Hagyard Equine Medical Institute

Large colon volvulus is a common, life-threatening cause of colic in horses. Gastrointestinal neoplasia is rare, especially in young horses, but it may contribute to acute abdominal pain. A 1-year-old Standardbred colt presented with acute colic unres

SummaryThe aim of this observational retrospective case series was to document and describe the use of an overlapping suture technique used to close ventral midline incisional hernias, known as the ‘vest‐over‐pants’ method. The records of fourteen horses at a single institution from March 2004 to October 2024 were reviewed. Cases underwent ventral midline incisional hernia repair using an interrupted overlapping technique (‘vest‐over‐pants’ pattern). A total of 14 repairs were performed with a total of 14 cases where the hernia was surgically corrected and did not reoccur within the study period (100%). On average, the incisional hernia repair occurred 208 days after the last celiotomy (± 11 days), with the mean patient age being 3.4 years (5 months to 9 years). The average post‐operative hospitalisation period was 3 days (2–7 days). The duration of stall confinement varied, with three horses being confined to a stall for 30–45 days, nine horses for 21 days and two for 14 days. Post‐operative pain was observed in one of the 14 cases (7%). In all cases, incisional seroma formation was noted in the first week after surgery. Mild focal incisional drainage was noted in 4 of the 14 cases (29%). The results of this case series display support for the clinical use of a ‘vest‐over‐pants’ pattern to repair ventral midline incisional hernias.

The lateral trochlear ridge (LTR) of the femur is the most common predilection site for osteochondritis dissecans (OCD) in the equine stifle. The objective was to investigate the relationship between lesion size, racing performance, and sale result of Thoroughbreds with LTR OCD following arthroscopic removal as a yearling. In this retrospective study, medical records of 145 Thoroughbreds from one equine hospital that underwent surgery for LTR OCD were reviewed; the length and depth of the lesions were measured on preoperative radiographs. Horses were allocated to group S if they were presented to a public yearling sale post-surgery, and horses in group NS were not. Each horse from group S was matched with two control horses from the same sale (group C). Influence of lesion size on racing performance and sale result was analyzed. Racing performance and sale results were compared between different categories of OCD lesion sizes and between the groups. Lesion length and depth did not affect racing performance and did not differ between group S and group NS. However, group S did perform significantly better than group NS. When comparing groups S and C, there were no significant differences in racing performance and sale result. Thoroughbreds that had arthroscopic surgery for LTR OCD as a yearling and were presented on a public yearling sale performed comparable to Thoroughbreds that showed similar potential as a yearling. Sale result is not significantly affected in our study.

SummaryThis case report describes the treatment and outcome of a 3.5‐month‐old lame foal, with a history of pneumonia associated withRhodococcus equi. Clinical examination identified osteomyelitis of the scapulohumeral joint. The unusual location of theRhodococcus equiosteomyelitis unresponsive to prevention and adequate treatment led to euthanasia of the patient. Post‐mortem findings confirmed bronchopneumonia due toRhodococcus equias well as the osteomyelitis of the scapulohumeral joint. This case highlights thatRhodococcus equishould 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.

Ultrasonic determination of fetal sex is a useful management tool for the horse owner. The potential value of the offspring varies depending on the sex, the sire, and the dam. Equine fetal sex determination may be performed at three different periods of gestation. The earliest stage is the transrectal ultrasonographic evaluation of the fetal genital tubercle performed between 55 and 90 days of gestation. The second stage at which fetal sex can be determined is at 90–150 days of gestation. The third stage for sex determination is at 150 days and beyond and is performed using a transabdominal ultrasound approach. This chapter discusses the processes involved in these periods of gestation. The most accurate and efficient time period in which to determine fetal sex is between days 60 and 70 of gestation.

The rectum is the terminal part of the large intestine: it extends from the pelvic inlet to the anus with an approximate length of 30 cm. The anus is the terminal part of the alimentary canal. The muscular arrangement of the anus contains the sphincter ani internus and the sphincter ani externus. The most common surgery that is performed in the rectal region is for perineal lacerations. These injuries are most often sustained in foaling. This chapter presents the definition, risk factors, pathogenesis, prevention, diagnosis, treatment, and expected outcome for the technical complications, early postoperative complications, and intraoperative complications associated with surgery of the rectum and anus.

Osteochondritis dissecans (OCD) of the distal intermediate ridge of the tibia (DIRT) is commonly identified on either the lateral to medial (LM) or dorso45°medial-plantarolateral oblique (D45M-PLO) projection of the tarsus. This manuscript describes a retrospective case series out of Hagyard Equine Medical Institute, for which medical records and radiographic projections of the tarsus were reviewed, consistent with Keeneland's repository requirements. This original investigation identified seven yearling Thoroughbred horses between 2008 and 2018 with radiographic signs of atypical osteochondrosis lesions within the tarsus. The atypical lesions, originating along the medial margin of the distal intermediate ridge of the tibia, were initially only diagnosed on the dorso10°lateral-plantaromedial (D10L-PMO) projection and were overlooked on the LM and D45M-PLO views. Following the diagnosis of osteochondrosis in these seven cases, the radiographs were reviewed and re-evaluated, but osteochondrosis and/or fragmentation could not be definitively diagnosed on the LM and/or D45M-PLO projections alone. Our findings highlight the importance of a complete radiographic study of the equine tarsus when screening horses for OCD lesions of the distal intermediate ridge of the tibia and that atypical DIRT lesions may go undetected if the D10L-PMO projection is not performed.