White Cuban Zebu reproductive behavior

Abstract

7 896 calvings registered at the Genetic Center Rescate de Sanguily, in Camaguey province,  Cuba,  from  1982   to  2001   in  five  herds of  Cuban White  Zebu   cows ranging between 2,4 and  13,8  years old were  studied to determine the influence of some environmental and  genetic factors such as herd,  cow age  at  calving, calving number, and  calving time (every  two  months and  five years) upon  the  following traits:   service   period,   intercalving   period,   pregnancy  time   and    service   per pregnancy. A statistical  analysis  of  results  was performed  using  a  linear  model from the least squares method (Systat, 1992)  to estimate each trait average values and  their standard errors.  Service period, intercalving period, and  pregnancy time were  influenced (P<0,01) by herd,  calving time and  offspring birth year,  but calving year  and  number remained unchanged. Service per pregnancy was also influenced (P<0,01)  by  all  and  every  environmental  and  genetic  factors.  General  average values and  their standard errors were:  service period 289,7  ± 5,3 days;  intercalving period, 579,3  ± 10,7  days;  pregnancy time, 289,57 ± 5,3  days,   and  service per pregnancy 1,7 ± 0,9 days in relation to inseminations performed determinant coefficients showed low values (2; 2; 2; and 7 % respectively) for each studied trait.