Summary A 16‐year‐old Thoroughbred mare presented with a 1‐year history of a growing mass on the rostral mandible. Biopsy performed by the referring veterinarian revealed chronic granulating fibrosis and stomatitis. Due to progressive loss of body condition and increasing size, the mare presented to the clinic. Radiographic examination of the mandible revealed osteolytic lesions. Mandibulectomy was performed under general anaesthesia. The horse's demeanour and feed intake improved significantly and the cosmetic outcome was acceptable. Histopathological examination confirmed a sarcoma, most likely a fibrosarcoma.

The month-specific ACTH RIs generated in this study will improve the accuracy of diagnosis and monitoring of PPID in the local equine population. These results highlighted the previously recommended need for seasonal and location-specific RIs.

Zusammenfassung: Diese Studie gibt einen Überblick über 25 intra operationem entnommene und histologisch, sowie immunhistologisch aufgearbeitete Umfangsvermehrungen des Pferdedarms. Es wurden Proben von 25 Pferden mit einem Alter von 2 -25 Jahren mit anatomischer Assoziation zum Dünn-oder Dickdarm in die Studie einbezogen. Knapp die Hälfte der Tiere waren weiblich. Der Großteil der Patienten waren Warmblüter, weiterhin zwei Ponys, Andalusier, zwei Kaltblüter sowie ein Quarter Horse und ein Gangpferd. Die Proben wurden in Formalin fixiert und gemäß den Standardanweisungen aufgearbeitet. Die histologische Diagnose und immunhistologischen Befunde wurden im klinischen Kontext bewertet. Klinisch und makroskopisch konnte keine Vorhersage hinsichtlich der Art und Dignität der Umfangsvermehrungen getroffen werden. Die klinischen Symptome in Form von Kolik, Anorexie, Durchfall oder Fieber waren unspezifisch. In zwei Fällen handelte es sich um nicht neoplastische Veränderungen (Hämatom und chronisches Granulationsgewebe). Bei den Tumoren machten die Spindelzelltumoren den größten Anteil aus (vier Leiomyome, drei Leiomyosarkome, ein GIST). Die zweitgrößte Gruppe stellten die Lymphome (7/25) dar. Fünf Umfangsvermehrungen wurden als Adenokarzinome klassifiziert, wovon drei eine knöchernde Metaplasie aufwiesen. Weiterhin fanden sich drei noduläre Gefäßproliferate. Eine Rassen-oder Geschlechtsdisposition konnte nicht festgestellt werden. Alle Pferde, zu denen Angaben vorlagen, wurden bereits intra operationem euthanasiert. Da die klinischen Symptome sehr variabel sind, sich aber je nach Zellursprung bzw. Dignität bedeutende Unterschiede hinsichtlich der Prognose ergeben können, ist eine chirurgische Exstirpation und anschließende histopathologische Untersuchung anzuraten. Weiterhin sollte insbesondere bei Abmagerung und rezidivierende Koliken an eine Umfangsvermehrung des Darms als Ursache gedacht werden, die aber nicht immer maligne ist. Schlüsselwörter: GIST, intestinales Lymphom, Adenokarzinom, Sarkom, knöchernde Metaplasie Intestinal tumors and tumor-like lesions in horsesIntestinal neoplasia is rare in horses. Lymphoma is the most common form, other intestinal neoplasms include adenocarcinoma, leiomyoma, leiomyosarcoma or gastrointestinal stromal tumors (GIST). Clinical signs are non-specific and include weight loss, colic or diarrhea. The aim of this study was to evaluate tissue samples from 25 horses with intestinal masses. We collected tissue material from 25 horses with masses in the small or large intestine between 2011 and 2017. Included were only samples directly connected to the intestine which were submitted for routine diagnostics. Clinical history was included. Tissue samples were formalin-fixed and embedded using standard methods. Histology and immunohistology (Vimentin, SMA, Desmin, S100, c-Kit, CD20, CD3, FVIII, CD31, cytokeratin) were performed. In 20 cases the clinical history was known. The horses' age ranged from 2-22 years (median 13 years). Patients showed poor body condition, weight loss or cachexia (2...

A four-months-old equine Holstein colt was presented with acute signs of respiratory disease. Following diagnostic evaluation, an initial diagnosis of pneumonia was made and treatment with broad-spectrum antimicrobials, intravenous fluid therapy, polymyxin B, clenbuterol, and dembrexine was initiated. The colt's condition deteriorated under therapy and repeat ultrasonographic evaluation revealed an accumulation of free fluid in the abdomen. On abdominoscentesis urine was obtained. Urethral endoscopy revealed hyperemic urethral mucosa and a hard, irregular, greyish structure 35 cm into the urethra. Surgery under general anesthesia was attempted and an area of necrotic tissue was found on the ventral aspect of the bladder. A spiculated oval stone was exteriorized but the defect could not be repaired as it was not accessible. The colt was euthanized. Urolith analysis revealed a composition of 90 % tripelphosphate (struvite) and 8.2 % apatite (rich in calcium). This case emphasizes the potential of obstructing urinary disease in very young animals. Knowledge of the potential presence of significant uroliths in suckling foals may help guide diagnostic evaluation and treatment and potentially allow for early intervention to prevent a fatal outcome. Case historyA four-months-old equine Holstein colt was presented for further investigation of pyrexia. The barn manager reported that the foal was found to be more quiet than usual with a rectal temperature of 40.2 °C. The attending veterinarian recommended referral. The foal was born and housed in a breeding facility with a total of 35 mares and their foals. The horses were housed in group-stalls with daily turnout on pasture. The mares were fed a commercial concentrate and grass hay ad libitum as well as a mineral supplement. Reportedly, no other horses on the premises were affected.

The acute phase protein serum amyloid A (SAA) has become widely used as a diagnostic aid for the early detection of inflammation. SAA increases by more than 25 % in 24 to 38 hours after tissue damage caused by trauma or infection. To determine the increase in serum amyloid A (SAA) following colic surgery and to compare it to changes in leukocyte count, client owned horses > 2 years of age, presented for colic with emergency laparotomy were used. Whole blood SAA concentration and leukocyte count were determined before surgery and at 48, 72, and 96 hours post-surgery. Lesions were classified as non-inflammatory or inflammatory during surgery. 61 horses underwent emergency laparotomy; 44 horses were excluded. Of the remaining 17 horses, 12 had non-inflammatory, 5 inflammatory lesions. Before surgery SAA concentrations in horses classified as non-inflammatory ranged from 0 to 217 μg/mL (median 14 μg/mL, range 10-18) and from 0 to 987 μg/mL (median 162 μg/mL, range 162) in inflammatory cases. In all horses SAA concentrations increased significantly 48 hours post-surgery (p = 0.002), horses with inflammatory lesions had significantly higher SAA concentrations (median 2750 μg/mL, range 1916-2835) compared to non-inflammatory lesions (median 624 μg/mL, range 471-740) at 48 (p = 0.0004), 72 (p = 0.0009), and 96 (p = 0.0007) hours post-surgery. Maximum SAA concentration was observed 48-72 hours post-surgery in all cases. White blood cell count (WBC) revealed a mild decrease post-surgically in some cases. At discharge all horses had SAA concentrations < 200 μg/mL. Differences in SAA concentrations between inflammatory and non-inflammatory cases can be expected. The knowledge of normal postoperative SAA concentrations is essential if SAA is used for monitoring occurrence of postoperative infections.