The effects of food and parasitism on reproductive performance of a wild rodent

Food and parasitism can have complex effects on small mammal reproduction. In this study, we tested the effects of sex, food and parasitism on reproductive performance of the Taiwan field mouse (Apodemus semotus). In a field experiment, we increased food availability for a portion of the mice in the population by providing sorghum seeds to a set of food stations. We reduced parasite intensity of randomly-chosen mice through ivermectin treatment. We determined the number and quality of offspring for the mice using paternity analysis. We quantified seed consumption with stable carbon isotope values of mouse plasma and parasite intensity with faecal egg counts of intestinal nematodes and cestodes (FEC). In a laboratory experiment, we reduced parasite intensity of randomly-chosen mice through ivermectin treatment. We quantified their immune functions by total white blood cell, percent granulocyte count, and percent lymphocyte count through haematological analyses. We measured the FEC and en...