The Effect of Crossbreeding on Performance of Crossbred Dairy Cows and Indigenous Cattle Genetic Resources in the North Western Amhara, Ethiopia

In Ethiopia, crossbred cattle are mainly cross of zebu with Holstein-Friesian. The cattle have been used for milk production for decades. Therefore, the objective of the study was to evaluate the effect of crossbreeding on performance of crossbred dairy cows and indigenous cattle genetic resources. The study was conducted in three districts in 2013 namely, Farta, Gondar zuria and Bahir Dar zuria districts. Informal and formal field surveys were employed. Purposive sampling method was used giving due consideration of phenomic traits for cattle populations. Major ecological zones, the distribution of crossbred cattle populations and their socioeconomic importance were considered. The results revealed that the mean daily milk production for 50% Holstein Friesian and 50% indigenous cattle crosses in the Farta (9.14±4.32), Bahir Dar zuria (6.95±2.32) and Gondar zuria (6.27±2.75) districts differed significantly (P<0.001). The reproductive performances of the crossbreed cattle were also differed from district to district as well as from blood level to blood level. The age at first calving for 50% Holstein Friesian and 50% indigenous cattle crosses were found to be 1. 86±0.43, 2.16±0.40, 2.03±0.36 for Farta, Gondar Zuria and Bahir Dar Zuria Districts, respectively. Indiscriminate mating of indigenous cattle with exotic breeds, the existing production system, poorly designed crossbreeding and absence of herd registration and recoding systems are the major causes threatening diversity of indigenous cattle, with index value of 0.18, 0.12, 0.11 and 0.11, respectively. Crossbreeding results in inconsistent and rapid loss of genetic diversity by dilution of the autochthonous genetic makeup and poor heat detection/insemination, with 54.5, 43.6 and 66.34%, respectively. In this study, it was found that as the blood level increases the milk production decreased. The reproductive performance also had shown reduced performance. This can be due to gene segregation and management effects.