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.
Watkins JP, Auer JA, Gay S, Morgan SJ.Full-thickness defects were surgically created in the superficial digital flexor tendons of the front limbs of 20 horses. Tissues formed within the defect were evaluated histologically, and the collagen composition of the tissue was determined by immunofluorescence. Transformation occurred from loose fibrillar areas of types I and III collagen and pericellular types IV and V collagen to dense bundles of type I collagen fibers. Loose fibrillar areas of types I and III collagen were present after 24 weeks. Histologically, in horses killed after 2 weeks, the tissue within the defect was a randoml...
Takai S, Kawazu S, Tsubaki S.An enzyme-linked immunosorbent assay (ELISA) was used to diagnose Corynebacterium (Rhodococcus) equi infection in foals. In tests done with different antigen-extraction procedures (sodium dodecyl sulfate, sodium deoxycholate, polyoxy-ethylene [9] p-tert-octylphenol, polyoxy-ethylene [9-10] p-tert-octylphenol, sonification, homogenization, and heat treatment at 121 C), Tween 20 was a satisfactory reactive antigen. Using hyperimmune rabbit sera or infected foal sera, we investigated the specificity and the sensitivity of the ELISA with the Tween 20 antigen of the different serotypes or of the is...
Matsui K.Fetal electrocardiogram in a twin pregnancy of a Thoroughbred horse was recorded. Two colts were born alive at 340 days of gestation. One was healthy but the other was growth-retarded. Both fetal heart rates decreased similarly with gestational age, but the discrepancy was noted from 4 days before parturition. The higher heart rate seemed to be obtained from the growth-retarded colt. Maternal heart rate increased gradually with the advancement of gestational period and then increased prominently during the last 2 weeks before parturition.
Bertone JJ, Dill SG.An ingested metallic foreign body migrated from the stomach and induced restrictive pericarditis in a horse. Necropsy revealed chronic abdominal and acute thoracic lesions. Although rare, ingested foreign body migration should be considered in the differential diagnosis of body cavity disease in horses.
Rhodes JB, Schweitzer D, Ogg JE.Non-O1 Vibrio cholerae was isolated from a horse (Equus caballus), a lamb (genus Ovis), and two American buffalo (Bison bison) suffering from enteric disease in the western part of Colorado. In 1981, a foal died of apparent respiratory failure. Necropsy findings included heart failure and gastroenteritis. V. cholerae serovar 347 (Smith) was isolated from the colon of this animal. V. cholerae serovar 27 (Smith) was isolated in 1983 from the intestine of a feedlot lamb suffering from pneumonia and severe watery diarrhea. In 1984, an enteric disease occurred in a herd of American bison. The sick ...
Srivastava SK, Barnum DA.The ability of either formalin-treated or heat-inactivated whole Streptococcus equi cell vaccines or partially purified M-protein of S. equi to give rise to protective antibody levels was studied in Standardbred foals by serological means. Two commercial preparations, i.e. a beta-propiolactone killed whole S. equi cell bacterin and a cell-free extract of S. equi cells were included in the study. The mean passive hemagglutination antibody titers (10 X log2) in sera of foals given either four doses of formalin-treated whole cell vaccine or an initial dose of formalin-treated followed by three do...
Blanchard TL, Elmore RG, Kinden DA, Berg JN, Mollett TA, Garcia MC.Fifteen pony mares were assigned to 1 of 3 treatment groups after foaling: Group 1, 35 ml of sterile saline solution was infused into the uterine lumen within 24 hours after parturition (6 mares); group 2, 300 mg of Escherichia coli endotoxin was infused into the uterine lumen within 24 hours after parturition (6 mares); and group 3, 300 mg of E coli endotoxin was infused into the uterine lumen between 72 and 96 hours after parturition (3 mares). Rectal temperatures were taken at -1, -0.5, 0, 0.5, 1, 1.5, 2, 3, 4, and 5 hours after treatment. Venous blood samples were also taken at these times...
Prescott JF, Sweeney CR.Combined antimicrobial drug treatment was recommended for foals with Corynebacterium equi pneumonia. The preferred combination is orally administered erythromycin estolate (25 mg/kg of body weight, QID) plus rifampin (10 mg/kg, BID). Erythromycin estolate also can be combined for synergistic effect with sodium benzyl penicillin given IV (100,000 IU/kg, QID) or with ampicillin given IV (11 to 15 mg/kg, QID). A third choice is sodium benzyl penicillin IV with gentamicin IM (2.2 mg/kg, TID) or with kanamycin IM (10 mg/kg, QID). Gentamicin should be combined with penicillin G or ampicillin and not...
Sweeney CR, Divers TJ, Benson CE.Anaerobic bacteria are important and overlooked bacterial pathogens of the lower respiratory tract in horses. Twenty-one of 46 horses with pleuropneumonia had anaerobic bacteria isolated from pleural fluid or from tracheobronchial aspirate. Bacteroides oralis and B melaninogenicus were the anaerobes most frequently isolated. Survival was significantly less for horses from which anaerobes were isolated than for horses from which anaerobes were not isolated. Putrid odor was associated with the pleural fluid and/or breath in 62% of the horses from which anaerobes were isolated. In these horses, t...
van der Velden MA, Schuitemaker EA.The aetiology, clinical symptoms and treatment of equine periodic ophthalmia are discussed. Particular attention is paid to the possible role in aetiology of Onchocerca cervicalis microfilariae. Corticosteroids and atropine are the most important therapeutic drugs.
Forster HV, Pan LG, Flynn C, Bisgard GE, Hoffer RE.We determined whether the [CO2] in the upper airways (UA) can influence breathing in ponies and whether UA [CO2] contributes to the attenuation of a thermal tachypnea during periods of elevated inspired CO2. Six ponies were studied 1 mo after chronic tracheostomies were created. For one protocol the ponies were breathing room air through a cuffed endotracheal tube. Another smaller tube was placed in the tracheostomy and directed up the airway. By use of this tube, a pump, and prepared gas mixtures, UA [CO2] was altered without affecting alveolar or arterial PCO2. When the ponies were at a neut...
Zink MC, Yager JA, Prescott JF, Wilkie BN.Bronchoalveolar lavage was performed 5 times, sequentially, on 3 healthy foals while each foal was 6 to 63 days of age. Phagocytosis and bactericidal assays were performed on recovered alveolar macrophages. Corynebacterium equi and alveolar macrophages at a ratio of 10:1 were incubated for 1 hour in medium containing 1% heat-inactivated rabbit anti-C equi serum. After incubation, greater than 90% of the alveolar macrophages contained at least 1 ingested bacterium and each alveolar macrophage contained 9.4 +/- 1.0 bacteria (mean +/- SE). After alveolar macrophages and C equi were incubated for ...
Ruoff WW, Sams RA.The pharmacokinetics and bioavailability of cephalothin given to 6 horse mares at a dosage level of 11 mg/kg of body weight IV or IM were investigated. The disposition of cephalothin given IV was characterized by a rapid disposition phase with a mean half-life of 2.89 minutes and a subsequent slower elimination phase with a mean half-life of only 14.7 minutes. The mean residence time of cephalothin was 10.6 +/- 2.11 minutes. The total plasma clearance of cephalothin averaged 13.6 ml/min/kg and was caused by metabolism and renal elimination. Renal clearance of cephalothin averaged 1.32 ml/min/k...
Rousselle JC, Gillet G, Fillion G.The solubilization of the serotonergic 5HT1 and 5HT3 sites was performed with digitonin and sodium cholate at 1% (final concentration). Two binding sites for [3H]5HT were observed on rat or horse brain synaptosomal membranes solubilized with these detergents. The corresponding dissociation constants (KD) were 1-3 nM and 13-30 nM respectively. These values were closely similar to those corresponding to 5HT1 and 5HT3 sites located in intact membranes. The solubilized sites specifically bound 5HT. The effect of GTP decreasing the binding to 5HT1 sites was lost on solubilized 5HT1 sites; it was re...
Giudicelli J, Boudouard M, Delqué P, Vannier C, Sudaka P.Neutral alpha-D-glucosidase (alpha-D-glucoside glucohydrolase, EC 3.2.1.20) from horse kidney brush-border membranes was solubilized using Emulphogene BC 720 and purified by an affinity chromatography technique. The enzyme preparation (390-fold purified), which was free of other known microvillus hydrolases, exhibited one precipitate line in crossed immunoelectrophoresis and migrated as a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Several criteria (charge-shift crossed immunoelectrophoresis and hydrophobic chromatography) revealed the purified detergent form of t...
Todhunter RJ, Brown CM, Stickle R.Five horses with retropharyngeal (RP) infections had clinical signs of dysphagia and/or dyspnea. Diagnosis was confirmed, using pharyngeal endoscopy and lateral radiography of the pharynx. One horse responded to surgical drainage of a RP abscess and was sound at light work. One horse responded to medical management after the site of infection was surgically explored. Two horses recovered after medical management; the RP abscess of 1 of these 2 horses ruptured spontaneously into the pharynx and the other horse became racing sound. The fifth horse remained dysphagic and had left laryngeal hemipl...
Ahmad F.The denaturation of horse metmyoglobin by guanidine hydrochloride was studied at pH 6.4 and 25 degrees C. Measurements of both the peptide circular dichroism and the absorbance in the Soret region suggest that the extent of renaturation strongly depends on the time interval during which the protein is exposed to concentrated solutions of the denaturant. From the equilibrium measurements of the absorption in the Soret region, it is concluded that the unfolding of metmyoglobin is complex. This is further supported by kinetic studies of denaturation which suggest the occurrence of the least four ...
Bixby-Hammett DM.In brief: In a two-year study of the estimated 13,428,000 hours of horse activities by 18,408 US Pony Clubs (USPC) members aged 6 to 21 in scheduled supervised programs, there were 64 accidents resulting in 88 injuries in 16 areas of the body. The head/face was the area most often injured (27.27%), and bruise/abrasion was the most common type of injury (28.26%). Cross-country riding was the most dangerous event (42.31%). Unexpected actions of the horse caused many accidents-25% occurred when the horse bucked and threw the rider, 23.08% when the horse refused a jump, and 17.31% when the horse f...
Nolan AM, Hall LW.The use of propofol, solubilised in a non-ionic emulsifying agent, for the induction and maintenance of anaesthesia in experimental ponies was assessed. Pilot studies revealed that premedication with xylazine (0.5 mg/kg bodyweight [bwt]) intravenously (iv) followed by propofol (2.0 mg/kg bwt) iv provided a satisfactory smooth induction. Two infusion rates (0.15 mg/kg bwt/min and 0.2 mg/kg bwt/min) were compared for maintenance of anaesthesia. An infusion rate of 0.2 mg/kg/min produced adequate anaesthesia in these ponies. Cardiovascular changes included a decrease in arterial pressure and card...
Cutmore CM, Snow DH, Newsholme EA.The effect of physical training on the in vitro activities of key enzymes that provide quantitative information on the maximum capacities of anaerobic and aerobic metabolism has been investigated in the gluteal muscle of the horse. Training had no effect on the activities of 6-phosphofructokinase or creatine kinase, suggesting that there was no effect on the capacity of anaerobic metabolism in this muscle. However, the activities of hexokinase and citrate synthase were increased, indicating that training increased the capacity of aerobic metabolism. For comparative purposes, muscle fibre compo...
Monath TP, Sabattini MS, Pauli R, Daffner JF, Mitchell CJ, Bowen GS, Cropp CB.Serologic surveys of wild and domestic birds, wild mammals, and horses were conducted during arbovirus field studies in Argentina from 1977 through 1980, a non-epizootic interval. The prevalence of neutralizing antibodies to eastern equine encephalitis (EEE) was consistently higher than to western equine encephalitis (WEE) virus in all species and all areas. The presence of antibodies in short-lived avian species and in young unvaccinated horses and the demonstration of seroconversions in horses during the period, indicated that these viruses are either enzootic in, or annually reintroduced in...
Richer CL, Romagnano A.Both dynamic G-banding and cell synchronization produced by bromodeoxyuridine (BrdU), were applied to equine chromosomes. BrdU incorporated during the first half of the S-phase is taken up into the R-bands that are early replicating. These bands, which have incorporated BrdU, cannot contract as usual and remain elongated; only the other regions of the chromosome, i.e., the G-bands, contract normally and are sharply defined. BrdU also can be used for cell synchronization. The addition of BrdU in a high concentration, 15 hours before harvest, and its removal 11 hours later, has two effects: init...
Sanders-Shamis M.Perirectal abscesses were diagnosed retrospectively in 6 horses treated for colic. The abscesses caused colic in the horses by producing an extraluminal obstruction that led to fecal impaction. The abscesses were diagnosed by rectal palpation and aspiration of exudate from the masses and were drained surgically. In horses in which the abscess involved abdominal organs, peritonitis developed.
Orton RK, Hume ID, Leng RA.Rates of growth were measured in two-year-old (Experiment 1) and nine-month-old (Experiment 2) horses fed high (12 or 14 per cent) or low (6 or 8 per cent) crude protein diets with one of two levels of exercise (0 or 12 km trotting per day at 12 km/h). In the non-exercised horses feed intakes and growth rates were greater on the high than on the low protein diets. Exercise increased feed intakes and growth rates of horses on the low but not the high protein diets, so that in the exercised groups there were no significant differences in feed intakes or growth rates between the horses on the two...
Auer JA.Bilateral angular limb deformities of the metacarpo/metatarsophalangeal regions in 2 foals are discussed. Periosteal transection was used to correct the deformity in both foals. In one foal, only the right forelimb was treated because the deformity in the left forelimb did not appear to warrant surgery. Subsequently, an angular limb deformity, which could have been prevented, developed in the left forelimb. A third foal developed a deformity in the proximal phalanx after periosteal transection of the distal third metatarsal bone.
Beech J, Garcia M.Cortisol, triiodothyronine (T3), thyroxine (T4), insulin, and glucose responses to thyrotropin-releasing hormone (TRH) were evaluated in 12 healthy, mature horses and in 7 horses and 4 ponies with clinical signs of pituitary adenoma (PA). Within 1 hour after TRH administration, the increase in T3 and T4 was similar in healthy horses and animals with PA. Plasma cortisol in the group with PA increased (P less than 0.05) within 0.25 hours after TRH administration, and remained increased for 1.5 hours. In the control group, a significant increase in plasma cortisol concentrations did not develop a...
Flynn C, Forster HV, Pan LG, Bisgard GE.The objective of this study was to determine the role of hilar nerve (lung vagal) afferents in the hyperpnea of exercise. Ten ponies were studied before and 2-4 wk and 3-12 mo after sectioning only the hilar branches of the vagus nerves (HND). After HND, lung volume feedback to the medullary centers was attenuated as indicated in the anesthetized state by 1) attenuation or absence of the Hering-Breuer inflation reflex (P less than 0.01) and 2) attenuation of the lengthened inspiratory time (TI) when the airway was occluded at end expiration (P less than 0.01). Moreover, after HND in the awake ...
Dumasia MC.The in vivo biotransformation of metoprolol tartrate in the thoroughbred racehorse was studied after administration of a single oral dose. Metoprolol and its basic and bifunctional phase I metabolites were isolated from urine and plasma using mixed mode solid phase extraction (SPE) cartridges. The isolates were derivatised as trimethylsilyl ethers and analysed by capillary column gas chromatography--positive ion electron ionisation and ammonia chemical ionisation mass spectrometry. Metabolism was primarily confined to the oxidative transformations of the p-(2-methoxy)ethyl substituent. Metopro...
Johnson SE, Barshick MR, Gonzalez ML, Riley JW, Pelletier ME, Castanho BC, Ealy EN.Strenuous exercise can cause tissue damage, leading to an extended recovery period. To counteract delayed post-exercise recovery, a commercial product containing L-carnitine (AID) was tested in adult horses performing consecutive exercise tests to exhaustion. Fit Thoroughbreds were administered an oral bolus of placebo (CON) or AID prior to performing an exercise test to exhaustion (D1). The heart rate (HR) and fetlock kinematics were captured throughout the exercise test. Blood was collected before, 10 min and 1, 4 and 6 h relative to exercise for the quantification of cytokine (1, 8, 10, ) g...
Ras-Noryńska M, Sokół R.Infections caused by nematodes of the subfamily Cyathostominae affect nearly 100% of pastured horses. Despite of an absence of pronounced symptoms, cyathostominosis can have very serious health consequences. The aim of this study was to monitor changes in total protein levels and concentrations of selected microelements and macroelements in the blood of horses before and after ivermectin treatment. In healthy horses infected by the studied parasites, total blood protein levels were below the physiological norm, but iron (Fe), magnesium (Mg), calcium (Ca) and phosphorus (P) concentrations were ...
Becht JL, Page EH, Morter RL, Boon GD, Thacker HL.Serological evidence with or without clinical signs of neonatal isoerythrolysis was experimentally produced in 6 of 8 foals born to mares allo-immunized with washed erythrocytes from the stallion. Blood group antigens were determined in all mares, stallions and foals, and the incompatible antigenic factor(s) responsible for the disease were defined. In 5 of 8 foals born to alloimmunized mares, a single antigenic factor difference accounted for the erythrocyte incompatibility between mare and foal. The erythrocyte antigen suspected as the most responsible for isoerythrolysis observed was A1. Ag...
Raeside JI, Gofton N, Liptrap RM, Milne FJ.Direct connection of the artery of a fetal ovary to the carotid artery of the mare allowed collection of a large volume of blood over a 30-min period. Extraction of steroids and their fractionation was followed by separation of the steroids by alumina adsorption chromatography, and Sephadex LH-20 and Celite partition chromatography. Further resolution of the material by HPLC led to the identification of dehydroepiandrosterone (DHA) by nuclear magnetic resonance and mass spectrometry. Other compounds were isolated, which remain to be identified fully, but in the 8th month of pregnancy the princ...
Harkins JD, Robinson NE, Woods WE, Lehner AF, Smith MD, Gates RS, Fisher M, Tobin T.Clenbuterol, a beta2 agonist/antagonist, is the only bronchodilator approved by the US Food and Drug Administration for use in horses. The Association of Racing Commissioners International classifies clenbuterol as a class 3 agent, and, as such, its identification in post-race samples may lead to sanctions. Anecdotal reports suggest that clenbuterol may have been administered by intratracheal (IT) injection to obtain beneficial effects and avoid post-race detection. The objectives of this study were (1) to measure the pharmacological efficacy of IT dose of clenbuterol and (2) to determine the ...
Chatfield JA, Dewell R, Miranda AJ, Wilcox S, Vannieuwenhoven TJ.To describe on-site veterinary medical care for working dogs and horses deployed for the 2012 Republican National Convention (RNC) in Tampa, Fla, August 24 to 30, 2012. Methods: Retrospective case series. Methods: 130 dogs and 45 horses. Methods: Data collected included breed, age, history, task assignment, reason for evaluation, and physical examination findings. A patient encounter report was recorded each time an animal was seen by veterinary staff for a physical evaluation. Results: 46 of the 130 (35%) dogs and all 45 (100%) horses underwent at least 1 on-site veterinary evaluation, for a ...
Atwill ER, Mohammed HO, Lopez JW, McCulloch CE, Dubovi EJ.To locate counties within New York state with a high seroprevalence among the equine population, to determine host, management, and environmental factors that were associated with seropositivity to Ehrlichia risticii, and to determine evidence for arthropod- or helminth-mediated transmission of E risticii to horses. Methods: Cross-sectional study. Methods: A random sample of 3,000 of the 39,000 equine operations in New York state was selected, and 2,587 horses from 511 operations were tested. Methods: Blood samples were collected from horses and tested for seropositivity, using the indirect fl...
Irvine CH, Turner JE, Alexander SL, Shand N, van Noordt S.In mares, dioestrous FSH profiles based on once-a-day sampling are variable; however, the pulsatility of plasma FSH, which has been suggested by limited windows of intensive sampling, may contribute to this variability. Jugular blood from six mares was sampled at 4 h intervals throughout an ovulatory cycle to determine cyclic FSH and LH patterns more accurately and to measure gonadotrophin pulse frequency during dioestrus. Synchronous pulses of FSH and LH occurred regularly in all mares between day 4 and day 12 (ovulation = day 0) with a mean (+/- SEM) frequency of 1.9 +/- 0.1 (FSH) or 1.6 +/-...
Turna Yilmaz O, Gunduz MC, Evkuran Dal G, Kurban I, Erzengin OM, Ucmak M.Doppler ultrasonography is a noninvasive technique which enables us to follow the physiologic and physiopathologic changes in blood flow in tissues. It is becoming an essential tool in veterinary medicine, especially in theriogenology. Twenty-seven Arabian mares were grouped by age ('young', 3-10 y, n=15; 'old', 19-23 y, n=12). The uterine arteries of the mares were examined using Doppler ultrasonography when an ovarian follicle ≥35mm was visible (Day -1). After these measurements, human chorionic gonadotropin (hCG; 2500IU) was administered to 14 mares selected randomly. One day later (Day 0...
Golzari K, Kong Y, Reed SA, Posada-Quintero HF.The continuous monitoring of stress, pain, and discomfort is key to providing a good quality of life for horses. The available tools based on observation are subjective and do not allow continuous monitoring. Given the link between emotions and sympathetic autonomic arousal, heart rate and heart rate variability are widely used for the non-invasive assessment of stress and pain in humans and horses. However, recent advances in pain and stress monitoring are increasingly using electrodermal activity (EDA), as it is a more sensitive and specific measure of sympathetic arousal than heart rate var...
DeCarbo WT, Feldner BM, Hyer CF.Equine pericardium xenograft is now widely used to augment Achilles tendon repair. In this article, we describe the case of a postoperative complication in a healthy 37-year-old male who underwent primary repair, augmented with equine pericardium, of his acutely ruptured Achilles tendon. At 4 months postoperative, an indurated and fluctuant subcutaneous soft tissue reaction was noted at the repair site. Further questioning led the patient to recall having an allergy to horses, although it had been a very long time since he had experienced any symptoms related to the allergy and, as such, he fa...
Haider W, Brehm W, Keller H.An apparently unilateral cryptorchid stallion was referred to the clinic with a history of colic. In the course of laparotomy an ileus caused by strangulation of the small intestine was found and the horse was euthanized because of poor prognosis. During autopsy strictures and ectasia of the jejunum were found as well as hermaphroditism along with male phenotype. The frequency of cryptorchidism in the case of intersexuality is discussed.
Jaeschke G, Rudolph R.The literature contains about 500 cases of equine leucosis, though the reports are deposited in a great number of journals and vary considerably concerning particular topics. During the last years there has been a remarkable increase of publications about this syndrome in the equine. The clinical leucosis key recommended by us has been confirmed in principle considering the latest literature. In about 70 individual symptoms which can be clinically observed in equine with leucosis 11 can be considered as main symptoms because of their frequency; they are again classified in primary (lymph node ...
Rouette J, Cockram MS, Sanchez J, MacMillan KM.A study of musculoskeletal injuries in Standardbred racehorses on Prince Edward Island was conducted to determine the incidence and risk factors for injury. Monthly information was collected from 10 trainers and 153 Standardbred horses over a 12-month period. Seventeen new injuries were identified in pacers, representing a horse level incidence risk of 23% and an incidence rate of injury of 2.19 per horse-month at risk. Forty-one percent of the injuries occurred during a race, 53% during training and 6% during jogging. Fourteen horses had experienced a previous injury and 3 of these horses exp...
Smiet E.Lately there has been a tendency to discuss Equine Cushing's disease and its related phenomena, due to the amount of recently acquired research data. The author has composed a brief overview of the present situation emphasizing relevance for practitioners.
Martínez AC, Rivera L, Raposo R, García-Sacristán A, Benedito S.The effect of histamine (10(-9)-10(-3) M) on horse penile dorsal artery was evaluated. Precontracted vessels showed a biphasic response (relaxation-contraction) to histamine, while at basal tone, histamine only induced a contractile effect. The H1 receptor agonist, 2-pyridylethylamine (PEA) (10(-9)-10(-3) M), induced concentration-dependent relaxation in precontracted rings and provoked vasoconstriction at basal tone. Mepyramine (10(-9)-10(8) M), an H1 receptor antagonist, competitively antagonized the relaxant response to histamine (pA2 = 9.7) and PEA (pA2 = 9.2). At basal tone, mepyramine (1...
Côté MA, Blum KM, Burd MA.During artificial insemination of horses, it is important to accurately estimate the number of spermatozoa in each insemination dose. However, little research exists regarding sources of spermatozoa loss during collection and artificial insemination. Therefore, spermatozoal losses were quantified in the dismount loss (187.6×10(6)±62.5×10(6)spermatozoa), gel fraction (179.8×10(6)±61.7×10(6)spermatozoa), and the collection receptacle (136.1×10(6)±26.9×10(6)spermatozoa). Spermatozoal losses were examined in the centrifuge tube (25.8×10(6)±2.1×10(6)spermatozoa), AI pipette during the a...