Biological and physiological changes of Biomphalaria glabrata infected by Heterorhabditis bacteriophora.

The present study investigated for the first time the influence of exposure time (24 or 48 h) of Biomphalaria glabrata (Gastropoda: Pulmonata) to Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae), strain HP88, on some physiological and reproductive parameters of the host mollusk. Throughout the experiment, intense glycogenolysis was observed in both exposed groups, which was more accentuated in the digestive gland. This change was accompanied by a significant increase in the free glucose content in the exposed snails, indicating that H. bacteriophora infection induces the breakdown of host glycemic homeostasis. In parallel, significant variations in lactate dehydrogenase activity in the hemolymph of B. glabrata exposed to entomopathogenic nematodes were observed, confirming the transition from aerobic to anaerobic metabolism in the hosts. This physiological scenario contributed to the establishment of the parasitic castration process in this interface, compromising the reproductive performance of host snails, suggesting the use of H. bacteriophora HP88 as a potential alternative for control of B. glabrata.