Passive transfer of immunity in Nelore and Limousin calves and serum proteinogram in the first four months of life.

To study the passive transfer of immunity, 90 healthy calves, 45 Nelore and 45 Limousin, were grouped (n=15) according to their dam's parity: first, second or third or more calvings. Blood samples were draw from each calf with 24 to 36 hours of life and 15, 30, 60, 90, and 120 days. The total serum (TSP) and plasma (TPP) proteins, gamaglutamiltransferase activity (GGT), serum albumin, alpha, beta and gammaglobulin by electrophoresis in agarose gel and IgG estimated by the zinc sulphate turbidity test were determined. Two-way-ANOVA was used to compare the data in the first age. The age behaviour was analysed through repeated measures ANOVA. Correlations were established between the variables. The passive transfer of immunity was successful in both breeds and the parity of the dam had no effect on the calves' serum gammaglobulin concentration. The levels of gammaglobulins were higher at the end of the first day of life, and decreased until 60 days. From there on, the increase due to the active production of antibodies was precocious in taurine calves and slower in Zebu calves. At the end of the first day of life, the gammaglobulin was correlated with IgG (r=0,859), TPP (r=0,807), TSP (r=0,811) and GGT (r=0,399). The variation of serum proteins followed the normal pattern throughout the first four months of life, with little differences between taurine and Zebu calves.