thoroughbred (n = 10), New Forest pony (n = 9), Shetland pony (n = 10) and Iceland pony mares (n = 11). Concentrations of oestrogens, 20alpha-hydroxy- and 20-oxopregnanes were measured using enzyme immunoassays. Breed differences concerning both levels (though significant only i...
Alwan WH, Carter SD, Bennett D, May SA, Edwards GB.Degradation of cartilage in osteoarthritis of man results in the release of sulphated glycosaminoglycans, particularly keratan sulphate, into tissue fluids. A study was made to evaluate these markers for osteoarthritis in the horse. Synovial fluid and serum levels of keratan sulphate, measured by an ELISA-inhibition technique, and sulphated glycosaminoglycans measured by specific dye binding assay, were found to be significantly increased (P less than 0.001) in joints from horses with osteoarthritis, compared with normal joints. Synovial fluids from joints with infective arthritis also showed ...
Fisher D, Schliewert EC, Hooijberg EH.An endogenous adrenocorticotropic hormone (ACTH) concentration above the reference interval (RI) is commonly used as means for diagnosing equine pituitary pars intermedia dysfunction (PPID). Basal ACTH concentrations are highly dependent on photoperiod and RIs should be month- and location-specific. To date, no ACTH RIs have been specifically established for South Africa. This study aimed to determine geographically and seasonally relevant RIs for equine ACTH in the Gauteng province of South Africa. A longitudinal prospective study was conducted over twelve months to determine ACTH RIs for a r...
Gürelli G, Göçmen B.Species composition and distribution of large intestinal ciliates were investigated in the feces from 15 Turk rahvan horses, living in the vicinity of Izmir, Turkey. Twenty-two ciliate genera consisting of 36 species were identified. This is the first report on intestinal ciliates in Turk rahvan horses and no previously unknown species were observed. The mean number of ciliates was 14.2±13.9×10(4) cells ml(-1) of feces and the mean number of ciliate species per host was 9.9±7.1. No ciliates were observed in 2 horses. Bundleia and Blepharocorys were considered to be the major genera since th...
Wiklund M, Granswed I, Nyman G.To evaluate the effect of pulsed inhaled nitric oxide (INO) on arterial oxygenation in horses during abdominal surgery. Methods: Prospective, randomized, clinical trial. Methods: Thirty horses that underwent abdominal surgery at the University Animal Hospital in Uppsala, Sweden. Methods: Anaesthesia was induced according to a standard protocol - romifidine, butorphanol, diazepam and ketamine and maintained with isoflurane in oxygen. Fifteen horses were administered pulsed INO and 15 served as controls. After baseline data collection, pulsed INO delivery commenced. Arterial and venous blood wer...
Brown MP, Pool RR.Braided carbon fiber sutures were used to repair surgically transected or lacerated digital flexor tendons of 20 mature horses (10 experimental and 10 clinical cases). In addition, 4 experimental horses had tenectomies that were not surgically repaired; these served as controls for the horses with carbon-implanted tendons. Six of the 10 clinically affected horses were returned to their intended use; 2 were euthanatized because of complications and 2 were still recuperating. The experimental horses were euthanatized at 12 days and 1, 2, 4, 8, and 12 months. Tendon scars were structurally and fu...
Chesen AB, Rakestraw PC.To identify indications for and short- and long-term outcome of permanent tracheostomy performed in standing horses. Methods: Retrospective case series. Methods: 82 horses undergoing permanent tracheostomy. Methods: Data obtained from medical records included signalment, diagnosis, surgical technique, complications, use of the horse before and after surgery, and owner satisfaction. Follow-up information was obtained through a telephone questionnaire administered to owners. Results: Indications for permanent tracheostomy included nasopharyngeal cicatrix (n = 59), arytenoid chondropathy (55), an...
Hennessy SE, Fraser BS.Over a 3-year period between July 2008 and July 2011, 10 exploratory laparotomies were performed on foals in a Waikato referral facility in New Zealand. Results: Right dorsal displacement of the large colon (RDDLC) was identified during four exploratory laparotomies in three foals that presented for mild-to-moderate colic that was non-responsive to medical management. One foal required a repeat laparotomy 7 weeks post initial surgery, and RDDLC was again diagnosed. Methods: Right dorsal displacement of the large colon in foals. Conclusions: Further investigation may identify risk factors or ma...
Turrentine MA, Sculley PW, Green EM, Johnson GS.Two sibling miniature horses, a male and a female, had a normal 1-stage prothrombin time and a prolonged activated-partial thromboplastin time (APTT). The addition of as little as 5% of a normal equine plasma pool to the plasma samples of both horses shortened their prolonged APTT to within normal limits. Coagulation factor analysis revealed deficiencies in factor XII (12 and 13 U/dl, control population 77 to 128 U/dl), when determined with a feline factor XII-deficient plasma substrate, but normal concentrations (119 and 96 U/dl) when a human factor XII-deficient plasma substrate was used. De...
Lima JJ.Serum protein binding of the basic enantiomers of disopyramide were studied in several animal species. (S)-(+)-Disopyramide was more highly bound than the (R)-(-)-enantiomer to serum protein in the man, gorilla, and pig. The reverse was true in cow serum, and in serum and albumin from sheep. Enantioselective differences in binding were due to differences in association constants. No enantioselective differences in binding were observed in serum protein from horse and goat, or in albumin from cow and pig. Disopyramide was highly bound to two sites on horse albumin. The association constant char...
Deficiency of the necessary complex of micronutrients under abnormal nutrition structure creates a problem for the preservation of health and performance of the population. In this regard, it is very relevant to develop a science-based strategy for the consumption of traditional Yakut national food that have a high nutritional value and are able to satisfy the requirements of the human body in micronutrients. of the research was to investigate the content of selenium and zinc in the local foods which are most commonly consumed by the population of Yakutia. . The objects of study were meat (7-...
Jenkinson DM, Loney C, Elder HY, Montgomery I, Mason DK.Histological studies of the sweat glands of anhidrotic horses in the Hong Kong summer and under conditions of reduced thermal stress, both natural and controlled, were undertaken to determine if glandular regeneration occurs. Clinical data were collected for comparison with the histological results in each instance. Horses were assigned to one of three categories on the basis of the resulting change in the number of thin glandular profiles in a cooler environment. Group 1, which was classed as normal, had a low initial value, which was maintained. Group 2, typical of mild and moderately affect...
Kloppe LH, Varner DD, Elmore RG, Bretzlaff KN, Shull JW.A breeding trial was conducted to evaluate the effect of insemination timing on the fertility of mares bred with frozen/thawed equine semen. One stallion and 60 reproductively sound, estrous-synchronized mares were included in the study. Mares were assigned to one of three groups (n = 20): 1) insemination with fresh semen every other day during estrus from detection of a 35-mm follicle until ovulation, 2) insemination with frozen/thawed semen every day during estrus from detection of a 35-mm follicle until ovulation or 3) insemination with frozen/thawed semen once, within 6 h after ovulation. ...
Gehlen H, Puhlmann J, Merle R, Thöne-Reineke C.Auxiliary reins are commonly used for the training of riders and horses as well as in daily training. They are often criticized when used incorrectly, as they will not help and can harm the horse by causing overwork, accidents, and injuries, which harm the horse in the long term. They also often conceal causal rider problems while trying to achieve quick success. The aim of this paper was to investigate, with an online horse-owner questionnaire, which and how often auxiliary reins were used and whether they were used appropriately. Only participants who were currently using auxiliary reins wer...
Noue P, Bernabé J, Rampin O, Vidament M, Dumas T, Palmer E, Magistrini M.The sexual behavior of 42 stallions from French national and private studs was examined in two contexts: semen collection for artificial insemination (AI) and in-hand natural service (NS). Each stallion was observed twice in the same context. Erection and ejaculation latencies, the number of mounts leading to ejaculation, dismount latency and total breeding time were measured and compared between AI and NS. Mount without erection was rare (6/83 observations). Erection latency was 89+/-11s, and was not different between NS (62+/-22s) and AI (100+/-13s, P=0.128). Stallions ejaculated after eithe...
