Journal of Equine Veterinary Science - Articles in Press

Bromocriptine Treatment for Inappropriate Lactation in Mares: A Case Report - Corrected Proof

2012-05-10

Abstract: Transient mammary gland development and lactation can occur eventually in weanling foals, yearlings, and adult mares without previous or recent history of pregnancy. The etiology of this condition has not been well documented, and there is limited information on the occurrence, frequency of episodes, composition, and treatment of galactorrhea secretion. This article reports a case of Brazilian Sport Horse mare, aged 10 years, with persistent lactation during 5 months. The treatment consisted of bromocriptine 0.04 mg/kg, b.i.d., orally, for 10 days, associated with hydrotherapy for 20 minutes, twice daily. After 20 days of the treatment onset, the mare was reevaluated, and a significant decrease in the volume of the udder and the amount of secretion produced was noted, and its aspect was clearer (serous) and consisted of more fluid compared with the one collected before treatment. No other clinical alterations or associated diseases were identified. Based on these findings, we suggest the diagnosis of idiopathic inappropriate lactation. Although there is no information about pharmacokinetics and description of the oral bromocriptine use in horses, being a therapeutic option for inappropriate lactation treatment in mares, it was effective at the recommended dosage.

The Effect of Exercise and Nutritional Supplementation on Proinflammatory Cytokine Expression in Young Racehorses During Training - Corrected Proof

2012-05-10

Abstract: The inflammatory response to vigorous exercise ranges from the mild symptoms of delayed-onset muscle soreness to debilitating injuries affecting soft tissue, joint, and bone. Although there is a great deal of information available on the inflammatory response to exercise in human athletes, less information is available regarding the inflammatory response to exercise in young horses undergoing training for racing careers. Here, we assessed the cytokine response to exercise in a group of young Thoroughbred racehorses during their initial training. Because there is interest in nonpharmacologic approaches to control or ameliorate exercise-induced inflammation, we also examined the anti-inflammatory effect of a nutritional supplement fed to half of the horses undergoing training. Twenty-five Thoroughbred horses aged 2 years were followed through their initial race training. Peripheral blood samples were collected at various times during the exercise for the quantitation of lactic acid, oxidative stress, and inflammatory cytokine gene expression. There was an intensity-dependent effect of exercise on lactate, malondialdehyde, and proinflammatory cytokine gene expression. Although training itself was associated with an overall reduction in inflammatory markers, horses receiving the supplement exhibited further reductions in their indicators of inflammation. As such, this study provides novel evidence of nutritional supplementation reducing postexercise inflammation.

Epidemiological Aspects in the Leptospira spp. and Toxoplasma gondii Infection in Horses from Botucatu, São Paulo, Brazil - Corrected Proof

Carla J. Coiro, Helio Langoni, Rodrigo C. da Silva — 2012-05-07

Abstract: Leptospirosis and toxoplasmosis are zoonoses with high importance because of the economic and public health impact. This study was aimed to determine the seroprevalence of leptospirosis and toxoplamosis in 714 serum samples of horses from different farms from Botucatu, São Paulo, Brazil. The samples were researched for Toxoplasma gondii antibodies by indirect immunofluorescence antibody test (IFAT) and for Leptospira spp. antibodies by microscopic agglutination test. Of 714 serum samples, 128 (17.9%; 95% CI: 15.3%-20.9%) were positive for one or more serovars of Leptospira spp., with icterohaemorrhagiae, canicola, and castellonis as the most prevalent serovars, whereas 42 (5.9%; 95% CI: 4.4%-7.9%) were positive for T gondii, of which 33 samples (78.57%; 95% CI: 64.0%-88.2%) presented a titer of 16, 7 (16.7%; 95% CI: 8.4%-30.7%) a titer of 64, and 1 (2.38%; 95% CI: 0.6%-12.3%) a titer of 256. No significant difference was found among the results obtained and the associated variables such as age and sex.

A Comparative Study Evaluating Three Bioscaffold Augmentation Devices Used for Superficial Digital Flexor Tenorrhaphy in Donkeys (Equus Asinus) by Magnetic Resonance Imaging and Ultrasonography - Corrected Proof

El-Sayed A.A. El-Shafaey, Gamal I.A. Karrouf, Adel E.I. Zaghloul — 2012-05-07

Abstract: Little is known about using magnetic resonance imaging (MRI) in evaluating the healing properties of superficial digital flexor tenorrhaphy in equines. The present study was designed to carry out in vivo comparative evaluation of normal and repaired superficial digital flexor tendon (SDFT) in donkeys, based on MRI, ultrasonography, clinical and histopathological features. Eighteen clinically healthy donkeys were assigned for three treatment trials (n = 6) using three bioscaffold materials (bovine pericardium xenograft, tendon allograft, and allograft shielding by bovine pericardium), in addition to six healthy donkeys to serve as control group. Clinical signs for each animal were scored, and the sum of all clinical indexes was calculated. MRI and ultrasonographic examinations of each donkey were carried out at 45 and 90 days postoperatively in the three treated groups, and were compared with those in the control group. Both clinical and imaging characteristics were compared and statistically analyzed at each time point. The echogenicity (P < .0039), cross-sectional area (P < .0490), and fiber alignment (P < .0077) were different at 45 and 90 days postoperatively in the shielding group than in the other two groups, with no difference in the histological features in comparison with the control group, based on the median and range analysis at 90 days postoperatively. In conclusion, MRI and ultrasonography initiate a new paradigm in monitoring the healing progression and case prognosis of SDFT tenorrhaphy with the bioscaffold augmentation devices, either xenogenic or allogenic, which provided a good alternative technique and an accelerated SDFT healing with minimal adhesions in donkeys.

Evaluation of Capsule Permeability in the Equine Blastocyst - Corrected Proof

2012-05-07

Abstract: Recipient pregnancy rates following transfer of frozen-thawed blastocyst stage equine embryos remain low. To date, no protocol has been developed that would allow successful cryopreservation of this stage of embryos. These experiments characterized the amount of glycerol entering equine embryos after incubation in 1.4 M and 3.4 M glycerol solutions using tritiated glycerol and a liquid scintillation counter. Blastocyst stage equine embryos (n = 27) were collected and incubated for 15 minutes in either 1.4 M (n = 14) or 3.4 M (n = 13) tritiated glycerol solutions. Disintegrations per minute were then determined, and the percent glycerol uptake was calculated for each embryo. Percent glycerol uptake for 1.4 M or 3.4 M glycerol treatment groups was not different (P = .68). However, it was higher (P = .05) in embryos with a diameter of ≤600 μm (3.6%) compared with embryos with a diameter of >600 μm (0.4%). We concluded that glycerol more readily permeates into embryos with a diameter of ≤600 μm that do not possess a fully functional capsule compared with embryos with a diameter of >600 μm with a fully formed capsule.

Equine Sarcoid Associated with Cutaneous Habronemosis - Corrected Proof

2012-05-07

Abstract: Equine sarcoids are benign fibroblastic skin tumors affecting equids worldwide. Infection with bovine papillomavirus types 1 and 2 has been implicated as a major fact in the disease development; however, the cellular mechanisms underlying fibroblast transformation are still largely unknown. In the present study, a diagnosis of sarcoid was histologically assessed along with eosinophilic dermatitis. The sarcoid lesion expressed the viral oncoproteins E5 and E2, suggesting a causative role of the virus and its replication. Ribosomal DNA of the nematode Habronema muscae was also revealed in the lesion. This is the first report to describe and discuss an association of cutaneous habronemosis with equine sarcoid.

Effect of Ergopeptines Associated with Tall Fescue Ingestion on Recovery of Horses Subjected to Standardized Exercise Tests - Corrected Proof

2012-05-07

Abstract: Ten horses were paired by body weight, age, and skill level, and one of each pair was assigned to one of two groups. Horses were fed alfalfa hay and a mixture of commercial sweet feed and pellets. Horses in group A were fed fescue seed that contained both ergovaline and ergotamine (E+), whereas those in the other group were fed seed that was free from ergot alkaloids (E−). After the first 35 days, horses were switched to the opposite seed treatment. Seed was fed at 8.2% of the diet, resulting in 406 ppb of ergotamine plus ergovaline in the E+ diet. During weeks 3, 5, 7, and 10, horses were subjected to two separate standardized exercise tests (SETs). The aerobic test consisted of walking, trotting, and loping and was designed to maintain horse's heart rate (HR) to less than 150 beats per minute (bpm). The anaerobic test consisted of 40 turns in less than 4 minutes in response to the movements of a mechanical cow and was designed to increase the horse's HR to more than 150 bpm. There were no treatment effects on water consumption or sweat production. There were also no treatment effects on rectal temperature at rest or during recovery from the anaerobic SET. However, rectal temperatures were higher (P < .05) 1 and 30 minutes after the aerobic SET for horses consuming E+ seed. When horses were on the E+ treatment, HRs were lower (P < .05), both at rest and during the SET. HRs were also lower (P < .05) for the E+ treatment at 1 minute after the aerobic test and 5 and 10 minutes after the anaerobic test. Respiration rates were higher (P < .05) 30 minutes after the aerobic SET and 30 and 60 minutes after the anaerobic SET for the E+ treatment. Horses may have increased respiration rates to compensate for a reduction in the efficiency of evaporative cooling, which resulted from vasoconstriction of peripheral blood vessels.

Gastric Torsion from an Intestinal Hernia Through a Rent in the Gastrosplenic Ligament in a Horse - Corrected Proof

2012-05-07

Abstract: The present report describes an 8-year-old gelding presenting with signs of severe abdominal pain. After performing a thorough physical examination, including rectal palpation and additional diagnostic tests, an exploratory laparotomy was recommended. The jejunum was found herniated through the gastrosplenic ligament, and the stomach was severely distended with gas. Given a poor prognosis, the horse was euthanized on the table. At necropsy, the stomach appeared dilated, with an 180° horizontal gastric torsion, from left (lateral) to right (medial), dividing the organ into dorsal and ventral compartments. We believe that the chronic traction exerted by an incarcerated and distended loop of jejunum, in the dorsal aspect of the gastrosplenic ligament, associated with trauma during episodes of intense rolling, enlarged the rent until it ruptured. Because of this rupture, the lateral dorsal aspect of the stomach became unattached, predisposing it to the torsion.

Digital Agenesia in Martina Franca Donkey Foal: A Case Report - Corrected Proof

2012-04-30

Abstract: A 4-day-old male Martina Franca donkey foal was evaluated for a forelimb alteration. Clinical examination and radiographs revealed the agenesia of the distal digit. Biochemical parameters were normal, and ultrasonographic evaluation did not identify any relievable organ alteration. Karyotype study revealed an abnormality on chromosome 1. The foal was discharged with a distal limb bandage in which a palmar splint was applied. A poor prognosis for the functionality of the limb was given. In endangered species, such as the Martina Franca donkey, the excessive inbreeding could result in an increase in genetic disorders. These findings shed new light on the possible pathogenesis of the digital dysgenesia. The study of the karyotype could be a useful approach to detect genetic alterations that could or could not be expressed in the animal, especially in endangered species in which a risk of an excessive inbreeding is considerable. These defects should be considered in the choice and selection of the breeders.

Comparison of the Sedative and Hemodynamic Effects of Acepromazine and Promethazine in the Standing Horse - Corrected Proof

2012-04-30

Abstract: The objective of this study was to compare the sedative and peripheral hemodynamic effects of acepromazine (ACP) and promethazine (PTZ) in the standing healthy horse. Nine healthy Warmblood horses randomly received either intravenous ACP at 0.1 mg/kg or PTZ at 0.1, 0.2, and 0.3 mg/kg. A sedation score based on clinical examination was recorded, and systolic arterial blood pressure was noninvasively evaluated using a Doppler flow detector at the tail, just before and every 15 minutes until 60 minutes after drug injection. Hemodynamics of the median artery of the left forelimb was studied using Doppler ultrasonography just before and 45 minutes after injection of the drug, which allowed calculation of surface (SURF), diameter (DIAM), and circumference (CIRC) of the vessel and peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (MV), volumetric flow (VF), and resistivity index (RI) of the blood flow. Regardless of the dose used, PTZ had lesser sedative and hypotensive effects than ACP at 0.1 mg/kg and did not induce significant variations in SURF, DIAM, CIRC, PSV, EDV, MV, VF, and RI of the studied standing horses. Conversely, the vasodilatory properties of ACP were illustrated by a significant increase in SURF, DIAM, CIRC, PSV, EDV, MV, and VF and a significant reduction of the RI. Unlike ACP, PTZ did not induce alterations on the morphology of the Doppler waveform. PTZ appears to have less sedative and peripheral vasodilator effects than ACP, thus it could be safer than ACP in patients suffering from hypotension.

Fungal Dermatitis Caused by Aspergillus sydowii in a Thoroughbred Horse - Corrected Proof

Sang Kyu Lee, Hyun-Gu Kang, Ki-Jeong Na, Jae-Ik Han — 2012-04-30

Abstract: A 5-year-old male Thoroughbred horse was referred with alopecia, along with severe incrustation, scaling, and pruritus on the left flank and back, which had been in contact with a saddle for 1 year. Treatment with topical antibiotics by the owner was not effective. A fungal culture using the hair roots and exudates under the scabs showed blue-green colonies surrounded by a white band. Microscopic examination and molecular analyses of the internal transcribed spacer region, partial β-tubulin, and calmodulin genes confirmed this fungus as Aspergillus sydowii. Topical treatment with econazole ointment for 2 months was effective. This is the first report of a natural A sydowii infection in a horse.

Characterization of In Vitro Synthesized Equine Metabolites of the Selective Androgen Receptor Modulators S24 and S4 - Corrected Proof

2012-04-16

Abstract: Several selective androgen receptor modulators (SARMs) have been synthesized and investigated in humans, rats, and dogs in the past, but no data are yet available concerning the metabolism of SARMs in horses. The aryl-propionamide-derived drug candidates S24 and S4 (andarine) have a strong androgen receptor binding affinity and show distinctive specific cell answers. Although no SARM drug candidate (aiming for testosterone replacement therapy) has completed clinical trials yet, S4 has been illicitly available via the Internet. These facts led to the prohibition of SARMs by the German equestrian federation, and the (mis)use of such compounds would further represent a doping rule violation in horse racing. In this study, the drug candidates S24 and S4 were subjected to in vitro metabolism experiments with equine liver microsomal preparations from a female Quarter Horse to obtain information about potential target analytes in equine doping control analysis. The enzymatically synthesized metabolites were characterized by liquid chromatography–tandem mass spectrometry and –high-resolution/high-accuracy mass spectrometry. All observed S24 and S4 equine metabolites are in agreement with earlier in vitro and in vivo studies in humans and dogs. Nevertheless, the relative percentage of generated equine metabolites (as determined from the analytes’ response in full-scan chromatography–tandem mass spectrometry and –high-resolution/high-accuracy mass spectrometry measurements) differs considerably from the reported profiles. Although the S24 metabolite pattern is comparably balanced concerning glucuronidated and sulfonated conjugates, the major S4 metabolite was found to be the unconjugated dephenylated compound, with a proportion of more than 90%.

Development of Immunologic Assays to Measure Response in Horses Vaccinated with Xenogeneic Plasmid DNA Encoding Human Tyrosinase - Corrected Proof

2012-04-16

Abstract: Xenogeneic plasmid DNA constructs have been developed and optimized for immunotherapies targeting cancer in both humans and dogs. Specifically, plasmid vectors containing the tumor antigen tyrosinase have demonstrated immunoreactivity and clinical benefit in the treatment of melanocytic tumors in these species. Overexpression of tyrosinase has also been noted in equine melanocytic tumors, supporting its role as a valid tumor antigen in the horse. Vaccination with plasmid constructs containing tyrosinase may thus have translational immunoreactivity in the treatment of equine melanomas. Here, we describe a methodology that is highly sensitive and specific for the detection of both humoral and cell-mediated immunoreactivity against tyrosinase in equine patients. These antigen-specific immunoassays are used to measure the humoral and cell-mediated responses in a cohort of horses vaccinated with xenogeneic plasmid DNA encoding human tyrosinase. Serum humoral responses were measured using standard enzyme-linked immunosorbent assay technique against the full-length recombinant human tyrosinase protein. Peripheral blood mononuclear cells were collected from vaccinated horses and stimulated with tyrosinase-specific peptides. Cell-mediated responses were then measured using a novel quantitative real-time-polymerase chain reaction technique to determine resultant interferon-γ expression. All horses developed significantly positive humoral and cell-mediated immune responses compared with their individual prevaccination values. No adverse reactions or signs of autoimmunity were detected. Vaccination with xenogeneic plasmid DNA expressing tyrosinase appears to elicit tumor antigen-specific reactivity and should be evaluated in a larger cohort of horses with melanocytic tumors.

Application of Wavelet Filtering to Analyze Acceleration-Time Curves of Horses Trotted on Different Surfaces - Corrected Proof

Lisa Kruse, Jennifer Salau, Imke Traulsen, Joachim Krieter — 2012-04-16

Abstract: The objective of the present study was to illustrate the possibilities of wavelet filtering to denoise hoof-acceleration data measured on different surfaces. Further, three variables from the time-domain acceleration signal and two variables from the single-sided amplitude spectrum of the Fourier-transformed signal were statistically analyzed to detect the differences between the riding surfaces as well as to compare the results of the different variables. For data recording, six Warmblood horses were trotted on five different riding surfaces. The recorded acceleration data were smoothed by wavelet filtering on three levels by using the Haar wavelet as well as the fourth-order Daubechies wavelet. The hoof’s landing phase was extracted from the acceleration signal by a special algorithm and analyzed because of to its significance with regard to the injury risk of a horse. More accurate hoof’s landing phases could be detected by the algorithm in the first and second approximations of both wavelet-filtered signals than in the original signal. The dissected hoof’s landing phases were used to calculate the aforementioned variables. The statistical analysis showed similar results within the variables of the time-domain signal and within the variables of the single-sided amplitude spectrum. The least square means of the original signal and the first and second approximation of both wavelet-filtered signals were on a similar level. In conclusion, it was shown that wavelet filtering is a suitable method to denoise acceleration-time curves. Further, the results of the five variables showed that the insertion of time- and frequency-domain variables was significant in the analysis of the acceleration data.

Lipid Utilization Pathways Induced by Early Training in Standardbred Trotters and Thoroughbreds - Corrected Proof

2012-04-16

Abstract: Controversial results on lipid utilization as an energy source during training in horses are found in the literature. The objective of this study was to assess blood lipid profile during different training programs in horses. Seventeen Standardbred horses (400 ± 50 kg) and 17 Thoroughbred horses (380 ± 15 kg) followed different training programs. Blood lipid profile, including triglycerides (TGs), total cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein (LDL), was analyzed, and very-low-density lipoprotein (VLDL) concentration was calculated. Data were analyzed using Student t test, and linear regressions were done. Cholesterol and LDL decreased during training programs in Standardbred trotters (P = .0001 and P = .0053, respectively), and VLDL was found to be close to the significance level (P = .053). Blood lipid profile, including TGs (P = .0014), cholesterol (P = .0057), HDL (P = .0128), LDL (P = .0091), and VLDL (P = .0014), varied throughout the training program in Thoroughbred horses. Negative slope of blood lipids and positive slope of TG linear regression in Standardbred trotters were significant for all parameters (P ≤ .05), whereas cholesterol and LDL regression showed poor P and r2 values and HDL P value was slightly above the significance level (P = .069) in Thoroughbred horses. TGs and VLDL showed a positive linear trend in Thoroughbred horses (P = .002). Exercise and different training programs lead to significant variations of lipid profile and lipid utilization in horses. Lipid utilization as an energy source improved with training in Standardbred trotters, whereas this was not the case in Thoroughbred horses. Further studies on the effect of training programs using different conditions and horse breeds would be necessary to understand lipid utilization as an energy source in athletic horses.

Clinicopathological Features of Hemangioma in Two Young Horses - Corrected Proof

2012-04-16

Abstract: The clinicopathological and immunohistochemical features of two vascular tumors in two young horses are described in the present work. These animals were referred to the Veterinary Teaching Hospital of the University of Córdoba because of the presence of hyperpigmented plaques located in the medial aspect of the left leg and also around the hock (case 1) and in the right front leg (case 2). Some of the lesions showed deep ulceration and severe protrusion with abundant bleeding. The histopathological study revealed that lesions were composed of nonencapsulated, proliferated, closely packed small blood vessels, some of which showed irregular shape, whereas others were similar to capillaries, arterioles, and venules. Neoplastic cells expressed vimentin and factor VIIIar, suggesting their endothelial nature, whereas in the wall of some proliferated vessels, some cells expressed vimentin, α-smooth muscle actin and desmin, an immunophenotype consistent with pericytes, and small muscle cells. These features agree with those reported in human juvenile hemangioma rather than with hemangioma in adult horses.

Changes in Eye Temperature and Stress Assessment in Horses During Show Jumping Competitions - Corrected Proof

2012-04-16

Abstract: High stress levels in horses during sporting events can influence the animal’s performance in competitions as well as their welfare. This study investigated the use of infrared thermography (IRT) measurement as a rapid, noninvasive, and accurate method for stress assessment in horses during sport competitions and compared IRT with a commonly used physiological method used for stress assessment and salivary cortisol. IRT and salivary cortisol responses were measured 3 hours before the competition, immediately following the competition, and 3 hours after the competition, each day during the 3 days of a show jumping event. Salivary cortisol values ranged from −0.11 ± 4.51 ng/mL in 5-year-old animals to 1.10 ± 2.20 ng/mL in 4-year-old animals, whereas eye temperature values ranged from 35.84 ± 1.16°C in 6-year-old animals to 36.08 ± 1.11°C in 5-year-old animals. The results obtained suggested that IRT measurements constitute an effective method for detecting stress in horses subjected to the acute events of show jumping.

On the Current Situation of Glanders in Various Districts of the Pakistani Punjab - Corrected Proof

2012-04-16

Abstract: Glanders is a highly infectious and zoonotic disease of solipeds caused by Burkholderia mallei. Progressive loss of efficiency and fatal outcome resulted in massive economic losses, which forced veterinary authorities throughout the world to implement disease control measures; these measures included mass testing using the complement fixation test and/or malleinization, and the culling of positives. This led to the eradication of glanders from Western Europe and North America in the 1950s. However, in the last decade, the number of outbreaks in Asia and South America increased steadily, and glanders regained the status of a re-emerging transboundary disease. Pakistan has been an endemic country for the past 120 years, but concise data on the presence of disease are not available. A total of 533 serum samples were collected from draught equines, a suspected risk group for glanders, from various districts of Punjab in Pakistan. The complement fixation test and the highly sensitive Western blot technique were used for serodiagnosis. No animal (horse, mule, and donkey) was found to be positive for infection. Glanders seems to be restricted to remote, sporadic pockets of endemicity and may cause outbreaks after being introduced into naive populations by (asymptomatic) shedders.

The Effect of Soaking on Protein and Mineral Loss in Orchardgrass and Alfalfa Hay - Corrected Proof

Krishona Lynn Martinson, Marcia Hathaway, Hans Jung, Craig Sheaffer — 2012-04-16

Abstract: Nonstructural carbohydrates are usually targeted for reduction during hay soaking, however, other essential nutrients may also be lost. The objectives of this research were to determine the impact of water temperature and time of soaking on reduction of protein and minerals from alfalfa and orchardgrass hay. The experimental design was a randomized complete block with six replications (n = 192). Hay types included bud and flowering alfalfa (Medicago sativa L) and vegetative and flowering orchardgrass (Dactylis glomerata L). Flakes were soaked for 15, 30, and 60 minutes in 25 L of cold (22°C) and warm (39°C) water, and for 12 hours in cold water. Changes in crude protein concentration after soaking had no effect (P > .05) on alfalfa-bud or flowering orchardgrass hay. However, crude protein concentration increased (P = .02) as soaking length increased in vegetative orchardgrass, and decreased as soaking length increased (P < .001) in flowering alfalfa hay. Soaking did not affect (P > .05) calcium (Ca) concentrations in flowering alfalfa and orchardgrass; however, Ca (P < .001) was reduced as soaking length increased in alfalfa-bud and vegetative orchardgrass hay. Reductions in phosphorus (P), potassium, and magnesium concentrations occurred with longer soaking times, resulting in high Ca:P ratios after 12 hours of soaking (P < .001). Soaking for 15-60 minutes did not result in nutrient deficiencies based on the requirements of a 500-kg horse in light work. However, supplementation of P after feeding hay soaked for 12 hours would be necessary to address high Ca:P ratios.

Equid Herpesvirus-Associated Abortion in Poland between 1977-2010 - Corrected Proof

Barbara Bażanów, Natalia Jackulak, Magdalena Florek, Zdzisław Staroniewicz — 2012-04-12

Abstract: Equid herpesvirus 1 (EHV-1) isolation and direct immunofluorescence were performed on tissues from 452 aborted and stillborn foals, which were submitted to the Pathology Department of Wrocław University of Environmental and Life Sciences, Poland, from different farms in Poland between 1977 and 2010. Although case submissions were received year-round, the number of submitted abortions peaked in the month of January, and then gradually decreased until June. EHV-1-associated abortion or neonatal death was diagnosed in 106 cases. At the beginning of the investigations (late 70s), there were a few cases of the EHV-1 abortions, but in the first half of the 80s, EHV-1 was not isolated. Until 1990, the percentage of abortion ranged from 0% to 50%, reaching its peak in 1984. A similar situation was observed during the next two decades. In 1991, 1998, 2007, and 2008, there was no isolation, and the highest rate (50%) was noticed in 1996 and 2000. The results of this study indicate that EHV-1 in Poland remains an important cause of pregnancy loss in horses, despite extensive vaccinations.

Emotional Response of Naive Purebred Arabian Colts and Fillies to Sympathetic and Traditional Training Methods - Corrected Proof

Witold Kędzierski, Iwona Janczarek, Anna Stachurska — 2012-04-12

Abstract: The aim of this study was to explore the hypothesis that the emotional response of naive purebred Arabian colts and fillies to initial training is lower in the case of sympathetic methods compared with the traditional training methods, and that the response is differentiated with regard to the sex. A group of 32 young purebred Arabian horses was included in the initial training. Half of the group was subjected to a natural training method, and the other 16 horses were trained using a traditional method. Both groups comprised an equal number of colts and fillies. The training lasted a few days, as shortly as possible, with regard to individual horse’s needs. The emotional response of horses to training process was assessed with heart rate measured telemetrically. A horse’s response to sympathetic and traditional training methods depends on its sex. The sympathetic training method modifies the response of colts more than it influences the response of fillies. It is concluded that the natural method is particularly desired in training colts.

Evaluation of Equine Albumin Solution in Fluid Therapy in Horses with Colic - Corrected Proof

2012-04-12

Abstract: Equine albumin solution can be a good therapeutic option in fluid replacement for treatment of horses with colic. The purpose of this study was to evaluate the effects of initial fluid therapy with equine albumin solution in horses presenting with colic and mild-to-moderate dehydration, and to compare this therapy with fluid therapy based on crystalloids alone. Nineteen horses of both genders presenting with colic and mild-to-moderate dehydration were used. Animals were randomly assigned to one of two groups (control: fluid therapy based on crystalloid solutions; experimental: fluid therapy based on equine albumin and crystalloid solutions). Physical examination, hematocrit determination, blood gas analysis, serum biochemistry, blood and peritoneal lactate assessment, and measurement of colloid osmotic and arterial pressure were performed at predetermined times. Good results were obtained with equine albumin solution. More fluid is attracted into and maintained in the intravascular compartment, despite infusion of small volumes, as indicated by higher arterial pressure, lower capillary refill time, lower hematocrit and serum protein concentrations, lower colloid osmotic pressure, and better skin turgor. Equine albumin solution has good oncotic action and is a safe fluid therapy option for horses with colic and mild-to-moderate dehydration. Our results suggest it can be a good choice of fluid for correction of severe dehydration, although further research is necessary to determine the adequate dose in such cases.

Marjolin’s Ulcer in Two Horses with Hereditary Equine Regional Dermal Asthenia - Corrected Proof

2012-04-12

Abstract: Two Quarter Horse mares with hereditary equine regional dermal asthenia (HERDA) were diagnosed with metastatic squamous cell carcinoma (SCC) associated with chronic nonhealing wounds. The lesions were similar to the development of SCC from chronic nonhealing ulcers, known as Marjolin’s ulcers in humans. The horses showed recurrent skin wounds in the saddle and paralumbar regions and were confirmed by molecular techniques as having HERDA. Both horses were maintained as research animals for prolonged periods and received regular veterinary care and wound treatment. Both horses were ultimately euthanized because of their chronic progressive wounds, coupled with declining health. At necropsy, the nonhealing wounds were found to be complicated by infiltrative SCC; both horses had metastasis to lungs. Chronically inflamed, recurrent skin wounds that heal slowly and incompletely as a consequence of HERDA are proposed as a major pathogenetic factor in tumorigenesis. Consistent findings with respect to proliferation index (Ki-67) and mutations of p53 tumor suppressor gene were confirmed by immunohistochemistry in one horse. SCC consistent with Marjolin’s ulcer has been previously suggested in association with chronic ulcers or burn scars in horses, but this is the first report of an association with chronic poor healing wounds in HERDA horses.

Influence of Steroidal Anti-Inflammatory Drugs on Viability and Fertility of Equine Semen - Corrected Proof

2012-04-12

Abstract: Considering the efficiency of steroidal anti-inflammatory drugs (SAIDs) in the immunomodulation of breeding-induced endometritis and the possibility of using these drugs by intrauterine route instead of the parenteral application, the present study aimed at evaluating the effect of SAIDs added to the semen extender on equine sperm viability and fertility. In experiment 1, 15 SAIDs were individually added to a skim milk-based extender and, based on the results of sperm motility, dexamethasone was the drug of choice for the subsequent trials. The effect of dexamethasone on the viability of fresh and 24-hour cooled semen was investigated in experiment 2. In experiment 3, fertility rate was measured in both post-breeding endometritis-resistant and susceptible mares. Although dexamethasone supplementation caused a premature decrease in sperm total and progressive motility and in sperm velocities (P < .05), no difference was observed for sperm membrane integrities and fertility (P > .05). Based on these results, we can conclude that dexamethasone can be added to equine semen at the time of insemination or before cooling, although its use was not able to increase fertility.

Effective Evaluation of Equine Extension Programs - Corrected Proof

2012-04-09

Abstract: Evaluation has become a more significant component of planning and delivering extension programs, as federal partners and granting agencies are requesting information on program and integrated grant outcomes, including participant learning gains, behavior change, and program-generated impacts. Effective evaluation of equine extension programs involves a balance between asking enough well-designed questions to obtain desired information and keeping the evaluation tool brief enough to encourage participant completion. For most faculties, the difficulty with evaluation lies in developing appropriate and useful questions. The objective of this article was to share examples of questions successfully used to evaluate six key equine extension program areas: participant demographics, program logistics, participant behavior change, participant knowledge gain, teaching effectiveness, and program impact. Data generated by postprogram evaluations can be a source of statistically sound information that can be shared with administration, stakeholders, and granting agencies. Extension personnel can use evaluation data to improve planning and delivery of extension programs and to demonstrate teaching ability and program impacts.

Influence of Track Surface Condition on Racing Times of Thoroughbred Racehorses in Flat Races - Corrected Proof

Yousuke Maeda, Michiko Tomioka, Michiko Hanada, Masa-aki Oikawa — 2012-04-09

Abstract: The purpose of this study was to analyze the effects of race track surface condition on the racing time of Thoroughbred racehorses in flat races isolated from the effects of differences in racecourse and racing distance. The effects of track surface condition, racecourse, and racing distance on the racing time of Thoroughbreds in flat races at 10 Japan Racing Association racecourses during a period of 5 years (2000-2004) were evaluated using multiple linear regression analysis. Track surface condition significantly affected the race time, although this effect differed between turf and dirt courses. On turf courses, racing times for different track surface conditions were, from shortest to longest, in order of firm

Bacterial Endocarditis in Two Spanish Foals After Neonatal Septicemia - Corrected Proof

Ana Muñoz, Cristina Riber, Pablo Trigo, Manuel Gómez-Díez, Francisco Castejón — 2012-04-09

Abstract: Equine neonatal septicemia could lead to the release of thrombus and heart valvular endocarditis. A relationship between activation of the renin-angiotensin-aldosterone-vasopressin (RAAV) axis and heart failure has been described in several species. This article describes the echocardiographic, electrocardiographic, and laboratory findings, including RAAV axis, in two Spanish foals with endocarditis after septicemia in comparison with two control groups matched by age and gender. Two Spanish foals (F1, 60-day-old colt; F2, 76-day-old filly) were presented with poor growth rate a month after being hospitalized because of septicemia. Colt F1 had hypercortisolemia and increased left ventricular internal dimensions in systole and diastole, increased left ventricular free wall thickness in diastole, interventricular septum thickness in diastole, and mitral valve thickness. Colt F1 also presented lower fractional shortening, ejection fraction, fractional wall thickness, and fractional septum thickness. Filly F2 showed hyperfibrinogenemia and increased values for aspartate aminotransferase, lactate dehydrogenase, creatin kinase, alkaline phosphatase, interventricular septum at systole, aorta diameter at the level of valve leaflets and sinotubular junction, and mitral and tricuspid valve thickness. The foals did not present systemic signs compatible with heart failure, heart arrhythmias were not found, and RAAV values were within the expected confidence limits. In conclusion, endocarditis without clinical signs of heart failure can appear shortly after septicemia in equine neonates. The measurement of the thickness of the valves by two-dimensional echocardiography is diagnostic. The lack of activation of RAAV in both foals might indicate that the severity of the heart problem was mild.

Quality of Raw and of Cold-Stored Semen in Icelandic Stallions - Corrected Proof

Fredi Janett, Konrad Sacher, Michael Hassig, Rico Thun — 2012-04-06

Abstract: The aim of the present study was to evaluate the quality of raw and cooled semen in Icelandic stallions. Experiments were performed using seven stallions aged between 3 and 19 years. From each stallion, six ejaculates were collected, and semen quality was determined. Thereafter, the semen was split into eight equal parts and processed with and without centrifugation using the extenders INRA 82-egg yolk, INRA 96, GENT, and Equi-Pro to a final concentration of 30 × 106 sperm/mL. The extended semen was then cooled in an Equitainer, where it was stored for 24 hours, and subsequently refrigerated for another 24 hours at 5°C. Immediately after dilution as well as after 24 and 48 hours storage, sperm motility was analyzed using computer-assisted sperm analyzer, and viability was assessed after dual DNA staining with SYBR-14 in combination with propidium iodide. The results show that the stallion had a significant (P < .05) influence on all variables evaluated in raw semen, and mean (±SEM) values of 43.4 ± 4.3 mL for the volume, 193.0 ± 17.0 × 106 sperm/mL for the concentration, 6.7 ± 0.5 × 109 for total sperm and 73.5 ± 2.1% for total sperm motility, 48.7 ± 2.0% for progressive motility, and 65.3 ± 2.0% for rapid cells were measured. In the cold-stored semen, all variables were significantly (P < .05) influenced by the stallion, extender, and storage time (48 hours). Except for Equi-Pro, all extenders examined were suitable for cooled semen preservation. For storage of more than 24 hours, centrifugation and removal of the seminal plasma were advantageous for all extenders with the exception of Equi-Pro.

Comparative Evaluation of Three In Situ Castration Techniques for Sterilizing Donkeys: Incision–Ligation (a Novel Technique), Section–Ligation–Release, and Pinhole - Corrected Proof

2012-04-06

Abstract: Castration is one of the most common surgical procedures performed in equines and is associated with various complications, such as severe hemorrhage and evisceration. Using clinical, hormonal, and histopathological findings, this study aimed to evaluate a novel in situ castration technique and compare it with two other in situ techniques, namely, “section–ligation–release” (SLR) and “pinhole” (PH), to choose the most compatible and safe technique for sterilizing donkeys. Fifteen adult male donkeys were divided into three groups (five animals each). The vascular and the nonvascular parts of the spermatic cord were double ligated separately after opening the skin and the tunica vaginalis at the scrotal neck in the first group (incision–ligation [IL] technique, IL group). In the second group, donkeys were subjected to in situ castration using SLR technique, where both parts of the spermatic cord were triple clamped, ligated, and transected (SLR group). In the third group, percutaneous ligation of the spermatic vessels was performed without opening the skin (PH technique, PH group). The PH technique was less effective and failed to induce necrosis in the testes in situ. Also, Testosterone hormone levels remained elevated 60 days after this procedure. Although the IL and SLR techniques result in convincing reductions in resting and human chorionic gonadotropin–stimulated testosterone levels in treated donkeys, IL and SLR techniques were conducted under narcosis and strict asepsis. We concluded that the PH technique should not be recommended for sterilizing donkeys. Meanwhile, the IL and SLR techniques can be considered as an alternative to other conventional methods used for sterilizing donkeys.

Comparison of Skin Prick Tests with In Vitro Allergy Tests in the Characterization of Horses with Recurrent Airway Obstruction - Corrected Proof

Paula Tilley, Jose Paulo Sales Luis, Manuel Branco Ferreira — 2012-04-06

Abstract: We intended to identify relevant immunoallergic factors and to compare skin prick tests (SPTs) and in vitro allergy tests in the characterization of horses with recurrent airway obstruction (RAO), so as to ascertain that SPTs perform better. Forty Lusitano/cross-Lusitano horses (30 RAO cases and 10 healthy control horses)—a very valuable autochthonous breed—were studied. Clinical history, thoracic radiography, respiratory tract endoscopy, and bronchoalveolar lavage were used for diagnosis. Serum samples of all 40 horses and undiluted bronchoalveolar lavage fluid samples of 21 RAO horses and 6 control horses were submitted for evaluation by an allergen-specific immunoglobulin E (IgE) enzyme-linked immunosorbent assay. SPTs were performed on the 40 horses. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for all diagnostic methods. Agreement between diagnostic methods was assessed by kappa statistic (Κ). Chi-square test with Yates correction showed SPT results from the RAO and control groups to be statistically different (P < .05). SPTs showed higher sensitivity, specificity, positive predictive value, and negative predictive value than both enzyme-linked immunosorbent assay tests. In human medicine, SPTs are considered to be the gold standard of allergy tests. Neither serum IgE nor bronchoalveolar lavage fluid IgE reliably detected allergen hypersensitivity, compared with SPT. SPTs performed significantly better overall than both in vitro tests. Low sensitivity of the in vitro assays indicates the need for continued study to elucidate a more sensitive specific IgE test.

Circulating β-Endorphin, Adrenocorticotropin, and Cortisol Concentrations of Horses Before and After Competitive Show Jumping with Different Fence Heights - Corrected Proof

Adriana Ferlazzo, Pietro Medica, Cristina Cravana, Esterina Fazio — 2012-04-06

Abstract: Circulating β-endorphin, adrenocorticotropin, and cortisol concentrations were studied before and after competitive show jumping in 18 trained jumper horses aged between 11 and 13 years and having the same level of show experience. Horses were subjected to the same type of management and daily training exercise. Each horse had been ridden by the same rider during both the daily training exercise and show jumping event. All horses, randomly divided into three groups paired by gender, performed in three competition levels with the same circuit design over 10 fences, with 5 upright and 5 cross-pole fences, differing for the fence height: group I (n = 6), 1.10 m; group II (n = 6), 1.20 m; and group III (n = 6), 1.30 m. Repeated measures analysis of variance showed a statistically significant effect of competitive exercise on β-endorphin and cortisol changes in all groups, whereas the effect of exercise on adrenocorticotropin changes was exclusively seen in groups II and III. Two-way repeated measures analysis of variance showed that the effect of fence height was significant (P = .03), and time (P = .0001) also affected cortisol changes. These results suggest that the hypothalamic-pituitary-adrenal axis response is different with respect to the different fence heights of jumping course and the different time points of the recovery period.

Factors Influencing the Frequency of Pregnancy Loss among Thoroughbred Mares in Hidaka, Japan - Corrected Proof

2012-04-02

Abstract: Pregnancy loss in mares is thought to be a main problem associated with reproductive efficiency. To clarify the situation of pregnancy loss in Thoroughbred mares in Japan, the occurrence of pregnancy loss before and after 35 days of gestation was investigated with 1,476 Thoroughbred mares in Hidaka, Japan, from 2007 to 2009. Pregnancy loss on days 17-35 was determined by ultrasound examination between 17 and 35 days after the last mating. Follow-up surveys were conducted between 35 days and foaling to determine pregnancy loss on day 35 until foaling in 843 of these mares. Using multiple logistic regression analysis, we assessed the influence of mare age, reproductive status, twin pregnancy reduction, body condition score (BCS), estrus type in foaling mares (foal heat or not), progesterone therapy, and endometrial cysts on pregnancy loss rates on days 17-35 and on day 35 until foaling in this population of mares. The pregnancy loss rates on days 17-35 and on day 35 until foaling were 5.8% and 8.7%, respectively. The overall pregnancy loss rate (day 17 until foaling, including parturient losses) was 14.7%. Risk factors for pregnancy loss included decrease in BCS between 17 and 35 days, <5 BCS at day 35, mating during foal heat, and endometrial cysts. In all, 14.7% of pregnancies were lost between day 17 and birth, contributing significantly to reduced reproductive efficiency in Thoroughbred mares in Japan. These observations indicate that mares should be maintained at high BCS and should be prevented from mating in foal heat to decrease the pregnancy loss rates.

Serum and Colostral Antibody Responses of Pregnant Mares to Salmonella Bacterins and Colostral Antibody Transfer to Their Foals - Corrected Proof

Christopher Scott Bailey, Luke Fallon, Wei Wang, Luke Borst, John Timoney — 2012-04-02

Abstract: Salmonella spp. are well-recognized foal pathogens. However, prevention of neonatal salmonellosis by vaccinating pregnant mares has not been reported previously. A formalinized adjuvanted bacterin of Salmonella enterica, serovar typhimurium (S typhimurium) and serovar newport (S newport), was given to pregnant mares to determine its safety (study 1) and potency in enhancing Salmonella-specific antibody for colostral transfer to foals (study 2). Antibody levels to S typhimurium (lysate and lipopolysaccharide [LPS]) and S newport (lysate) were determined by enzyme-linked immunoassay and reported as optical density measures. The mares in study 1 (n = 16) exhibited minimal reactions to the bacterin, and pregnancy was maintained in all mares throughout the study period. In study 2, serum antibody levels to both S typhimurium and S newport increased significantly in vaccinated mares (mean OD increase: 0.83 ± 0.58 [lysate of S typhimurium], 1.27 ± 0.82 [LPS of S typhimurium], and 0.67 ± 0.74 [lysate of S newport], respectively; n = 28). Elevated serum antibody levels on day 28 correlated with high antibody levels in colostrum (r2 = 0.62-0.75; P < .0001) and in serum samples of foals (r2 = 0.5-0.73; P < .001).

Voluntary Intake of Four Hay Types by Horses - Corrected Proof

Anne V. Rodiek, Bryn E. Jones — 2012-04-01

Abstract: Alfalfa, teff, oat, and wheat hays were fed to eight mature horses to determine voluntary intake of each hay type. After a 2-week adaptation period during which each horse was offered all four hay types each day, a 4-week study was conducted in which two horses were offered each type of hay each week, usually at the rate of 2.2% of initial body weight. Refused feed was collected and weighed the last 5 days of each week to calculate voluntary intake. Horses consumed significantly more alfalfa hay than the other hays. Wheat and teff hays were consumed in significantly lower amounts than alfalfa, but significantly more than oat hay. Across the 5 days during which voluntary intake was measured each week, hay consumption increased each day, reaching levels significantly greater than day 1 by day 4, when measured as a percentage of body weight, and day 5 when measured as a percentage of feed offered. Only alfalfa hay, at the amount consumed, met 100% of nutrient requirements for digestible energy, crude protein, lysine, calcium, and phosphorus for horses in maintenance condition. Teff hay met all nutrient requirements except digestible energy. Neither wheat nor oat hays met 100% of any of these nutrient requirements. Alfalfa and teff hays averaged about 12% nonstructural carbohydrate content (NSC), whereas wheat and oats hays contained about 30% NSC. The lower NSC content of the alfalfa and teff hays makes these more suitable for horses with problems related to carbohydrate metabolism or for refeeding starving horses.

Ultrasonography of the Collateral Ligaments of the Distal Interphalangeal Joint in Horses: Technique and Reference Images - Corrected Proof

Laurence Evrard, Géraldine Bolen, Nathalie Maquet, Valeria Busoni — 2012-04-01

Abstract: This study describes ultrasound (US) technique and reference images of the equine distal interphalangeal joint collateral ligaments (CLs), and evaluates the portion of the CLs assessable by US in a series of normal forelimbs. Transverse and longitudinal US images were obtained on five healthy horses and on 25 equine cadaver forelimbs. On six limbs, a needle was placed under US-guidance at the distal limit of visualization of each CL, and the portion of CL visible at US was evaluated on computed tomographic (CT) images. The normal CLs appear as oval structures located abaxial to the fossae of the middle phalanx in the transverse sections, obtained at the level of the coronary band. A centrodorsal hypoechoic image appears with increasing proximodistal probe inclination, demonstrating different fiber orientations within the ligament. Two main fascicles, a deep and a superficial, distally divergent, are visible on longitudinal images obtained in the central part of the ligament. The proportion of CL visible at US examination was more than 50% of the total ligament length in nine of the 12 CLs assessed by CT. Awareness of the estimated portion of distal interphalangeal joint CLs visible at US and detailed knowledge of the US technique and CLs morphology are essential to efficiently use US examination on clinical cases.

Gigantic Cutaneous Myxoma at Equine Distal Limb - Corrected Proof

2012-04-01

Abstract: An extremely large-sized neogrowth of myxoma was observed at the cannon region in a 3-year-old Arabian mare. The mass developed during the course of 4 months. The mass mechanically hindered the animal movement, exposing the mare to multiple external injuries and subsequent blood loss. The clinical parameters, morphology, and hematological and histopathological examinations of the myxoma were recorded. The body condition score of the mare was 1. The hemogram revealed moderate to severe degree of anemia. Histopathological sections assessed after surgical removal identified the mass as a myxoma. To the authors’ knowledge, this is the first report of cutaneous myxoma at equine limb in an Arabian horse.

Prostatic Masses in Geldings: Two Cases - Corrected Proof

2012-04-01

Abstract: Prostatic masses were detected in two geldings that were presented to our referral hospital for evaluation of dysuria. The masses were detected during transrectal palpation and ultrasonography of the prostate gland and were further evaluated using urethral endoscopy. A 10-year-old gelding underwent intraurethral debulking of the prostatic mass. Histopathological diagnosis was prostatic cystadenoma. The mass regrew within 9 months, and the horse was euthanized due to deteriorating clinical control of urinary continence. In another case, a 12-year-old gelding was scheduled for transurethral debulking; however, the owners decided against treatment and the horse was euthanized due to progression of clinical disease. Postmortem examination revealed the prostate to be nearly completely obliterated by the mass. Histopathological diagnosis was adenocarcinoma incorporated into a spindle cell population of unknown histogenesis. To our knowledge, these represent the first reported cases of equine prostatic cystadenoma and adenocarcinoma. In both horses, referring complaint was dysuria, and identification of the prostatic mass was made on palpation and ultrasonographic examination per rectum. Treatment options for prostatic masses in horses are limited because of the difficulty of obtaining prostatic tissue via biopsy, the surgical inaccessibility of the gland, and the apparent low incidence of occurrence. We have subsequently identified prostatic masses in two additional geldings, both also presenting for dysuria. However, the exact nature of these two apparent prostatic masses has not been definitively diagnosed with histopathological examinations to date. The prostate should be evaluated in male horses presenting for dysuria.

A Case of Equine Aspergillosis: A Novel Sampling Procedure for Diagnosis - Corrected Proof

2012-04-01

Abstract: Aspergillus spp. may induce equine respiratory infections such as fungal pneumonia, guttural pouch mycosis, and systemic infection in immunocompromised individuals. This study describes a case of probable respiratory aspergillosis in a horse presenting clinical signs of the upper airway disease different from those previously reported. Nasopharyngeal swabs and guttural pouch centesis were performed, and Aspergillus flavus was isolated and identified. Following 30 days of pharmaceutical treatment with itraconazole, clinical signs resolved. Results suggested that aspergillosis should be included in the differential diagnosis of upper airway infections, guttural pouch centesis may be useful to make a correct diagnosis, and itraconazole is efficacious in the treatment of A flavus infection.

Circumferential Ileal Rupture due to Verminous Arteritis in a Pony: A Case Report - Corrected Proof

Cathrine T. Fjordbakk, Gjermund Gunnes — 2012-04-01

Abstract: Verminous arteritis due to Strongylus vulgaris infection is a well-known cause of colic in horses; however, fatal episodes of verminous arteritis are now considered uncommon events due to efficient anthelmintic treatment strategies. The current report describes a fatal incidence of ileal devitalization with subsequent circumferential rupture caused by S vulgaris infection in an adult pony gelding in which anthelmintic treatment was regularly administered. A complete section of the ileum was rendered ischemic due to arterial thrombi containing larvae of S vulgaris, causing the ileum to rupture transversely within the ischemic segment. To the authors’ knowledge, a complete circumferential ileal rupture due to verminous arteritis has not previously been described in horses. Based on recent reports of fatal verminous arteritis due to S vulgaris infection in horses, it may be prudent to consider acute colic caused by this highly pathogenic parasite a re-emerging disease in modern horse management.

Cryopreservation of Cooled Semen and Evaluation of Sperm Holding Media for Potential Use in Equine-Assisted Reproduction Procedures - Corrected Proof

2012-03-12

Abstract: Processing stallion semen for assisted reproductive procedures, such as intracytoplasmic sperm injection (ICSI), requires special considerations regarding cooling, concentrating, and handling of sperm. The aim of experiment 1 was to determine whether cooled semen could be frozen without removal of seminal plasma and at a low sperm concentration while maintaining motile sperm for ICSI selection procedures. In experiment 2, five media for holding stallion sperm were compared to evaluate sperm motility for an interval of time sufficient for ICSI sperm selection procedures. In experiment 1, semen samples from eight stallions were cooled for 24 hours in two extenders, CST (E-Z Mixin-CST “Cool-Store/Transport” Animal Reproduction Systems) and INRA96 (Institut National de la Recherche Agronomique, IMV International Corporation), before being frozen in four freezing diluents, and were evaluated at 0, 45, and 75 minutes after thawing. The cooling extender did not significantly affect sperm motility, but modified French and glycerol egg yolk diluents provided the best sperm motility for frozen–thawed groups. In experiment 2, semen samples from seven stallions were used to test five media for holding sperm. Samples were analyzed for total and progressive motility at hourly intervals. Mean total and progressive motility were not different (P > .05) among groups from 1 through 4 hours. At 5 hours, groups differed (P = .004), with sperm held in Tyrode’s with albumin, lactate, and pyruvate having higher (P < .05) total and progressive motility than all other samples. In conclusion, motile stallion sperm can be obtained after the sperm are cooled for 24 hours, frozen, and thawed; various media are available to maintain sperm motility during equine ICSI selection procedures.

Effects of β-Hydroxy-β-Methylbutyrate and γ-Oryzanol on Blood Biochemical Markers in Exercising Thoroughbred Race Horses - Corrected Proof

2012-03-09

Abstract: In both the horse and the man, nutritional ergogenic aids have been used to improve physical ability in conjunction with an appropriate training regimen. Although training increases physical condition, the ease of taking a nutritional additive to improve training results explains the demand for supplementation, which may increase mechanical energy of work, delay onset of fatigue, or improve neuromuscular coordination. The purpose of this study was to determine the effects of oral supplementation of β-hydroxy-β-methylbutyrate (HMB) and γ-oryzanol (GO) on indices of exercise-induced muscle damage in Thoroughbred race horses. In this 32-week study, the horses were assigned to either a placebo, GO (3.0 g/d), HMB (15 g/d), or GO and HMB treatment groups. The supplements were administered for the first 16 weeks of the study during the training period before the racing season began. Blood samples were taken at baseline, and then during training, before exercise, immediately after exercise, and 30 minutes after exercise. Heart rate and speed were monitored in each exercise session. Hematocrit, glucose, lactate (LA), creatine phosphokinase, and aspartate aminotransferase were measured before and after each exercise session. Analysis of variance showed a significantly greater increase in postexercise creatine kinase activity in placebo-supplemented group than in the other treatment groups, both in the training period and during the racing seasons (P < .05). Blood LA was higher immediately after exercise in the placebo group compared with the supplemented groups. In conclusion, supplementation with HMB and GO resulted in decreased creatine kinase and LA after exercise. These findings support the hypothesis that HMB and GO supplementation helps to prevent exercise-induced muscle damage.

Effect of Restricted Grazing on Hindgut pH and Fluid Balance - Corrected Proof

Paul D. Siciliano, Sterling Schmitt — 2012-03-09

Abstract: Six mature idle geldings were used in a crossover design to determine the effects of restricted grazing on hindgut pH and fluid balance. Initially, horses were randomly assigned to a control group (CTRL: n = 3) having access to warm-season grass pasture continuously, or a restricted grazing (RG: n = 3) group having access to pasture for 12 consecutive hours (1900-700 hours) per 24-hour period for 7 days; they were then reassigned to the opposite treatment for an additional 7 days (i.e., CTRL: n = 6; RG: n = 6). Fecal samples were collected from each horse at 700 hours on day 7 of each period and analyzed for pH and dry matter (DM) as indicators of hindgut pH and fluid balance, respectively. Jugular blood samples were also collected at 700, 1300, and 1900 hours on day 7 and were analyzed for plasma protein as an indicator of systematic fluid balance. Fecal pH and DM data were analyzed using a paired t test. Plasma protein data were analyzed as a repeated-measures design. The mean (± SE) difference between CTRL and RG for fecal pH (.01 ± .16) and fecal DM (.68 ± .6%) was not significant (P = .93 and .52, respectively). Mean plasma protein concentrations were not affected by treatment or by treatment × sample time interaction, but tended to increase (P = .07) during the sampling period regardless of treatment. In conclusion, 12 hours of grazing restriction followed by 12 hours of grazing did not negatively impact hindgut pH or fluid balance.

Congenital Aneurysmal Bone Cyst in a Foal - Corrected Proof

Uneeda Bryant, Luke Fallon, Matilda Lee, Roy Pool — 2012-03-05

Abstract: A 2-week-old female Thoroughbred foal was born with a firm, expansile, progressively enlarging mass involving the left hemimandible. Grossly, the mass was composed of variably sized cavernous spaces containing clotted blood and serofibrinous exudate, separated by fibrous and fibroosseous septa. Histologically, the spaces were lined by flattened to plump spindle cells and contained hemorrhage, fibrin, and multinucleated osteoclast-like cells. The septa separating adjacent cavernous spaces contained interlacing bundles and streams of spindle cells, multinucleated giant cells, hemosiderophages, mineral deposits, and spicules and trabeculae of reactive and poorly mineralized bone. A diagnosis of congenital aneurysmal bone cyst was made based on histologic features. The pathogenesis for the development of aneurysmal bone cysts is still undetermined, although spindle cells lining cavernous spaces in the foal exhibited negative immunolabeling for factor-VIII (F8) and positive immunolabeling for smooth muscle actin, suggesting vascular smooth muscle origin and possible blood flow disturbance.

Topographical Anatomy of the Equine M. Cutaneus Trunci in Relation to the Position of the Saddle and Girth - Corrected Proof

Alexandra van Iwaarden, Narelle C. Stubbs, Hilary M. Clayton — 2012-02-10

Abstract: The aim was to investigate the topographical anatomy of m. cutaneus trunci with reference to the position of the saddle and girth and its possible role in persistent sensitivity to girth pressure. The methodology involved dissections of 12 horse cadavers to describe the topography, attachments, morphological features, and thickness of the cutaneous muscles. M. cutaneus trunci was more variable in size and shape, especially the extent and curvature of its dorsal border, than the descriptions in anatomical texts indicate. In all horses, it extended far enough dorsally to lie directly underneath the weight-bearing panels of the saddle. The muscle was substantial in size, weighing 2.6-4.3 kg and having a 1.5- to 2.7-cm thickness in the girth region. Craniodorsally, it was adherent to the underlying fascia in the scapular region. Cranioventrally, m. cutaneus trunci had a distinct fascial attachment with the tendons of m. latissimus dorsi and m. teres major on the teres major tuberosity and the glenohumeral joint capsule. From this fascial attachment, the muscle fibers radiated caudally and were intimately connected to the skin by a diffuse fibrous network. Tactile stimulation of the skin overlying the cutaneous muscle is associated with a reflex muscular contraction that twitches the overlying skin (panniculus reflex). Failure to habituate to pressure of the tack in areas overlying the m. cutaneus trunci may result in continuous stimulation of the panniculus reflex, which could play a role in persistent sensitivity to girth pressure in some horses.

Population Pharmacokinetics of Tobramycin in Horses - Corrected Proof

Aneliya Haritova, Dinyo Bakalov, Huben Hubenov, Lubomir Lashev — 2012-02-10

Abstract: Population pharmacokinetics of tobramycin was investigated in 28 healthy horses, with an aim to assess interindividual variability in the disposition of the antibiotic. Additionally, a covariate model for improved prediction of the concentrations in a particular animal was developed. A two-compartmental model best described the data. The final population covariate regression model was based on relationships between body weight and central and peripheral volumes of distribution, and between creatinine clearance and systemic tobramycin clearance. The value of population systemic tobramycin clearance and its interindividual variation (CV) were 0.087 L.hr−1.kg−1 and 6.0%, respectively. The respective values for central and peripheral volumes of distribution were 0.652 L.kg−1 with CV of 17.7% and 1.56 L.kg−1 with CV of 4.5%. In horses with decreased glomerular filtration rate, lower tobramycin clearance is predicted with the population model that requires administration of lower dose than that accepted for treatment of horses with normal kidney function. Population pharmacokinetic analysis allows study of basic disposition of tobramycin in horses with sparse data. The prediction power of the regression model was improved by inclusion of covariables such as body weight and creatinine clearance. This model can be used in direct patient care for the construction of dosing strategy in individual clinical cases.

Environmental Impacts of Equine Operations: A U.S. Department of Agriculture Multistate Project - Corrected Proof

2012-01-30

Abstract: The U.S. Department of Agriculture supports agricultural research by encouraging the formation of multidisciplinary and multi-institutional teams. Project teams focus on agricultural issues related to profitability and economic and environmental sustainability. Recently, a U.S. Department of Agriculture project to study the impact of equine management and feeding practices on the environment was approved. The project, “NE-1041: Environmental Impacts of Equine Operations,” is a Northeast regional project but includes research and extension faculty from across the country. The project team includes representatives from Alabama, Connecticut, Kentucky, Louisiana, Maryland, Michigan, Minnesota, New Jersey, North Carolina, Pennsylvania, South Dakota, and Vermont. The goal of this project is to incorporate the best available data on horse management and feeding practices, manure storage and disposal, pasture and cropping management, soil and environmental quality, erosion control, and farm management practices to minimize negative impacts of equine operations on the environment. The specific objectives of the project are to assess existing data on environmental impacts of equine operations, identify gaps in current knowledge, conduct research when data are lacking or nonexistent, and incorporate existing and newly generated data into a systematic description of nutrient flow in soil, water, and air occurring on horse farms. Estimates will be made of pathogen transports and nitrogen (N)-, phosphorus (P)-, potassium (K)-, and energy (carbon)-loss potentials. In addition to identifying system-wide losses on equine farms, another goal of the project is to assist farmers and agricultural professionals in determining the value of equine management practices and other accepted best management practices.

Refinement of Culture Conditions for Maintenance of Undifferentiated Equine Umbilical Cord Blood Stem Cells - Corrected Proof

Sarah A. Reed, Sally E. Johnson — 2012-01-30

Abstract: Umbilical cord blood (UCB) was collected from Thoroughbred mares at foaling, and stem cells were isolated. UCB stem cells were cultured in growth media (GM), GM + Fibroblast Growth Factor 2, GM + Flt3/Thrombopoietin/c-Kit ligand, or conditioned media. Population doubling times (PDTs) were calculated. UCB stem cells cultured in standard GM exhibited faster PDTs (30.07 ± 1.59 hours) than those cultured in any treatment media. PDT was further accelerated by cultivation in GM on fibronectin (26.99 ± 1.57 hours)-, collagen I (26.21 ± 1.18 hours)-, or gelatin (27.32 ± 1.50 hours)-coated surfaces. Time in culture increased PDT regardless of media or substrata conditions. Because Oct4, nanog, KLF4, Sox2, and c-myc are implicated in embryonic stem cell pluripotency, total RNA was harvested from UCB stem cells as well as mouse ES cells and analyzed by reverse-transcription polymerase chain reaction. Both populations expressed all transcripts. The persistence of Oct4, nanog, and Sox2 expression in UCB stem cells was monitored over time in culture. Oct4 was detected throughout the duration of the experiment. Sox2 and nanog expression was lost with time in culture. Cells cultured on protein matrices maintained nanog expression longer than those on uncoated plasticware. These phenotypes remain unaffected by the type of culture matrix and FGF2. However, the plasticity markers are lost with serial passage.

First Report on the Frequency and Molecular Detection of Neuropathogenic EHV-1 in Turkey - Corrected Proof

2012-01-30

Abstract: There has been an increase in outbreaks of neuropathogenic equine herpesvirus-1 (EHV-1) in the United States and Europe. However, the presence and frequency of neuropathogenic EHV-1 in Turkish horses are not known at present. This study aimed to investigate the frequency of EHV-1 and neuropathogenic strains of EHV-1 in the Marmara Region of Turkey. Samples were analyzed for the presence of EHV-1 and neuropathogenic EHV-1 by real-time PCR TaqMan probe assays. Overall detection rate of EHV-1 was 45.5% (51 of 112). The detection rates were 70.5% (24 of 34) in aborted fetuses, 53.3% (8 of 15) in neonatal deads, 66.6% (4 of 6) in foals, 40% (2 of 5) in dead mares, and 25% (13 of 52) in living mares. Overall detection rate of neuropathogenic EHV-1 was 7.8% (4 of 51), and the real-time PCR results were confirmed by sequencing. Neuropathogenic strains of EHV-1 were detected in the brain and lung of two mares with neurological disease but without a history of abortion, in the brain of a foal that died of respiratory disorder, and in the nasal swab from a mare with a history of abortion. On histopathology, nonpurulent meningoencephalitis, hemorrhages, and vasculitis were seen in the brain. In conclusion, results of this study indicated, for the first time, that the neuropathogenic EHV-1 is circulating in the Marmara Region of Turkey. The results of this study also show that the current risk for non-neuropathogenic strains is high, whereas risk for the neuropathogenic EHV-1-G2254 strain seems to be low. As outbreaks of EHV-1 continue in the Marmara region of Turkey, surveillance for neuropathogenic EHV-1 genotype should be maintained.

Cervical Vertebral Osteomyelitis With Secondary Septic Arthritis of the Atlantoaxial Joint in a Foal: A Case Report - Corrected Proof

James R. Crabtree, Alec Jorgensen — 2012-01-30

Abstract: A 36-day-old, 100-kg Thoroughbred colt was presented with a sudden onset of abnormal head carriage and pyrexia. Radiography revealed an osteomyelitis of the vertebral body of the second cervical vertebra. Ultrasonography revealed abscessation in the region of the atlantoaxial articulation on the left side, and fluid aspirated from the abscess confirmed suppurative inflammation. Surgical management was not feasible on economic grounds, and therefore this case was managed with aggressive medical therapy based on the most likely pathogens involved. To provide prolonged antibiotic therapy within the client’s budget, the antibiotic flucloxacillin (Staphlex, 500 mg) was used at a dose of 10 mg/kg by mouth, three times daily. Thirty-eight days after first presentation, the foal was euthanized because of chronic pain and deterioration in neurologic signs. A diagnosis of chronic osteomyelitis of the body of the second cervical vertebra (axis) was made with concurrent septic arthritis of the atlantoaxial joint involving the articular surface of the first cervical vertebra (atlas) and cervical myelopathy of the spinal cord within the first two vertebrae. No pathogens were isolated post mortem. This is the first report to describe the use of flucloxacillin in a foal. Although the outcome was fatal, the medical therapy provided could be considered successful at sterilizing the bony lesion.

Equine Infectious Anemia: Active Surveillance in Central Italy 2007-2009 - Corrected Proof

Carmen Maresca, Eleonora Scoccia, Laura Faccenda, Jacopo Zema, Silva Costarelli — 2012-01-30

Abstract: Equine infectious anemia (EIA) is an infectious and potentially fatal viral disease of equids. EIA virus is usually transmitted from horse to horse by large biting insects, such as horseflies. The aim of this study was to evaluate the results of a national surveillance plan from 2007 to 2009 and evaluate the potential risk factors of EIA in horse populations in central Italy. In 2007, 18 of 6,773; in 2008, 30 of 7,940; and in 2009, 21 of 11,666 equines tested were seropositive for EIA. No statistical association was found between location or sex and the diagnosis of EIA. The seroprevalence rate (2007-2008-2009) was higher among older equids (older than 6 years) than among young (3 months to 5 years old) (P < .05). Likewise, the seroprevalence rate (2007-2008-2009) was higher among mules than among other horses (P < .05). Until 2007, the national equine register did not exist in Italy; therefore, it was difficult to measure the percentage of untested horses that presented a real but unquantified risk for continued EIA virus transmission. By introducing new laws governing the control and conducting active surveillance for EIA, it has been possible, in Italy, to develop a firm foundation of knowledge concerning the persistence and transmission of EIA and the risk factors and to better control the spread of this infection in horses.