Computed tomographic diagnosis: Traumatic lingual process fracture and surgical resection

A 9‐year‐old mare was presented with abnormal behaviour and head‐shaking when ridden. Pathology of the hyoid apparatus was suspected and computed tomographic (CT) examination of the head was suggested. Computed tomographic images revealed a fractured lingual process (LP) of the basihyoid bone. Surgical resection of the fractured LP was performed. The mare recovered uneventfully and symptoms improved 10 weeks post‐operatively.     

Noncitrated blood transfusions used as adjunctive treatment in a 7‐year‐old Shetland Pony with haemoperitoneum due to a ruptured corpus haemorrhagicum

Chronic bleeding due to extensive haemorrhage from a ruptured corpus haemorrhagicum developed 2–4 weeks after parturition and was identified as the cause for a haemoperitoneum in a 7‐year‐old Shetland Pony mare, leading to anaemia. Diagnosis was made upon exploratory coeliotomy and a unilateral ovariectomy was performed. Intra‐ and post operatively, the mare received autologous blood transfusions of noncitrated blood. To our knowledge, this is the first report of an autologous blood transfusion accomplished using noncitrated blood collected from the abdominal cavity.     

Direct approach to the nasal cavity through a bone flap for the treatment of a large nasal cyst

A 21‐year‐old Warmblood mare was referred to the Equine Department, Vetsuisse Faculty, University of Zurich, because of recurrent unilateral nasal discharge 3 months after partial removal of a large cyst from the left maxillary and frontal sinuses. Endoscopic, radiographic and computed tomographic examinations showed that the remnant of the cyst, which originally had extended from the left maxillary and frontal sinuses into the left nasal cavity, had expanded and was obliterating the left middle nasal meatus. A direct surgical approach to the cyst through the left nasal and maxillary bones rostral to the facial crest was chosen, which allowed evaluation and removal of the entire cyst. Endoscopic examination 3 days post operatively showed no remnants of the cyst, and the mare was discharged in good health. Re‐examination one year later showed no recurrence of the cyst.     

Granulosa cell tumour: An interesting case in a pregnant mare

This report describes the successful management of a pregnant 14‐year‐old seven‐eighths Thoroughbred mare with an ovarian granulosa cell tumour. The mare initially presented with unilateral ovarian enlargement whilst being managed for artificial insemination, demonstrating normal ovarian function with ovulation from the contralateral ovary leading to conception. The mare subsequently re‐presented with stallion‐like behaviour at 3.5 months gestation and ovarian suppression was evident. The mare maintained her pregnancy and delivered a live colt foal at term. Ovariectomy was performed 3 months post foaling and the mare regained cyclic activity 9 months post surgery. The mare then conceived and became pregnant once more. The diagnostic and therapeutic challenges during pregnancy are discussed.     

Facial varicosity affecting the lower eyelid of a horse

A 12‐year‐old Clydesdale cross mare was referred for investigation of right periocular vascular distension. Physical examination and ultrasonography confirmed the presence of a varicosity of the veins of the lower eyelid and transverse facial vein. The size of the varicose vein led to concerns about the potential progression in size of the lower eyelid to obstruct vision. Percutaneous encircling sutures were ineffective at occluding the vessel and surgical excision of the abnormal vein was performed. This treatment approach proved effective and 7 months post operatively the swelling has not recurred. This case demonstrates that varicosities can be successfully surgically resected in horses if there is a clinical indication.     

Single‐port laparoscopic incisional hernia repair in a horse

A 16‐year‐old Italian Saddle Horse gelding was referred for treatment of an incisional hernia that developed 7 months after a ventral midline laparotomy for treatment of acute abdominal pain. Physical examination revealed a hernia approximately 20 cm long and 15 cm wide on the ventral aspect of the abdomen. Ultrasonography revealed the dimensions of the hernia ring to be approximately 15 cm in length and 10 cm in width. A single‐port laparoscopic incisional hernia repair using an operating 0° laparoscope was performed with an appropriately sized (24 × 18 cm) piece of mesh fixed in place with simple interrupted transabdominal sutures. At 4 weeks post operatively, follow‐up physical examination and ultrasonography confirmed healing of the surgical site with no evidence of hernia recurrence. The same evaluation was done 6 months post operatively, and the horse returned to its previous level of activity 8 months post operatively. In horses, laparoscopic application of mesh should be considered among the treatment options for incisional hernia. In the present case, this technique was performed with a single port using an operative laparoscope, in contrast to the multiportal techniques reported previously. The case presented here demonstrates that single‐port laparoscopic herniorrhaphy is feasible, and allows proper placement of an expanded polytetrafluoroethylene intraperitoneal mesh in horses     

Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm

To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting.     

Prolonged anesthesia using sevoflurane,remifentanil and dexmedetomidine in a horse

HistoryA 10–year old Arabian mare had a slow–growing mass on the lower right mandible and required a large partial mandibulectomy.Physical examinationNo abnormalities were detected apart from the mass.ManagementA temporary tracheostomy was performed pre–operatively. Anesthesia was induced with xylazine followed by ketamine and diazepam. For 13 hours, anesthesia was maintained using sevoflurane, dexmedetomidine and remifentanil infusions, with the exception of surgical preparation time. Intra–operatively, ventilation was delivered through the cuffed tracheotomy tube. Heart and respiratory rates, ECG, arterial pressures, inspired and expired gases, pulse oximetry values and body temperature were monitored. Dobutamine and whole blood were necessary, and romifidine was used to control recovery. Post–operatively, phenylbutazone and buprenorphine given systemically and bupivacaine administered through a wound soaker catheter were used to provide analgesia. Head–shaking from buprenorphine was controlled with acepromazine and detomidine once standing after 87 minutes in recovery. For 3 days after surgery, analgesia was provided with butorphanol, phenylbutazone and bupivacaine. The mare recovered well, appeared comfortable and started eating the following day with no signs of ileus.Follow–upSeven months later, the mare was doing well.ConclusionsSevoflurane, dexmedetomidine and remifentanil infusions were suitable for a long and invasive procedure.     

Treatment of sustained monomorphic narrow‐complex ventricular tachycardia in a 16‐year‐old Arab mare with a constant rate of infusion of lidocaine and oral propranolol

A 16‐year‐old Arab mare was referred for treatment of a tachydysrhythmia detected on electrocardiogram by the referring veterinarian. Monomorphic, narrow‐complex ventricular tachycardia (VT) was confirmed by electro‐cardiogram in a normal base‐apex configuration. Subsequent diagnostic testing, including echocardiography and measurement of plasma cardiac troponin concentration, did not reveal a definitive cause for the dysrhythmia. Conversion of VT to ventricular bigeminy occurred following treatment with magnesium sulfate and lidocaine hydrochloride, administered intravenously. Treatment with orally administered propranolol subsequently led to conversion to sinus rhythm with intermittent ventricular premature complexes (VPCs). Oral prednisolone treatment was also initiated to address the possibility that VT resulted from underlying myocarditis. The mare was discharged with oral propranolol, a tapering course of prednisolone, and exercise restriction. Follow‐up cardiac examination 6 weeks later revealed persistent, intermittent VPCs and reversion to VT occurred during exercise. Sinus rhythm with intermittent VPCs was re‐established following the administration of lidocaine. The mare was again discharged with oral propranolol therapy, which was subsequently replaced with oral sotalol. Sudden death occurred 4 weeks later but a post mortem examination was not performed.     

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.     

The effects of endometrial damage on placental and fetal development in a mare

A 13-year-old ex-polo pony maiden mare with an extensively damaged endometrium was initially used as an embryo donor in a research herd. Embryos recovered from the mare were of normal morphology and size. Subsequently, the mare was inseminated and left pregnant. Early conceptus development was normal and she foaled a small (22 kg) but healthy filly after a gestation of 360 days. Examination of the placenta showed that development of the microcotyledons accurately reflected the damage to the uterus. Plasma progestagen profiles throughout gestation also provided evidence for placental pathology and fetal stress.     

Pancreatic mixed acinar-endocrine carcinoma in a dog

A 10.5‐year‐old crossbreed dog was presented with a history of hypoglycaemic episodes and elevated serum insulin concentration. A pancreatic mass was removed at surgery along with an enlarged draining lymph node. An unresectable hepatic nodule was also present. Immunohistochemistry confirmed the pancreatic and lymph node masses as functional mixed acinar‐endocrine carcinoma, previously unreported in domestic species. Persistent hypoglycaemia and hyperinsulinaemia post‐operatively was highly suggestive of the hepatic mass being a functional metastasis. The dog was managed on prednisolone and remained asymptomatic 9 months post‐operatively. This tumour type has only been rarely reported in human patients and may highlight the need for more rigorous immunohistochemical staining of pancreatic masses in veterinary species to identify the prevalence of this tumour type.     

Adverse effects of intrapleural instillation of tissue plasminogen activator in a horse: Suspected re‐expansion pulmonary oedema

This case report describes a 5‐year‐old pregnant Warmblood mare that was being treated for fibrinous bacterial pleuropneumonia. Since initial attempts to drain and lavage both pleural cavities were ineffective due to the presence of extensive intrapleural fibrin loculations, recombinant human tissue plasminogen activator (tPA) was instilled into both pleural cavities, to promote fibrinolysis and improve drainage. Within 1–2 h of instilling tPA, the horse became distressed, with increasing dyspnoea, tachycardia, pleurodynia and hypoxaemia. At 4 h post tPA instillation, diffuse bilateral pulmonary oedema was evidenced by the onset of widespread audible inspiratory crackles and ultrasonographic ring‐down artefacts. Ultrasonography demonstrated that tPA had induced pleural fibrinolysis, thereby removing the restrictive effects of pleural adhesions on lung motion and facilitating lung re‐expansion. Re‐expansion pulmonary oedema was suspected, although an adverse drug reaction could not be excluded. The complication resolved with nasal oxygen supplementation, and administration of frusemide, meloxicam, morphine and hydroxyethyl starch. Subsequent repetition of intrapleural tPA instillation and thoracic drainage had no apparent adverse effect. The mare was discharged from the hospital and subsequently foaled successfully. The pathogenesis, diagnosis and management of re‐expansion pulmonary oedema are reviewed.     

Comparative histomorphological study of endometrium in mares

Uterine acute post‐breeding inflammation is a physiological tissue response to the entry of exogenous elements, with persistent endometritis being the main pathology responsible for subfertility in the mare (Equus ferus caballus; Linnaeus, 1758). Mares can be classified as susceptible or resistant to endometritis according to their ability to remove intrauterine fluid within 48 hr after experimental inoculation. Endometrial biopsy is a technique that is commonly used to establish the degree of lesions that can affect the fertility of the mare. Endometrial histomorphometry is an objective and highly precise diagnostic method. The aim of this study was to compare, during oestrus, the endometrial histomorphometry of mares previously classified as susceptible (SM) or resistant (RM) to endometritis. Endometrial biopsies from 24 mares at the oestrus phase of the cycle were obtained. For the histomorphometric analysis, samples were histologically processed and subjected to routine Haematoxylin–Eosin staining. For the evaluation, the variables were considered as follows: 1‐Height of the lining and glandular epithelia (Lining SM = 15.9 μm vs. RM = 13.3 μm; Glandular SM = 15.0 μm vs. RM = 13.0 μm); 2‐Perpendicular diameters of endometrial glands (SM = 51.3 μm vs. RM = 44.8 μm); 3‐Number of endometrial glands per field (SM = 24.8 glands/field vs. RM = 20.5 glands/field). The results from this study suggest the existence of a relationship between the studied characteristics and the susceptibility/resistance to post‐breeding endometritis in mares. Thus, increased epithelial height, greater glandular density and greater development of the glands during oestrus would be related to a higher susceptibility to endometritis.     

Partial gastrectomy and total splenectomy for the treatment of a gastric mass in a horse

A 9-year-old cob mare with a history of recurrent colic presented during an acute colic episode. Ultrasonography revealed a mass emanating from the greater curvature of the stomach and was tightly adhered to the cranial edge of the spleen. Partial gastrectomy and total splenectomy were performed via a midline celiotomy incision. The mass was subsequently confirmed to be granulomatous inflammation, postulated to be secondary to a penetrating injury to the stomach. Post-operatively, the mare had episodes of recurrent colic that were successfully managed with optimisation of the horse's diet and feeding regime. At 10 months’ post-operatively the mare was managed on full turn out, with no evidence of colic and had returned to the previous level of ridden work. The horse then presented 14 months post-operatively with severe colic due to a large colon impaction and displacement and was euthanased. This is the first report to describe successful partial gastrectomy as a treatment option for a gastric mass in the horse.     

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.     

Chronic intermittent colic in a mare attributed to uterine marbles

A 13‐year‐old Quarter Horse mare presented for evaluation of chronic intermittent colic. Following extensive diagnostics, abdominal radiographs revealed two round, radiopaque objects in the caudal abdomen. Palpation per rectum and transrectal ultrasonography of the reproductive tract confirmed that the round objects were uterine marbles. Dinoprost tromethamine (Lutalyse, 5 mg i.m. q. 24 h for 2 days) was administered to bring the mare into oestrus, and both uterine marbles were manually removed from the uterus following digital dilation of the relaxed cervix. Follow‐up with the owner 12 months after discharge revealed that the mare had shown no further signs of abdominal discomfort since having the uterine marbles removed. To the authors' knowledge, this is the first published report of chronic intermittent colic attributed to uterine marbles in a mare.     

Acupuncture and traditional Chinese veterinary medicine for treatment of a mare with rectal paralysis

An 8‐year‐old Appaloosa mare with rectal paralysis due to a cosmetic ethanol ‘tail block’ was treated with traditional Chinese veterinary medicine treatments including acupuncture and herbal medicine. Her rectal and tail tone gradually improved after the treatment. At 4 months after initial presentation, the mare was able to produce faecal piles on a regular basis, and manual evacuations were no longer needed. Significant improvement was within 30 days of beginning treatment. At 8 months, the owner indicated that the mare had normal defaecation, was able to swish the tail from side to side and lift the tail to urinate, and had no evidence of straining to defaecate or colic.     

Effects of Supplementing Holstein Heifers with Dietary Melatonin during Late Gestation on Growth and Cardiovascular Measurements of their Offspring

The objective was to examine the effects of supplementing dams with dietary melatonin during late gestation on offspring growth and cardiovascular measurements. On day 190 of gestation, heifers (n = 20) were blocked by body weight and randomly assigned to one of two dietary treatments consisting of 20 mg of dietary melatonin per day [melatonin (MEL)] or no melatonin supplementation [control (CON)]. Dietary treatments were terminated on day 262 of gestation. At birth, calves were separated from their dams with no further treatments. Calf (n = 18) blood pressure, cortisol, nitrites and total antioxidant capacity were collected on weeks 0, 1, 2, 3 and 4 of age. Calf hepatic portal blood flow and concentrations of insulin‐like growth factor 1 were determined on weeks 0 and 4 of age. Calf body weight, abdominal girth, hip height and wither height increased (p < 0.05) with age. An age by treatment interaction (p < 0.01) was observed for calf body weight, which was increased at weeks 8 and 9 of age in calves born to MEL heifers compared to calves born to CON heifers. Pulse pressure, mean arterial pressure, absolute hepatic portal blood flow and blood flow relative to calf body weight were not different (p > 0.05) between treatments. A main effect of calf age (p < 0.05) was observed for concentrations of insulin‐like growth factor 1, which was decreased at week 4 compared to week 0. An age by treatment interaction (p < 0.05) was observed for cortisol, which was decreased at week 2 in calves from MEL‐treated dams compared to calves from CON‐treated dams. Early post‐natal growth was altered in offspring born to dams supplemented with dietary melatonin. This could lead to further foetal programming implications in conjunction with post‐natal development.