Reactions of dairy calves exposed to transport stress at 60 days of postnatal age. Effects of rearing conditions and development quality on physiological variables and their changes.

Dairy calves reared in groups of constant (Gk, N = 16, m 8, w 8) and changi ng composition (Gw, N = 16, m 8, w 8) and single box reared calves (E, N = 15, m 8, w 7) were exposed to transport stress lasting around 60 minutes at 60 days of age. Long term measurements of heart rate (HF) were combined wi th blood sampling (V. jugularis) before and immediately after transport and at the following day as well. Mean differences of HF, Hb, Hk, lactate and blood urea between groups were found at all sampling points. After transpor t mean values of HF, MetHb, pO(2), O(2)SAT and O2CONT were increased in all carves and such of HHb were decreased. Measures of acid-base balance and l actate changed differently in calves of the three rearing groups concerning direction and degree. Changing of the variables after transport comparing the starting values was different between rearing groups in 16 out of 25 po ssible cases. Changing of variables immediately after transport showed stro ng negative correlations with starting values in case of pH, HCO,, base exc ess, COHb, total protein, albumin, lactate, glucose and Ca in all groups, i n all other cases not in all groups. Strong correlations between sampling p oints of Hb, Hk, MCHC, O2CONT, O(2)CAP, creatinine, blood urea and of the m inerals indicate a high individual specificity of these measures. Results p roof variation components of physiological variables in calves caused by hu sbandry conditions and their effects on reactions of animals in case of tra nsport stress.