none The body weight of the host was considerably reduced on attack by the parasitoid, Apanteles glomeratus Linnaeus. It varied from 466.65 plus or minus 87.78 mg to 177.94 plus or minus 52.01 mg. Average weight of the parasitoids per host was 268.54 plus or minus 80.86 mg and individual parasitoid weighed 3.12 mg. There was a reduction in the total body lipid: from 8.85 plus or minus 1.27% (wet wt) in the normal caterpillar to 1.93 plus or minus 0.42% in one batch and to 5.15 plus or minus 0.80 in another batch of infected caterpillars. The haemolymph protein content of the host also showed a reduction from 9.89 plus or minus 1.29 to 3.59 plus or minus 0.76%. Biometrics; Biochemistry; Chemical composition; Circulatory system; Blood; Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Insect hosts; Host parasite relationships Pieris brassicae (Pieridae); Weight; Lipid and fatty acid content; Blood and serum proteins; Haemolymph; Proteins, hymenopteran parasite effects; Hymenopteran parasites; Apanteles glomeratus; Parasite effects on haemolymph protein, lipid content & weight; Reaction of host to parasite; Biochemical & weight changes in response to hymenopteran parasite Apanteles glomeratus (Braconidae); Lepidopteran hosts; Pieris brassicae; Parasite effects on host haemolymph protein; Reaction of host to parasite; Pieris brassicae (Lepidoptera) haemolymph protein, lipid content & weight