Milk yield and reproductive performances of crossbred dairy cows with different genotypes in Ethiopia: a review paper

Crossbreeding for improving milk yield and reproductive performances had started and implemented been long in Ethiopia in different locations. The present study focused on reviewing and generating compiled information about the status (potential) of milk yield and reproductive performances of crossbred dairy cows, which have been done at different stations and farm conditions in different eras. Review results of milk production and reproductive performances in Ethiopia varied greatly from one genotype to another. The on-station lactation milk yield and lactation length were ranged from 1293 to 2957 kg and 303 to 374 days, respectively, whereas the on-farm review results were within the values of on-station conditions. The on-station reproductive performances had also obtained in the range from 25.5 to 30.3 for age at first service (AFS), 28.5 to 46.9 for age at first calving (AFC), 351 to 546 for calving interval (CI), 76 to 243 for days open (DO) and 1.3 to 2.7 for the number of service per conception (NSC), respectively. The on-farm review results for reproductive performances had also within the range of on-station conditions. Among the genotypes, the 50% F1 and 75% Holstein Friesian first generations were considered suitable for milk production parameters, whereas Jersey crosses, especially 50% F1 are recommended for better reproductive performances. The on-station development of 50% F2, F3, and 75% second generations showed low milk production and reproductive performances and the likelihood of producing synthetic breed in this step did not give us a promising result. Regardless of blood level and genotype difference, the performance of on-farm crossbred cows was almost similar to on-station experimental cows. Crossbred cows were affected by non-genetic factors like year, season, and parity, depending on the breed and study location. In general, crossbred cows have good milk yield and reproductive performances compared to indigenous (local) breeds. However, crossbred animals could not exploit their maximum potentials because animals are subjected to different environmental effects.