Sampling and Preparation of Mouse and Rat Serum

After immunization, samples of serum are taken to check the production of specific antibodies. Serum is collected from clotted blood or plasma without the fibrinogen and other clotting factors. Serum contains fewer proteins than plasma and is preferred for use in many clinical assays because some of the proteins in plasma or the addition of anticoagulants can interfere with the test results. Methods for obtaining blood samples and preparing serum are described here. Blood collection should not exceed 7%–9% of the animal's total blood volume or 1% of total body weight every 2–4 wk.