Seasonal changes in serum levels of certain metabolites, uric acid and calcium in the migratory Canada goose (Branta canadensis interior)☆

Abstract 1. 1. Changes in serum levels of total protein, albumin, uric acid, glucose, triglycerides, total cholesterol and calcium in the Canada goose were studied during six periods of its yearly life cycle: (1) Spring pre-migratory phase (March) at Swan Lake Refuge (MO, U.S.A.); (2) Spring post-migratory phase (May) at Fort Churchill (Manitoba, Canada); (3) Breeding (June); (4) Moult (August); (5) Fall pre-migratory phase (September); and (6) Fall post-migratory phase (October) (MO, U.S.A.). 2. 2. Low levels of total protein and albumin, and concurrently high levels of uric acid were observed during the breeding, moult and fall pre-migratory phases. 3. 3. Serum glucose and total cholesterol were highest in the fall post-migratory phase while triglycerides were lowest during breeding and moult. Highest triglyceride level was seen in females during the spring post-migratory phase prior to egg-laying. 4. 4. Serum calcium remained constant in both the sexes, except in females during the spring postmigratory phase prior to egg-laying.