On the resistance to heating and cooling of Balantidium coli in culture and some observations regarding conjugation

Comparative study of three xenic media culture for cultivation of Balantidium coli strains

The aim of the present study was to evaluate the growth rate of Balantidium coli in three xenic media cultures. Between 2013 and 2015, 10 B. coli isolates obtained from feces of Cynomolgus macaques, and 30 isolates from feces of pigs were studied. An inoculum of 500 trophozoites was transferred to tubes containing LES, TYSGM-9 and Pavlova media. These cultures were evaluated at incubation times of 24, 48, 72 and 96 hours. In most of strains analyzed wasn't showed significant difference in the growth rate comparing TYSGM-9 and Pavlova media (Wilcoxon p>0.016). In Pavlova medium, the trophozoites showed a maximum growth at 72 hours with significant difference when compared with the times of 24 h and 96 h (Wilcoxon <0.008). In LES, viable trophozoites were observed until 24 hours, with a significant difference (Friedman p<0.05, Wilcoxon p<0.016) in the number of parasite cells compared with Pavlova and TYSGM-9 media cultures. Thus, LES medium seemed to be less adequate than the other media for maintenance of B. coli. Despite the satisfactory results in TYSGM-9, Pavlova medium was considered ideal for the maintenance of this protozoan strain, guaranteeing the viability of the parasite with subculture every three days, presenting lower costs.

Isolation and maintenance of Balantidium coli (Malmsteim, 1857) cultured from fecal samples of pigs and non-human primates

Balantidium coli is a protozoa that can determine dysentery in humans, pigs and non-human primates having zoonotic potential. The lack of standardization in isolation and maintenance hinders the development of research on its biology and epidemiology. This study is aimed to standardize the isolation and maintenance of this parasite from animal feces, in culture medium, Pavlova modified. From 2012 to 2014, 1905 fecal samples were collected from captive animals of Rio de Janeiro. Were selected for isolation samples with a minimum of 10 trophozoites and/or 30 cysts of B. coli, totaling 88 pigs, 26 Cynomolgus and 90 rhesus macaques. In the presence of cysts, the sample was homogenized in saline solution, 500 μL was removed and inoculated into culture medium. The material that contained trophozoites the inoculum was made from 240 μL of fecal solution. All inoculate tubes with the subcultures were kept at 36°C, and sterile rice starch was always added to the medium. The parasites isolate from pigs, 34%, and from Cynomolgus 38.4% were maintained in vitro for a period of more than 24 months. These procedures proved to be adequate for isolation and maintenance of B. coli from different animals, they were found to be inexpensive and easy to perform.