Cannibalism as a possible entry route for opportunistic pathogenic bacteria to insect hosts, exemplified by pseudomonas aeruginosa, a pathogen of the giant mealworm Zophobas morio

TY - JOUR

T1 - Cannibalism as a possible entry route for opportunistic pathogenic bacteria to insect hosts, exemplified by pseudomonas aeruginosa, a pathogen of the giant mealworm Zophobas morio

AU - Maciel Vergara, Gabriela

AU - Jensen, Annette Bruun

AU - Eilenberg, Jørgen

PY - 2018

Y1 - 2018

N2 - Opportunistic bacteria are often ubiquitous and do not trigger disease in insects unless the conditions are specifically favorable for bacterial development in a suitable host. In this paper, we isolated and identified a bacterium, Pseudomonas aeruginosa, from the larvae of the giant mealworm Zophobas morio and we studied the possible entry routes by challenging larvae with per os injection and subdermal injection. We also evaluated the effect of exposing groups of larvae to P. aeruginosa inoculated in their feed and the effect of exposing wounded larvae to P. aeruginosa. We concluded that the mortality rate of Z. morio larvae is higher when P. aeruginosa gets in direct contact with the hemolymph via intracoelomic injection compared to a situation where the bacterium is force-fed. Larvae with an open wound exposed to P. aeruginosa presented higher mortality rate compared to larvae with a wound that was not exposed to the bacterium. We documented too, that cannibalism and scavenging was more prevalent among larvae in a group, when P. aeruginosa is present compared to when it is absent. We discuss hereby different aspects related with the pathogen’s entry routes to insects the complexity of pathogen’s transmission in high population densities and different ways to prevent and/or control P. aeruginosa in mass rearing systems.

AB - Opportunistic bacteria are often ubiquitous and do not trigger disease in insects unless the conditions are specifically favorable for bacterial development in a suitable host. In this paper, we isolated and identified a bacterium, Pseudomonas aeruginosa, from the larvae of the giant mealworm Zophobas morio and we studied the possible entry routes by challenging larvae with per os injection and subdermal injection. We also evaluated the effect of exposing groups of larvae to P. aeruginosa inoculated in their feed and the effect of exposing wounded larvae to P. aeruginosa. We concluded that the mortality rate of Z. morio larvae is higher when P. aeruginosa gets in direct contact with the hemolymph via intracoelomic injection compared to a situation where the bacterium is force-fed. Larvae with an open wound exposed to P. aeruginosa presented higher mortality rate compared to larvae with a wound that was not exposed to the bacterium. We documented too, that cannibalism and scavenging was more prevalent among larvae in a group, when P. aeruginosa is present compared to when it is absent. We discuss hereby different aspects related with the pathogen’s entry routes to insects the complexity of pathogen’s transmission in high population densities and different ways to prevent and/or control P. aeruginosa in mass rearing systems.

KW - Bacterial infection

KW - Cannibalism

KW - Disease transmission

KW - Entry route

KW - Insect rearing

KW - Opportunistic microorganism

U2 - 10.3390/insects9030088

DO - 10.3390/insects9030088

M3 - Journal article

C2 - 30042293

AN - SCOPUS:85051072540

SN - 2075-4450

VL - 9

SP - 1

EP - 15

JO - Insects

JF - Insects

IS - 3

M1 - 88

ER -