Warmblood Stallion Research Articles

Uncommon presentation of an invasive T‐cell lymphoma in a young Warmblood stallion

Uncommon presentation of an invasive T‐cell lymphoma in a young Warmblood stallion

Storing stallion sperm in SpermSafe™ at 17°C may improve fertility by reducing mPTP formation

Stallions with sperm that do not tolerate cooling have limited commercial potential. Cooling increases sperm intracellular calcium (Ca2+i; White, Reproduction, Fertility and Development. 1993;5:639-58), which in human spermatozoa triggers formation of the mitochondrial permeability transition pore (mPTP), leading to apoptosis (Treulen et al., Human Reproduction. 2015;30:767-76). However, the mechanism of sperm mPTP formation is yet to be described in the horse. As such, this study investigated whether mPTP formation occurs in stallion spermatozoa following Ca2+i increase and whether storing spermatozoa at higher temperatures can minimize Ca2+i increase and mPTP formation, thereby improving fertility. This would be investigated by alternatively storing sperm at 17°C in SpermSafe™ (BREED Diagnostics), a medium designed for liquid-storage at higher temperatures. Experiment 1 utilised three ejaculates from each of three pony stallions (n=9) to investigate the relationship between Ca2+i and mPTP formation. Semen was collected using an artificial vagina (AV) and extended 2:1 (extender:semen) using EquiPlus (Minitube). Spermatozoa were isolated from seminal plasma and extender using single-layer colloidal centrifugation before being resuspended to 20 × 106/ml in Biggers, Whitten, and Whittingham medium. Spermatozoa were pre-loaded with calcein-AM (fluorescent mPTP probe) and exposed to various doses of ionomycin to induce the Ca2+i increase. Data were checked for normaldistribution (Shapiro-Wilk test), with oneway ANOVA (treatment effect) and Dunnets test (comparing treatments and the control) used to identify significant differences, and ‘stallion’ used as a blocking term. The mPTP formed (loss of calcein fluorescence) following ionomycin-induced Ca2+i increase at 5 nM (100±16.4 AFU vs. 44.3±8.3 AFU for control and 5 nM ionomycin, respectively; P≤0.001), indicating that stallion spermatozoa do undergo mPTP formation in response to elevated Ca2+i. Experiment 2 utilised a fertile (83% per-cycle conception rate [PCCR] with fresh semen; n=6), 5-year-old Warmblood stallion with a history of poor fertility using cooled semen. Semen was collected and extended as described above and was washed via cushioned centrifugation. Sperm pellets were resuspended to 50 × 106/ml in either EquiPlus (cooled in a standard commercial shipper) or in SpermSafe (stored at 17°C in an EquOcyte shipper) for 24 h. Due to the logistical constraints of commercial practice, split ejaculates could not be utilized, so each sample was a separate ejaculate. Fixed-time AI was performed 24 h following semen collection and ovulation induction. Pregnancy rates of 0% (0/6) and 67% (8/12) were achieved following AI with cooled vs. SpermSafe-stored spermatozoa, respectively (Chi Square; P≤0.01). In conclusion, these data suggest that storing stallion sperm at 17°C in SpermSafe before AI may improve fertility in stallions with poor cooling tolerance, potentially due to reduced mPTP formation.

Accessory carpal bone fracture repair by means of computer‐assisted orthopaedic surgery in a Warmblood stallion

SummaryA 10‐year‐old, 595 kg Irish Warmblood stallion used for showjumping was presented with a marked right forelimb lameness at walk. The horse sustained a dorsal plane fracture of the accessory carpal bone (ACB) when falling with both carpi in flexion. The fracture was repaired by means of computer‐assisted orthopaedic surgery (CAOS) using two cortex screws placed in lag fashion. In a second CAOS procedure, a dorsoproximal fragment of the ACB was removed after further proximal displacement had become apparent. Both surgical procedures were facilitated by the application of a fibreglass cast to immobilise the carpus in extension and to allow for the placement of the patient tracker distant from the surgical site. One year after surgery, the horse had returned to full athletic activity. Neither the antebrachiocarpal joint nor the carpal sheath were distended. Control radiographs and standing cone beam computed tomography showed complete osseous union of the fracture and osteophyte formation on the caudal aspect of the radius and the proximal border of the ACB.

Peritoneal fluid accumulation in the femoral canal as a result of a post‐traumatic femoral hydrocele in a mature Warmblood stallion

SummaryThe following case report documents the clinical presentation, ultrasonographic appearance, surgical management and outcome of a horse with a traumatic tear extending from the superficial and deep inguinal rings, across the aponeurosis of the external abdominal oblique muscle and inguinal ligament, disrupting the femoral ring, vascular lacuna and peritoneum. This subsequently resulted in fluid accumulation within the femoral canal. This unusual injury and presentation gives rise to discussion of the aetiology and nomenclature that should be used to properly describe this injury.

Internal jugular vein phlebectasia in a one‐year‐old Warmblood stallion

SummaryInternal jugular vein phlebectasia (IJVP) is a saccular or fusiform dilation of the internal jugular vein without tortuosity. In human patients, it causes an asymptomatic intermittent unilateral swelling in the lower part of the neck. Although the diagnosis can be suggested based on the clinical features, confirmation by imaging techniques is necessary. This report describes the first reported case of IJVP in a one‐year‐old Warmblood horse. The horse was admitted with a large, soft intermittent swelling in the right jugular groove, especially when lowering the head. Ultrasound showed an enlarged vein (10 cm diameter) draining normally towards the heart. Furthermore, contrast‐enhanced CT (CECT) revealed a large distention of the deep venous system on the right side of the neck. Due to uncertain future athletic performance and both the extent and the complexity of the venous dilation, surgical intervention was declined and the horse was subjected to euthanasia. Post‐mortem dissection revealed a small right external jugular vein but a markedly dilated right internal jugular vein (10 cm diameter), which is normally absent in horses. Based on the imaging and necropsy findings, diagnosis of IJVP was made.

Treatment of a subchondral cystic‐like lesion in the distal scapula with a translesional bone screw in a horse

SummaryA 2‐year‐old French Warmblood stallion was presented for lameness investigation. The diagnostic procedures identified the reason for lameness as being a subchondral cystic‐like lesion (SCL) in the glenoid cavity of the scapula. The horse was surgically treated with a translesional 4.5 mm cortical bone screw inserted through the SCL under radiographic guidance. Sixty days after surgery, the horse was sound and the SCL showed significant radiographic signs of healing. Radiographs obtained 180 days after surgery showed further radiographic healing, with the SCL presenting a radiodensity similar to the surrounding bone. At 4 years post‐operative follow‐up, the horse is sound and competing successfully as a 6‐year‐old in Concours de Saut International (CSI) competitions.

Comparison of the clinical and radiographic appearance of the cervical vertebrae with histological and anatomical findings in an eight-month old warmblood stallion suffering from cervical vertebral stenotic myelopathy (CVSM)

BackgroundCervical vertebral stenotic myelopathy (CVSM) remains one of the most important abnormalities of the cervical spine resulting in neurological deficits in horses. The aim of the following study was to compare the results of the clinical and neurological examination, the results of myelography and the post mortem anatomical and histological appearance of the spinal cord and cervical vertebrae in a horse with CVSM.Case presentationThe following study describes a clinical case of an eight-month-old stallion with ataxia. Plain cervical radiographs indicated narrowing of the spinal canal. Conservative therapy using NSAIDs did not result in any improvement in the gait of the horse. Due to economic constraints, surgical intervention was excluded. The owner chose to humanely euthanise the horse. Immediately after euthanasia, post mortem myelography was performed, and measurements of the myelographic dye column were taken. They revealed a 67% DMC reduction and a 64% DD reduction at the C3/C4 level. Afterwards, an anatomical dissection was performed. The cervical vertebrae and vertebral canal were macroscopically inspected and measured and indicated a 44% narrowing of the canal at the C3/C4 level. The spinal cord was removed and underwent histological evaluation after staining. Microscopic lesions were visible at the level of the compression and included axonal degeneration with partial or complete loss of myelin in the white matter of the lateral and dorsal funiculi as well as the formation of dysfunctional so-called “spongy structures”. An increase in the number of microglial cells and collagen was also observed. The formation of glial scars was excluded. Immunohistochemical studies revealed a negative transmembrane glycoprotein CD68(−) – monocyte response and a negative tumor necrosis alpha TNFα (−) reaction.ConclusionsCVSM may be difficult to diagnose, even for experienced veterinary surgeons. Currently, an ex vivo histopathologic examination of the spinal cord is thought to be the gold standard in the diagnosis of CVSM. Our histological examination revealed no CVSM-specific glial scar formation and a CD68(−) negative and TNF-α negative reaction, which have not been previously reported. Histological lesions in CVSM may vary depending show inter-individual variability and on the treatment, which further hinders ex-vivo diagnostics.

Acute Equine Grass Sickness in a two-year old Warmblood stallion in Germany

Acute Equine Grass Sickness in a two-year old Warmblood stallion in Germany

Some notes on fatal acquired multiple acyl-CoA dehydrogenase deficiency (MADD) in a two-year-old warmblood stallion and European tar spot (Rhytisma acerinum)

Some notes on fatal acquired multiple acyl-CoA dehydrogenase deficiency (MADD) in a two-year-old warmblood stallion and European tar spot (Rhytisma acerinum) J. H. van der Kolk a , R. Boelens b , S. B.A. Halkes c , I. D. Wijnberg d , M. G.M. de Sainvan der Velden e & J. H. Ippel b a Section Equine Metabolic and Genetic Diseases , Euregio Laboratory Services , Maastricht , the Netherlands b NMR Spectroscopy Research Group, Bijvoet Centre for Biomolecular Research , Utrecht University , Utrecht , the Netherlands c PhytoGeniX BV/Medicinal Chemistry and Chemical Biology, Department of Pharmaceutical Sciences , Faculty of Sciences, Utrecht University , Utrecht , the Netherlands d Department of Equine Sciences , Medicine Section, Faculty of Veterinary Medicine, Utrecht University , Utrecht , the Netherlands e Department of Metabolic Diseases , University Medical Center , Utrecht , the Netherlands Accepted author version posted online: 20 Dec 2012.Published online: 16 Jan 2013.

Severe hindlimb lameness and pathological femur fracture in a horse secondary to haemangiosarcoma

SummaryAn 18‐year‐old Warmblood stallion was presented for an acute onset nonweightbearing right hindlimb lameness following a mild lameness of 2 weeks' duration. Severe swelling was present in the right femoral area. Despite extensive diagnostic procedures, no definitive diagnosis could be made. Packed red cell volume was persistently low. The horse improved with supportive treatment and was discharged at the owner's request. The horse presented 4 days later for bleeding from a previously made incision on the lateral femoral area. Due to deterioration of his condition, the stallion was subjected to euthanasia. Diagnosis of disseminated haemangiosarcoma, affecting primarily the hindlimb musculature and leading to pathological fracture of the femur was made at necropsy and subsequent histopathology.

Successful outcome in a case of equine multinodular pulmonary fibrosis (EMPF) treated with valacyclovir

SummaryEquine multinodular pulmonary fibrosis (EMPF) is a progressive fibrosing interstitial lung disease, which has been associated with γ‐herpesviruses. This report describes a 22‐year‐old Warmblood stallion diagnosed with EMPF on the basis of clinical examination, laboratory results, lung radiographs and ultrasound, lung biopsy and inclusion bodies found in macrophages of broncho‐alveolar lavage fluid (BALF) as well as an identification of EHV‐5 DNA by polymerase chain reaction (PCR). The horse recovered after one week of treatment with valacyclovir (40 mg/kg bwt per os q. 8 h) and is clinically healthy 2 years later. To our knowledge this is the first report describing treatment of EMPF with valacyclovir.

Gluten-dependent antibodies in horses with inflammatory small bowel disease (ISBD)

Background: Equine inflammatory small bowel disease (ISBD) is an idiopathic pathologic condition seeming to increase in prevalence. Objective: To investigate the potential role of gluten in equine ISBD. Animals & Methods: Antibodies known to be important in the diagnosis of human coeliac disease (CD): IgA antibodies to human recombinant and guinea pig tissue-transglutaminase (TGA), native gliadin (AGA), deamidated-gliadin-peptides (DGPA), and primate and equine endomysium (EMA) were assessed in blood samples from three different groups of horses: ISBD affected (n = 12) on a gluten-rich diet and controls either on gluten-rich (n = 22) or gluten-poor (n = 25) diets. Significant differences (p < 0.05) between groups were assessed using the Wilcoxon test. Results: Both ISBD-affected horses and gluten-rich controls had significantly (p < 0.0004) higher hrTGA titers than gluten-poor controls. However, ISBD horses did not show significantly increased levels of any of the CD related antibodies when compared to gluten-rich controls. Nevertheless, markedly increased antibody levels (TGA, EMA and DGPA) were found in one of the ISBD horses. The introduction of a gluten-free ration in this 14-year-old warmblood stallion resulted after 6 months in the reduction of antibody levels and clinical recovery associated with improved duodenal histopathology. Conclusion: To the best of our knowledge, this is the first study assessing gluten-related antibodies in horses and results suggest a potential pathogenic role of gluten in at least some cases of equine ISBD. Clinical importance and impact for human medicine: Given serology and concurrent clinical findings, this study warrants further investigations into the immunologic basis of possible gluten-sensitive enteropathy in horses and analogy with human disease.

Een degeneratieve gewrichtsaandoening behandeld met autologe equine mesenchymale stamcellen uit het perifeer bloed

Een vijfjarige Duitse warmbloedhengst die chronisch mank was ten gevolge van een degeneratieve aandoening in het kroongewricht en die geen verbetering vertoonde na conservatieve therapieën, werd behandeld met autologe mesenchymale stamcellen (MSC). Deze MSC werden geïsoleerd uit het perifeer bloed van de patiënt en 2,5 miljoen van deze cellen werden in het gewricht geïnjecteerd, tweemaal met een interval van acht weken. De positieve evolutie na behandeling werd gedocumenteerd aan de hand van een klinische evaluatie en objectieve drukplaatanalysen. In dit artikel wordt voor de eerste maal het gebruik van perifeer bloed beschreven als bron van MSC voor het behandelen van een degeneratieve gewrichtsaandoening bij een paard.

Cryopreservation of semen from a stallion with seminal vesiculitis

SummaryA 6‐year‐old Warmblood stallion was admitted for semen collection and cryopreservation. On the seventh and subsequent collection days semen samples were contaminated with purulent debris. A diagnosis of seminal vesiculitis was made following ultrasonography and endoscopy of the seminal vesicles. The stallion was treated with systemic and topical antimicrobial therapy and, although this did not cure the condition, subsequent ejaculates were suitable for cryopreservation.

Arthroscopic Removal of Metallic Foreign Body from the Talocrural Joint Using a Magnetic Retriever in a Horse

To report use of a magnetic retriever for arthroscopic removal of a metallic foreign body from the equine talocrural joint. Clinical report. A 2-year-old Warmblood stallion. A metallic foreign body was removed from a talocrural joint using a 10-mm magnetic retriever under arthroscopic guidance. Preoperative radiographs were used to locate the intra-articular position of the foreign body. Six months after surgery, the horse was no longer lame. A magnetic retriever can be used for arthroscopic removal of metallic foreign bodies from the equine talocrural joint. A magnetic retriever may be useful for arthroscopic retrieval of metallic foreign bodies from synovial cavities in horses, especially when direct observation is impeded by inflamed synovial villi and fibrin.

Torsion of the spermatic cord in a Warmblood stallion

Torsion of the spermatic cord in a Warmblood stallion

Chronic recurrent conjunctivitis due to Thelazia lacrymalis-induced, chronic abscess forming dacryoadenitis in a Warmblood stallion

Chronic recurrent conjunctivitis due to Thelazia lacrymalis-induced, chronic abscess forming dacryoadenitis in a Warmblood stallion

Seasonal changes in semen quality and freezability in the Warmblood stallion

The objective of this study was to investigate seasonal changes in stallion semen quality and to determine the best time for semen cryopreservation. Experiments were performed using 10 Warmblood stallions from the National Stud Farm in Avenches (Switzerland). Ejaculates were collected and frozen every other week during 1 year from January to December 1999. Volume, concentration, and motility, and the number of morphologically normal sperm and sperm with major defects (abnormal heads, acrosome defects, nuclear vacuoles, proximal droplets, abnormal midpieces) were evaluated. For all frozen-thawed semen samples motility as well as viability (SYBR-14/PI) was tested, and the hypoosmotic swelling test (HOS) was performed. To analyze seasonal differences 4 periods of 3 months each were defined: autumn (September, October, November), winter (December, January, February), spring (March, April, May) and summer (June, July, August). During the 1 year experiment all semen quality parameters showed a clear seasonal pattern. The volume, total sperm count and motility in fresh semen were significantly higher ( P<0.05) in summer than in winter, while sperm concentration was significantly lower in summer compared to the other seasons. Regarding morphology, normal sperm was significantly lower ( P<0.05) in summer than at any other time of the year and higher values ( P<0.05) were found for major defects in summer than in spring and autumn. In frozen-thawed semen motility was significantly ( P<0.05) improved in autumn when compared to spring and summer. Viability was lowest in summer and differed significantly ( P<0.05) from other seasons. The HOS test revealed significantly more ( P<0.05) membrane damaged spermatozoa in winter than in spring, summer and autumn. Our results demonstrate that in our climatic conditions clear seasonal differences occur in semen quality of fresh and frozen-thawed semen and that cryopreservation of stallion semen should preferably be performed in autumn.

Disseminated Metastatic Intramedullary Melanoma in an Aged Grey Horse

A 12-year-old grey Warmblood stallion presented with fever of unknown origin, and anaemia. Five days later it had developed ataxia and become recumbent, and was humanely killed. At necropsy, malignant melanomas were identified in the perineal subcutis, spleen, and thoracic vertebral canal (T10–11). Populations of malignant melanoma cells were scattered throughout medullary cavities of the axial and appendicular skeleton, and were identified grossly as irregular areas of black to grey discoloration. To the authors» knowledge, this is the first report of disseminated intramedullary melanoma in a domestic species.

Partial erection disorder in an eleven year old warmblood stallion - Use of electroejaculation for assessment of testicular function

Partial erection disorder in an eleven year old warmblood stallion - Use of electroejaculation for assessment of testicular function