Agricultural College, ATVET, Holleta, Ethiopia; Bair Dar University, P.O.Box 1866, Bahir Dar, Ethiopia
Mureda, E., Agricultural College, ATVET, Holleta, Ethiopia; Zeleke, Z.M., Bair Dar University, P.O.Box 1866, Bahir Dar, Ethiopia
A study was conducted to assess reproductive performances of 304 crossbred (Holstein Friesian x Zebu) dairy cows kept in small (SSDP), medium (MSDP) and large scale dairy production (LSDP) systems in Eastern lowland of Ethiopia. The overall mean age at first service (AFS) and at first calving (AFC) across all production systems were 25.6 (n=283) and 36.2 (n=210) months, respectively. The AFS and AFC were significantly longer (P≤0.05) in the MSDP than in the SSDP and LSDP systems. The overall mean intervals from calving to first service (CFSI) and from calving to conception (CCI) were 162.5 (n=149) and 218.5 (n=108) days, respectively. The crossbred cows under SSDP management system had shorter (P≤0.05) CFSI and CCI than those managed under MSDP and LSDP. The CFSI and CCI were the longest (P≤0.05) for the first and beyond 6th parities as compared to 2nd, 3rd and 4th parities. The mean calving interval (CI) across all production systems was 17.8 (n=155) months. Cows managed under SSDP system had significantly shorter (P≤0.05) CI as compared to cows managed under MSDP and LSDP. The overall pregnancy, calving and conception to first service rates were 72.8%, 63.4% and 45.9%, respectively with no significant difference (P≥ 0.05) among production systems. In conclusion, crossbred cows under the SSDP management systems had better reproductive performance followed by cows in LSDP. Developing feed resource, effective reproductive health management and reliable AI service could be management options to mitigate some of the prevailing problems.