Ocorrência de hematúria enzoótica e neoplasias do trato alimentar superior em búfalos no Brasil

Abstract

Plants of the genus Pteridium spp. they are among the most important toxic plants in the world, given their cosmopolitan distribution and, mainly, for their high carcinogenic potential for animals and humans. In the Southeast Region, Pteridium esculentum subsp. arachnoideum, a plant popularly known as "bracken fern" or "field bracken fern" is one of the plants that cause the greatest economic damage in livestock. The carcinogenic effect is due to the presence of a norsesquiterpene called ptakiloside, a toxic principle of radiomimetic action, whose action may vary depending on the animal species, the time of ingestion and the daily amount ingested. Ingestion of Pteridium spp. it causes different clinical-pathological conditions attributed to the plant's radiomimetic action: Hemorrhagic Diathesis (HD), Enzootic Hematuria (EH) and Upper Digestive Tract Neoplasms (UDT), and these types of poisoning are commonly described mainly in cattle. So far, there are rare references to EH in buffaloes. Regarding UDT and HD neoplasms, there were no reports of occurrence in this species. In the Southeast Region, at least, EH is responsible for the largest number of losses, due not only to death, but also due to the decrease in productivity. In São José do Barreiro/SP, for approximately 13 years, some farmers in areas with a high incidence of this disease have been replacing cattle with buffaloes, based on the premise that they would be more resistant to EH than cattle. Although, according to initial observations, buffaloes are actually less sensitive than cattle, nevertheless the occurrence of cases of hematuria concomitant with neoplasms of UDT in this species has been verified. According to the epidemiological survey, these diseases only occur in buffaloes over six years old. The three animals followed in the present study, however, had good nutritional status and, except for eliminating blood with urine, apparently were healthy. In relation to the bladder, there was a thicken mucosa, ulcerated, multifocal, exophytic, papilliform, verrucous, pedunculated lesions. Histologically neoplastic and non-neoplastic changes similar to those described in cattle with EH were observed. Neoplastic and non-neoplastic lesions were present at the base of the tongue, along with attached tissues of the oropharynx, larynx and esophagus and were characterized by multiple foci of exophytic proliferative lesions, pedunculated in the shape of cauliflower or cone ("cutaneous horn-like"), as well as circular plaque lesions, often ulcerated. Among benign neoplasms, papillomas and a fibroma were found. Regarding malignant ones, carcinomas with squamous differentiation and carcinoma in situ were observed. The occurrence of HE and UDT Neoplasms in Buffaloes in Brazil is described for the first time.