The main objective of this study was to estimate genetic and phenotypi
c trends in weights at birth (BW), 8 (W8) and 12 months (W12) of age;
and also in the daily gains from birth to 8 months (G8) and from birth
to 12 months (G12) for the ''Guzera'' cattle herd from the ''Fazenda
de Ensino e Pesquisa do Campus de Ilha Solteira'', UNESP, at Selviria,
MS, in the Central-West region of Brazil. The data were collected bet
ween 1979 and 1984 from 842 calves, sired by 22 sires. Genetic trends
were estimated by three alternative procedures, two of them were based
on the methodology of repeated use of sires and the other procedure o
n the differences in the average genetic values of sires in the differ
ent years. The phenotypic annual changes estimated were -0.232 kg, -8.
278 kg, -0.033 kg, -8.498 kg e -0.023 kg, for BW, W8, G8, W12 and G12,
respectively. The estimates of genetic trends, obtained by the three
procedures were different, but showed that genetic changes for all ana
lised traits were little.