COMPARATIVE-STUDIES OF FOOD-HABITS AND DIGESTIVE TRACTS IN 2 APODEMUSSPECIES

Feeding experiments using three pairs of food items, analysis of the s caling of digestive organs and microscopic observation were examined i n two woodland rodent species, Apodemus argenteus and A. speciosus. Co mparing the values of selective indices between acorns and three speci es of insects, it was shown that A. argenteus has more intensive prefe rence to insects than does A. speciosus. Both the mean ratio of the ca ecum length to stomach and intestine length (CL/TL) and the ratio of c aecum length to the small intestine length (CL/SIL) in A. speciosus we re significantly larger than those in A. argenteus. Compared to A. spe ciosus, distributions of goblet cells stained with PAS in A. argenteus were dense and homogeneous at most of positions of the small intestin es. These characteristics in the small intestine suggest that A. argen teus depends on more homogeneous and proteinic foods, and support the results from our feeding experiments. From what described above, it wa s implied that these differences in potential food habits are related to the characteristics of foraging behavior, habitat utilization and t erritoriality in the two Apodemus species.