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

Abstract 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.

摘要 本研究旨在评估结肠小袋纤毛虫（Balantidium coli）在三种异种培养基中的生长速率。2013至2015年间，研究人员对从食蟹猕猴（Cynomolgus macaques）粪便中分离得到的10株结肠小袋纤毛虫分离株，以及从猪粪便中分离得到的30株结肠小袋纤毛虫分离株开展了实验研究。将500个滋养体接种至分别装有LES培养基、TYSGM-9培养基及Pavlova培养基的试管中，于培养24、48、72及96小时后对各组培养物进行检测分析。对多数受试菌株而言，TYSGM-9与Pavlova培养基的生长速率无显著差异（Wilcoxon检验，p>0.016）。在Pavlova培养基中，滋养体于72小时达到生长峰值，该结果与24小时及96小时组相比存在显著差异（Wilcoxon检验，p<0.008）。在LES培养基中，直至24小时仍可检测到存活的滋养体，其寄生虫细胞数量与Pavlova、TYSGM-9培养基的培养物相比存在显著差异（Friedman检验p<0.05，Wilcoxon检验p<0.016）。由此可见，相较于其余两种培养基，LES培养基更不适用于结肠小袋纤毛虫的维持培养。尽管TYSGM-9培养基的培养效果亦较为理想，但Pavlova培养基被认为是维持该原生动物菌株的最优选择，其可保障寄生虫的存活率，且每3天传代一次即可，同时具备更低的培养成本。