Genotypes and morphologies of bovine papillomavirus in Costa Rica

Abstract Bovine papillomaviruses (BPV) infect the basal layer of the epithelium of bovines, where they persist asymptomatically or produce benign fibroepithelial hyperplasia in the skin or mucosa. The present study aimed to describe the genotypes of bovine papillomas at macroscopic and microscopic level. A descriptive study was carried out, using a non-probabilistic convenience sampling. Ninety-nine papillomas from 63 animals out of 32 farms were collected, as well as information about age, gender, breed, and productive use of the bovines. The location, type and degree of epithelial invasion of the papillomas was recorded. The samples were subjected to molecular and histopathological analysis. The highest number of bovines with papillomas was found in dairy farms (75,0%), in females (95.0%), Holstein breed (45,0%), and animals with ages over 24 months (50,0%). Most of the animals presented from 1 to 15 papillomas (31.6%) and only one type of papilloma (79.4%). Cauliflower-like papillomas were found in 48.5% of the cases, while the atypical papilloma in 11.1% cases. Cauliflower-like papillomas were found mainly in udder (14,4%), head (10,0%) and neck (10,0%) and were associated to five BPV genotypes (BPV1, BPV2, BPV6, BPV7 and BPV10) while BPV2 and BPV6 were found associated with all types of papillomas (cauliflower, flat, pedunculated and atypical). The presence of BPV11 in flat and BPV6 in atypical papillomas is reported for the first time. The morphology and histopathological findings did not allow a differentiation of the BPV genotypes.