Validation of a portable device (iSperm®) for the assessment of stallion sperm motility and concentration

The objective of this study was to evaluate the accuracy of a novel, portable device (iSperm^® Equine for assessing concentration and motility of stallion semen). In the first experiment, semen concentration was determined by the iSperm^® Equine (Aidmics Biotechnology), Androvision^® (Minitube) and NucleoCounter^® SP‐100? (ChemoMetec). The total motility and progressive motility were determined by the iSperm^® Equine and the Androvision^® using the manufacturer's guidelines. Frozen/thawed semen samples (n = 33) at various dilutions were analysed for concentration and motility with the above‐mentioned devices. There was a significant correlation between the concentrations measured with iSperm^® and NucleoCounter^® at all the measured dilutions. Moreover, <10% difference in concentrations was observed between the iSperm^® and NucleoCounter^® using the Bland–Altman test. There was also a significant correlation between iSperm^® and Androvision^® for total and progressive motility. In the second experiment, the parameters used in the Androvision^® were modified to match those of the iSperm^®. Total motility and progressive motility of frozen/thawed semen samples (n = 10) were determined, and the similarity between the Androvision^® and iSperm^® was confirmed by correlation studies and Bland–Altman test. The results of these experiments demonstrate that the iSperm^® offers a reliable and practical alternative for the semi‐automated measurement of concentration and motility of stallion semen in the field. The iSperm^® enables the practitioner to obtain objective and repeatable measurements on a variety of semen types (fresh, cooled and frozen) in the field at the time of insemination and thus acquire more insight into the quantity and quality of the provided insemination doses. This mare‐side diagnostic tool may help practitioners in identifying presumed subfertility problems more rapidly and act accordingly.     

A post-mortem study on the prevalence of peripheral dental caries in Scottish horses

Peripheral caries (PC) is an increasingly recognised equine dental disorder with unknown predisposing factors that differs from the well described maxillary cheek teeth infundibular caries. Advanced PC can lead to premature wear and fracture of cheek teeth and thus is of welfare importance. Recent studies have shown large variation in the prevalence of PC in different European countries, with a trend towards a greatly increasing prevalence. One hundred and one equine heads sourced from a Scottish rendering plant were examined for the presence and grade of PC using the modified Honma equine dental caries grading system. The presence of cheek teeth calculus, diastemata and fractures was also recorded. Peripheral caries was present in 91% of horses; only affected the cheek teeth and was predominantly (72.6%) Grade 1 Class 1 (localised pitting lesions only affecting cementum). The caudal three cheek teeth were more commonly affected (74.7% prevalence) as compared to the rostral three cheek teeth (32.1% prevalence). The palatal aspect of maxillary and the buccal aspect of mandibular cheek teeth were significantly (245% and 170%, respectively) more commonly affected by PC than the opposite sides. Female horses were more commonly affected than males. Because post-mortem examination allows the most detailed oral examination to be performed, this may partly explain the higher PC prevalence found in the current, as compared to previous studies, in addition to the particular population examined in this study.     

Transmaxillary anchored silicon embedded gauze plug in the post-operative treatment of a large oromaxillary fistula caused by a supernumerary cheek tooth

A 9-year-old Hungarian sport horse gelding was presented to the clinic in poor condition displaying malodorous bilateral purulent nasal discharge. Oral examination revealed the presence of supernumerary 111 and 211. Bilateral diastema formation between the third maxillary molars and the supernumerary teeth with deep periodontal pockets and massive food impactions were diagnosed endoscopically. Radiography revealed inhomogenous sinus opacities in the left and right paranasal sinuses. Following bilateral oral extractions of the supernumerary cheek teeth and third maxillary molars, bilateral oromaxillary fistula formations were diagnosed (about 17 mm diameter on the right side). Bilateral frontal and right-sided maxillary trephinations and resection of the right bulla of the maxillary septum were performed. Massive food impactions of the left and right paranasal sinuses were removed under endoscopic control. Repeated trans-endoscopic sinus lavage was performed post-operatively. After 2.5 months, the large right-sided oromaxillary communication was temporarily closed with a transmaxillary anchored, gauze-cored silicon plug on an outpatient basis. Follow-up examination after 187 days revealed complete closure of the oromaxillary fistula and absence of sinusitis. In a 1.5-year follow-up control, no pathological conditions were found.     

Bone marrow lesions of the distal condyles of the third metacarpal bone are common and not always related to lameness in sports and pleasure horses

The metacarpophalangeal joint is a common site of pain in horses. Little information is available about bone marrow lesions in the distal condyles of the third metacarpal bone in sports and pleasure horses. Aims of this prospective, retrospective, observational study were to evaluate the prevalence of bone marrow lesions in the distal condyles of the third metacarpal bone, to describe their anatomic distribution and to correlate lesions with the presence of lameness and the level and type of activity. All sports and pleasure horses undergoing standing low‐field MRI of the front fetlock region between 2009 and 2016 were included and divided into three lameness groups according to the results of diagnostic analgesia. Bone marrow lesions were analyzed and graded by one reader. Grades were compared between anatomical locations and between lameness groups. A total of 166 horses were sampled. The prevalence of bone marrow lesions was 76.5% (127/166). The dorsal aspects of the medial condyle (31%, 39/127) and of the sagittal ridge (28%, 36/127) were the most commonly affected locations. There was no significant difference between both forelimbs (lame limb and non‐lame limb) of the same horse. Lesion severity was neither significantly associated with the lameness group nor with the type or level of activity. The prevalence of bone marrow lesions in the distal condyles of the third metacarpal bone is high in this population and the clinical significance is not always clear. Further studies are required to elucidate the clinical significance of this finding in sports and pleasure horses.     

MAGNETIC RESONANCE IMAGING FEATURES OF EQUINE NIGROPALLIDAL ENCEPHALOMALACIA

Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed.     

ULTRASONOGRAPHY OF THE CANINE, FELINE AND EQUINE TONGUE: NORMAL FINDINGS AND CASE HISTORY REPORTS

A submental approach using a 5, 7.5 and 10 MHz mechanical sectorial transducers was used to evaluate the ultrasonographic appearance of the normal and abnormal canine, feline and equine tongue. Seven normal animals were used to characterize the in vivo normal ultrasonographic appearance of the oropharynx. Consistently seen anatomical landmarks included the lingual parenchyma, lingual artery, soft and hard palate interfaces, mandible, basihyoid bone and sublingual musculature. Seven fresh canine, feline and equine cadavers were dissected to confirm the ultrasonographic findings. Seven animals with signs of ptyalism, dysphagia, halitosis and visible lingual lesions were also studied. A foreign body and abscesses secondary to a penetrating wound were detected in a horse. Ultrasound guidance aided surgical dissection, removal of the foreign body and intraoperative drainage of the abscesses. Ultrasound provided valuable non-invasive documentation of the architecture, size and margins of six lingual neoplasms. Ultrasonographic monitoring of the response to the treatment of lingual lesions may be beneficial in the management of patients.     

ULTRASONOGRAPHY OF THE EQUINE BICIPITAL TENDON REGION: A CASE HISTORY REPORT AND REVIEW OF ANATOMY

The equine shoulder region is difficult to investigate by conventional imaging modalities. Diagnostic ultrasound has proven valuable for investigation of soft tissue injuries of the human shoulder. In a horse with shoulder lameness, the authors employed diagnostic ultrasound to augment the use of conventional radiography. A defect in the subchondral bone layer of the medial humeral tuberosity, with adjacent bony fragments were clearly identified with ultrasound. Ultrasound was used for initial evaluation of the bicipital tendon and bursa. The technique was subsequently used to follow and evaluate the post-operative condition of the proximal cranial humerus, bicipital tendon and bursa in this patient. The bicipital regions of 2 immature and 3 adult normal horses were also examined with to illustrate the normal ultrasonographic anatomy of the cranial shoulder region.