The importance of blood serum immunoglobulin (IgG) concentration, gamma glutamyl transferase (GGT) activity and glutaraldehyde coagulation test (GCT) duration was compared to assess passive transfer status in healthy goat kids. Twenty-one Saanen goat kids (0-15 days old) were used. Blood samples were collected from kids presuckling (day 0, baseline), and on the 1st, 4th, 7th and 15th days. Serum IgG concentration, GGT activity and GCF duration were measured on these days. It was observed that serum IgG concentration and GGT activity significantly increased on the 1st, 4th and 7th day of the experiment. However serum Ca duration was decreased significantly in kids on the 1st, 4th, 7th and 15th days. It was observed that passive transfer status was sufficient when 10% GCT solution clotted serum within 10 and 15 min in up to 7-day-old and 8-15 days old suckling kids, respectively. Thus, GCT as an indicator of GGT activity is useful, practical, and cheaper than GGT in assessing passive transfer status in goat kids. (C) 2010 Elsevier B.V. All rights reserved.