1909 Dec. 867 The introduction of such large quantities (200 c.c.) of horse-serum.
1926 II. 772/1 Particular reference may..be made to the recent therapeutic use of horse serum in the treatment of..blackwater fever.
1964 M. Hynes (ed. 8) vii. 74 The illustration is that of a rabbit immunized with horse-serum.