Productive and reproductive performance of Friesian cows at Kitulo livestock multiplication unit, Tanzania
Retrospective data were collected to assess reproductive and productive performance of Friesian dairy cows reared at Kitulo Livestock Multiplication Unit, Tanzania. Records of 314 cows within consecutive five productive periods; 2009 - 2014 were analyzed using Statistical Package for SocialScience (SPSS). The overall mean age at first calving (AFC), calving interval (CI), days open (DO), number of services per conception (NSPC), lactation length (LL) and total lactation milk yield (TLMY) were 1151.72±9.63 days, 404.57±1.54 days, 121.82±1.24 days,1.83±0.24, 306.54±5.53 days and 5,042.12±23.73 kg, respectively. CI differed significantly (P < 0.05) as it decreased with increasing parity but did not affect the TLMY. Number of services per conception positively correlated with DO and CI but negatively correlated with parity. Total lactation milk yield was significantly (P < 0.05) influenced by parity and lactation length, but TLMY had no significant (P > 0.05) effect on the average number of services per conception. It is concluded that reproductive and productive performance of Friesian dairy cows in the present study were low to moderate so it is required to improve management practices at the farm for better reproductive and productive performance.
Key words: calving interval, number of services per conception, lactation length, Friesian