Case report: Giant cell tumor of bone in the mandible of a goat-diagnostics, surgical treatment, and outcome

Neoplastic processes of the mandible and their treatment are rarely reported in large animal species. Specifically, giant cell tumor of bone is an uncommon tumor in animals and has been associated in humans with locally invasive behavior and a high recurrence rate. En-bloc resection is the treatment of choice, but depending on the localization of the tumor, this may result in functional deficits. This report details the diagnostic work-up, treatment, and long-term outcome of a giant cell tumor of bone involving the rostral mandible and mandibular symphysis of a goat. Extensive rostral mandibulectomy involving the entire mandibular symphysis without surgical fixation of the hemimandibles was performed. Histological and electron microscopic findings of the tumor were consistent with a giant cell tumor of bone. Although a mutation of the H3F3A gene is considered the driver of tumor development in human giant cell tumors, using molecular analysis, this gene mutation could not be confirmed in this case. Follow-up examinations revealed spontaneous secondary fusion of both hemimandibles and no signs of tumor recurrence. Nearly 1 year after surgery, the owners reported no signs of tumor regrowth.

Management of Risk Factors Associated with Chronic Oral Lesions in Sheep

Oral disorders constitute a significant cause of weight loss in sheep. In a study of disorders of the oral cavity of 36,033 sheep from 60 meat sheep flocks in Spain, we looked for management risk factors associated with chronic oral lesions. Mandibular and maxillary disorders were assessed as an external manifestation of oral lesions by palpation, searching for tissue swellings, fistulae, or open wounds. The prevalence of flocks containing sheep with jaw disorders was 98.3%, with an average individual prevalence of 5.5%. The majority of lesions were located in in the mid-region of the mandible, and the most relevant risk factor was increasing age. Use of acidic diets based on silage and inclusion of hard foods, such as maize straw or hay, was associated with the occurrence of jaw inflammation. It was concluded that hard diets containing plant material with edges and sharp areas, plus acidic foods including silage, are more likely to cause lesions of the gingiva, enabling entry of pathogens to the oral mucosa that eventually establish locally in bony tissues, usually as mandibular osteomyelitis. It was also observed that mineral supplementation appears to prevent the occurrence of these lesions.