Double ovarian tumour in the mare: Case report

Ovarian tumours in mares represent 2.5% to 6% of the most frequent neoplasms found in the equine species, with a higher chance of benignity. This study aims to describe a case of two different tumours found in the same ovary of a mare that presented clinical signs of suppressed oestrous cycle during 5 years. After unilateral ovariectomy, the ovary was sent to the histopathology examination which determined a mixed tumour of granulosa cell and leiomyosarcoma. After treatment, the mare returned to oestrus and got pregnant in the next season.     

The use of intraluminal stents for tracheal collapse in two horses: Case management and long‐term treatment

Tracheal collapse is an uncommon clinical disorder in horses but when present can be difficult to correct. Various medical and surgical procedures to correct tracheal collapse have been described in horses with variable success. Recently, the use of an intraluminal stent has been described as a treatment for tracheal collapse in a miniature horse. The long‐term management, utilising intraluminal stents, in 2 miniature horses with tracheal collapse is presented here. In particular, various complications as a result of intraluminal stent placement are described, the most persistent being the formation of granulation tissue at various regions of the stents. Multiple methods of combating granulation tissue in this situation also are discussed.     

Quality of equine veterinary care. Part 2: Client satisfaction in equine top sports medicine in The Netherlands

The aim of this study was to evaluate systematically the quality of equine veterinary top sports medicine in The Netherlands and the degree to which the expectations in the field are met. Focus was on structure, process and outcome of care. The structure of care is generally satisfactory but there is insufficient transfer of applicable scientific knowledge to the equine community and a lack of regular checks by team vets. The process of care is hampered by the failure in communication between the veterinary and paraveterinary members of a team. For continuation of the excellent international results of Dutch riders and drivers a more collaborative approach, abandoning the often secretive character of equine medicine in relation to sport horses, is necessary.     

Surgical treatment of colic in the miniature horse: a retrospective study of 57 cases (1993-2006)

REASONS FOR PERFORMING STUDY: It has been suggested that the rate of post operative abdominal adhesions in miniature horses is higher than that for other breeds. However, few reports exist in the veterinary literature describing complications and long-term survival following surgical treatment of colic in these horses. OBJECTIVES: To determine the prevalence of surgical lesions in miniature horses with acute abdominal disease in terms of clinical signs, surgical management, post operative treatment and complications, as well as short- and long-term survival. METHODS: Medical records of 57 American Miniature Horses undergoing surgical treatment for acute abdominal pain at the Michigan State University Large Animal Veterinary Teaching Hospital 1993-2006 were evaluated for clinical information. Owners and trainers were contacted to gain information regarding long-term survival. RESULTS: The most common surgical lesion was a faecalith (38/57 cases) located primarily within the descending colon and most frequently diagnosed in horses age <6 months (19/38 cases). Short-term survival to hospital discharge for horses recovered from anaesthesia was 98% (55/56) with the most common post operative complications being diarrhoea and inappetance. Intra-abdominal adhesions were identified in 2/8 horses requiring a second celiotomy. Long-term follow-up was available for 45 horses and 87% (39/45) were alive at least 12 months after surgery. CONCLUSIONS: As previously reported, faecalith obstruction is a frequent surgical lesion in the miniature horse and is most common in miniature horses age <6 months. The incidence of adhesion formation may be lower than previously reported.     

A review of research into second intention equine wound healing using manuka honey: Current recommendations and future applications

In addition to the generic properties of honey, manuka honey has a nonperoxide antimicrobial activity largely attributed to methylglyoxal. Commercially, manuka honey is graded against a standard antiseptic, phenol, to provide a measure of antimicrobial activity referred to as the unique manuka factor (UMF). The higher the UMF, the greater the antimicrobial activity. However, more recently, there is evidence that manuka honey can also modulate the initial inflammatory response through activation of toll‐like receptor 4 on monocytes to enhance production of cytokines important in tissue repair and regeneration. Recent studies investigating the effects of manuka honey on second intention healing of lower limb wounds in horses have shown that wounds treated with UMF 20 manuka honey retracted less and healed faster than untreated wounds. Using this wound healing model, the primary effects of manuka honey appeared to be associated with the modulation of the initial inflammatory reaction rather than its antimicrobial effects. Based on the current knowledge, treatment with manuka honey should be instituted as soon as possible after injury. Where bacterial contamination is substantial, manuka honey with a UMF ≥15 should be used. While bandages will improve the contact between the honey and the wound and may be indicated in the early stages of wound healing, prolonged bandaging may lead to the production of excessive granulation tissue. If topical treatment without a bandage is to be used, more honey is not necessarily better. Using a thin film combined with regular application, contact times may be optimised. Application 2–3 times daily to open wounds may improve efficacy. Manuka honey should be applied for at least 21 days after wounding but there may be beneficial effects if it is applied until wound healing is almost complete.     

Detection of clade 2 equine influenza virus in an adult horse recently imported to the USA

A 4‐year‐old Warmblood mare presented to the William R. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California at Davis with bilateral mucoid nasal discharge and pyrexia. The mare had recently been imported from Germany, arriving at a quarantine holding facility 72 h prior to presentation. Based on clinical presentation and culture results of tracheal fluid, the mare was diagnosed with bacterial bronchopneumonia secondary to equine influenza. The equine influenza virus (EIV) identified in the imported mare displayed 99.1% nucleotide homology of the HA1 gene to the prototype Florida sublineage clade 2 isolate A/equine/Richmond/1/2007 (H3N8). This case illustrates the risk of introducing a clade 2 EIV in North America.     

Epidemiology of Mycobacterium bovis infection in feral ferrets (Mustela furo) in New Zealand: I. Pathology and diagnosis

Necropsies of 228 ferrets captured from eight areas in the North and South Islands provided material for an investigation into the epidemiology of tuberculosis in feral ferrets. Mycobacterial culture of pooled lymph nodes (retropharyngeal, respiratory and jejunal) identified the prevalence of infection to be much higher than that estimated from gross lesions only. Seventy-three of the 228 animals examined (32%) were diagnosed as tuberculous. Fifty-three culture-positive ferrets and 18 seemingly uninfected animals were subjected to detailed histopathological examination. The outcomes of these investigations, including the characteristics of the disease, distribution of lesions and aids to diagnosis, are presented.

Of the feral carnivores found in New Zealand, the disease persists at high prevalence only in ferrets, and is probably maintained principally by ingestion of tuberculous carrion. The course of the disease may be prolonged in some ferrets, but tuberculosis eventually causes the death of many infected animals. Microscopic hepatic granulomas may be considered pathognomonic of the disease, and have potential to be used as a rapid diagnostic tool in ferrets with no gross lesions.     

Thoracotomy for repair of a large dorsal diaphragmatic hernia in an 18‐year‐old mare

An 18‐year‐old Arabian‐mix mare was presented with a history of severe colic. Emergency exploratory celiotomy revealed diaphragmatic hernia, with a large rent in the left dorsal aspect of the diaphragm and large colon volvulus. Attempts to close the defect in the diaphragm in dorsal recumbency were unsuccessful. Therefore, a thoracic approach through lateral thoracotomy was elected, and a mesh was attached to the diaphragm using skin staples. While in dorsal recumbency, the mare suffered from significant respiratory acidosis. Thus, the mare was tilted into reverse Trendelenburg (30° head upward) and ventilation improved markedly. The mare recovered uneventfully, and was doing well 5 years after surgery.     

Risk of anesthesia-related complications in draft horses: a retrospective,single-center analysis

ObjectiveTo report anesthetic-related complications and determine risks associated with anesthesia in draft horses.Study designRetrospective study.AnimalsA total of 401 anesthetic records for draft horse breeds that underwent general anesthesia from January 2010 through December 2020 were reviewed; horses euthanized during general anesthesia were excluded.MethodsDemographics, perioperative drugs used, procedure type and duration, time to extubation, number of attempts to stand, use of sling in recovery and perioperative morbidity and mortality were investigated. Morbidity and mortality statistical evaluation included univariable logistic regression analysis and ordinal regression analysis.ResultsAmerican Society of Anesthesiologists (ASA) status I–II, ASA III–V and total mortality rate for all cases was 0.69% (2/288), 6.19% (7/113) and 2.24% (9/401), respectively, with Belgian horses being overrepresented (6/9). Cardiac arrest occurred in six out of nine horses that died without euthanasia, and five out of six of these horses underwent colic surgery. Factors associated with increased mortality risk included ASA status of III–V, increased body weight, emergency status and horses presenting for colic. Hypotension, hypercarbia and hypoxemia occurred in 56% (224/401), 46% (186/401) and 14% (58/401) of horses, respectively. During recovery from anesthesia, lighter horses and horses undergoing shorter anesthetic procedures were more likely to be successful on the first or second attempt to stand and were less likely to require a sling in recovery.Conclusions and clinical relevanceDraft horses undergoing general anesthesia had a higher mortality rate than previously reported for all types and breeds of horses.     

Atypical thymoma in a horse: Diagnostic approach and application of an alternative histological classification system

Thymoma is a rare condition in horses. This case of a 24-year-old Warmblood gelding that was presented with oedema and signs of vascular congestion of the left forelimb caused by a thoracic mass is described. The diagnostic work-up included blood chemistry, cytology of pleural effusion, ultrasonography, radiography and the visualisation and collection of a tissue sample by thoracoscopy. Finally, post-mortem findings and histopathology revealed thymic epithelial neoplasia with histomorphologic features previously unreported in horses. The unique mixture of spindle-shaped and epithelioid tumour cells in combination with clear features of malignancy suggested the application of the Moran and Suster histological classification system for thymomas in humans (Moran and Suster, 2008, Curr. Treat. Options Oncol., 9, 288), which has not been reported in an equine case before and fits well to the present case.     

Pathology of gastritis and gastric ulceration in the horse. Part 1: Range of lesions present in 21 mature individuals

Reasons for performing study: Gastric ulceration is now widely recognised as an important disease in high performance horses. Little is known about gastric histopathology in healthy or diseased animals; a comprehensive assessment would enhance interpretation of gross findings through assessment of their accuracy and allow for identification of lesion variety and pathogenesis in different anatomical regions of the stomach. Objectives: To investigate the true extent and variety of gastric lesions in a mixed population of mature horses at post mortem. Methods: Stomachs were removed from a mixed population of 21 horses at post mortem. Mucosal abnormalities were recorded in photographic and written form. Representative samples from all gross lesions were taken for histopathology and processed routinely. Special stains including Gram, PAS and Warthin Starry, were used when appropriate. Pathological classification of lesion type using both gross and histological appearances was performed. Results: Classification of lesions within the squamous region included hyperkeratosis, punctate scars, diffuse erosions/ulcerations and margo injuria; and within the glandular region, hyperaemia, focal erosions and ulcerations. Glandular metaplasia was recognised for the first time in the equine stomach. No Helicobacter‐like organisms were detected in association with lesion development. Conclusions and potential relevance: This study used gross and histological examination to highlight the large variety of naturally occurring gastric lesions in a mixed population of horses. Analysis of the pathogenesis of lesion development is now possible. Further research regarding the range of pathology in larger, more diverse groups of horses is required.     

Autoserum preparation in the treatment of equine summer eczema: Findings over 12 years

Equine summer eczema, the most common allergic skin disease of the horse, is notoriously difficult to treat with available methods. In the present study, 343 horses were treated with an autogenous serum preparation made from their highly diluted sera. This work was a continuation of the earlier, randomised and placebo controlled study on the autoserum therapy that showed a significant, positive clinical effect and was carried out on a series of horses in 1997–98. The main aim of the present study was to collect long‐term information from the owners on this therapy. In the period from 1997–2008, 70% of the horses benefited from the treatment and 16% did not, while 14% of owners could give no clear opinion. After a 5 year follow‐up, horses treated with autoserum had significantly milder clinical signs of summer eczema than before this treatment. No harmful side effects were found. An autoserum preparation was shown to be a feasible alternative in the treatment of equine summer eczema.