Ação do fungo metarhizium anisopliae sobre desenvolvimento do díptero muscina stabulans em laboratório / Action of metarhizium anisopliae fungi over the development of muscina stabulans dipteran in laboratory

Avaliou-se o desenvolvimento de Muscina stabulans (Diptera, Muscidae) após exposição ao fungo Metarhizium anisopliae (isolado CG34), sob condições de laboratório. Suspensões de esporos foram preparadas nas concentrações de 10(5), 10(6), 10(7) e 10(8)conídeos/mL-1. Noventa larvas pós-alimentar por tratamento, distribuídas em cinco tratamentos e três repetições, foram mergulhadas por um segundo nas respectivas suspensões, transferidas para placas de Petri com papel filtro umedecido e mantidas em estufa BOD à temperatura de 25ºC, umidade relativa de 80 por cento e fotoperíodo de 12:12 horas até a emergência dos adultos. Foram avaliados a taxa de mortalidade pupal e o período de desenvolvimento pupal. As larvas apresentaram suscetibilidade à ação de M. anisopliae em diferentes concentrações. A mortalidade pupal assim como o tempo de desenvolvimento das pupas (de 8,8 a 10 dias) aumentaram conforme o aumento da concentração de conídios (de zero a 47 por cento). A aplicação de M. anisopliae nesta fase do ciclo biológico comprometeu o desenvolvimento de M. stabulans e interferiu no controle natural de pragas que se desenvolvem no mesmo ambiente.

The development of Muscina stabulans (Diptera, Muscidae) after exposure to Metarhizium anisopliae (CG34 isolated) fungi under laboratory conditions was evaluated. Suspensions of spores were prepared in concentrations of 10(5), 10(6), 10(7), and 10(8)conidia/mL-1. Ninety postfeeding larvae per treatment, divided into five treatments and three repetitions, were dived for one second in the respective suspensions, and transferred to Petri dishes with humidified filter paper and maintained in BOD at 25 ºC with 80 percent relative humidity and a 12:12h photoperiod, until the emergency of adults. The rate of pupal mortality and the period of pupal development were evaluated. The larvae showed susceptibility to the action of M. anisopliae in different levels of concentration. The pupal mortality increased accordingly to the increase in the conidia concentration (from zero to 47 percent), as well as prolonged the time of development of the pupae (from 8.8 to 10 days). The application of M. anisopliae in this phase of the biological cycle compromised the development of M. stabulans and interfered in the natural control of pests that develop in the same environment.

Intragastric pressure and its relevance to protective cricoid force.

Cricoid pressure is frequently used to protect the anaesthetised and paralysed patient from passive regurgitation. Although intragastric pressure (Pga) drives regurgitation, its relevance in the setting of protective cricoid force has been largely ignored. We sought to define the likely range of Pga encountered in the population at risk. We studied 100 consecutive patients presenting for surgery requiring mechanical ventilation. We measured respiratory swings in Pga during mechanical ventilation in the paralysed state following rapid sequence induction (n = 24) and routine induction of anaesthesia (n = 76). Pga (mmHg) in the whole group recorded at end-inspiration (Pga-In) and end-expiration (Pga-Ex) was [mean (SD)]: Pga-In 6.48 (2.60) mmHg and Pga-Ex 3.23 (2.24) mmHg. We found no correlation between Pga and body mass index (r2 = 0.018). These findings have implications for the level of cricoid force required to protect a patient during the induction of anaesthesia.