TY - JOUR
T1 - Effects of trematode double infection on the shell size and distribution of snail hosts
AU - Miura, Osamu
AU - Chiba, Satoshi
N1 - Funding Information:
We thank Yoshiki Sasaki, Naoyuki Takahashi, and Shiro Ogihara for their assistance in the sampling of B. attramentaria. We also thank Ryan Hechinger for providing valuable information on trematode species in B. attramentaria. Two anonymous reviewers provided useful comments. This study was supported by grants from the Japan Society for the Promotion of Science.
PY - 2007/3
Y1 - 2007/3
N2 - Infection with larval trematodes sometimes alters the phenotypes of their snail hosts. While some trematode species have distinct effects on host phenotypes, it is still unclear how snail phenotypes are altered when they are parasitized with multiple trematode species. Here, we report that double infection with trematode species averages the effects of parasitic alteration on host phenotype. We found that snail hosts Batillaria attramentaria (Batillariidae) infected with Cercaria batillariae (Heterophyidae) have abnormally large shells and distribute in lower areas of the intertidal zone. Snails with another dominant trematode species, the renicolid cercaria I (Renicolidae), have slightly larger shells and distribute in upper areas of the intertidal zone. A number of double infections with both trematodes was observed in this study. Snails infected with both trematode species exhibited an intermediate size and inhabited a depth between those of snails solely infected with either trematode species, suggesting that the two trematodes simultaneously affected the snail phenotypes. Because altered host phenotypes are frequently beneficial to parasites, two trematode species may compete for successful transmission through alteration of host phenotypes.
AB - Infection with larval trematodes sometimes alters the phenotypes of their snail hosts. While some trematode species have distinct effects on host phenotypes, it is still unclear how snail phenotypes are altered when they are parasitized with multiple trematode species. Here, we report that double infection with trematode species averages the effects of parasitic alteration on host phenotype. We found that snail hosts Batillaria attramentaria (Batillariidae) infected with Cercaria batillariae (Heterophyidae) have abnormally large shells and distribute in lower areas of the intertidal zone. Snails with another dominant trematode species, the renicolid cercaria I (Renicolidae), have slightly larger shells and distribute in upper areas of the intertidal zone. A number of double infections with both trematodes was observed in this study. Snails infected with both trematode species exhibited an intermediate size and inhabited a depth between those of snails solely infected with either trematode species, suggesting that the two trematodes simultaneously affected the snail phenotypes. Because altered host phenotypes are frequently beneficial to parasites, two trematode species may compete for successful transmission through alteration of host phenotypes.
KW - Behavioural modification
KW - Double infection
KW - Gigantism
KW - Trematodes
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U2 - 10.1016/j.parint.2006.10.002
DO - 10.1016/j.parint.2006.10.002
M3 - Article
C2 - 17113818
AN - SCOPUS:33847080308
VL - 56
SP - 19
EP - 22
JO - Parasitology International
JF - Parasitology International
SN - 1383-5769
IS - 1
ER -