The role of the light/dark cycle in the daily rhythm of serum proteins in Equus caballus

Abstract

This research was carried out on five clinically healthy Sella Italiana horses to determine the daily rhythm of total proteins and their fractions, to establish if these rhythms are endogenously generated and to assess the role of light as synchroniser of these rhythms. Blood samples were collected from each subject every 3 h over a period of 48 h, starting at 9:00 on day 1 and finishing at 9:00 on day 3, into vacutainer tubes without an anticoagulant via intravenous cannulas inserted into the jugular vein. Total serum proteins, albumin,