Abstract:
The objective of this study was to evaluate the productive and reproductive performance of cross
bred (HF x zebu) dairy cows at Menkorer agro industry dairy farm enterprise, Debre Markos,
Ethiopia. Six years (2011-2017) of data were collected on crossbred dairy cows. The
independent fixed variables examined were year and season of birth/calving and parity. Data
were analyzed using the General Linear Models (GLM) of (SAS, 2009 Version 9.2). The study
revealed that the overall least square means (±SE) for reproductive traits , age at first service
(AFS), age at first calving (AFC), days open (DO), calving interval (CI), number of services per
conception (NSC) and dry period(DP) were 18.28 ± 1.84 months, 27.67 ±1.86 months,97.3±10.1
7 days, 13.70±0.83 months,1.3 ± 10.02 and 53.75 ± 0.08 days respectively. The overall least squ
are means (±SE) for productive traits, average daily milk yield (ADMY), lactation milk yield (LM
Y), lactation length (LL), and birth weight were 12.26 ±0.06 liters, 4254.7±5126.72 liters, 354.88
±5.70 days, and 42.41±0.01 kg respectively. An increased efficiency in reproductive performance
of cows was observed over time. Season of birth and year had significant (P<0.05) effect on
AFS and AFC. Season of calving had significant (P<0.05) effect on DO, CI, LMY and highly
significant (p<0.01) effect on DP and BW, ADM and LL which were improved during long rainy
seasons than dry and short rainy seasons. This improvement may be due to the abundant green
fodder available during birth of the animals. Year of calving had highly significant (p<0.01)
effect on DO, ADMY and LL and had significant effect (p<0.05) on DP and BW. Parity had also
significant effect (p<0.05) on DO, CI and DP and had significant effect (p<0.01) on ADMY LL,
LMY, DP and BW. DO decrease over parity (1 to 5) whereas ADMY and LMY increased over
time. The study showed that even if productive and reproductive performance of crossbred cows
in the study area was good compared with the performance of crossbreds in different areas of
Ethiopia, still farm needs better management practices, proper breeding management and use of
reproductive technology to improve the efficiency of reproductive performances
