Domestic bovines as potential environmental bioindicators: analysis of oral epithelium and application in the micronucleus assay

DANIELA M FERRÉ; ROCIO CARRACEDO; A PEDROSA; M CALIRI; LUDUEÑA, HECTOR R.; GORLA, N.B.M.

Revista Veterinaria

Universidad Nacional del Nordeste (UNNE)

Año: 2024 vol. 35

Domestic cattle (Bos Taurus) could be used as bioindicators of the quality of agroecosystems, with the possibility of alerting through cellular biomarkers about possible adverse effects of drugs administered in them or toxic contaminants in the surrounding environment. The micronucleus buccal cytome (MN-cyt buccal) assay is used in human populations for this purpose. The aim of this study was to perform the structural characterization of the epithelium in the anatomical site proposed for performing the oral MN-cyt test in this species and to describe the types and frequencies of cells with nuclear abnormalities (NA) of the bovine oral lining epithelium. Exfoliative cytology of the buccal labial epithelium of twelve castrated males was performed and 1,000 cells per animal were analyzed. The frequencies of basal and differentiated cells with NAs were established. The most frequently observed cell types and NAs were: karyolytic, condensed chromatin, karyorrhexis, pyknotic, kidney-shaped, notched nuclei, binucleated, micronucleated and buds. Four grades of progression were described in nuclei with karyorrhexis. A keratinized flat stratified epithelium of 866.67±75.44 µm thick (Mean ± SD) was evidenced and the characteristics of the cells of the strata germinativum, granulosum, spinosum and corneum are delineated. In addition to being keratinized, the bovine epithelium is three to five times thicker than that recorded in humans due to more differentiated cells. In the prospective use of buccal MN-cyt in bovines, indicators of cell death should not be considered as a result of genotoxic effects that induce apoptosis, as occurs in humans; the rest of the NAs could be used as biomarkers