Growth and development quality of dairy calves reared in groups with an automatic milk feeder. Physiological variables and their changes at specific age periods

On 38 dairy calves (20 male, 18 female) measurements of growth performance and of body temperature (RT) and blood sampling were made at 15, 30, 60 and 90 days of age of the carves. Blood was analysed for acid-base balance, bi ochemical and hematological values, minerals and hemoglobin derivatives. Ef fects of season (group 1: calvings from October till December; group 2: cal vings from January till April) and of gender were considered. Growth perfor mance was different between the groups at all age points. Group effects exi sted at 15 days (RT, Hk, MetHb, Laktat, P), at 30 days (RT, P), at 60 days (Hb, O(2)CAP, pH, BE, HCO3, P), at 90 days (pCO(2), blood urea, Mg, Fe). Ge nder effects became obvious at 30 days (O2CONT, O(2)SAT, MetHb, HHb, pCO(2) ). Interactions of group and gender occured at 15 days (P), at 30 days (O2C ONT, pCO(2)), at 60 days (COHb, Mg) and at 90 days (Hb, O(2)CAP). Between a ge point mean differences could be found for acid-base status, total protei n, albumin, creatinine, blood urea, glucose, Mg and for the hematological v ariables. In most cases between age point changes of variables showed stron g negativ correlations with the starting values at 15 days of age. Directed changes of most variables within life age periods developed with different degrees depending on development quality and on specific husbandry conditi ons.