Silva Naylene C S, Lima Aldilene S, Silva Carolina R, Brito Danilo R B, Cutrim-Junior José A A, Milhomem Marlise N, Costa-Junior Livio M
Universidade Federal do Maranhão, Programa de Pós-Graduação em Ciências da Saúde, Centro de Ciências Biológicas e da Saúde, São Luís, Maranhão, Brazil.
Programa de Pós-Graduação em Biotecnologia, RENORBIO, São Luís, Maranhão, Brazil.
Vet Parasitol. 2018 Apr 30;254:6-9. doi: 10.1016/j.vetpar.2018.02.034. Epub 2018 Feb 24.
Haemonchus contortus is the most prevalent nematode in tropical and subtropical regions and is responsible for significant losses in small ruminant production systems. Control of this parasite is based on the use of synthetic anthelmintics; although effective, prolonged and indiscriminate use can select for populations of resistant nematodes. Hydrolyzed yeast can help prevent populations of nematodes and is low in cost. The present study aimed to evaluate the preventive effect of hydrolyzed yeast on H. contortus through in vitro and in vivo assays. In in vitro experiments, the yeast preparation was tested at different stages of the H. contortus life cycle via tests of egg hatchability, larval development, larval exsheathment and larval migration. Both eggs and L3 larvae were obtained from sheep artificially infected with a monospecific strain of H. contortus. In in vivo experiments, animals were treated with hydrolyzed yeast (53.4 mg/kg/BW), and fecal egg counts (FECs), feces culture and Famacha were performed. The yeast preparation inhibited larval exsheathment in a dose-dependent manner (IC of 0.46 mg/mL), though no activity at the other stages of the H. contortus life cycle was observed. The hydrolyzed yeast preparation was able to reduce FECs in treated animals from D40 to D54 (p < 0.05), showing an average efficiency of 60%. The yeast exhibited preventive properties, and the IC value suggests that H. contortus is highly susceptible. Our results indicate that administration of hydrolyzed yeast, which is already used commercially in ruminant nutrition, is an alternative method for the control of nematodes, mainly H. contortus.
捻转血矛线虫是热带和亚热带地区最常见的线虫，会给小型反刍动物生产系统造成重大损失。对这种寄生虫的控制基于合成驱虫药的使用；尽管有效，但长期和不加区分地使用会导致产生对线虫有抗性的种群。水解酵母有助于预防线虫种群，且成本低廉。本研究旨在通过体外和体内试验评估水解酵母对捻转血矛线虫的预防效果。在体外实验中，通过检测虫卵孵化率、幼虫发育、幼虫脱鞘和幼虫迁移，在捻转血矛线虫生命周期的不同阶段对酵母制剂进行了测试。虫卵和L3幼虫均取自人工感染单一种株捻转血矛线虫的绵羊。在体内实验中，给动物投喂水解酵母（53.4毫克/千克/体重），并进行粪便虫卵计数（FEC）、粪便培养和Famacha检测。酵母制剂以剂量依赖的方式抑制幼虫脱鞘（半数抑制浓度为0.46毫克/毫升），不过在捻转血矛线虫生命周期的其他阶段未观察到活性。水解酵母制剂能够使治疗动物在第40天至第54天的粪便虫卵计数降低（p<0.05），平均效率为60%。酵母具有预防特性，半数抑制浓度值表明捻转血矛线虫高度敏感。我们的结果表明，投喂已在反刍动物营养中商业化使用的水解酵母，是控制线虫尤其是捻转血矛线虫的一种替代方法。
