Standing thyroidectomy in 10 horses.

OBJECTIVE: To describe a surgical technique for thyroidectomy in horses with thyroid neoplasia under standing sedation and local anesthesia. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned horses (n = 10). METHODS: Medical records of horses with a history of thyroid enlargement were included in the study if thyroid gland enlargement was treated surgically via hemi- or bilateral thyroidectomy, with the horse standing and sedated. Data derived from follow-up clinical examination, performance level, recurrence, and cosmetic outcome were evaluated. RESULTS: Thyroid enlargement was unilateral in 8 and bilateral in 2 horses. Histopathological findings included adenomas (5/10), adenocarcinomas (2/10), cystic hyperplasia (2/10), and C-cell adenoma (1/10). No major complications were encountered during or after surgery. All horses resumed their previous level of exercise within 6 weeks. Recurrence was diagnosed in 1 horse, 7 months after excision, and a second surgery was required. Recurrent laryngeal nerve neuropathy and seroma formation subsequent to surgery were not recorded in any of the cases. CONCLUSION: Thyroidectomy can safely be performed with the horse standing and sedated with local anesthesia. CLINICAL RELEVANCE: Performing standing thyroidectomy does not increase intraoperative or postoperative complications and could be considered for horses with thyroid enlargement amenable to surgery.

A study comparing the healthy and diseased equine glandular gastric microbiota sampled with sheathed transendoscopic cytology brushes.

The role of the equine gastrointestinal microbiota in the pathogenesis of equine glandular gastric disease (EGGD) is poorly understood. To investigate whether the glandular gastric microbiota is altered in horses with EGGD. Prospective longitudinal study. Five Thoroughbred racehorses from one training center underwent gastroscopy as part of poor performance investigation. Samples were taken from EGGD lesions and adjacent normal mucosa using sheathed transendoscopic cytology brushes and frozen at -80°C. DNA was extracted for 16S rRNA sequencing, and sequences compared against a database to generate taxonomic classification of the microbiota. The same horses were sampled 6 months later. Normal glandular mucosal samples were characterized by a higher proportion of Proteobacteria (46.3%) than EGGD lesions (18.9%). Relative abundance of Firmicutes was lower in samples from normal mucosa (20.0%) than EGGD lesions (41.2%). Linear discriminant analysis effect size (LEfSe) confirmed a greater proportion of Firmicutes species was characteristic of samples collected from EGGD lesions due to a very high relative abundance of Sarcina (up to 92.4%) in two horses with EGGD. We were unable to comment on the stability of the glandular gastric microbiota over time. Small sample population. None of the horses examined had grossly normal gastric mucosa. The gastric microbiota appears altered in EGGD, although we are unable to demonstrate a causative effect. Sarcina was particularly increased in abundance in EGGD and may be a useful biomarker of disease. Sheathed cytology brushes were an effective method for sampling the gastric mucosa.