Epidemiological, clinical and pathological aspects of an outbreak of periodontitis in sheep

Abstract

The objective of this study was to describe the epidemiological, clinical and pathological aspects of an outbreak of periodontitis in sheep that occurred on a rural property in Benevides, in the state of Pará, Brazil. The first clinical signs of this disease in the herdvisible nodular swollen mandible -were observed about one month after the sheep began grazing on a recently renovated Panicum maximum cv. Massai pasture; the animals were also supplemented with elephant grass (Pennisetum purpureum). From the 545 adult Santa Ines, Dorper, Texel and crossbred sheep, 20 (3.7%) showed facial bulging, particularly of the mandible. These 20 sheep, which were generally over 36 months of age, had low body condition scores as well as dull and ruffled coats; many of them had loose or missing pre, upper or lower molars, showed the formation of abscesses and fistulas, exhibited pain upon palpation and had difficulty chewing. In the same herd, the prevalence of periodontal lesions at the premolars and molar teeth was evaluated via post-mortem examination of 39 young and 17 adult sheep. In 51.3% (20/39) of adolescents and in 100% of adults, periodontal lesions were found at least at one tooth of the dental arch, with unilateral or bilateral periodontal lesions at the maxillary and mandibular teeth. Histopathological analysis of 13 sheep revealed pyogranulomatous inflammation. The second and third maxillary premolars were the teeth that were most affected in young animals, whereas the third pre-molar and the molars, of the maxilla and mandible, were most often affected in adults. These lesions led to severe bone destruction, alterations in the dental arch, occlusion, tooth loss and periodontal abscesses. The epidemiological and clinic-pathological characteristics of this periodontitis outbreak, described here for the first time in sheep in Brazil, were similar to those for bovine periodontitis ("cara inchada"). No mesmo rebanho, a prevalência de lesões periodontais nos dentes pré-molares e molares foi avaliada por meio do exame post-mortem em 39 ovinos jovens e 17 adultos. Assim, 51,3% (20/39) dos jovens e todos os adultos apresentavam lesões periodontais em pelo menos um dos dentes da arcada, com ocorrência uni ou bilateral nos maxilares e mandibulares. A análise histopatológica de 13 animais revelou processo inflamatório piogranulomatoso. Os dentes mais afetados nas arcadas dos animais jovens foram os segundo e terceiro pré-molares maxilares. Já nos adultos foram o terceiro pré-molar e os molares, tanto maxilares quanto mandibulares. As lesões causaram severa destruição óssea, alteração na arcada dentária, na oclusão, perda dental e ocorrência de abscessos periodontais. As características epidemiológicas e clínico-patológicas do surto de periodontite em ovinos, aqui descritos originalmente nesta espécie animal no País, assemelham-se às da periodontite bovina ("cara inchada").TERMOS DE INDEXAÇÃO: Doença periodontal, periodontite, epidemiologia, ovinos.

Prevalence of dental and mandibular disorders in culled sheep in Spain

“…This tooth is the one that supports most pressure in the mastication process, and for that reason, it suffers the most wear and tear 13 . However, in the necropsies of the 17 adult sheep carried out in the study of Silva et al, 14 the third premolar, first, second and third upper and lower molars were the teeth most frequently affected. In addition, the difference in losses found between the first premolar and the third molar (34.8% vs 8.2%) was probably due to the size, number of lobes and number of tooth roots.…”

Subgingival bacterial microbiota associated with ovine periodontitis

“…In this context, periodontal disease and excessive tooth wear are the main disturbances affecting the tooth supporting structures and teeth of sheep (West & Spence 2000). In Brazil, ovine periodontitis has been diagnosed in the North (Silva et al 2016) and Southeast (Borsanelli et al 2016, Agostinho 2017 regions. In the studied herds, this disease was responsible for serious economic losses due to animal weight loss and death (Silva et al 2016).…”

“…Periodontal infection in sheep resulted from an acute process, with severe gingival retraction, attachment loss of the premolar and molar teeth, purulent exudate, bulging of the mandible or maxilla, teeth loss, defects in occlusion, difficulty in rumination, emaciation, and eventual death of animals, clinically characterizing a severe condition (Silva et al 2016). Despite the growing evidence of primary infectious etiology in periodontal diseases in human medicine and in some animal species, few studies have highlighted the role of specific subgingival microbiota in periodontal disease in ruminants.…”

“…Samples of purulent exudate of the periodontal pocket of 14 sheep with severe clinical signs of periodontitis were obtained during an outbreak of the disease, reported by Silva et al (2016), in a property located in the municipality of Benevides, state of Pará, Brazil. Samples were collected only from periodontal pockets with depth greater than 5mm using sterile swabs, transferred to cryotubes containing ultrapure water, and stored in liquid nitrogen until processing.…”

“…Therefore, molecular methods can be used in the detection and evaluation of possible associations between specific microorganisms and periodontitis (Ashimoto et al 1996). Silva et al (2016) reported an outbreak of periodontitis in a sheep herd in the state of Pará, Brazil, with high prevalence and severe clinical signs of periodontitis, weight loss, death, and epidemiological conditions similar to those occurring in episodes of bovine periodontitis. Therefore, the objective of the present study was to identify, through PCR, the presence of specific periodontopathogens in samples of periodontal pocket in animals with periodontitis and of subgingival sulcus biofilm in periodontally healthy sheep.…”