DAILY FLUCTUATIONS OF HEMATOLOGY AND BLOOD BIOCHEMISTRY IN HORSES FEDVARYING LEVELS OF PROTEIN

Changes in the plasma biochemistry of 12 stallions were studied over s even 24 h periods, Twelve healthy male horses of 4 different breeds (T horoughbred [TB], Anglo-Arabo-Sardo [AAS], Avelignese [Av] and Maremma no [M]) were divided into 3 experimental groups and fed with an isoene rgetic maintenance ration with different protein levels, The same amou nt of food was given daily at 0730 and 1930 h, After 20 days of pretri al, a series of 6 blood samples were collected daily from the jugular vein every 4 h for 7 days, The samples were analysed for packed cell v olume (PCV), haemoglobin, plasma glucose, free fatty acids, cholestero l, total plasma protein, urea, creatinine, calcium, phosphorus and enz ymatic activities: aspartate aminotransferase (AST), alanine aminotras ferase (BLT), creatine kinase (CK) and lactate dehydrogenase (LDH), Th e data were analysed following the armonic analysis (Fourier) in order to define the pattern of biorhythm, Many parameters showed a biorhyth mical pattern, Protein levels of the diet failed to influence haematol ogy, blood biochemistry and biorhythm, Thoroughbreds showed the highes t values of PCV, haemoglobin and creatinine and the lowest total prote in, phosphorus and enzymatic activities.