De Souza Maia Filho Fernando, Nunes Vieira Juliana, Aires Berne Maria Elisabeth, Stoll Franciele Elisa, Da Silva Nascente Patricia, Pötter Luciana, Brayer Pereira Daniela Isabel
Departamento de Microbiologia e Parasitologia, Instituto de Biologia, Programa de Pós Graduação em Parasitologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, Brazil.
Rev Iberoam Micol. 2013 Oct-Dec;30(4):226-30. doi: 10.1016/j.riam.2012.12.009. Epub 2013 Feb 9.
Visceral toxocariasis is a parasitic zoonosis caused by Toxocara canis. The prevalence of this parasite in dogs, soil contamination and the resistance of eggs increase human exposure to the disease. Moreover, the difficulties of the control measures justify the need for alternative ones.
The objective of this study was to evaluate the in vitro ovicidal activity of fungi isolated from soils from public places in the city of Pelotas, Rio Grande do Sul, Brazil, on Toxocara canis.
Samples of soil from ten localities were inoculated onto Petri dishes with 2% water-agar (WA) that contained antibiotics, and incubated at 25°C/21 days. Isolated fungi were tested in vitro for ovicidal activity, with five replicates. One mL of an embryonated Toxocara canis egg suspension (10(3) eggs) was poured over the fungal cultures after 10 days of growth. At intervals of 7, 14 and 21 days, 100 eggs were removed from each plaque and evaluated by optical microscopy.
Acremonium, Aspergillus, Bipolaris, Fusarium, Gliocladium, Mucor and Trichoderma were isolated from the soil. A significant ovicidal type 3 effect was observed in Trichoderma, Fusarium solani complex and Acremonium. Those isolates from the genus Trichoderma showed their ovicidal effect on the 14th day of fungus-egg interaction. The other fungal genera tested showed a type 2 effect.
These results suggest that the use of Trichoderma and Fusarium solani complex in biological control of T. canis is promising; however, further studies should be performed.
内脏弓首蛔虫病是由犬弓首蛔虫引起的一种寄生性人畜共患病。这种寄生虫在犬类中的流行、土壤污染以及虫卵的抗性增加了人类感染该疾病的风险。此外，控制措施的困难使得需要寻找替代方法。
本研究的目的是评估从巴西南里奥格兰德州佩洛塔斯市公共场所土壤中分离出的真菌对犬弓首蛔虫的体外杀卵活性。
从十个地点采集的土壤样本接种到含有抗生素的2%水琼脂（WA）培养皿中，在25°C下培养21天。对分离出的真菌进行体外杀卵活性测试，共五个重复。真菌生长10天后，将1 mL含胚犬弓首蛔虫卵悬液（10³个卵）倾注在真菌培养物上。每隔7、14和21天，从每个菌斑中取出100个卵，通过光学显微镜进行评估。
从土壤中分离出了枝顶孢属、曲霉属、双极孢属、镰刀菌属、粘帚霉属、毛霉属和木霉属真菌。在木霉属、茄病镰刀菌复合体和枝顶孢属中观察到显著的3型杀卵效果。木霉属的那些分离株在真菌与卵相互作用的第14天显示出杀卵效果。测试的其他真菌属显示出2型效果。
这些结果表明，木霉属和茄病镰刀菌复合体在犬弓首蛔虫的生物防治中具有应用前景；然而，还需要进一步研究。
