Haemangiosarcoma in the horse

Neoplasms arising from vascular endothelial cells include benign haemangioma and malignant haemangiosarcoma, both of which are rare in the horse. Haemangiosarcoma can arise as a solitary mass, typically involving the eye or skin, or as disseminated tumours throughout multiple organs. There is no sex, breed or age predilection but most cases are found in middle aged horses. Clinical presentations of haemangiosarcoma in the horse include the presence of a visible mass or reflect dysfunction of the organ involved, thus making it difficult to differentiate from other neoplasms. Ante mortem diagnosis through clinicopathological findings, cytological findings of body cavity effusions or fine needle aspirates are often unrewarding. Biopsy or mass submission for histopathological examination may aid in diagnosis of haemangiosarcoma. A majority of cases are diagnosed post mortem; however, if the mass is poorly differentiated additional diagnostics such as immunohistochemical staining may be needed. Unfortunately, treatment of haemangiosarcoma is often unrewarding and limited based on the location of the mass and the aggressive nature of this neoplasm.     

Ante mortem diagnosis of necrotising emphysematous oesophagitis and gastritis in a horse

The case reported here describes a rare presentation of necrotising, emphysematous oesophagitis and gastritis in a horse presenting for signs of anorexia, dysphagia and ptyalism. Radiography of the retropharyngeal region revealed intramural gas within the cranial oesophagus. Further diagnostic evaluation supported an ante mortem diagnosis of emphysematous oesophagitis with concurrent septic pleuritis and peritonitis. Post mortem findings confirmed an emphysematous, necrotising oesophagitis and gastritis with a Clostridium sp. transmural infection. To our knowledge, this case describes the first recorded ante mortem diagnosis of emphysematous oesophagitis with concurrent gastritis in the horse.     

Carcinoma of an accessory genital gland in a 23‐year‐old Camargue gelding

This report describes the case management, histopathological and post mortem findings in a 23‐year‐old gelding with a peri‐rectal mass. The mass was debulked surgically and submitted samples revealed it to be a poorly differentiated carcinoma. In the post operative period the horse developed signs of abdominal pain and dysuria and was subjected to euthanasia. Post mortem examination revealed a large infiltrative mass located between the rectum and urethra, consistent with a carcinoma of an accessory genital gland, most likely the seminal vesicle.     

Aortic rupture and aorto‐pulmonary fistulation in the Friesian horse: Characterisation of the clinical and gross post mortem findings in 24 cases

Reasons for performing study: In horses, aortic sinus of Valsalva aneurysms or tears in the aortic root are well‐recognised conditions in breeding stallions, often leading to sudden death. A more uncommon form of aortic rupture, located proximal to the ligamentum arteriosum has been reported in 3 Friesian horses. Objectives: The purpose of this study was to phenotypically characterise aortic rupture and aorto‐pulmonary fistulation in Friesian horses in terms of clinical and post mortem data based on 24 cases. Methods: Friesian horses that were diagnosed with aortic rupture and aorto‐pulmonary fistulation over a period of 13 years (1997–2010) at the Department of Equine Sciences of Utrecht University (n = 15) and Wolvega Equine Hospital (n = 9), were included in this study. Case history, results of clinical examination and gross post mortem findings were screened and analysed. Results: Some cases were found dead without prior symptoms, but in several cases signs such as recurrent colic, peripheral oedema and sustained tachycardia were present for several weeks prior to cardiac failure. Clinical examination during hospitalisation revealed increased rectal temperature, peripheral oedema and increased jugular pulse with a bounding arterial pulse. In the majority of horses an aortic rupture of the aortic arch near the ligamentum arteriosum, concurrent with a circumferential cuff of perivascular haemorrhage and aorto‐pulmonary fistulation, was found at post mortem examination. Conclusions: Aorto‐pulmonary fistulation in conjunction with aortic rupture is more common in Friesians than previously estimated. In some cases findings demonstrate a progressive pathology rather than acute cardiac failure and sudden death. An appropriate approach is necessary during post mortem examination of the heart in order not to overlook the diagnosis. Potential relevance: Equine practitioners should realise that in Friesian horses presented with a history of recurrent false colic, coughing, sustained tachycardia and/or peripheral oedema, aortic rupture and aorto‐pulmonary fistulation should be included in the differential diagnosis.     

Diagnosis of lumbosacral intervertebral disc disease and protrusion in a horse using ultrasonographic evaluation and computed tomography

This case report describes the clinical presentation, diagnostic imaging modalities, treatment and post mortem evaluation of lumbosacral intervertebral disc protrusion in a mature Quarter Horse gelding 10 days after initial signs were noted. Grade 3 hindlimb ataxia, conscious proprioceptive deficits, urinary and faecal incontinence were present, which did not improve with anti‐inflammatories, antimicrobial therapy, corticosteroids, antioxidant therapy, cold‐laser therapy or electroacupuncture. Imaging modalities utilised ante mortem were computed radiography, transcutaneous and transrectal ultrasonography. Transrectal ultrasonography yielded findings highly suggestive of lumbosacral intervertebral disc protrusion and due to the lack of improvement and a poor prognosis, the horse was humanely subjected to euthanasia. Post mortem computed tomography, necropsy and histopathological evaluation confirmed lumbosacral intervertebral disc disease and protrusion into the spinal canal with subsequent impingement of the spinal nerve roots. Lumbosacral intervertebral disc protrusion as a clinical disease in the horse has not been previously described and should be included as a differential diagnosis in cases with acute hindlimb ataxia, proprioceptive deficits, and urinary and faecal incontinence.     

Effect of early filleting on the texture of breast muscle of broilers stunned with argon‐induced anoxia

1. Eighty broilers were stunned in batches of 10 with less than 1 % oxygen (air displaced by argon) and their chilled breasts were filleted at 2, 3, 5 or 21 h (argon control) post‐mortem. Twenty broilers were electrically stunned and their breasts filleted at 21 h post‐mortem (electrical control).

2. Meat quality variables studied included pH of the pectoralis major muscle measured at 20 min post‐mortem and at filleting, and texture at 24 h post‐mortem.

3. Argon stunning resulted in a rapid early post‐mortem pH fall, but there was no indication of heat toughening in the breast muscles.

4. Filleting at 2 h post‐mortem, after argon stunning, resulted in 5% of the p. major muscles having greater than 4 kg yield force (slightly tough).

5. Although post‐mortem ageing of argon stunned broilers improved the texture of breast muscle, it is inferred that filleting at 2 h postmortem resulted in breast muscle with acceptable texture.     

Evaluation of the efficacy of oxfendazole against larval and adult Toxocara canis in unweaned dogs

The efficacy of oxfendazole given at a dose-rate of 10 mg kg^-1 for 3 consecutive days against adult and larval Toxocara canis was determined in four litters of naturally infected unweaned greyhound pups. Comparison of the worm-burdens of four pups treated on days 30–32 post partum with four matched litter-mate untreated controls gave an apparent efficacy value of 98-5 per cent, the numbers of adult T. canis at post mortem examination being 3 and 202, respectively. A similar comparison involving 10 pups treated on the 5th to 7th days of life, when the T. canis would have been in various stages of larval development, gave an overall efficacy value of 75.8 per cent, with worm-counts of 1,325 and 321 for control and treatment groups. However, a greater reduction (84.1–91.7 per cent) was observed in worms achieving a length of 40 mm by the time of post mortem examination (Day 21 post partum) than in shorter worms. In the latter case, no demonstrable anthelmintic activity was detected.     

Pulmonary and hepatic eosinophilic granulomas and epistaxis in a horse suggestive of multi‐systemic eosinophilic epitheliotropic disease

Multi‐systemic eosinophilic epitheliotropic disease (MEED) is a relatively uncommon disease characterised by eosinophilic infiltration of more than one organ system, with the skin and gastrointestinal tract most commonly affected. This case report describes a gelding that presented for weight loss, increased respiratory rate and effort and chronic intermittent epistaxis. During post mortem examination diffuse eosinophilic granulomatous lesions were identified in the lung and liver, leading to a diagnosis of MEED. Veno‐occlusive pulmonary remodelling was also discovered, believed to be the cause of the chronic epistaxis and a result of the pulmonary fibrosis and eosinophilic granulomas.     

Spontaneous oesophageal perforation secondary to idiopathic muscular hypertrophy of the oesophagus

Idiopathic muscular hypertrophy of the oesophagus (IMHO) is reported in equids as an incidental post mortem finding, infrequently associated with clinical signs of oesophageal dysfunction or additional oesophageal abnormalities. Clinicopathological and post mortem findings are presented from a 15‐year‐old gelding that developed a spontaneous perforation of the distal, intrathoracic oesophagus, in association with IMHO. The majority of oesophageal perforations documented in the equine literature have been related to external or iatrogenic trauma resulting in rupture of the cervical portion of the oesophagus. In this case, the early presenting features included pyrexia and inappetance, and progressed over a 4 day period to include signs of tachypnoea, tachycardia and endotoxaemia due to the development of a fatal septic pleuritis and pleural effusion. Oesophageal obstruction was not a presenting feature. Diagnostic investigation in cases of unexplained septic pleural effusion should include oesophageal endoscopic evaluation to rule out perforation of the intrathoracic oesophagus. IMHO may represent a clinically significant, primary disease entity with the potential to lead to oesophageal perforation.     

Severe bilateral physitis with instability and Salter‐Harris type 1 fractures in two foals

This Case Report describes the clinical, radiographic, computed tomographic and post mortem findings in 2 foals with severe bilateral physitis of the distal third metatarsal bones (MtIII). The foals were admitted because of bilateral hindlimb lameness of several weeks' duration. Initial examination revealed that the physeal regions of the distal MtIII were enlarged, warmer than normal and painful on palpation. Case 1 was treated conservatively and discharged but was readmitted 8 weeks later because of clinical deterioration. In both foals, radiographs showed plantar dislocation of both epiphyses through the physis and a Salter‐Harris type 1 fracture. The foals were subjected to euthanasia and a post mortem examination.     

Soft tissue sarcomas in the pharyngeal region of a 5‐year‐old Quarter Horse mare

This case report describes the identification of multiple soft tissue sarcomas in the pharyngeal region of a 5‐year‐old Quarter Horse mare. Diagnostic work‐up included physical examination, radiography, ultrasonography, endoscopic examination of upper airways and guttural pouch, and post mortem examination with histopathology. Humane euthanasia was indicated due to the chronicity of the condition, prognosis and financial constraints.     

Traumatic neuroma of the medial palmar nerve as a possible cause of a severe gait abnormality in a Warmblood riding horse

This paper describes the history, examination and clinical findings in a riding horse with a gait abnormality. The lesion was localised to the carpal area of one of the forelimbs, but could not be properly characterised until post mortem examination, when a diagnosis of a traumatic neuroma of the medial palmar nerve could be reached. Thus, the most plausible explanation for the gait abnormality of the horse was found in the peripheral nervous system.     

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.     

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.     

Effect of post‐mortem temperature on chicken M. pectoralis major: Muscle shortening and cooked meat tenderness

1. Muscle shortening, sarcomere lengths and pH values were measured in strips of chicken M. pectoralis major (PM) muscle incubated at different time (0 to 24 h) and temperature (0° to 40°C) combinations immediately after slaughter; their effects on cooking loss and meat tenderness determined.

2. Maximum muscle shortening of 39% and 43% occurred at 0°C and 40°C respectively. At 0°C, most shortening occurred within 90 min postmortem when the pH of the muscle ranged from 7.13 to 6.52. In contrast, at 40°C, most shortening occurred during the development of rigor mortis, between 90 and 380 min post‐mortem, when the muscle pH ranged from 6.16 to 5.89. In a similar manner, minimum sarcomere lengths of 1.38 μm were reached after 90 min at 0°C while more severe sarcomere shortening, to 0.96 μm and 0.86 μm at 30°C and 40°C respectively, was not complete until after 380 min post‐mortem. Between 5°C and 20°C, muscle shortening ranged from 25 to 34% while minimum sarcomere lengths of 1.33 μm were recorded.

3. Cooking losses increased on average from 7 to 16% between 30 and 380 min post‐mortem, with maximum losses of 19% being achieved by the end of the 24‐h incubation period.

4. At 0°C, shear force values increased from 2.94 kg/cm² to 4.34 kg/cm² between 30 and 90 min post‐mortem while the muscle pH was > 6.5. At all other temperatures, increases in shear force values were not detected until 380 min post‐mortem when the muscle pH had fallen to 5.9 and rigor mortis had set in. At all times after 380 min, however, the muscle strips incubated at 0, 5 and 40°C had lower shear values (range 3.17 to 5.49 kg/cm²) than those incubated from 10°C to 30°C (range 5.06 to 7.22 kg/cm²).

5. A significant quadratic relationship was found between the degree of shortening and subsequent cooked meat tenderness, in which peak toughness occurred at 30% shortening. This would suggest that the actual extent of muscle shortening per se has an important role to play in determining the tenderness of chicken post‐mortem. Consequently, with unrestrained chicken muscle, where extensive shortening occurred at 0°C and 40°C (i.e cold‐ and rigor shortening) the cooked meat was more tender than that subjected to intermediate post‐mortem temperature regimens.     

Disseminated alimentary mycobacteriosis in the horse: a retrospective study of nine cases

This paper summarises the clinical findings of 9 cases of disseminated alimentary mycobacteriosis in horses presented at a Finnish referral equine hospital 2009–2014. Four of 9 horses were Standardbreds and 8/9 horses were male. The median age was 2 years, ranging from 6 months to 15 years. The duration of clinical signs before admission ranged from 2 weeks to 6 months. All horses demonstrated deterioration of the clinical signs after a protracted period of the disease and were finally subjected to euthanasia after poor response to multiple medical therapies. The most common complaints on admission were weight loss and diarrhoea (9/9), pyrexia (7/9), ventral oedema (7/9), lethargy (7/9) and inappetance (6/9). The most common clinicopathological abnormalities were hypoalbuminaemia and hyperfibrinogenaemia, which were present in all horses. Rectal biopsy specimens were examined from 5/9 horses and specimens were stained with Ziehl‐Nielsen (ZN). At rectal biopsy, mild multifocal neutrophilic or mild granulomatous proctitis was recognised in all 5 horses, but the ZN stain for mycobacteria was positive in only one biopsy. A liver biopsy was taken from one horse in which hepatomegaly was observed clinically and revealed marked granulomatous hepatitis with the presence of mycobacteria. The rectal biopsy from this horse was ZN negative. At post mortem examination, chronic, multifocal to coalescing granulomatous typhlocolitis and lymphadenitis were found in all horses with the small intestine less frequently involved. At histopathological examination of post mortem samples, a ZN stain was performed and intracellular acid‐fast bacilli were identified in macrophages and multinucleated giant cells in the large intestine, liver and lymph nodes in 9/9 horses and in the small intestine in 5/9 horses. Mycobacterium avium ssp. hominissuis was isolated in 5/9 horses from post mortem samples.     

Safety of multiple,submucosal inoculations of a live attenuated strangles vaccine in pregnant mares

A live attenuated vaccine against Streptococcus equi was administered submucosally in the upper lip to 224 pregnant and healthy mares to evaluate its safety. After a primary immunisation the mares were inoculated every 3 months until foaling. As control group, 206 mares of the same breeding farm were administered the solvent of the vaccine submucosally. None of the 430 mares presented any clinical evidence of strangles and neither local nor systemic reactions to vaccination were noticed. There was no association between abortion and vaccination. Furthermore no case of S. equi infection was revealed at post mortem examinations of aborted foals.     

Diagnosis of laryngeal dysplasia in five horses using magnetic resonance imaging and ultrasonography

Reasons for performing study: Laryngeal dysplasia due to suspected maldevelopment of the fourth branchial arch has been reported previously in the horse and has been associated with rostral displacement of the palatopharyngeal arch and/or right laryngeal dysfunction. These studies all described the endoscopic and/or anatomical post mortem identification of the disease, but ultrasonography or magnetic resonance imaging (MRI) of this disease have not been described. Hypothesis: MRI and ultrasound findings accurately reflect the anatomical features of presumptive fourth branchial arch abnormality and allow accurate ante mortem diagnosis of this condition and, therefore, appropriate management. Methods: Between February 2008 and January 2009, all horses examined at Rood and Riddle Equine Hospital diagnosed with rostral displacement of the palatopharyngeal arch and/or right laryngeal dysfunction using upper airway endoscopy (n = 5) underwent ultrasonography and MRI of the laryngeal region. Results: All 5 horses that met the inclusion criteria were identified and all underwent laryngeal MRI and ultrasound examinations. Features consistent with laryngeal dysplasia, including lack of the cricothyroid articulation, dorsal extension of the thyroid cartilage lamina, and absence or hypoplasia of the cricopharyngeus muscle, were seen in all cases using both types of imaging. Conclusions and potential relevance: MRI and ultrasonography permit definitive premortem diagnosis of laryngeal dysplasia. Upper airway abnormalities identified using endoscopy can be more fully characterised using MRI and ultrasonography allowing more appropriate recommendations to be made. Preoperative imaging may also prevent inappropriate surgical intervention.     

Use of intralesional cisplatin to successfully treat distal limb haemangiosarcoma in a foal

A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy.