An unusual cause of colic in a neonatal foal

A case of a neonatal foal with acute colic and respiratory distress is described. The foal presented with signs of acute colic and was treated medically. The foal did not respond to treatment and 2 h after admission the foal began to demonstrate signs of respiratory distress. Thoracic and abdominal radiographs were obtained and a diagnosis of a diaphragmatic hernia was made. Surgical repair of the hernia was recommended but the owner declined and the foal was subjected to euthanasia. Post mortem findings confirmed the diagnosis and revealed that the defect was of congenital origin. Congenital diaphragmatic hernia is an unusual cause of colic in a neonatal foal.     

Surgical repair of a congenital lateral abdominal wall hernia in a neonatal foal

A 16‐hour‐old Quarter Horse filly presented for evaluation of a soft mass in the right caudoventral lateral abdominal wall. Radiography and ultrasonography confirmed the presence of a nonreducible lateral abdominal wall hernia with small intestine located between the skin and body wall. The size of the defect itself could not be imaged and the filly was taken to surgery. A 4 cm vertical defect that appeared congenital was found in the transverse abdominal muscle and was repaired by primary apposition. This case report describes the repair and outcome of this unusual type of congenital hernia.     

Successful outcome after surgical correction of large colon atresia in a colt foal

This report describes successful surgical correction and long-term survival of a case of large colon atresia in a 24-h-old Warmblood colt, referred with signs of unrelenting abdominal pain and a suspicion of meconium impaction. Radiographic and ultrasonographic examination was indicative of large colon meconium impaction with secondary ileus. Due to deterioration of the foal, surgery was recommended. An atretic segment was found between the left ventral and dorsal large (ascending) colon. A band of fibrous tissue with no identifiable lumen connected the segments. Surgical correction was done by performing a stapled side-to-side anastomosis. Twelve days after surgery, the foal was discharged. Twenty-two months after discharge, the owner reported the foal developing as expected compared with its peers, but had a mild, self-limiting episode of colic at 20 months of age.     

Congenital bilateral aplasia of the metacarpophalangeal joints in a foal

A 2‐day‐old Warmblood filly was presented for examination of an angular limb deformity of the left front limb and an upright conformation of both metacarpophalangeal joints. Radiological examination revealed bilateral absence of the metacarpophalangeal joint space with fusion of the third metacarpal bone and first phalanx (synostosis). No treatment was undertaken. The filly was readmitted to the clinic 10 weeks later for bilateral front limb lameness. On radiological examination, the synostosis of the front metacarpophalangeal joints was still present. Physitis of the distal growth plate of the right third metacarpal bone and proximal growth plate of the right proximal phalanx, and an avulsion fracture of the palmaromedial and proximal aspect of the left middle phalanx, with a cystic like lesion on the medial aspect of distal first phalanx and proximal middle phalanx were diagnosed. Given the poor prognosis, the foal was subjected to euthanasia. Post mortem examination confirmed the absence of the metacarpophalangeal joint space with a trabecular bony union between the third metacarpal bone and the first phalanx. A rudimentary joint capsule was present at the level of the absent joints as well as a small zone of articular cartilage, which invaginated over a short distance into the dorsal trabecular bone on the right front limb. On the medial aspect of the left proximal interphalangeal joint, a focal defect of articular cartilage with exposure of subchondral bone was observed. This is the first case report of a foal born with congenital aplasia of both metacarpophalangeal joints. Congenital malformations should be considered as differential diagnosis in lame foals or foals born with angular or flexural limb deformities.     

Hydranencephaly in a foal

Hydranencephaly is well recognised in several domestic animals, especially ruminants, but is virtually unknown in the horse. This case report describes a premature filly foal that on the day of delivery was found with a severe neurological disorder that initially improved but then progressively worsened. The foal was subjected to euthanasia on humane grounds and post mortem examination revealed somewhat asymmetric but bilateral destruction of the telencephalon identified as hydranencephaly. The possible causes of hydranencephaly in foals are discussed.     

Imaging diagnosis and clinical presentation of a Chiari malformation in a Thoroughbred foal

A newborn Thoroughbred foal was presented to the clinic with ambiguous neurological deficits, spinal anomalies and a soft tissue swelling dorsal to the lumbar vertebral column. The foal was alert but unable to rise and stand. With radiography, ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI) a lumbar dysraphic anomaly, cerebellar herniation and coincidental skeletal abnormalities were documented. Finally, a meningomyelocele was defined and, in context with the cerebellar herniation through the foramen magnum, the foal was diagnosed to have a Chiari malformation. The MRI examination corresponded best with the post mortem findings. Although 3‐dimensional imaging methods have been considered superior regarding full and detailed assessment of the congenital malformation, radiography and ultrasonography also provide essential information to diagnose dysraphic lesions at reduced costs and efforts. A Chiari malformation should be considered as a differential diagnosis in foals with neurological deficits.     

Genetic screening of the canine zinc finger protein multitype 2 (cZFPM2) gene in dogs with tetralogy of Fallot (TOF)

A recent genetic study in humans where the ZFPM2 gene was screened for mutations revealed a heterozygous mutation that was found to contribute to several sporadic cases of tetralogy of Fallot (TOF). We hypothesized that this would also hold true for a study group of dogs with TOF. We isolated the full-length cDNA of the canine ZFPM2 and aligned the deduced amino acid sequence against sequences from other species. Our analysis indicated that the canine ZFPM2 was phylogenetically much closer to the human ZFPM2 compared with the mouse or rat sequences. Further gene expression analysis also failed to identify differential gene expression between affected and unaffected dogs. We screened the cZFPM2 for mutations in a group of dogs with TOF but found no significant base changes in either the splice sites or the coding regions.     

Bilateral Polydactyly in a foal

The following case report describes the diagnosis and surgery of bilateral polydactyly of unknown origin in a colt. A 7-month-old Berber colt was referred for cosmetic and curative excision of supernumerary digits. Radiographic examination revealed bilateral polydactyly and well-developed first carpal bones. Surgery consisted of an osteotomy of both second metacarpal bones combined with an amputation of the supernumerary digits. The follow-up at 18 months after surgery revealed a sound horse with an excellent cosmetic outcome.     

Bullous emphysema with haemorrhage in a premature foal

A Warmblood foal was admitted at one day of age because of prematurity and seizures. Clinical and clinical pathology abnormalities were consistent with prematurity and suspected hypoxic seizures that responded to anti‐convulsive therapy. The foal stabilised after several days of intensive care but then developed an airway infection. Thoracic radiographs showed multiple cavitary lesions and ultrasound examination suggested intra‐cavital haemorrhage. The foal went on to develop septicaemia and was subjected to euthanasia. Post mortem examination revealed multiple bullous emphysema with haemorrhage. This disorder should be considered in the differential diagnosis of foals having air‐fluid filled cavities on thoracic radiographs.     

Traumatic sacral fracture following dystocia in a Thoroughbred foal

A Thoroughbred colt with a history of dystocia was referred for further management of suspected hypoxia. The foal showed signs of neonatal maladjustment syndrome and hindlimb paralysis. Radiography revealed the presence of a severe lumbosacral injury. The foal was subjected to euthanasia due to a hopeless prognosis. Computed tomography was performed post‐mortem and revealed a type I Salter Harris fracture of the cranial physis of the first sacral vertebra.     

Tetralogy of Fallot in a Young Ferret (Mustela putorius furo)

A 17-month-old albino, castrated male domestic ferret (Mustela putorius furo) was presented for evaluation of a heart murmur. The murmur was first auscultated when the ferret was 12 weeks of age, coinciding with its first known evaluation by a veterinarian. At the time of diagnosis, the ferret was reported to have mild exercise intolerance. The clinical findings on the ferret were within normal limits other than a right parasternal systolic murmur (grade 4/6) that radiated to the left parasternal region. The ferret was not receiving any medications. All 4 features of tetralogy of Fallot (TOF) were identified with echocardiography. Thoracic radiographs were suggestive of TOF with mild right-sided enlargement of the cardiac silhouette and small pulmonary vasculature. A serum biochemistry profile and complete blood count were within the reference ranges for domestic ferrets. At that time atenolol (3.25 mg, every 24 hours, orally) was prescribed to treat the clinical condition of the animal. At a 1-week follow-up examination, the patient's heart rate had decreased from 240-300 beats per minute to 180-260 beats per minute. The owner reported that the ferret was sleeping more frequently during the first week of therapy but had normal activity when awake. At a 5-month recheck examination, the patient was reported to be completely normal at home. This is the first case report of TOF in a ferret.     

Splenic rupture and splenectomy in a foal

A 45‐day‐old foal was presented for abdominal pain. Examination revealed the presence of haemoabdomen. An exploratory celiotomy was performed that revealed a large tear on the visceral surface of the spleen. A splenectomy was performed without rib resection. An abdominal wall hernia and leucocytosis had developed by 6 weeks post surgery. A second celiotomy to repair the hernia and explore the cause of the leucocytosis was performed 10 weeks after the first surgery. A portion of the caecum and colon had become adhered to the body wall at the site of the hernia; these areas were resected and the hernia repaired with a polypropylene mesh. The filly made a good recovery and is currently in training. Splenic rupture should be considered in any horse showing signs of abdominal pain with ultrasonographic findings consistent with haemoabdomen.     

Primary malignant melanoma in the oesophagus of a foal

A 2‐month‐old filly was evaluated for severe colic. Ultrasound, abdominocentesis and physical examination findings prompted an abdominal exploratory surgery. Perforation of the stomach was discovered during the surgery. The filly was humanely subjected to euthanasia under anaesthesia and post mortem examination was performed. In addition to gastric and duodenal ulceration, a thickened, black area of the proximal oesophagus was discovered. Histopathology of the lesion revealed primary malignant melanoma. Although rare, primary melanoma can occur in noncutaneous locations.     

Complex stifle injury in a foal

A 130 kg, 60-day-old Quarter Horse male foal presented with bilateral stifle effusion and severe left hindlimb lameness. Clinical examination and imaging including radiography, ultrasound and computed tomography revealed bilateral stifle trauma. Specifically, disruption of the left medial meniscus and deep bone injury to the left medial femoral condyle (MFC) were detected, and bilateral injury to the origin of the cranial cruciate ligaments was suspected. Treatment consisted of stall rest and joint injection with corticosteroids, however there was little improvement in lameness. Due to the poor prognosis for soundness, the foal was subject to euthanasia 10 weeks after initial presentation. Post-mortem examination supported the left medial meniscus and MFC injuries and revealed avulsions of the origin of the cranial cruciate ligaments (complete on the left and partial on the right) from the lateral femoral condyle. Histopathology of the left stifle joint revealed varying depths of MFC osteochondral injury and severe left medial meniscus damage.     

Severe hyperkalaemia associated with renal dysplasia in a 2-day-old foal

A 2-day-old filly foal presented with signs of depression, recumbency and inappetence. Blood analyses revealed hypoalbuminaemia, hyperfibrinogenaemia, hyperglycaemia and hyperkalaemia. The foal deteriorated despite intensive treatment and was subjected to euthanasia. At post mortem examination, the urinary bladder, ureters and kidneys appeared normal grossly. Histologically both kidneys showed disorganised development with the presence of structures inappropriate for a foal of this age, including primitive glomeruli, immature renal tubules and persistent metanephric ducts. Based on these findings a diagnosis of bilateral renal dysplasia was made.     

Nutritional management of the foal with diarrhoea

Diarrhoea is a common problem in the neonatal and suckling foal. In certain circumstances supplemental nutrition is necessary depending on the age of foal, severity of diarrhoea and presence of other systemic manifestations. Nutritional supplementation can be provided either enterally or parenterally. Enteral nutrition is superior to parenteral nutrition because it is the most natural and physiologically sound means to provide nutritional support. Parenteral nutrition may be warranted if the foal is unable to receive or tolerate enteral nutrition. Dextrose alone or with amino acids and lipids can provide appropriate nutrition when enteral feeding is not tolerated. As soon as the foal stabilises enteral feeding can be reintroduced.     

Osteomyelitis of the scapulohumeral joint associated with Rhodococcus equi and unresponsive to antibiotherapy in a foal

This case report describes the treatment and outcome of a 3.5-month-old lame foal, with a history of pneumonia associated with Rhodococcus equi. Clinical examination identified osteomyelitis of the scapulohumeral joint. The unusual location of the Rhodococcus equi osteomyelitis unresponsive to prevention and adequate treatment led to euthanasia of the patient. Post-mortem findings confirmed bronchopneumonia due to Rhodococcus equi as well as the osteomyelitis of the scapulohumeral joint. This case highlights that Rhodococcus equi should be considered as a pathogen in extrapulmonary locations such as septic arthritis and osteomyelitis in foals with history of bronchopneumonia. Early and aggressive treatment should be considered.     

Paratracheal air cyst in a foal

A 1-day-old American Paint Horse was presented for a large air-filled mass along the ventral aspect of the neck. Bronchoscopy and oesophagoscopy revealed no sign of communication with the trachea or oesophagus. Radiographs and a computed tomography scan of the neck identified a communicating tract between the lumen of the cystic mass and mid-trachea. The foal was systemically healthy at this initial presentation, and delayed removal of the cyst was recommended to allow further maturation of the foal prior to undergoing general anaesthesia. Upon discharge, the cyst continued to grow in size and became more fluid than air-filled requiring repeat centesis and draining. The foal was then re-presented at 3 weeks of age for surgical removal. In surgery, direct communication with the trachea was identified and ligated. Histopathology demonstrated that the cyst lining was composed of squamous epithelium with goblet cells and occasional ciliated cells. The location, morphological features and congenital presentation of the mass were consistent with a paratracheal air cyst (PAC). Surgical resection resulted in excellent functional and cosmetic outcome. Although not previously reported in horses, PAC should be included in the differential diagnosis of an air-filled ventral neck mass in equine neonates. Complete surgical excision may result in a successful outcome.