Effects of parasitism and stress on hemolymph protein of the African giant snail, Achatina fulica.

Effects of parasitism and stress on the protein concentration of hemolymph have been investigated using the rat lungworm Angiostromgylus cantonensis in the snail host Achatina fulica. The normal hemolymph protein concentration, averaging 1.77 g/100 ml in noninfected snails, did not show any reduction when the hosts were infected with third stage larvae. When the infected snails were bled repeatedly, protein concentration showed a significant decrease by 0.6 g/100 ml. Starved, infected snails were capable of maintaining their hemolymph protein level within the normal range. This treatment, however, in combination with frequent bleeding, caused much stress to the snails and reduced survival. The number of survivors depended on the frequency of bleeding and on the food level.