Effect of Year of Calving on the Reproductive Performance of Holstein Friesian Cows in Vom Plateau State Nigeria

The study was carried out to estimate the effect of year of calving on reproductive performance traits of Holstein Friesian cows that calved between 2006 – 2017. Five hundred and thirteen (513) calving records obtained from Integrated Dairy Farm Vom were collated for the study. Data was analyzed using the general linear models of SAS 2001 (version 8.0). Results revealed that the overall mean of Age at First Calving (AFC), Calving Internal (CI) and Days Open (DO) were 30.36±0.23 months, 379.70±13.34 days and 93.67± 9.74 days respectively. All the reproductive traits in the study have significant effect (P<0.05) on year of birth of dam. The first, third, fourth and fifth calving interval has significant effect (P<0.05) on year of birth while the second and sixth calving interval had no significant influence (P>0.05) on year of birth. The observed reproductive performance of Holstein Friesian cattle under Vom condition was generally commendable. This may be attributed to improved management practices (such as high quality feed), maternal gene effect, accurate heat detection, timely insemination and adaptation of Holstein Friesian breed to the climatic condition of the study area (due to lower temperature).