Factors that influence the duration of useful reproductive life in cattle herds in the province of Camagüey, Cuba

Abstract

218 cows from five different races or crosses were sampled to characterize female bovine reproductive span. Animals were dis- tributed into seven herds out of three livestock centers in Camagüey province. Interval from reproduction cycle beginning to pregnancy by insemination to reproductive span (period between the beginning and the end of the reproduction cycle) was esti- mated. The analysis was carried out through a general lineal pattern, which showed lower values for total number of deliveries, age at the end of the reproduction cycle, interval from reproduction cycle beginning to pregnancy, and age at first calving. Aver- age reproductive span was too short (6,50 ± 0,26 years) due to cattle herd (P<0,05), race or cross (P<0,001), age at the beginning of the reproduction cycle (P<0,001), total number of deliveries (P<0,001), and age at first calving (P<0,001). Holstein x Zebu crossbreeding improved reproductive span compared to purebred cattle and ¾ Zebu x ¼ Charolaise crossing. According to these results, herd handling must be improved and genotype for each place must be properly selected to make possible a decrease in age at the beginning of the reproduction cycle and at first calving, and therefore an increase in the total number of calvings.