"Foals" encompasses a stage in the lifecycle of equines with distinct physiological and developmental characteristics. Foals are young horses, typically under one year of age, undergoing rapid growth and development. They require specific nutritional, health, and management practices to support their transition to adulthood. This page compiles peer-reviewed research studies and scholarly articles that explore the growth, development, health challenges, and management practices associated with foals and horses, providing insights into their care and welfare across different life stages.
Neuhauser S, Palm F, Ambuehl F, Aurich C.In this study, effects of altrenogest treatment (0.088 mg/kg daily) given to mares during late gestation until parturition on the time and the process of foaling, neonatal adaptation and postnatal development were analysed. The number of animals was 6 in the treatment group and 7 in the control group. Gestational length tended to be shorter in mares given altrenogest. Birth weight of the foals and weight of the placenta did not differ between groups. The second stage of parturition was prolonged in the altrenogest-treated mares (p<0.05). Foals born to altrenogest-treated mares had a significan...
Olstad K, Cnudde V, Masschaele B, Thomassen R, Dolvik NI.Osteochondrosis (OC) is an important developmental orthopedic disease of human and equine patients. The disease is defined as a focal disturbance in enchondral ossification. In horses, the disturbance can occur secondary to failure of the blood supply to growth cartilage. Diagnosis of the early, subclinical stages that can clarify the etiology is currently confined to cross-sectional histological examination. The potential for micro-computed tomography (micro-CT) with angiography to detect early lesions of OC has not yet been investigated. Methods: Nine Standardbred foals bred from parents wit...
Lyons ET, Tolliver SC, Ionita M, Collins SS.Horse foals on five farms in Central Kentucky were used in field studies in 2007 evaluating activity of paste formulations of four compounds (fenbendazole-FBZ, ivermectin-IVM, oxibendazole-OBZ, and pyrantel pamoate-PRT) against internal parasites with emphasis on ascarids (Parascaris equorum). It has been well established the last few years that there is widespread resistance of P. equorum to ivermectin. The main purpose of the present research was to obtain current data on ascaridicidal activity of FBZ, OBZ, and PRT; also, to acquire further information on ascarid resistance to ivermectin. Ad...
Berlin D, Aroch I.Magnesium (Mg) and calcium (Ca) are the main divalent cations in the body. The free ionized fraction is the physiologically active form of both Mg and Ca. As ion-selective-electrode (ISE) analyzers are becoming widely used in veterinary practice it will be useful to establish reference intervals for horses. In the present study, reference intervals were established for ionized, total and the ratio of the ionized to total Mg and Ca concentrations in four horse groups: adults, neonatal foals, and pregnant and lactating mares, as well as in three sample types, whole blood, plasma and serum, using...
Hurcombe SD, Toribio RE, Slovis N, Kohn CW, Refsal K, Saville W, Mudge MC.Sepsis is an important cause for neonatal foal mortality. The hypothalamic-pituitary-adrenal axis (HPAA) responses to sepsis are well documented in critically ill humans, but limited data exist in foals. The purpose of this study was to evaluate the HPAA response to sepsis in foals, and to associate these endocrine changes with survival. Objective: Blood concentrations of arginine vasopressin (AVP), adrenocorticotropin hormone (ACTH), and cortisol will be higher in septic foals as compared with sick nonseptic and healthy foals. The magnitude of increase in hormone concentration will be negativ...
Myers CJ, Magdesian KG, Kass PH, Madigan JE, Rhodes DM, Marks SL.This retrospective study describes the use of and complications associated with parenteral nutrition (PN) administration to 53 equine neonates at the University of California Veterinary Medical Teaching Hospital. Medical records were examined and information obtained on signalment, physical examination, clinical diagnosis, outcome, total hospitalization time, insulin administration, microbiology culture results, other complications (i.e. thrombophlebitis) and necropsy findings. Complete blood count and serum biochemistry analytes, venous blood gas, serum electrolyte and glucose concentrations,...
Masuda T, Takakura A, Kobayashi S.Flight and avoidance reactions from human were examined using 168 postweaning Thoroughbred foals in 22 breeding farms. Further 114 yearlings of 168 foals were tested in the following summer. The foal handlings by the stabler were asked in questionnaire. The relationship between the behavioural reactions and the foal handling frequencies was analyzed. The flight reaction was estimated as the distance from the animal to a stranger when the animal began to flight away from his approach. The avoidance scores were set up from (1) (not resistant) to (5) (touch rejection) from human touching. In the ...
Chaffin MK, Cohen ND, Martens RJ.To determine the effect of azithromycin chemoprophylaxis on the cumulative incidence of pneumonia caused by Rhodococcus equi, age at onset of pneumonia, and minimum inhibitory concentration (MIC) of azithromycin for R equi isolates cultured from fecal and clinical samples. Methods: Controlled, randomized clinical trial. Methods: 338 foals born and raised at 10 equine breeding farms; each farm had a history of endemic R equi infections. Methods: Group 1 foals were control foals, and group 2 foals were treated with azithromycin (10 mg/kg [4.5 mg/lb], PO, q 48 h) during the first 2 weeks after bi...
Valette JP, Robert C, Denoix JM.The objectives of this study were to establish standards for growth and to model the evolution of wither height (WH) between birth and adult age in different breeds of sport- and race-horses. Therefore, 398 foals, then yearlings of three different breeds, were measured regularly between birth and 18 months of age. Linear and non-linear functions were compared for describing the growth in each breed group. The monomolecular, Gompertz, logistic and cubic models correctly estimated WH in the three breeds during the first 2 years (R2 = 0.99, s.e. 3.9 to 4.5) and better than the cubic and quadratic...
Sanchez LC, Giguère S, Javsicas LH, Bier J, Walrond CJ, Womble AY.Gastric tonometry is commonly used in humans as an assessment of intestinal mucosal perfusion. Values in healthy foals are currently unknown. Objective: Age, enteral feeding, and omeprazole administration would significantly alter gastric tonometry measurements in neonatal foals. Methods: Nine clinically normal foals were used to assess the effect of age and feeding, and 8 similar foals were used to assess the effect of omeprazole. Methods: At 1, 7, and 14 days of age, gastric intramucosal PCO2 (PgCO2) and arterial blood gas samples were obtained at baseline, immediately after feeding milk, an...
Giguère S, Slade JK, Sanchez LC.Despite a lack of data regarding their efficacy, both caffeine and doxapram have been recommended for treatment of hypercapnia in equine neonates with central nervous system damage. Objective: Caffeine and doxapram alleviate hypercapnia in foals with hypoxic-ischemic encephalopathy. Methods: Sixteen foals treated with either caffeine (n = 8) or doxapram (n = 8). Methods: Information on age, body temperature, heart rate, respiratory rate, arterial blood gas parameters, duration of therapy, and outcome was abstracted from each medical record. Results: Therapy with doxapram resulted in a signific...
Carluccio A, Panzani S, Tosi U, Riccaboni P, Contri A, Veronesi MC.This study was designed to establish the morphological features of the placenta of the Martina Franca jenny. Ten placentas were harvested at the time of foal delivery and examined both for gross and histological characteristics. The following factors were determined: the total weight and volume of the placenta and its components, the surface area of the allantochorion, umbilical cord length and site of insertion, and the diameter of the umbilical cord vessels and vascular pattern type. The weight of the placenta was similar to previously reported for ponies, and represented 12% of foal birth w...
Marenzoni ML, Passamonti F, Cappelli K, Veronesi F, Capomaccio S, Supplizi AV, Valente C, Autorino G, Coletti M.Fifteen unweaned thoroughbred foals, born on a stud farm to vaccinated mares, were clinically monitored during their first six months of life and repeatedly tested for equine herpesvirus type 1 (EHV-1) and equine herpesvirus type 4 (EHV-4). Nasopharyngeal swabs and blood samples were collected and screened respectively by PCR and seroneutralisation to detect the presence of the virus, explore its role as a possible cause of respiratory disease, and to assess the efficiency of the pcr for the diagnosis of this disease. The foals were divided into three groups on the basis of their clinical sign...
Torfason EG, Thorsteinsdóttir L, Torsteinsdóttir S, Svansson V.The horse population in Iceland is a special breed, isolated from other horses for at least 1000 years. This provides an exceptional opportunity to investigate old and new pathogens in an inbred herd with few infectious diseases. We have developed a high sensitivity semi-nested PCR to study equid gammaherpesviruses 2 and 5 (EHV-2 and 5) in Iceland. The first PCR is group specific, the second type-specific, targeting a 113bp sequence in the glyB gene. DNA isolated from white blood cells and 18 different organs was tested for the presence of EHV-2 and 5. This was done in adult horses and foals, ...
Carluccio A, De Amicis I, Panzani S, Tosi U, Faustini M, Veronesi MC.No knowledge regarding the peripartum changes in mammary secretions in the jenny are presently available in literature. In the mare, instead, several studies report the role of these changes as indicators of foetal readiness for birth and impending parturition. This experiment was designed to determine calcium, sodium, potassium concentrations, and the value of sodium/potassium ratio in mammary fluids during prepartum in the jenny. Samples were daily collected by hand milking, after mammary gland size increased noticeably, from 17 Martina Franca jennies. Prepartum mammary secretions were analy...
Patterson-Kane JC, Carrick JB, Axon JE, Wilkie I, Begg AP.The first outbreak of equine influenza virus (EIV) infection was confirmed in Australia in 2007. Some EIV-positive young foals died with bronchointerstitial pneumonia, an rare disease process in this age group that is often postulated to be caused by viral infection. Objective: The aim of this study was to describe post mortem lesions in EIV-infected foals. Methods: Post mortem examinations were conducted on 11 young foals (age 2-12 days) submitted to the Scone Veterinary Hospital, NSW over a 2-month period in 2007. The foals had presented with or developed fatal pneumonia, and were known or s...
Dickinson CE, Gould DH, Davidson AH, Avery PR, Legare ME, Hyatt DR, DebRoy C.A postpartum mare and foal were presented for evaluation of fever and lethargy in the mare. The mare was diagnosed with endometritis and initially responded well to treatment. On the second day of hospitalization, the mare developed renal insufficiency characterized by oliguria, azotemia, hemolysis, and thrombocytopenia. Concurrently, the foal developed rapidly progressive central nervous system signs culminating in refractory seizures. Both animals failed to respond to treatment and were euthanized. Thrombotic microangiopathy involving glomeruli was evident on microscopic examination of the m...
Cohen ND, Carter CN, Scott HM, Chaffin MK, Smith JL, Grimm MB, Kuskie KR, Takai S, Martens RJ.To determine whether soil concentrations of total or virulent Rhodococcus equi differed among breeding farms with and without foals with pneumonia caused by R equi. Methods: 37 farms in central Kentucky. Procedures-During January, March, and July 2006, the total concentration of R equi and concentration of virulent R equi were determined by use of quantitative bacteriologic culture and a colony immunoblot technique, respectively, in soil specimens obtained from farms. Differences in concentrations and proportion of virulent isolates within and among time points were compared among farms. Resul...
Armengou L, Monreal L, Tarancón I, Navarro M, Ríos J, Segura D.Septicemia is associated with a systemic inflammatory response, hemostatic activation, and disseminated intravascular coagulopathy (DIC). Objective: Increased plasma d-dimer concentration occurs in septic neonates and can reliably detect sepsis or DIC, and predict death in ill neonatal foals. Methods: 40 septic, 41 nonseptic hospitalized foals, and 22 healthy neonates. Methods: Prospective observational clinical study. Blood samples were collected on admission, at 24-48 hours after admission, and at the time of discharge or euthanasia. Plasma d-dimer concentration, clotting times, antithrombin...
Eberspächer E, Stanley SD, Rezende M, Steffey EP.To characterize the pharmacokinetics of fentanyl and the tolerance of foals to the drug following a single application of a commercially available transdermal system (TS). Methods: Prospective experimental study. Methods: Six (two male, four female) foals aged 4-8 days, weighing 56-74 kg. Methods: After placement of a jugular sampling catheter, one fentanyl TS (FTS) containing 10.2 mg fentanyl, released at 100 microg hour(-1), was applied for 72 hours. Blood samples were withdrawn over the course of 90 hours for fentanyl plasma analysis. Before and after the study, weight, complete blood count...
Ross J, Palmer JE, Wilkins PA.To review management of pregnant mares with body wall defects and assess the effect of various management strategies on the outcome of mares and their foals. Methods: Retrospective case series. Methods: 13 mares. Methods: Medical records of eligible mares were reviewed. Signalment, history, admitting complaint, clinical findings, parity, type of body wall defect, concurrent diagnoses, postpartum complications, outcome of fetus, outcome of mare, and type of clinical case management were recorded. Results: 8 mares received conservative management and 5 mares received interventional management. S...
Rubio-Martínez LM, Vázquez FJ, Romero A, Ormazábal JR.This paper reports on luxation of the elbow joint without concomitant fracture in a 1-month-old foal. Conservative treatment, with closed reduction and full-limb bandaging, including caudal and lateral splints, seemed successful initially, however, failed to provide enough stability and luxation recurred, and open reduction and surgical placement of prosthetic collateral ligaments was required. Luxation of the elbow joint should be considered when acute non-weight bearing forelimb lameness occurs associated with pain and swelling in the area of the elbow in young foals. Closed reduction failed...
Donabédian M, van Weeren PR, Perona G, Fleurance G, Robert C, Léger S, Bergero D, Lepage O, Martin-Rosset W.Diagnosis of osteochondrosis (OC) is based on clinical signs and radiography, but alternative methods for detection at an early stage would be useful. Objective: To determine in the juvenile horse the relationship between serum concentrations of a number of biomarkers that reflect changes in cartilage and bone turnover and age, feeding level, growth, and the occurrence of OC. Methods: Foals were assigned to a high (n = 20) or moderate (n = 19) feeding level group from birth to age 1 year. Bodyweight, withers height and cannon width were measured. Osteoarticular status was assessed radiographic...
Caron JP, Brakenhoff J.To report a technique for repair or prevention of inguinal hernia in horses using intracorporeal suture closure of the internal inguinal and vaginal rings. Methods: Case series. Methods: Foals (n=6) and geldings (n=2). Methods: After selection of a peri-umbilical telescope portal, instrument portals were made unilaterally or bilaterally, as needed. Herniated viscera was reduced, castration (foals) or spermatic cord remnant transection at the internal inguinal ring (adults) performed, and then simple interrupted intracorporeal sutures of synthetic absorbable suture material were used to close t...
Lawler JB, Hassel DM, Magnuson RJ, Hill AE, McCue PM, Traub-Dargatz JL.To determine the adsorptive capability of di-tri-octahedral smectite (DTOS) on Clostridium perfringens alpha, beta, and beta-2 exotoxins and equine colostral antibodies. Methods: 3 C perfringens exotoxins and 9 colostral samples. Methods: Alpha, beta, and beta-2 exotoxins were individually co-incubated with serial dilutions of DTOS or bismuth subsalicylate, and the amount of toxin remaining after incubation was determined via toxin-specific ELISAs. Colostral samples from healthy mares were individually co-incubated with serial dilutions of DTOS, and colostral IgG concentrations were determined...
Hart KA, Heusner GL, Norton NA, Barton MH.Hypothalamic-pituitary-adrenal (HPA) axis function is dynamic in the neonatal foal. The paired low dose/high dose cosyntropin (ACTH) stimulation test allows comprehensive HPA axis assessment, but has not been evaluated in neonatal foals. Objective: Foal age will significantly affect cortisol responses to a paired 10 and 100 microg dose cosyntropin stimulation test in healthy neonatal foals. Methods: Twenty healthy neonatal foals. Methods: HPA axis function was assessed in 12 foals at birth and at 12-24, 36-48 hours, and 5-7 days of age. At each age, basal cortisol and ACTH concentrations were ...
van Hoogmoed L, Yarbrough TB, Lecouteur RA, Hornof WJ.A 6 week old American Paint filly was admitted for evaluation of a dorsal thoracic mass suspected to be a meningocele. The diagnosis was confirmed by plain and contrast enhanced computed tomography. Surgical repair was performed by dissection of the base of the meningocele followed by ligation. No postoperative complications occurred. Contrast enhanced computed tomography was useful to confirm the diagnosis of meningocele and rule out a meningomyelocele.
Pusterla N, Mapes S, Gebhart C.The cell-mediated immune response to Lawsonia intracellularis, the agent of equine proliferative enteropathy (EPE), was investigated in vaccinated and naturally infected foals. Interferon (IFN)-γ gene expression was determined in peripheral blood mononuclear cells collected from vaccinated (n=6) and control foals (n=6) every 30 days for 180 days following first vaccine administration, and from clinically affected foals (n=16) within 7-10 days of diagnosing EPE. Seroconversion (immunoperoxidase monolayer assay titer ≥60) occurred in 5/6 vaccinated foals between 60 and 90 days following the f...
Cauchard J, Taouji S, Sevin C, Duquesne F, Bernabé M, Laugier C, Ballet JJ.Rhodococcus equi infection is considered the most common cause of pneumonia in foals less than 6 months of age. Immunization of foals and/or mares may become a procedure of choice for prevention. The present work documents the antibody response of neonate foals to R. equi virulence-associated protein (Vap) vaccine candidate peptides. A mixture of 4 R. equi (ATCC 33701) Vap peptides was selected based on their hydrophilicity and recognition by naturally acquired IgG antibodies from 13 adult horses and 33 neonate foals from France and Japan. They were combined with a water-based nanoparticular a...
Aleman M, Madigan JE, Williams DC, Holliday TA.Reports of the use of brainstem auditory evoked response (BAER) as a diagnostic modality in foals have been limited. Objective: To describe BAER findings and associated causes of hearing loss in foals. Methods: Study group 18 foals (15 neonatal, 3 nonneonatal), control group (5 neonatal foals). Methods: Retrospective. BAER records from the Clinical Neurophysiology Laboratory were reviewed from the years of 1982 to 2013. Peak latencies, amplitudes, and interpeak intervals were measured when visible. Clinical data were extracted from the medical records. Foals were grouped under disease categori...
Dubey JP, Porterfield ML.Multifocal areas of necrosis and infiltrations of mononuclear cells were seen in lung specimens of an equine fetus aborted 2 months before term. Extracellular and intracellular protozoa were seen in the alveolar tissue. Individual organisms were 4 microns by 2.5 microns, and cyst-like structures were 25 microns by 18 microns. Organisms did not stain with periodic acid-Schiff or by use of the immunoperoxidase and peroxidase-antiperoxidase method for Toxoplasma gondii. Twelve days after abortion, the mare had serum antibody titer of less than 1:10 against T gondii.
Robinson KA, Manning ST.This report describes a primiparous 8-year-old Morgan mare, which displayed premature lactation that began at approximately 240 d of gestation and lasted approximately 4 wk. The premature lactation resolved spontaneously, and the pregnancy was subsequently carried to full term with the delivery of a live foal and a mummified fetus. Lactation prématurée et rétention d’un fœtus momifié avec naissance vivante du jumeau chez une jument Morgan primipare. Ce rapport décrit une jument Morgan primipare âgée de 8 ans, qui a manifesté une lactation prématurée qui a commencé vers 240 jours ...
Pascoe JR, Meagher DM, Wheat JD.Uterine torsion was diagnosed in 26 mares of various breeds. The mean duration of gestation was 9.6 months. The most common clinical history was intermittent unresponsive colic of varying duration. Diagnosis of uterine torsion was confirmed by rectal palpation, and surgical correction was achieved in most cases by standing flank laparotomy and manual repositioning of the gravid uterus. Recumbent laparotomy was used only if the mare was intractable, the uterus was ruptured, or hysterotomy was indicated. Of 20 foals determined to be alive during surgery, 14 (70%) were subsequently born alive.
Hodgson DR.This article reviews what are considered the basic concepts of gas transport, blood gases, and acid-base physiology is most mammalian species. Techniques for the appropriate collection of blood samples for blood gas and acid-base determinations in the newborn foal are described. Guidelines for interpretation of these values in the normal foal and those animals undergoing respiratory and metabolic derangements are provided.
Wichtel JJ, Reinertson EL, Clark TL.Nonsurgical correction of uterine torsion was performed in 7 mares, and 6 foals were subsequently born alive. Uterine rupture necessitated euthanasia in 1 mare. Correction was achieved by rolling of the mares after general anesthesia had been induced. Previously, this technique was believed to be associated with a high prevalence of fetal and maternal mortality. Nonsurgical correction may be a satisfactory alternative to abdominal surgery in treating uterine torsion in mares.
McMullen RJ, Clode AB, Pandiri AK, Malarkey DE, Michau TM, Gilger BC.A case of epibulbar melanoma in a 6-month-old, gelded, chestnut Hanoverian foal is reported. The location and clinical appearance upon initial presentation led to the tentative diagnosis of staphyloma or a congenital mass of unknown origin. An attempt was made to surgically excise the mass under general anesthesia, but due to its infiltrative nature and intraoperative appearance, most, but not all was removed without compromising the integrity of the globe. Histopathological evaluation revealed a multinodular to packeted, poorly demarcated, unencapsulated, infiltrative exophytic melanocytic ne...
The Journal of hereditySeptember 1, 1984
Volume 75, Issue 5 413-414 doi: 10.1093/oxfordjournals.jhered.a109968
Sponenberg DP, Harper HT, Harper AL.A bay roan Brabant Belgian stallion (ERn/ ern) was bred to eight chestnut American Belgian mares (ern/ ern), producing 57 foals. Thirty foals were bay roan, 25 were chestnut, one was bay, and one was chestnut roan. The recombination rate was 0.035 +/- 0.024, indicating fairly close linkage between the roan (Rn) and extension (E) loci.
Mealey RH, Kappmeyer LS, Ueti MW, Wagner B, Knowles DP.Theileria equi immune plasma was infused into young horses (foals) with severe combined immunodeficiency. Although all foals became infected following intravenous challenge with homologous T. equi merozoite stabilate, delayed time to peak parasitemia occurred. Protective effects were associated with a predominance of passively transferred merozoite-specific IgG3.
Taouji S, Nomura I, Giguère S, Tomomitsu S, Kakuda T, Ganne V, Takaï S.Amino acid 65-78 of membrane protein VapA of the facultative intracellular Rhodococcus equi contained an immunodominant N-terminal B-cell epitope (N15Y peptide). Safety and immunogenecity of a synthetic peptide consisting of the amino acid 65-78 of VapA (peptide N15Y) were evaluated first in mice and in healthy adult horses. A single dose of a peptide-VapA vaccine induced and only in presence of adjuvant, specific IgG antibodies in sera of mice. After challenge with virulent R. equi 3 weeks after immunization, tissue clearance was more delayed in immunized mice than in control mice. An antibod...
McQueary CA, Worley DE, Catlin JE.Of 22 foals from 4 localities in southwestern Montana, 59% were found to be infected with Eimeria leuckarti. Oocysts collected from feces of 4 positive horses were sporulated and subsequently administered to a 5- to 6-month-old foal. The prepatent period was 31 days and the patent period was between 5 and 10 days.
Ellendorff F, Schams D.The neuroendocrine reflex theory of milk ejection was investigated in the horse under natural suckling conditions. To this end 12 lactating mares were provided with acute jugular catheters and with intramammary pressure (IMP) recording catheters. The foal had free access to the contralateral mammary complex. Intramammary pressure could thus be recorded while blood was drawn simultaneously for oxytocin analysis from the undisturbed animal. Suckling periods associated with a characteristic increase in IMP lasted significantly longer than unsuccessful nursing attempts. Elements of successful suck...
Giger R, Meier HP, Küpfer U.In a retrospective study the gestation lengths of two groups, each consisting of 193 "Freiberger" mares, were compared. The mares of the first group were bred by a donkey, those of the second group by a stallion of the "Freiberger" breed. On average, the gestation length of mares with "Freiberger" foals lasted 336.5 days, and that of mares with mule foals 343.1 days. The difference between both groups was significant (p < 0.001). The shortest and longest observed gestation length of mares with "Freiberger" foals was 307 and 361 days, and that of mares with mule foals 315 and 369 days, respecti...
Khan SA, Kuster DA, Hansen SR.Moxidectin is a macrolide endectocide available as a 2% equine oral gel in the US. This report presents clinical signs of moxidectin toxicosis and its treatment in equines as reported to the ASPCA Animal Poison Control Center (APCC) from January 1998 to December 2000. Nine cases of moxidectin overdose in equines occurred: 5 had signs of toxicosis such as coma, dyspnea, depression, ataxia, tremors, seizures, or weakness. The approximate dose of moxidectin at which these signs were observed ranged from 1.0 to 5.1 mg/kg. The 4 equines that ingested moxidectin between 0.9 mg/kg to 1.7 mg/kg did no...
Ainsworth DM, Beck KA, Boatwright CE, Snedden KA, Rebhun WC.The effect of prior Rhodococcus equi-induced pneumonia on pulmonary health was investigated in 5 horses (< 24 months old) using endoscopy, radiography, hematologic and bronchoalveolar lavage analyses, and pulmonary function testing. Rhodococcus equi-induced pneumonia had been diagnosed in principal horses when they were foals. Diagnosis was based on positive results of transtracheal aspiration and thoracic radiography at the time of initial clinical examination. Results of reevaluation of the respiratory system of these horses (R+) were compared with those of 5 age-matched healthy horses (R...
Omura CM, Drumond B, Rossi JL, Coelho CS, Gioso MA.Cephalometric studies are important to quantify abnormalities of jaw length and positioning. In this study, 4 to 7-month-old Quarter horse foals (n = 51) were examined to determine overjet (horizontal overlap) prevalence and measure the size of the physiological diastemata. Results were analyzed in relation to age, sex, and lineage. Another aim of this study was to develop a simple field technique for measuring incisor malocclusion and physiological diastemata dimensions that could be used to monitor the growth of the rostral components of maxilla, incisive bone, and mandible. The overall prev...
Owen JM.A condition frequently misnamed "contracted tendons" is described in unweaned foals. Various theories regarding its aetiology are examined. Overfeeding and lack of exercise are suggested as being the most likely causes, leading to excessive growth of the long bones. An effective method of treatment is described. "Contracted tendons" in yearlings are also discussed.
Johnson PJ, Mrad DR, Schwartz AJ, Kellam L.Outcome and complications associated with administration of moxidectin gel to 3 foals < 4 months old are described. Two foals became comatose but survived following supportive treatment. One foal died following loss of consciousness associated with moxidectin administration. Risk of moxidectin overdose exists, because horse owners often fail to read or comprehend the package insert instructions pertaining to use of the syringe-locking mechanism. In addition, moxidectin should not be administered to foals < 4 months old, because it is likely that treated foals will become comatose.
Johnson AK, Hinrichs K.There are few reports on the birth of foals resulting from equine adult somatic cell nuclear transfer (NT). On evaluation of reports of 28 live-born adult somatic-cell NT (clone) foals, 3 died within 2 weeks of birth of complications. Approximately 50 % of all reported cloned foals had complications, some requiring aggressive supportive care. The most common abnormalities reported were neonatal maladjustment syndrome, enlarged umbilical remnant, and angular deformity of the forelimbs, similar to problems described in cloned cattle. In contrast, large offspring syndrome and gross abnormalities ...
Hillidge CJ.Corynebacterium (Rhodococcus) equi is becoming increasingly significant as a cause of bronchopneumonia and lung abscessation in foals. The organism can survive within macrophages and may thus escape normal pulmonary defence mechanisms, particularly in immunocompromised animals. The disease has hitherto been associated with mortality rates as high as 80 per cent, partly as a result of inappropriate therapy. The selection of lipid-soluble antibiotics capable of intracellular penetration is critical for the successful treatment of C equi lung abscesses. A combination of two such antibiotics, eryt...
Haupt J, García-López JM, Chope K.Ventral midline hernia formation following abdominal surgery in horses is an uncommon complication; however, it can have serious consequences leading to increased morbidity and mortality. Currently, mesh hernioplasty is the treatment of choice for large ventral midline hernias in horses to allow potential return to normal function. Complications following mesh hernioplasty using polypropylene or polyester mesh in horses can be serious and similar to complications seen in human patients, including persistent incisional drainage, mesh infection, hernia recurrence, intra-abdominal adhesions, mesh...
Wilson KE, Davis JL, Crisman MV, Kvaternick V, Zarabadipour C, Cheramie H, Hodgson DR.The purpose of this study was to determine the pharmacokinetic profile of intravenous firocoxib in neonatal foals. Six healthy foals were administered 0.09 mg/kg firocoxib intravenously once a day for 7 days. Blood was collected for plasma firocoxib analysis using high-performance liquid chromatography with fluorescence detection at times 0 (day 1 of study only) and 0.08, 0.25, 1, 2, 4, 6, 8, 16 and 24 hr on dose numbers 1, 5 and 7. Blood was also collected immediately prior to doses 3, 4, 5 and 7. Final samples were collected at 36, 48, 72 and 96 hr following the final dose. Noncompartmen...
Dwyer RM.Rotavirus poses a challenge each foaling season to farm managers and veterinarians in intensive horse breeding areas throughout the world. By understanding the epidemiology of the disease as well as characteristics of the virus, veterinarians can make sound recommendations on prevention and control of outbreaks. Even when effective prophylactic products are developed, farm management practices, including quarantine, disinfection, and hygiene, will always need to be in force to prevent any contagious disease outbreak.
Juzwiak JS, Slone DE, Santschi EM, Moll HD.The case records of 19 mares undergoing caudal ventral midline celiotomy for cesarean section were reviewed. Surgical exposure to the uterus was good, and the incisions healed by first intention in surviving mares. Seventeen mares (89%) survived to time of hospital discharge. Six foals (32%) were delivered alive, of which three were euthanatized because of severe deformity (1 died on day 6 and 2 survived to time of discharge). The most frequent postoperative complications were abdominal pain (13 mares), anemia (10 mares), and retained placenta (6 mares). Sixteen mares were bred during at least...
Takai S, Yoda A, Sasaki Y, Kakuda T, Suzuki Y, Oikawa M.Tracheal washing fluid was collected from 170 foals at 28 and 35 d old from February to July in a foaling season on horse-breeding farms with sporadic rhodococcosis in Japan and was investigated by quantitative culture. The history of the 170 foals followed up for the next few months. The proportion of R. equi-positive foals at 28 and 35 d old was significantly increased according to the birth month. Furthermore, the mean number of R. equi in the tracheal washing fluid of each month group increased according to their birth month with the rise in outside temperature. During the follow-up observ...
Kowalczyk DF, Gunson DE, Shoop CR, Ramberg CF.To study the effects of environmental exposure to zinc and cadmium in immature foals, five pregnant ponies were raised within 2.9 km of the New Jersey Zinc Smelter in Palmerton, Pennsylvania. The mares and their foals were kept outdoors on timothy hay and orchard grass. The foals were examined daily for signs of illness and blood samples were taken monthly for estimation of serum zinc, copper, and ceruloplasmin levels. The foals were sacrificed at 2.5, 4.5, 8.5, 13.5, and 18.5 months of age. Necropsy revealed generalized osteochondrosis in joints of the limbs and cervical vertebrae, lymphoid h...
Ronéus B.When blood selenium concentrations and glutathione peroxidase activity was measured in 30 standardbred horses a significant correlation was found (r = 0.97). A comparison between blood GSH-px activity in clinically healthy foals, foals affected by muscular dystrophy (MD) and their respective mares was also done. There was no difference in GSH-px activity between the healthy foals and the MD foals or between the corresponding mares.