Subscapular lymph node abscessation as a result of metastatic Streptococcus equi subspecies equi infection: An atypical presentation of bastard strangles in a mare

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

Standing removal of the proximal aspect of an olecranon fracture in a mature horse

A 12‐year‐old 450 kg Argentine polo mare presented with a dropped elbow and an unwillingness to bear weight after being kicked by another horse on the lateral aspect of the upper left forelimb. The mare was subsequently diagnosed with a displaced olecranon fracture that did not readily conform to the standard classification systems. Referral for surgical treatment involving open reduction and internal fixation was declined due to financial constraints. Due to the mare being unsuitable for breeding, and conservative treatment of displaced olecranon fractures being deemed to have an overall poor prognosis for return to full athletic performance, another treatment option was sought. Given the fracture configuration, standing surgical removal of the large proximal fragment was performed. The mare returned to full athletic performance 12 months post operatively without lameness. This case report describes an alternative treatment option for selected olecranon fractures.     

Penetrating injury at the thoracic inlet in a Paint‐Arab mare

A 12‐year‐old Paint‐Arab mare was admitted for evaluation of a penetrating chest laceration at the thoracic inlet. The left brachiocephalic muscle was transected and the recurrent laryngeal nerve was traumatised. Subsequent to the injury, the horse developed Horner's syndrome on the left side of the neck and face, Grade IV left laryngeal hemiplegia, dysphagia, cough and subcutaneous emphysema. The defect was closed in multiple layers. Antimicrobial and antiinflammatory therapy was instituted along with local wound care. The mare remained bright and responsive and the wound healed normally. The mare showed no signs of respiratory distress. Dysphagia and ptosis persisted at 30 days post trauma.     

Diagnostic imaging,surgical treatment and histopathological findings of a vascular hamartoma in a 2‐year‐old horse

We describe a case of a 2‐year‐old mare that presented with a large firm swelling on the lateral aspect of the right tarsus. Diagnostic ultrasound demonstrated a fluid filled cavernous mass that was not clearly demarcated from the surrounding subcutaneous tissue. Contrast radiography with intralesional injection of contrast medium showed accumulation of the medium in the caverns of the mass and in the saphenous vein. Contrast enhanced computed tomography demonstrated 2 vascular meshes, one deep and one more superficially, closely associated with the mass. Surgical excision of the mass was performed and a vascular hamartoma was diagnosed based on histopathology. The horse showed no signs of recurrence 7 months after surgery.     

An atypical case of recurrent cellulitis/lymphangitis in a Dutch Warmblood horse treated by surgical intervention

The case reported here describes an atypical presentation of cellulitis/lymphangitis in an 8‐year‐old Dutch Warmblood mare. The horse was presented with a history of recurrent episodes of cellulitis/lymphangitis and the presence of fluctuating cyst‐like lesions on the left hindlimb. These lesions appeared to be interconnected lymphangiectasias. Surgical debridement followed by primary wound closure and local drainage was performed under general anaesthesia. Twelve months post surgery, no recurrence of cellulitis/lymphangitis had occurred and the mare had returned to her former use as a dressage horse.     

Bad behavior or a physical problem? Rearing in a Dutch Warmblood mare

Behavior problems in horses are often thought to be due to the horse’s bad attitude, which commonly results in them being punished. However, when these cases are carefully worked up, there may be an underlying physical problem, and pain may play an important role. A 5-year-old Dutch Warmblood mare was presented for rearing and flipping over backward. The mare had been repeatedly examined by an equine veterinarian and a nonveterinarian equine dentist who found no abnormalities. Several different bits were tried, and side reins were used to keep her head down. The mare was whipped every time she reared. None of these measures helped. On presentation to our equine teaching hospital, no abnormalities were detected on routine physical examination. The behavior was observed when the mare was lunged; as soon as a small amount of tension was put on the lunge rein, the mare shook her head horizontally for approximately 1-2 seconds, reared, and flipped over onto her back. Neurological examination revealed that the mare was slow to resume a normal stance when her hind legs were placed in an abnormal position. Dental examination and endoscopy of the upper airways proved unremarkable. Radiography of the atlanto-occipital joint area revealed fractures of the first and second cervical vertebrae and fracture fragments, which are both suggestive for the presence of cervical instability and the possible presence of spinal cord compression. These suggestions were further supported by identification of delayed postural reflexes during neurological examination. The mare was deemed unfit for dressage and was successfully kept for breeding. Horses are frequently punished for “bad behavior.” These behaviors are frequently due to underlying physical problems and not a “nasty” horse. This case highlights the importance of careful history taking and a thorough veterinary examination with the use of further diagnostics (if necessary) when dealing with equine behavior problems.     

Arthroscopic treatment for cervical articular process joint osteochondrosis in a Thoroughbred horse

A yearling Thoroughbred colt was presented for investigation of neck stiffness and episodes of intermittent neck pain without neurological signs. Osteochondrosis (OCD) of the cervical articular process joints (APJs) was diagnosed with the aid of radiography and computed tomography. An articular osteochondral fragment of the left fourth caudal cervical articular process was removed arthroscopically following a cut down approach to the joint capsule of the affected APJ. Surgical removal resulted in resolution of clinical signs at 4 weeks. However, subsequently the horse was markedly ataxic 6 weeks post surgery after being found cast in its stable. Cervical stenotic myelopathy was considered the most likely cause based on clinical and radiographic signs and the horse was subjected to euthanasia due to a poor prognosis for racing. Post‐mortem examination identified atypical cartilage within several cervical APJs with histological changes consistent with OCD. This case report supports OCD of the APJs as a cause of neck pain and confirms the clinical practicality and short‐term effectiveness of arthroscopic fragment removal. Surgical treatment for cervical OCD should be considered in horses without neurological signs, although case selection is important and the underlying pathology remains a risk factor for the development of subsequent neurological signs.     

Successful treatment of traumatic oesophageal rupture with severe cellulitis in a mare

A five-year-old standardbred mare suffered a cervical oesophageal rupture subsequent to a kick. Marked cellulitis and extensive soft tissue damage resulted. Treatment consisted of creating an oesophageal fistula, local debridement and systemic antibiotics. The mare made a long but successful recovery. Treatment of oesophageal rupture in the horse is discussed.     

Acquired peri-articular ganglion cyst in the lateral femorotibial joint in an 18-year-old Percheron cross mare

This report describes a case of sudden lameness in an 18-year-old Percheron cross mare after presumably being kicked by another horse, and the subsequent formation of a ganglion cyst originating from the lateral femorotibial joint. Physical examination, radiographic and ultrasonographic investigation identified a soft round 5 cm diameter mass attached to the left lateral femorotibial joint. After surgical removal, histopathological examination confirmed a ganglion cyst. The horse responded well to the surgical removal of the cyst, and 4 weeks after the surgery, the mare has returned back to her same athletic performance. According to the authors’ knowledge, this is the first reported case that describes a peri-articular ganglion cyst originating from the stifle joint.     

Pseudomonas aeruginosa sepsis in an adult horse with enteric Salmonellosis

Objective: To report a case of enteric Salmonellosis and Pseudomonas aeruginosa bacteremia in an adult horse. Case summary: A 7‐year‐old mare presented for signs of acute abdominal pain. Exploratory laparotomy allowed surgical correction of right dorsal displacement of the large colon with a 180° volvulus at the cecocolic ligament. Postoperatively, the mare developed fevers, leukopenia, and diarrhea. Salmonella newport was cultured from the feces and P. aeruginosa from 2 consecutive blood cultures. The mare responded well to intensive medical therapy. New or unique information provided: Bacteremia associated with colitis is unusual in an adult horse, although the percentage of animals that may be bacteremic is unknown. The bacteria isolated, P. aeruginosa, a common pathogen of other sites in the horse, has not, to our knowledge, been previously reported as a cause of bacteremia and septicemia in an adult horse.     

Treatment using cannabidiol in a horse with mechanical allodynia

A 4-year-old Quarter Horse mare was seen in the field by Colorado State University's Equine Sports Medicine Service for a 5-week history of marked sensitivity to touch near the withers/shoulder region. On examination, the mare showed a marked adverse response to light touch over the caudal neck and withers region. Diagnostic imaging of the caudal neck, withers and shoulder region showed no significant abnormalities. Vital parameters, complete blood count and chemistry profile were also within normal limits, as was a reproductive ultrasound examination. The mare received dexamethasone, gabapentin, magnesium/vitamin E, prednisolone and aquapuncture with no improvement in clinical signs. The mare was then started on pure crystalline cannabidiol (250 mg by mouth twice daily), which resolved the clinical signs after 2 days.     

Ataxia and weakness as uncommon primary manifestations of hepatic encephalopathy in a 15‐year‐old trotter gelding

A 15‐year‐old trotter gelding was evaluated because of an acute onset of ataxia in all 4 limbs. There was no known history of trauma. The gelding showed grade 2/5 ataxia in all 4 limbs, which was localised after clinical neurological examination to the cervical vertebral spinal cord. Initial therapy consisted of oral anti‐inflammatory doses of prednisolone and antimicrobial treatment with potentiated sulphonamides. The ataxia progressed to grade 3/5 at Day 10 of hospitalisation. Additionally, the horse was slightly depressed and showed spontaneous yawning during examination. Facial sensation was blunted. Blood chemistry revealed a marked elevation of liver specific enzymes and blood ammonia levels. Transcutaneous abdominal ultrasonography revealed hepatomegaly. Due to a guarded prognosis, the horse was subjected to euthanasia. At necropsy the left lateral liver lobe was markedly enlarged and showed a firm texture, whereas the cranial part and the right and quadratic liver lobe displayed a severe and diffuse atrophy. Histopathologically, the left lateral liver lobe revealed a moderate to severe cirrhosis with a severe, diffuse hepatocellular iron‐accumulation. Increased numbers of Alzheimer type II astrocytes in the cerebral cortex and cerebral white matter vacuolisation were indicative for encephalopathy. These findings were interpreted as haemosiderosis and cirrhosis of the liver with consecutive hepatic encephalopathy. Aetiologically, haemosiderosis should be considered as a cause of liver cirrhosis with consecutive hepatic encephalopathy. Although hepatic encephalopathy in horses usually presents with predominating cerebral signs, it has to be taken into account as a differential diagnosis in cases of acute onset generalised ataxia.     

Episcleral cyclosporine A implants for the management of unilateral keratoconjunctivitis sicca in an 8‐year‐old mare

An 8‐year‐old mare was presented for investigation of a 1‐month history of blepharospasm, eyelid swelling, corneal edema, and ocular discharge of the right eye (OD). Ophthalmic examination confirmed mucopurulent ocular discharge, conjunctival hyperemia, and a dry, dull appearance to the cornea OD. Schirmer tear test results confirmed an absence of tear production OD (0 mm/min) consistent with keratoconjunctivitis sicca. Treatment with topical 0.2% cyclosporine A resulted in an improvement in clinical signs. An episcleral cyclosporine A implant was placed under standing sedation 5 days after initial presentation. Re‐examination 9 days post‐operatively confirmed that the mare's tear production in the right eye had improved and no further clinical signs had been observed. Topical medications were gradually discontinued. Re‐examinations performed up to 12 months postsurgery showed no recurrence of clinical signs and no adverse effects of the implant. To our knowledge, this is the first report of the use of a cyclosporine A implant in the management of KCS in a horse and highlights its potential as an effective, alternative therapy in the management of KCS in horses.     

Ascites in a 13‐year‐old miniature horse mare with an ovarian granulosa theca‐cell tumour: A manifestation of Meigs' syndrome?

A 13‐year‐old miniature horse mare presented for evaluation of ascites. Abdominal ultrasound showed severe free peritoneal fluid accumulation as well as a caudal abdominal mass. The peritoneal fluid was characterised as a transudate with no evidence of sepsis. Surgical exploration of the abdomen was performed; copious free peritoneal fluid and a large right ovarian mass were discovered. The abnormal ovary was removed, and the mass was determined histologically to be a benign granulosa theca‐cell tumour. Although there was mild peritoneal fluid accumulation in the immediate post operative period, the ascites effectively resolved with removal of the tumour, and the mare returned to a normal lifestyle. This is similar to reports of Meigs' syndrome in human women, in which a benign ovarian mass of significant size causes ascites that resolves once the mass is removed.     

Gabapentin for the treatment of neuropathic pain in a pregnant horse

CASE DESCRIPTION: A 24-year-old 732-kg (1,610-lb) pregnant Belgian draft horse mare developed neuropathy and signs of intractable pain following colic surgery. CLINICAL FINDINGS: Following recovery from colic surgery to treat compression of the small and large intestines because of a large fetus, the mare was noticed to have signs of femoral neuropathy involving the left hind limb. Within 36 hours after recovery, the mare developed signs of severe pain that were unresponsive to conventional treatment. No gastrointestinal tract or muscular abnormalities were found, and the discomfort was attributed to neuropathic pain. TREATMENT AND OUTCOME: The mare was treated with gabapentin (2.5 mg/kg [1.1 mg/lb], PO, q 12 h). Shortly after this treatment was initiated, the mare appeared comfortable and no longer had signs of pain. Treatment was continued for 6 days, during which the dosage was progressively decreased, and the mare was discharged. The mare subsequently delivered a healthy foal. CLINICAL RELEVANCE: Gabapentin appeared to be a safe, effective, and economical treatment for neuropathic pain in this horse.     

Evaluation of four topical preparations for the treatment of cannon hyperkeratosis in a horse

The response to treatment with four topical preparations was evaluated in an 11‐year‐old Morgan horse mare with histologically confirmed quadrilateral cannon hyperkeratosis. Each limb was treated for 30 days with 0.1% tacrolimus ointment, 0.1% adapalene gel, 0.2% phytosphingosine spray or a water‐based emollient. Response to treatment was evaluated both histologically and visually. A water‐based emollient and 0.1% tacrolimus ointment produced encouraging clinical responses. Pre‐treatment histopathology identified marked, mostly compact, hyperkeratosis and follicular hyperkeratosis, most prominent in the infundibular area. Following treatment, histopathology identified a mild reduction in follicular keratin production and stratum corneum thickness.     

Internal fixation of a fractured axis in an adult horse

Objective: To report internal fixation of a fractured axis with a dynamic compression plate (DCP). Study Design: Case report. Animals: A 7‐year‐old Warmblood gelding. Method: Surgery was performed under anesthesia in sternal recumbency. After fracture reduction the complete transverse fracture in the cranial third of the axis was stabilized with a 7‐hole 4.5 mm DCP. Optimal positioning of the plate and the length of the screws were facilitated by fluoroscopy. Recovery from anesthesia was supervised in a pool. Results: The horse had an excellent outcome and returned to its previous activity level. Conclusion: Surgical treatment with fracture reduction and plate fixation enables normal bearing of the head and neck and improves neck flexibility soon after surgery.     

ECHOCARDIOGRAPHIC DETECTION OF A DISSECTING AORTIC ROOT ANEURYSM IN A THOROUGHBRED STALLION

A 12-year-old Thoroughbred stallion was referred with a history of acute pain and tachycardia immediately after breeding a mare. On presentation, the horse showed no evidence of pain and routine examination of the abdomen failed to yield any abnormalities, however, a persistent tachycardia remained. A base-apex ECG examination revealed sustained ventricular tachycardia which resolved spontaneously within 12 hours of hospitalization. During this period, the stallion developed a grade 4/6 heart murmur. An aortic root aneurysm in the right sinus of Valsalva was diagnosed using two-dimensional echocardiography. Pulsed-wave Doppler evaluation revealed turbulent flow within the aneurysm. Repeat echocardiographic examination 10 months after the onset of signs revealed no change and the horse continues to perform as a breeding stallion.