Prevalence of dental and mandibular disorders in culled sheep in Spain

Abstract

At the slaughterhouse, 1465 culled sheep heads were studied in order to identify disorders of the mandibular cheek teeth. Of these, 227 (15.5%) had evidence of osteomyelitis. The lesional profile showed that the mandible was affected in a similar proportion on both sides (46.7% on the right side vs 50.7% on the left side), mainly in the middle region (55.3%) and with most of the lesions closed without fistulisation (89.4%). In addition, swelling was palpable, with an increase in thickness in the area of the affected body (2.65 ± 0.065 cm vs 1.74 ± 0.030 cm). In 78.6% of the animals, the regional lymph nodes were enlarged. Concerning the mandibular cheek teeth, more than half of the animals lacked at least one tooth (57.0%), with the first premolar being the most frequently missing tooth (34.8%) and the third molar the least (8.2%). The impaction of food around the teeth was very common with the posterior molars being more frequently affected. In the knowledge of the authors, this is the first study that analyses the prevalence of mandibular molar and premolar disorders in sheep, and these are revealed as an important condition affecting culled sheep.

Management of Risk Factors Associated with Chronic Oral Lesions in Sheep

“…Few studies have been carried out analyzing the prevalence and risk factors that influence the presence of oral lesions, although this disorder is an important cause of economic loss and early culling in ovine production [3]. The individual prevalence obtained in our study (5.5%) was similar to that obtained by other authors in a study carried out on European domestic sheep (5%) [28].…”

“…The location of a lesion that occurs when the bones of the oral cavity are infected has been well defined in this work, and it is in full accordance with the work previously carried out by this team in the mandibular lesions of culled sheep at the abattoir [3]. The lesion appears mainly in the central region of the mandible and in equal proportion on both sides.…”

“…Although there are many causes of chronic weight loss in sheep, lesions of the oral cavity should always be considered when examining animals of low body condition score. Oral lesions can affect an individual or the herd and can be a relevant cause of culling [1][2][3].…”

“…In the post-mortem examination of 39 young animal heads, the presence of macroscopic lesions was determined in 51.30% of them [20]. In another slaughterhouse study, 227 of 1465 culled sheep heads analyzed (15.5%) had evidence of mandibular osteomyelitis that was externally palpable, with an increase in thickness in the area of the affected body [3]. In sheep, periodontal disease can begin at an early age with gingivitis, which becomes chronic and causes pain while chewing.…”

Nutritional Wasting Disorders in Sheep

“…The postmortem examination of an emaciated sheep should be focused on ruling out lesions associated with endogenous causes of disease, e.g., Johne's disease, maedi-visna, endoparasitosis, poor dentition, etc. [3,4,6,14,15], that may have prompted such status. Grossly, a sheep that died from chronic starvation usually presents with depletion and serous atrophy of fat deposits.…”