Departamento de Produção Vegetal, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de Acesso Prof. Paulo Donato Castellane, s/n, CEP 14884-900, Jaboticabal, SP, Brazil.
Vet Parasitol. 2009 Dec 3;166(1-2):136-43. doi: 10.1016/j.vetpar.2009.07.037. Epub 2009 Jul 29.
The efficacy of M. anisopliae strain E9 as a biological insecticide for the adult and larval stages of H. irritans was assessed under field conditions. To assess larvicidal activity, nine heifers were randomly divided into three groups, which were maintained separated from each other. The first group ingested fungal spores encapsulated in alginate pellets. The second group ingested in natura spores that were grown on sterilized rice. In both groups, each animal received three meals a day, with each meal containing 2 x 10(10)conidia. The third group received no treatment and was used as a control. Fecal samples from manure and whole dung pats were collected from each of the three separate pastures on the day that the animals were allocated and on days 1, 3, 6, 9 and 12 afterwards. The fecal samples were tested for the presence of fungal colony forming units (CFU), and the emergence of horn flies was observed in the dung pats. Significantly less (P<0.01) adult horn flies were found in dung pats of the group treated with encapsulated fungi (11.7) than in those from the heifers treated with conidia in natura (27.9) or from the control group (29.5). The fecal samples of the treated animals presented significantly higher numbers of M. anisopliae CFUs then those from the untreated controls. We found that on day 9 fecal samples from animals given microencapsulated conidia had significantly higher CFUs than those from animals treated with conidia in natura. To assess adulticide activity, four heifers were sprayed with a suspension of 3 x 10(10)conidial(-1) of M. anisopliae, and four control animals were sprayed with the same solution without conidial content. Four sprayings were done at five-day intervals, and all animals were photographed daily to observe the quantity of flies present. After the second spraying, we observed an average of 22.9 flies per animal; untreated heifers had an average of 43 flies per animal; thus, the treatment significantly (P<0.05) decreases fly infestation. The results obtained from both tests show that M. anisopliae strain E9 has a pathogenic effect on H. irritans larvae in bovine manure when administered orally and on adult fly infestations when applied as a spray on the hosts.
在田间条件下评估了 M. anisopliae 菌株 E9 作为生物杀虫剂对 H. irritans 成虫和幼虫阶段的功效。为了评估幼虫的致死活性，将 9 头小母牛随机分为 3 组，彼此分开饲养。第一组摄入包埋在藻酸盐丸中的真菌孢子。第二组摄入在灭菌大米上生长的天然孢子。在这两组中，每头动物每天吃三餐，每餐含有 2 x 10(10)个孢子。第三组未接受治疗，用作对照。在将动物分配到各自的三个单独牧场的那天以及之后的第 1、3、6、9 和 12 天，从每个单独的牧场上收集粪便和整个粪便垫中的粪便样本。测试粪便样本中真菌集落形成单位（CFU）的存在，并观察粪便垫中角蝇的出现。用包埋真菌处理的粪便垫中的成虫角蝇明显较少（P<0.01）（11.7）比用天然孢子处理的小母牛（27.9）或对照组（29.5）中的成虫角蝇少。处理动物的粪便样本中 M. anisopliae CFU 的数量明显高于未处理对照动物。我们发现，在第 9 天，给予微囊化孢子的动物的粪便样本中的 CFU 明显高于用天然孢子处理的动物的粪便样本中的 CFU。为了评估成虫活性，将 4 头小母牛用 3 x 10(10)个孢子(-1)的 M. anisopliae 悬浮液喷雾，将 4 头对照动物用相同的不含孢子的溶液喷雾。每五天进行四次喷雾，每天对所有动物进行拍照以观察存在的苍蝇数量。第二次喷雾后，我们观察到每只动物平均有 22.9 只苍蝇；未处理的小母牛每只动物平均有 43 只苍蝇；因此，该处理显著（P<0.05）减少了苍蝇的侵扰。两项测试的结果均表明，当以口服方式施用于牛粪中的 H. irritans 幼虫时，以及当以喷雾形式施用于宿主上时，M. anisopliae 菌株 E9 对角蝇成虫的侵害具有致病性作用。
