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Background Real-time, quantitative PCR (qPCR) methods for detecting Rhodococcus equi in feces have been developed as a noninvasive, rapid diagnostic test for R. equi pneumonia, but have not been evaluated in a large population of foals. Objective The objective of this study was to evaluate the clinical utility of fecal PCR as a diagnostic test for R. equi pneumonia in foals using receiver operating characteristic (ROC) methods. Animals 186 foals born in 2011 at an R. equi-endemic ranch in Texas. Methods Fecal samples were collected at the time of onset of clinical signs for pneumonic foals (n = 31). Foals with pneumonia were matched by age and birth date to healthy (n = 31) and subclinical (n = 124) control foals; fecal samples were collected from these controls. DNA was extracted from feces using commercial kits and concentration of virulent R. equi in feces was determined by qPCR. Results Concentration of R. equi in feces differed significantly (P

Rhodococcus equi is a significant cause of pneumonia, resulting in disease and sometimes death of foals. It is believed that infection occurs by inhalation of dust contaminated with virulent Re qui. Although association between the airborne concentration of virulent R equi and the incidence of foal pneumonia at breeding farms has been documented, studies at the level of individual foals have not been reported. Thus, the objective of this study was to determine whether the magnitude of airborne virulent R equi was signifi- cantly associated with risk of Re quipneumonia for individual foals. The concentration of virulent R equi was significantly (P

Summary This report describes a 4-month-old Quarter Horse filly with an ectopic ureter. The filly presented with signs of urinary incontinence, which had been present since birth. Computed tomography (CT) examination and cystoscopy confirmed a diagnosis of a unilateral ectopic ureter. A nephrectomy of the left kidney was performed and renal function was closely monitored post operatively. The filly was treated for abdominal chylous effusion as a post operative complication. The filly survived to discharge from the hospital, and maintained normal urinary function at 12 months post operatively.

Summary The case reported here describes a rare presentation of necrotising, emphysematous oesophagitis and gastritis in a horse presenting for signs of anorexia, dysphagia and ptyalism. Radiography of the retropharyngeal region revealed intramural gas within the cranial oesophagus. Further diagnostic evaluation supported an ante mortem diagnosis of emphysematous oesophagitis with concurrent septic pleuritis and peritonitis. Post mortem findings confirmed an emphysematous, necrotising oesophagitis and gastritis with a Clostridium sp. transmural infection. To our knowledge, this case describes the first recorded ante mortem diagnosis of emphysematous oesophagitis with concurrent gastritis in the horse.

Summary The immunotherapeutic efficacy of specific immune plasma was evaluated in pony foals infected experimentally with Rhodococcus equi. Viable R. equi were aerosolised into the right caudodorsal lung of 10 foals at seven days of age. Immune plasma, produced by repeated parenteral administration of viable R. equi to an adult donor gelding, was harvested and frozen. Group 1 (4 foals) and Group 2 (6 foals) foals received lactated Ringer's solution and immune plasma, respectively, at seven and nine days post infection. Clinical signs, haematological alterations, immune responses and thoracic radiographs were monitored throughout the study. All foals were destroyed and complete post mortem examinations were performed. All foals developed pneumonia as evidenced by clinical and radiographic alterations. Immune plasma had no significant effect on survival rate, length of survival, temperature response or peripheral blood concentrations of leucocytes, neutrophils or fibrinogen. Enzyme-linked immunosorbent assay values for R. equi-specific antibody and serum concentrations of IgG were significantly greater in Group 2 foals following treatment with immune plasma. Post mortem examination of three Group 1 and four Group 2 foals, destroyed because of terminal disease, revealed severe pyogranulomatous pneumonia. The two surviving Group 2 foals were free of gross pulmonary lesions and had minimal microscopic scar formation three months post infection; whereas the one surviving Group 1 foal had a large, encapsulated, caseonecrotic pulmonary mass three months post infection. This study demonstrates that the parenteral administration of R. equi immune plasma to foals seven days after experimental infection with R. equi does not alleviate the clinical signs nor alter the course of disease.

Summary Reasons for performing study: Prognosis of Rhodococcus equi pneumonia can be challenging because the course of the disease is often insidious and overt clinical signs are subtle. Early diagnosis is considered desirable because it may offer the chance of more successful implementation of treatment and, thereby, improved outcome. Serological tests have previously failed to be accurate for early detection or diagnosis. Measurement of serum amyloid A (SAA) prior to and at the time of clinical signs was therefore chosen in order to assess its potential clinical use. Objective: To determine whether SAA concentrations differentiate foals affected with R. equi pneumonia from unaffected foals, either prior to the onset of disease or at the time of onset of clinical signs. Hypothesis: SAA concentrations are significantly higher among foals that develop R. equi pneumonia than in foals from the same environment that remain clinically unaffected. Methods: Serum samples were obtained from 212 foals 7–14 days and 196 foals 21–28 days post partum, and from affected foals and age-matched controls at the time of onset of signs of pneumonia. SAA concentration was determined for each sample. Results: There were no significant differences between SAA concentrations of foals with R. equi and clinically unaffected foals during the 2 periods of examination or at the time of onset of clinical signs of R. equi pneumonia. Conclusions: Concentrations of SAA are variable among foals with R. equi pneumonia and cannot be used reliably either as an ancillary diagnostic tool or to screen for early detection of disease during the first month post partum. Potential relevance: Bimonthly monitoring concentration of SAA is not useful as a screening test for early detection of R. equi pneumonia and does not facilitate diagnosis of this disease when used according to the protocol of this study.

Summary Streptococcus equi ssp. equi infection in the horse, or strangles, commonly results in abscessation of the submandibular, submaxillary or retropharyngeal lymph nodes. Although this classical presentation of strangles is associated with a low mortality rate, complications and sequlae may worsen the prognosis and increase mortality rates. This article reviews sequelae and complictions of S. equi ssp. equi infection in the horse, including guttural pouch empyema, bastard strangles and immune mediated diseases such as purpura haemorrhagica, myopathies and myocarditis.

Summary The case reported here represents an atypical presentation of bastard strangles in an 18-year-old Arab mare. The horse initially presented for progressive neck pain characterised by reluctance to lateral and ventroflexion of the neck. Subsequent diagnostics revealed a subscapular abscess and aspirates of the mass cultured positive for Streptococcus equi ssp. equi. Surgical drainage and debridement of the abscess was performed under general anaesthesia. Six months post surgery, the mare had made a complete recovery.

Summary The case of a horse with a subchondral bone cyst in the lateral slope of the intermediate humeral tubercle is presented. Diagnosis was complicated by the unusual location and subsequent challenge in imaging the cyst. Endoscopic debridement resulted in a good outcome.

Background Current screening tests for Rhodococcus equi pneumonia in foals lack adequate accuracy for clinical use. Real-time, quantitative PCR (qPCR) for virulent R. equi in feces has not been systematically evaluated as a screening test. Objective The objective of this study was to evaluate the accuracy of qPCR for vapA in serially collected fecal samples as a screening test for R. equi pneumonia in foals. Animals One hundred and twenty-five foals born in 2011 at a ranch in Texas. Methods Fecal samples were collected concurrently with thoracic ultrasonography (TUS) screening examinations at ages 3, 5, and 7 weeks. Affected (pneumonic) foals (n = 25) were matched by age and date-of-birth to unaffected (n = 25) and subclinical (ie, having thoracic TUS lesions but no clinical signs of pneumonia) foals (n = 75). DNA was extracted from feces using commercial kits and concentration of virulent R. equi in feces was determined by qPCR. Results Subsequently affected foals had significantly greater concentrations of vapA in feces than foals that did not develop pneumonia (unaffected and subclinical foals) at 5 and 7 weeks of age. Accuracy of fecal qPCR, however, was poor as a screening test to differentiate foals that would develop clinical signs of pneumonia from those that would remain free of clinical signs (including foals with subclinical pulmonary lesions attributed to R. equi) using receiver operating characteristic (ROC) methods. Conclusions and Clinical Importance In the population studied, serial qPCR on feces lacked adequate accuracy as a screening test for clinical R. equi foal pneumonia.

Objectives—To compare limb-load distribution between horses with and without acute or chronic laminitis. Animals—10 horses with carbohydrate-induced acute laminitis, 20 horses with naturally occurring chronic laminitis, and 20 horses without foot abnormalities (controls). Procedures—Limb-load distribution was determined, using a custom-designed system that allowed simultaneous quantification of the mean percentage of body weight voluntarily placed on each limb (ie, mean limb load) and the SD of the mean load over a 5- minute period (ie, load distribution profile [LDP]). Load distribution profile was used as an index of frequency of load redistribution. Results—Mean loads on fore- and hind limbs in control horses were 58 and 42%, respectively, and loads were equally and normally distributed between left and right limbs. In addition, forelimb LDP was greater, compared with hind limbs, and was affected by head and neck movement. In comparison, limb-load distribution in horses with chronic laminitis was characterized by an increase in the preferential loading of a forelimb, a decrease in total forelimb load, and an increase in LDP that was correlated with severity of lameness. In horses with carbohydrate-induced acute laminitis, mean limb loads after onset of lameness were not different from those prior to lameness; however, LDP was significantly decreased after onset of lameness. Conclusion and Clinical Relevance—Quantification of limb-load distribution may be an applicable screening method for detecting acute laminitis, grading severity of lameness, and monitoring rehabilitation of horses with chronic laminitis. (Am J Vet Res 2001; 62:1393–1398)

Objective—To determine whether isolation and virulence of Rhodococcus equi from soil and infected foals are associated with clinical disease. Design—Cross-sectional and case-control study. Sample Population—R equi isolates from 50 foals with pneumonia and soil samples from 33 farms with and 33 farms without a history of R equi infection (affected and control, respectively). Procedure—R equi was selectively isolated from soil samples. Soil and clinical isolates were evaluated for virulence-associated protein antigen plasmids (VapAP) and resistance to the β-lactam antibiotics penicillin G and cephalothin. Microbiologic cultures and VapA-P assays were performed at 2 independent laboratories. Results—VapA-P was detected in 49 of 50 (98%) clinical isolates; there was complete agreement between laboratories. Rhodococcus equi was isolated from soil on 28 of 33 (84.8%) affected farms and 24 of 33 (72.7%) control farms, but there was poor agreement between laboratories. Virulence-associated protein antigen plasmids were detected on 14 of 66 (21.2%) farms by either laboratory, but results agreed for only 1 of the 14 VapA-P-positive farms. We did not detect significant associations between disease status and isolation of R equi from soil, detection of VapA-P in soil isolates, or resistance of soil isolates to β-lactam antibiotics. No association between β-lactam antibiotic resistance and presence of VapA-P was detected. Conclusions and Clinical Relevance—On the basis of soil microbiologic culture and VapA-P assay results, it is not possible to determine whether foals on a given farm are at increased risk of developing disease caused by R equi. (J Am Vet Med Assoc 2000;217:220–225)

Summary A commercially available pulse oximeter was evaluated in anaesthetised foals to determine its accuracy for estimating arterial haemoglobin saturation (SaO2). Five different transducer/transducer attachment site (TIAS) combinations were evaluated; 1–3) a fingertip transmission transducer attached to the foal's ear, lip and tongue, 4) an adhesive transmission transducer positioned on the foal's ear and 5) a forehead reflectance transducer placed on the ventral aspect of the foal's tail-base. Eight normal, Quarter Horse foals (age 5–10 days) were studied while under general anaesthesia. Alterations in arterial carbon dioxide tension (PaCO2) were produced by changing the level of ventilation. At each level of ventilation, alterations of arterial haemoglobin saturation (SaO2) were produced by varying the inspired fraction of oxygen (FIO2). At each level of ventilation and each level of FIO2, arterial blood samples were obtained for blood gas analysis while pulse oximeter readings were recorded simultaneously for each TTAS combination. Arterial blood oxygen saturation (SaO2) was calculated from arterial blood gas values and the equine blood oxygen dissociation curve. Pulse oximeter readings from each TTAS combination were compared with SaO2 values with linear regression analyses. Bias and precision values were determined and the sensitivity and specificity of each TTAS combination for detecting desaturation (SaO2

Implanted medical devices rely on many different and complex joints between dissimilar materials. Adhesives provide one solution for creating such joints. While long-term implants have the advantage of being in a constant-temperature environment, these adhesive joints need to meet the additional challenges of complex loading conditions and ever increasing device-lifetime requirements. The principles of joint design, namely avoiding peel and cleavage-loading conditions, must be scaled down to meet the ever decreasing device sizes. Because the long-term reliability of an adhesive joint under wet fatigue loading conditions generally scales with the adhesion strength between the adhesive and the substrate, surface modification strategies are often employed to improve joint strengths. Any primers or adhesives must meet the biocompatibility requirements which in large part address leachable toxicity. As a result, the use of many fast- or light-cure adhesives is very limited in long-term implant applications. As such, the industry is constrained to relatively few adhesive chemistry options. In this chapter, we review joint design strategies, present methods to test the adhesive strength, discuss methods for improving adhesion strength and provide lessons learned from examples of joints.

Background Representatives from a herd of horses with acute onset of neurologic signs after administration of ivermectin presented for evaluation and treatment. Objectives Describe clinical signs of horses intoxicated by ingestion of Solanum sp. and administered ivermectin. Animals Six of 11 affected unrelated horses presented for evaluation and treatment. The remaining 5 affected horses were treated at the farm. Four additional horses, housed separately, were unaffected. Methods Case series is presented. Serum ivermectin concentrations were evaluated in the 6 hospitalized horses. The remnants of the tubes of ivermectin paste were analyzed for ivermectin concentration. The hay fed to the affected horses was analyzed for the presence of toxic plants. Results Serum ivermectin concentrations were higher than expected, given the dosage of ivermectin administered. The ivermectin concentration remaining in the administration tubes did not exceed specifications. The hay was heavily contaminated by 2 Solanum species. All horses returned to normal neurologic function with supportive care. Conclusions and Clinical Importance Horses might exhibit signs of ivermectin toxicity after appropriate dosing of the drug if they concurrently consume toxic plants of the Solanum family.

The schistosome Heterobilharzia americana infects dogs, raccoons, and other mammals in the southeastern United States. Migration of eggs into the liver results in parasitic granulomas with varying degrees of fibrosis and inflammation. Recently, hepatic parasitic granulomas in horses were shown to be caused by H. americana infection. In the present study, samples of liver from 11 of 12 horses with hepatic granulomas identified at necropsy ( n = 11) or surgical biopsy ( n = 1) were used for DNA extraction, polymerase chain reaction amplification and sequencing using primers specific for a portion of the H. americana small subunit ribosomal RNA gene. A polymerase chain reaction amplicon of the correct size was produced from the extracted DNA in 8 of the 11 horses. Amplicons from 5 of the 8 positive horses were sequenced and had 100% identity with H. americana. In all but 2 of the 12 horses, Heterobilharzia was not responsible for the primary clinical disease, and the hepatic granulomas were considered an incidental finding.

A 1.5-year-old Quarter Horse gelding with a history of chronic nasal discharge and leukocytosis presented with signs of increased lethargy and muscular pain. The horse quickly became recumbent and unable to rise and was euthanized due to a poor prognosis. At necropsy, severe bilateral guttural pouch empyema was observed, as well as numerous well-demarcated areas of pallor within the skeletal muscles of all major muscle groups. Polymerase chain reaction testing of the guttural pouch exudate confirmed an infection with Streptococcus equi subsp. equi, and an S. equi-associated immune-mediated rhabdomyolysis was initially considered to be the most likely diagnosis. This report briefly discusses the various etiologies that should be considered in cases of equine myopathy, and it demonstrates the complexity of these poorly understood muscular disorders.

Gallium is a trivalent semi-metal with anti-microbial effects because of its incorporation into crucial iron-dependent reproductive enzyme systems. Gallium maltolate (GaM) provides significant gallium bioavailability to people and mice following oral administration and to neonatal foals following intragastric administration. To study the prophylactic and therapeutic effects of GaM against Rhodococcus equi pneumonia in foals, we developed a methylcellulose formulation of GaM (GaM-MCF) for oral administration to neonatal foals. Normal neonatal foals were studied. Six foals received 20 mg/kg and another six foals received 40 mg/kg of GaM-MCF orally. Serial serum samples were collected and serum gallium concentrations were determined using inductively coupled plasma mass spectroscopy. Gallium was rapidly absorbed (T(max) of 4 h), and a mean C(max) of 0.90 or 1.8 microg/mL was achieved in foals receiving 20 or 40 mg/kg respectively. Marked variability existed in C(max) among foals: only half of the foals receiving 20 mg/kg attained serum concentrations of >0.7 microg/mL, a level suggested to be therapeutic against R. equi by previous studies. Mean elimination half-life was 32.8 or 32.4 h for foals receiving 20 or 40 mg/kg respectively. The results of this study suggest that at least 30 mg/kg orally every 24 h should be considered in future pharmacodynamic and efficacy studies.

Gallium maltolate (GaM) has been proposed as a new agent for the prevention and control of foal pneumonia caused by the intracellular bacterium Rhodococcus equi. This proposal is based on the observed antimicrobial effectiveness of GaM on R. equi (Harrington. et al., 2006; Martens et al., 2007a), and the known pharmacokinetics of GaM in neonatal foals (Martens et al., 2007b). The use of GaM represents a novel approach to combating infections: the exploitation of a major stress already imposed on an organism by the host s environment. Adequate availability of ferric iron (Fe) is essential for the growth of most pathogenic bacteria, including R. equi (Jordan et al., 2003), which rely on Fe-dependent enzyme systems (Bullen et al., 2005). A major host innate antimicrobial defense mechanism is the sequestration of available Fe by host plasma proteins, primarily transferrin and lactoferrin. Rhodococcus equi, however, can acquire and utilize transferrinand lactoferrin-bound iron, thereby circumventing this defense mechanism (Jordan et al., 2003). Gallium, a trivalent semi-metal that shares many chemical similarities with Fe and functions as a ferric iron mimic, has been used to control various microorganisms by exploiting their iron dependency (Bernstein, 1998; Oyebode et al., 2000; Harrington et al., 2006; Kaneko et al., 2007). Gallium competes with Fe for uptake by bacteria and is incorporated into crucial Fe-dependent enzyme systems. Trivalent gallium, unlike Fe, is unable to undergo redox-cycling, which leads to inactivation of some Fe-dependent enzymes (particularly ribonucleotide reductase), causing bacterial stasis and death (Bernstein, 1998). Gallium salts (e.g., gallium chloride, gallium nitrate) are not well absorbed orally (Bernstein, 1998). In the only reports of an herbivore species or a neonate in which Ga administration has been assessed, neonatal calves treated with oral gallium chloride developed severe intestinal lesions, alterations in enteric microflora, and diarrhea (Fettman et al., 1987a,b). A citrate-chelated gallium nitrate solution for injection (Ganite , Genta Inc., Berkeley Heights, NJ, USA), which is FDA-approved for treatment of human cancer-related hypercalcemia, is associated with renal toxicity when administered as an IV bolus (Bernstein, 2005). Gallium maltolate, a coordination complex of Ga and maltol, developed by a co-author (LRB), has high oral bioavailability in humans and a variety of other species (Bernstein et al., 2000), and attains potentially therapeutic serum concentrations in neonatal foals (Martens et al., 2007b). Adverse responses to enteral GaM have not been reported in humans or laboratory animal species, but safety studies have not been reported for either neonates or horses. During the neonatal period (first days-to-weeks of life) most mammals have immature or inefficient organ systems and are undergoing a variety of physiologic adaptations that can impact their pharmacologic and toxicologic responsiveness (Koterba, 1990). This report assesses the safety of GaM in neonatal foals by comparing clinical and clinicopathologic parameters of foals that received five daily doses of enteral GaM or distilled water. The authors believe that this is the first report on the safety of GaM therapy in neonates of any species. Rhodococcus equi is a facultative intracellular bacterium that causes severe bronchopneumonia in foals and immunocompromised people (Giguere & Prescott, 1997). Most foals appear to become infected within the first few days of life (Horowitz et al., 2001), when they may have immature or ineffective immune responses (Boyd et al., 2003; Chaffin et al., 2004). Because the J. vet. Pharmacol. Therap. 33, 208–212, doi: 10.1111/j.1365-2885.2009.01121.x. SHORT COMMUNICATION

An intrathoracic esophageal pulsion diverticulum causing repeated episodes of esophageal obstruction in a Morgan weanling colt was diagnosed by endoscopy, positive contrast radiography, and pleuroscopy. Surgical excision of the diverticulum alleviated clinical signs, and the horse was able to resume a normal diet by day 6. After 9 months the colt remains asymptomatic.

This report involves 6 cases in which medical records and post mortem findings were reviewed leading to the diagnosis of massive pulmonary thromboembolism (MPTE). All horses were mature and MPTE has not been recognised previously as a sequel to generalised systemic illness in mature horses. The clinical data and pathological findings of the cases are reported and the authors conclude that MPTE is an uncommon but important complication of medical and surgical disorders in mature horses. In 3 of the cases, the condition was nonfatal suggesting that some horses having developed PTE survive and the condition may not be recognised in such cases. The incidence of the condition might be higher than supposed.

To identify features of guttural pouch (auditory tube diverticulum) empyema in horses and compare findings of uncomplicated guttural pouch empyema with guttural pouch empyema complicated by chondroids.Retrospective study.91 horses with guttural pouch empyema.Medical records of horses with guttural pouch empyema were reviewed.The most common owner complaint and abnormal finding was persistent nasal discharge. Chondroids were detected in 21% (19/91) of affected horses. Streptococcus equi was isolated from the guttural pouch in 14 of 44 horses; for Streptococcus spp, in vitro resistance to sulfadimethoxine and trimethoprim-sulfamethoxazole was detected. Retropharyngeal swelling and pharyngeal narrowing were significantly more prevalent in horses with chondroids, compared with horses with uncomplicated empyema. Ninety-three percent of affected horses were discharged from the hospital; at time of discharge, 66% had complete resolution of disease, 19% had improvement without resolution, and 15% did not have improvement.Horses with persistent nasal discharge should be examined endoscopically for guttural pouch empyema. Treatment with lavage offers a good prognosis for resolution of uncomplicated guttural pouch empyema. Aggressive treatment with lavage and endoscopic snare removal of chondroids offers a good prognosis and may make surgical intervention unnecessary.

Foals are uniquely susceptible to a wide variety of opportunistic infections normally associated with immunodeficiencies. Little is understood about the immune system of foals during the neonatal period. An apparent age-related susceptibility predisposes neonatal foals to infectious diseases and hinders therapeutic and preventative interventions for these diseases. Cytokine expression is correlated with the type of immune response as well as the severity of a disease. In this study, we measured foal peripheral blood mononuclear cell (PBMC)-specific mRNA cytokine expression from 72 foals from three different farms during the first 4 weeks of life. Interleukin-1alpha (IL-1alpha), IL-1beta, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p35, IL-12p40, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and transforming growth factor-beta1 (TGF-beta1) were cloned and transcribed in vitro to generate antisense probes for ribonuclease protection assays. Using linear mixed-effect models, we determined that IFN-gamma, TGF-beta1, and IL-1alpha increased significantly (P0.05) with age.

To determine whether administration of commercially available Escherichia coli antiserum to neonatal foals would affect serum IgG concentration or morbidity and mortality rates during the first 60 days of life.Randomized controlled trial.271 neonatal foals on 4 well-managed farms.Foals were randomly assigned to a treatment or control group. All foals were allowed to suckle colostrum normally. In addition, treatment-group foals were given E coli antiserum (10 micromilligrams) orally between 0 and 8 hours after birth. Serum samples were obtained between 18 and 36 hours after birth, and serum IgG concentration was determined. Foals were monitored for the first 60 days after birth, and causes of disease or death were recorded.Groups did not differ significantly in regard to breed, sex, month of birth, season of birth, age of dams, parity of dams, duration of gestation, or specific gravity of colostrum before suckling. In addition, groups did not differ significantly in regard to mean serum IgG concentration, prevalence of complete or partial failure of passive transfer of immunity, frequency or causes of disease, or frequency of death from infectious causes.In this group of foals on well-managed farms, administration of E coli antiserum did not alter serum IgG concentrations or morbidity and mortality rates during the first 60 days of life.

In order to identify variables obtained at admission that could be used to predict survival in septicemic foals, medical records of 65 foals diagnosed with septicemia were reviewed. Initially, variables were analyzed independently (univariate analysis) for association with survival. Of the physical examination and historical data examined using univariate analysis, the ability to stand at admission, respiratory rateor = 60 breaths per minute (bpm), and normal-appearing mucous membranes were significantly associated with survival. Foals with history of induced parturition were significantly less likely to survive. The following hematologic and serum biochemical variables determined at admission were significantly associated with survival: white blood cell countor = 6,000 cells/microL, neutrophil count4,000 cells/microL, serum albumin concentration2.2 g/dL, serum glucose concentration120 mg/dL, blood pHor = 7.35, and positive base excess. The administration of plasma at admission was significantly associated with survival. Stepwise multiple logistic regression analysis was performed to evaluate the association between survival and variables identified as significantly associated with survival in bivariate analysis. The final multivariate model selected included the variables standing, duration of clinical signs (24-hour intervals) prior to admission, respiratory rateor = 60 bpm, neutropenia (or = 4,000 cells/ microL), and neonatal age category. The probability of survival was significantly increased for foals that were standing, had a respiratory rateor = 60 bpm, and that had a neutrophil count4,000 cells/microL at admission. Probability of survival was significantly decreased for foals that had a longer duration of clinical signs prior to admission. For each 24 hours of duration, the estimated risk of death was increased by 5.8-fold.

To evaluate the effect of peritoneal lavage on pharmacokinetics of gentamicin sulfate in healthy horses after experimental celiotomy.13 clinically normal horses.Horses were randomly assigned to control or experimental groups. All horses received gentamicin (6.6 mg/kg of body weight, IV, q 24 h) before surgery, underwent experimental abdominal surgery, and had abdominal drains placed percutaneously. Horses of the experimental group received postoperative peritoneal lavage; horses of the control group did not receive peritoneal lavage. The day after surgery, 24 hours after the preoperative dose of gentamicin, a second dose of gentamicin was administered. Three and 15 hours after this second dose of gentamicin, horses of the experimental group received peritoneal lavage. Venous blood was obtained, for determination of concentration of gentamicin, immediately before and at specified intervals during the 24-hour period after the second dose of gentamicin.There were no differences in any of the pharmacokinetic values of gentamicin between horses of the control and experimental groups.Peritoneal lavage had no effect on pharmacokinetics of gentamicin in healthy horses after abdominal surgery, in which localized nonseptic peritonitis was induced.Peritoneal lavage in horses with localized nonseptic peritonitis or for the prevention of intra-abdominal adhesions should not necessitate alteration of the dosage of gentamicin to maintain predictable serum concentrations.

To compare effects of 3 oxytocin-based induction techniques on fetal and neonatal foals.Prospective randomized controlled trial.16 pregnant mares.Parturition was induced in mares by use of 3 treatments: group 1, 75 U of oxytocin, IM; group 2, 15 U of oxytocin, IM, q 15 minutes, for a maximum of 75 U; group 3, 75 U of oxytocin in 1 L of 0.9% NaCl solution IV (1 U/min), for a maximum of 75 U. Blood gas values and indices of vitality were measured in foals, and variables describing parturition were measured in mares.Group-3 mares had a shorter interval from administration of oxytocin to rupture of the chorioallantois (OTCA) than group-2 mares. More foals were abnormal when the interval from oxytocin administration to delivery of the foal (OTDE) wasor = 60 minutes. Arterial blood gas values, measurements of vitality, and plasma cortisol concentrations did not differ among foals in various treatment groups. Increased interval for OTCA and OTDE resulted in higher neonatal PaCO2, and a longer interval for OTCA resulted in lower arterial pH. Time required for birth was shorter in mares with a dilated cervix. More abnormal foals than normal foals were delivered after premature placental separation or dystocia. Abnormal foals took longer to stand and suckle than normal foals. Interval from delivery to suckling was positively correlated with OTCA, OTDE, and PaCO2.Method of oxytocin-induced parturition did not impact neonatal outcome. Interval from induction until parturition, degree of cervical dilatation, and intrapartum complications influenced induction success.

Permanent tracheal stomas were created in seven sedated, standing horses with severe upper airway obstruction. After local anesthesia, a 3-cm by 6-cm rectangle of skin was removed from the ventral surface of the neck, 3 cm distal to the cricoid cartilage. The sternothyrohyoideus muscles were clamped proximally and distally, then transected to expose the tracheal rings. The ventral third of four tracheal rings was dissected from the tracheal mucosa that was then incised in a double "Y." Two layers of suture were used to achieve mucocutaneous closure. Stomas healed without serious complications; two mares subsequently foaled, and three horses were used for riding.

A 4-month-old male Quarter Horse was referred for evaluation of urinary incontinence. Physical examination revealed clinical signs consistent with cauda equina syndrome. Radiography revealed diskospondylitis of S2 through S4. Infected bone was surgically curretted, and drainage was established for an associated paravertebral abscess. Rhodococcus equi was isolated from specimens of bone and from fluid samples obtained from the paravertebral abscess. Bethanechol was administered to stimulate urination. Erythromycin and rifampin were administered for 120 days. The foal's neurologic dysfunction resolved completely. Two years after discharge, the horse remained neurologically normal and did not have apparent effects as a result of its previous disorder.

The bicipital tendons and bursae of 25 healthy adult Quarter Horses were ultrasonographically examined. Cross-sectional images of the right and left bicipital tendons were obtained from each horse, using a 7.5-MHz transducer held in the frontal plane at the point of the shoulder. The bicipital tendon at the point of the shoulder appeared as a bilobate structure overlying the echogenic surface of the humerus. Median distance from the skin surface to the cranial surface of the tendon on the medial sagittal plane of the tendon was 23 mm (range, 16.5 to 30 mm); median distance on the lateral sagittal plane was 14 mm (range, 8.5 to 19 mm). Median distance from the skin surface to the tendon on the midsagittal plane of the tendon was 17 mm (range, 10.5 to 22 mm). Median cranial-to-caudal widths of the lateral and medial lobes of the tendon at their greatest dimensions were 20.5 mm (range, 18 to 27.5 mm) and 16 mm (range, 13 to 20.5 mm), respectively. The median cranial-to-caudal width of the central (midsagittal) portion of the tendon was 10 mm (range, 7 to 13.5 mm). The bicipital bursa wasor = 3 mm wide at all locations at which it was measured. Ultrasonographic imaging was easily performed and allowed evaluation of the bicipital tendon, bursa, and surface of the underlying humerus.

isolated 3 strains with different colonies sizes on the blood agar plate, UBA8Ch (0.5mm), UBA8Md (2mm) andUBA8Gd (4 mm). Expression of capsule was observed by negative staining with India ink solution and with electron microscopywith fosfotungstic acid.Diskdiffusion testwereusedas recommended by Clinical and Laboratory Standards Institute (CLSI). The antibiotic tested were: erithromycin (ERY), penicillin (PEN), ciprofloxacine (CIP), enrofloxacin (ENR), tetracycline (TET) trimethoprim-sulfamethoxazole (TMS), cefotaxime (CTX) and florfenicol (FFC). Results were categorized by using the guidelines recommended by the CLSI 2008, 2010 [3]. The capsule was observed in the 3 strains with optical microscope and with electron microscope. The strains expressed different levels of capsule, UBA8Ch: small sized, UBA8Md:medium sized andUBA8Gd: high sized. The UBA8Ch and UBA8Gd strains were susceptible for all the antimicrobials tested. The UBA8Md strain was intermedia susceptibility for ERY, ENR and TMS. The immune status of the host and the guttural pouch environment could influence in the phenotypic characteristics variation of the strains. Itwas isolated three strains froma same sample that expressed different levels of capsule, different colonies sizes on the blood agar plate and antibiotic sensibility. This suggests the presence of different clones of See in carriers.

isolated 3 strains with different colonies sizes on the blood agar plate, UBA8Ch (0.5mm), UBA8Md (2mm) andUBA8Gd (4 mm). Expression of capsule was observed by negative staining with India ink solution and with electron microscopywith fosfotungstic acid.Diskdiffusion testwereusedas recommended by Clinical and Laboratory Standards Institute (CLSI). The antibiotic tested were: erithromycin (ERY), penicillin (PEN), ciprofloxacine (CIP), enrofloxacin (ENR), tetracycline (TET) trimethoprim-sulfamethoxazole (TMS), cefotaxime (CTX) and florfenicol (FFC). Results were categorized by using the guidelines recommended by the CLSI 2008, 2010 [3]. The capsule was observed in the 3 strains with optical microscope and with electron microscope. The strains expressed different levels of capsule, UBA8Ch: small sized, UBA8Md:medium sized andUBA8Gd: high sized. The UBA8Ch and UBA8Gd strains were susceptible for all the antimicrobials tested. The UBA8Md strain was intermedia susceptibility for ERY, ENR and TMS. The immune status of the host and the guttural pouch environment could influence in the phenotypic characteristics variation of the strains. Itwas isolated three strains froma same sample that expressed different levels of capsule, different colonies sizes on the blood agar plate and antibiotic sensibility. This suggests the presence of different clones of See in carriers.

A 15-year-old mare mule was presented with a 2-month history of weight loss, lethargy, and anorexia. Clinicopathologic abnormalities were consistent with liver disease. Repeated urinalysis revealed hyposthenuria, but water intake and a water deprivation test were normal, suggesting adequate renal function. Ultrasonography revealed pulmonary, hepatic, and renal masses. Cytologic and histologic examination of pulmonary aspirates and hepatic biopsies, respectively, revealed polygonal neoplastic cells with many mitotic figures, the cells having the characteristics of adenocarcinoma. Necropsy confirmed a primary renal adenocarcinoma with metastasis to liver, lung, lymph nodes and the opposite kidney.

The medical records of 11 horses with idiopathic muscular hypertrophy (MH) of the small intestine were reviewed to determine the clinical and pathological features of the disease. The median age of affected horses was 10.0 years (range 5-18 years). No breed or sex predisposition was apparent. Ten horses (91%) had chronic (23 days to 2.4 years) signs of mild, intermittent colic, and 1 horse had signs of severe colic of only 3 days' duration. Partial anorexia and chronic weight loss of variable duration (1-6 months) were prominent historical findings in 5 (45%) horses. Diagnostic tests, with the exception of exploratory caeliotomy, were ineffective for definitive diagnosis of intestinal MH as a cause of colic. In 2 horses, however, a thickened, rigid ileum was detected by palpation per rectum, and in 5 horses, multiple loops of distended small intestine were detected by palpation per rectum. Hypertrophy of both the circular and longitudinal layers of muscularis was determined as the cause of intestinal thickening in all horses. Muscular hypertrophy of the ileum was present in 9 (82%) horses. Two horses (18%) had MH of a section of jejunum only, and 4 (36%) horses had MH of the ileum in combination with MH of other sections of small intestine. Two (18%) horses had MH of the entire small intestine. In 9 (82%) horses, intestinal MH resulted in narrowing of the luminal diameter at the site of MH. Small diverticula were present on the mesenteric border of the hypertrophied ileum of 5 (45%) horses. Five linear (up to 150-cm) diverticula were present in the hypertrophied jejunum of 1 (9%) horse. Haemomelasma ilei was present on the antimesenteric serosal surface of affected intestine of 8 (73%) horses. Full-thickness rupture of the ileum with subsequent diffuse, septic peritonitis occurred in 3 (27%) horses.

Splenic and hepatic ultrasonography were beneficial for diagnosis of lymphosarcoma in 3 horses with anorexia, weight loss, and lethargy. Ultrasonographic abnormalities of the spleen included a large, complex, hypoechoic mass in 1 horse, multiple well-marginated, hypoechoic nodules in 1 horse, and diffuse hyperechogenicity in another horse. Ultrasonographic abnormalities of the liver included a spherical, hypoechoic nodule in 1 horse and diffuse hyperechogenicity in another. Histologic examination of ultrasound-guided biopsy specimens or aspirates revealed lymphosarcoma. Necropsy findings confirmed diagnosis of lymphosarcoma in all horses. Necropsy findings of the liver and spleen correlated well with antemortem ultrasonographic images.

A diaphragmatic hernia in which 90% of the large colon had herniated through a 16-cm linear tear in the diaphragm was found in a 12-year-old Quarter Horse mare. Clinical signs included lethargy and exercise intolerance. Diagnosis of diaphragmatic hernia was made based on careful thoracic auscultation, combined with ultrasonographic and radiographic examination of the thorax.

An endometrial adenocarcinoma with metastases to the lung, liver, spleen, mesentery and serosal peritoneal surfaces was found in an 11-year-old Arabian mare. Clinical signs included generalized weight loss, depression, anorexia, ventral edema and abdominal distension. Ascites was due to thrombosis of the caudal vena cava. The diagnosis of endometrial adenocarcinoma was based on the histological appearance of uterine glandular epithelium and the presence of similar tissue in the metastatic tumors.